From: Charlie Paul <cpaul.windri...@gmail.com>

These files add the spi functionality to the
LSI axxia 5500 board.

Signed-off-by: Charlie Paul <cpaul.windri...@gmail.com>
---
 drivers/spi/Kconfig     |    7 +
 drivers/spi/Makefile    |    1 +
 drivers/spi/spi-acp.c   | 2503 +++++++++++++++++++++++++++++++++++++++++++++++
 drivers/spi/spi-pl022.c |  136 ++-
 4 files changed, 2628 insertions(+), 19 deletions(-)
 create mode 100644 drivers/spi/spi-acp.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 9982998..39f5fdf 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -249,6 +249,13 @@ config SPI_LM70_LLP
          which interfaces to an LM70 temperature sensor using
          a parallel port.
 
+config SPI_LSI_ACP
+       tristate "LSI ACP34xx SPI Controller"
+       depends on PPC_OF
+       help
+         This is the driver for the LSI SPI controller, present in
+         ACP34xx devices. The controller is essentially a AMBA pl022.
+
 config SPI_MPC52xx
        tristate "Freescale MPC52xx SPI (non-PSC) controller support"
        depends on PPC_MPC52xx
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 6b9d2ac..10832a8 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_SPI_MASTER)              += spi.o
 obj-$(CONFIG_SPI_SPIDEV)               += spidev.o
 
 # SPI master controller drivers (bus)
+obj-$(CONFIG_SPI_LSI_ACP)              += spi-acp.o
 obj-$(CONFIG_SPI_ALTERA)               += spi-altera.o
 obj-$(CONFIG_SPI_ATMEL)                        += spi-atmel.o
 obj-$(CONFIG_SPI_ATH79)                        += spi-ath79.o
diff --git a/drivers/spi/spi-acp.c b/drivers/spi/spi-acp.c
new file mode 100644
index 0000000..c3619da
--- /dev/null
+++ b/drivers/spi/spi-acp.c
@@ -0,0 +1,2503 @@
+/*
+ * A driver for the ARM PL022 PrimeCell SSP/SPI bus master on a non ARM
+ * platform.
+ *
+ * Copyright (C) 2008-2009 ST-Ericsson AB
+ * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
+ *
+ * Author: Linus Walleij <linus.wall...@stericsson.com>
+ *
+ * Derived from: drivers/spi/spi-pl022.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/ioport.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/spi/spi.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/of_platform.h>
+#include <linux/of.h>
+#include <linux/spi/eeprom.h>
+#include <linux/amba/pl022.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/scatterlist.h>
+#include <linux/pm_runtime.h>
+
+/*
+ * This macro is used to define some register default values.
+ * reg is masked with mask, the OR:ed with an (again masked)
+ * val shifted sb steps to the left.
+ */
+#define SSP_WRITE_BITS(reg, val, mask, sb) \
+       ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
+
+/*
+ * This macro is also used to define some default values.
+ * It will just shift val by sb steps to the left and mask
+ * the result with mask.
+ */
+#define GEN_MASK_BITS(val, mask, sb) \
+       (((val)<<(sb)) & (mask))
+
+#define DRIVE_TX               0
+#define DO_NOT_DRIVE_TX                1
+
+#define DO_NOT_QUEUE_DMA       0
+#define QUEUE_DMA              1
+
+#define RX_TRANSFER            1
+#define TX_TRANSFER            2
+
+/*
+ * Macros to access SSP Registers with their offsets
+ */
+#define SSP_CR0(r)     (r + 0x000)
+#define SSP_CR1(r)     (r + 0x004)
+#define SSP_DR(r)      (r + 0x008)
+#define SSP_SR(r)      (r + 0x00C)
+#define SSP_CPSR(r)    (r + 0x010)
+#define SSP_IMSC(r)    (r + 0x014)
+#define SSP_RIS(r)     (r + 0x018)
+#define SSP_MIS(r)     (r + 0x01C)
+#define SSP_ICR(r)     (r + 0x020)
+#define SSP_DMACR(r)   (r + 0x024)
+#define SSP_CSR(r)     (r + 0x030)
+#define SSP_ITCR(r)    (r + 0x080)
+#define SSP_ITIP(r)    (r + 0x084)
+#define SSP_ITOP(r)    (r + 0x088)
+#define SSP_TDR(r)     (r + 0x08C)
+
+#define SSP_PID0(r)    (r + 0xFE0)
+#define SSP_PID1(r)    (r + 0xFE4)
+#define SSP_PID2(r)    (r + 0xFE8)
+#define SSP_PID3(r)    (r + 0xFEC)
+
+#define SSP_CID0(r)    (r + 0xFF0)
+#define SSP_CID1(r)    (r + 0xFF4)
+#define SSP_CID2(r)    (r + 0xFF8)
+#define SSP_CID3(r)    (r + 0xFFC)
+
+/*
+ * SSP Control Register 0  - SSP_CR0
+ */
+#define SSP_CR0_MASK_DSS       (0x0FUL << 0)
+#define SSP_CR0_MASK_FRF       (0x3UL << 4)
+#define SSP_CR0_MASK_SPO       (0x1UL << 6)
+#define SSP_CR0_MASK_SPH       (0x1UL << 7)
+#define SSP_CR0_MASK_SCR       (0xFFUL << 8)
+
+/*
+ * The ST version of this block moves som bits
+ * in SSP_CR0 and extends it to 32 bits
+ */
+#define SSP_CR0_MASK_DSS_ST    (0x1FUL << 0)
+#define SSP_CR0_MASK_HALFDUP_ST        (0x1UL << 5)
+#define SSP_CR0_MASK_CSS_ST    (0x1FUL << 16)
+#define SSP_CR0_MASK_FRF_ST    (0x3UL << 21)
+
+/*
+ * SSP Control Register 0  - SSP_CR1
+ */
+#define SSP_CR1_MASK_LBM       (0x1UL << 0)
+#define SSP_CR1_MASK_SSE       (0x1UL << 1)
+#define SSP_CR1_MASK_MS                (0x1UL << 2)
+#define SSP_CR1_MASK_SOD       (0x1UL << 3)
+
+/*
+ * The ST version of this block adds some bits
+ * in SSP_CR1
+ */
+#define SSP_CR1_MASK_RENDN_ST  (0x1UL << 4)
+#define SSP_CR1_MASK_TENDN_ST  (0x1UL << 5)
+#define SSP_CR1_MASK_MWAIT_ST  (0x1UL << 6)
+#define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
+#define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
+/* This one is only in the PL023 variant */
+#define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
+
+/*
+ * SSP Status Register - SSP_SR
+ */
+#define SSP_SR_MASK_TFE                (0x1UL << 0) /* Transmit FIFO empty */
+#define SSP_SR_MASK_TNF                (0x1UL << 1) /* Transmit FIFO not full 
*/
+#define SSP_SR_MASK_RNE                (0x1UL << 2) /* Receive FIFO not empty 
*/
+#define SSP_SR_MASK_RFF                (0x1UL << 3) /* Receive FIFO full */
+#define SSP_SR_MASK_BSY                (0x1UL << 4) /* Busy Flag */
+
+/*
+ * SSP Clock Prescale Register  - SSP_CPSR
+ */
+#define SSP_CPSR_MASK_CPSDVSR  (0xFFUL << 0)
+
+/*
+ * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
+ */
+#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
+#define SSP_IMSC_MASK_RTIM  (0x1UL << 1) /* Receive timeout Interrupt mask */
+#define SSP_IMSC_MASK_RXIM  (0x1UL << 2) /* Receive FIFO Interrupt mask */
+#define SSP_IMSC_MASK_TXIM  (0x1UL << 3) /* Transmit FIFO Interrupt mask */
+
+/*
+ * SSP Raw Interrupt Status Register - SSP_RIS
+ */
+/* Receive Overrun Raw Interrupt status */
+#define SSP_RIS_MASK_RORRIS            (0x1UL << 0)
+/* Receive Timeout Raw Interrupt status */
+#define SSP_RIS_MASK_RTRIS             (0x1UL << 1)
+/* Receive FIFO Raw Interrupt status */
+#define SSP_RIS_MASK_RXRIS             (0x1UL << 2)
+/* Transmit FIFO Raw Interrupt status */
+#define SSP_RIS_MASK_TXRIS             (0x1UL << 3)
+
+/*
+ * SSP Masked Interrupt Status Register - SSP_MIS
+ */
+/* Receive Overrun Masked Interrupt status */
+#define SSP_MIS_MASK_RORMIS            (0x1UL << 0)
+/* Receive Timeout Masked Interrupt status */
+#define SSP_MIS_MASK_RTMIS             (0x1UL << 1)
+/* Receive FIFO Masked Interrupt status */
+#define SSP_MIS_MASK_RXMIS             (0x1UL << 2)
+/* Transmit FIFO Masked Interrupt status */
+#define SSP_MIS_MASK_TXMIS             (0x1UL << 3)
+
+/*
+ * SSP Interrupt Clear Register - SSP_ICR
+ */
+/* Receive Overrun Raw Clear Interrupt bit */
+#define SSP_ICR_MASK_RORIC             (0x1UL << 0)
+/* Receive Timeout Clear Interrupt bit */
+#define SSP_ICR_MASK_RTIC              (0x1UL << 1)
+
+/*
+ * SSP DMA Control Register - SSP_DMACR
+ */
+/* Receive DMA Enable bit */
+#define SSP_DMACR_MASK_RXDMAE          (0x1UL << 0)
+/* Transmit DMA Enable bit */
+#define SSP_DMACR_MASK_TXDMAE          (0x1UL << 1)
+
+/*
+ * SSP Integration Test control Register - SSP_ITCR
+ */
+#define SSP_ITCR_MASK_ITEN             (0x1UL << 0)
+#define SSP_ITCR_MASK_TESTFIFO         (0x1UL << 1)
+
+/*
+ * SSP Integration Test Input Register - SSP_ITIP
+ */
+#define ITIP_MASK_SSPRXD                (0x1UL << 0)
+#define ITIP_MASK_SSPFSSIN              (0x1UL << 1)
+#define ITIP_MASK_SSPCLKIN              (0x1UL << 2)
+#define ITIP_MASK_RXDMAC                (0x1UL << 3)
+#define ITIP_MASK_TXDMAC                (0x1UL << 4)
+#define ITIP_MASK_SSPTXDIN              (0x1UL << 5)
+
+/*
+ * SSP Integration Test output Register - SSP_ITOP
+ */
+#define ITOP_MASK_SSPTXD                (0x1UL << 0)
+#define ITOP_MASK_SSPFSSOUT             (0x1UL << 1)
+#define ITOP_MASK_SSPCLKOUT             (0x1UL << 2)
+#define ITOP_MASK_SSPOEn                (0x1UL << 3)
+#define ITOP_MASK_SSPCTLOEn             (0x1UL << 4)
+#define ITOP_MASK_RORINTR               (0x1UL << 5)
+#define ITOP_MASK_RTINTR                (0x1UL << 6)
+#define ITOP_MASK_RXINTR                (0x1UL << 7)
+#define ITOP_MASK_TXINTR                (0x1UL << 8)
+#define ITOP_MASK_INTR                  (0x1UL << 9)
+#define ITOP_MASK_RXDMABREQ             (0x1UL << 10)
+#define ITOP_MASK_RXDMASREQ             (0x1UL << 11)
+#define ITOP_MASK_TXDMABREQ             (0x1UL << 12)
+#define ITOP_MASK_TXDMASREQ             (0x1UL << 13)
+
+/*
+ * SSP Test Data Register - SSP_TDR
+ */
+#define TDR_MASK_TESTDATA              (0xFFFFFFFF)
+
+/*
+ * Message State
+ * we use the spi_message.state (void *) pointer to
+ * hold a single state value, that's why all this
+ * (void *) casting is done here.
+ */
+#define STATE_START                    ((void *) 0)
+#define STATE_RUNNING                  ((void *) 1)
+#define STATE_DONE                     ((void *) 2)
+#define STATE_ERROR                    ((void *) -1)
+
+/*
+ * SSP State - Whether Enabled or Disabled
+ */
+#define SSP_DISABLED                   (0)
+#define SSP_ENABLED                    (1)
+
+/*
+ * SSP DMA State - Whether DMA Enabled or Disabled
+ */
+#define SSP_DMA_DISABLED               (0)
+#define SSP_DMA_ENABLED                        (1)
+
+/*
+ * SSP Clock Defaults
+ */
+#define SSP_DEFAULT_CLKRATE 0x2
+#define SSP_DEFAULT_PRESCALE 0x40
+
+/*
+ * SSP Clock Parameter ranges
+ */
+#define CPSDVR_MIN 0x02
+#define CPSDVR_MAX 0xFE
+#define SCR_MIN 0x00
+#define SCR_MAX 0xFF
+
+/*
+ * SSP Interrupt related Macros
+ */
+#define DEFAULT_SSP_REG_IMSC  0x0UL
+#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
+#define ENABLE_ALL_INTERRUPTS (~DEFAULT_SSP_REG_IMSC)
+
+#define CLEAR_ALL_INTERRUPTS  0x3
+
+#define SPI_POLLING_TIMEOUT 1000
+
+/*
+ * The type of reading going on on this chip
+ */
+enum ssp_reading {
+       READING_NULL,
+       READING_U8,
+       READING_U16,
+       READING_U32
+};
+
+/**
+ * The type of writing going on on this chip
+ */
+enum ssp_writing {
+       WRITING_NULL,
+       WRITING_U8,
+       WRITING_U16,
+       WRITING_U32
+};
+
+/**
+ * struct vendor_data - vendor-specific config parameters
+ * for PL022 derivates
+ * @fifodepth: depth of FIFOs (both)
+ * @max_bpw: maximum number of bits per word
+ * @unidir: supports unidirection transfers
+ * @extended_cr: 32 bit wide control register 0 with extra
+ * features and extra features in CR1 as found in the ST variants
+ * @pl023: supports a subset of the ST extensions called "PL023"
+ */
+struct vendor_data {
+       int fifodepth;
+       int max_bpw;
+       bool unidir;
+       bool extended_cr;
+       bool pl023;
+       bool loopback;
+};
+
+/**
+ * struct pl022 - This is the private SSP driver data structure
+ * @adev: AMBA device model hookup
+ * @vendor: vendor data for the IP block
+ * @phybase: the physical memory where the SSP device resides
+ * @virtbase: the virtual memory where the SSP is mapped
+ * @clk: outgoing clock "SPICLK" for the SPI bus
+ * @master: SPI framework hookup
+ * @master_info: controller-specific data from machine setup
+ * @kworker: thread struct for message pump
+ * @kworker_task: pointer to task for message pump kworker thread
+ * @pump_messages: work struct for scheduling work to the message pump
+ * @queue_lock: spinlock to syncronise access to message queue
+ * @queue: message queue
+ * @busy: message pump is busy
+ * @running: message pump is running
+ * @pump_transfers: Tasklet used in Interrupt Transfer mode
+ * @cur_msg: Pointer to current spi_message being processed
+ * @cur_transfer: Pointer to current spi_transfer
+ * @cur_chip: pointer to current clients chip(assigned from controller_state)
+ * @next_msg_cs_active: the next message in the queue has been examined
+ *  and it was found that it uses the same chip select as the previous
+ *  message, so we left it active after the previous transfer, and it's
+ *  active already.
+ * @tx: current position in TX buffer to be read
+ * @tx_end: end position in TX buffer to be read
+ * @rx: current position in RX buffer to be written
+ * @rx_end: end position in RX buffer to be written
+ * @read: the type of read currently going on
+ * @write: the type of write currently going on
+ * @exp_fifo_level: expected FIFO level
+ * @dma_rx_channel: optional channel for RX DMA
+ * @dma_tx_channel: optional channel for TX DMA
+ * @sgt_rx: scattertable for the RX transfer
+ * @sgt_tx: scattertable for the TX transfer
+ * @dummypage: a dummy page used for driving data on the bus with DMA
+ */
+struct pl022 {
+       struct platform_device          *dev;
+       const struct vendor_data        *vendor;
+       resource_size_t                 phybase;
+       void __iomem                    *virtbase;
+       struct clk                      *clk;
+       struct spi_master               *master;
+       struct pl022_ssp_controller     *master_info;
+       /* Message per-transfer pump */
+       struct tasklet_struct           pump_transfers;
+       struct spi_message              *cur_msg;
+       struct spi_transfer             *cur_transfer;
+       struct chip_data                *cur_chip;
+       bool                            next_msg_cs_active;
+       void                            *tx;
+       void                            *tx_end;
+       void                            *rx;
+       void                            *rx_end;
+       enum ssp_reading                read;
+       enum ssp_writing                write;
+       u32                             exp_fifo_level;
+       enum ssp_rx_level_trig          rx_lev_trig;
+       enum ssp_tx_level_trig          tx_lev_trig;
+       /* DMA settings */
+#ifdef CONFIG_DMA_ENGINE
+       struct dma_chan                 *dma_rx_channel;
+       struct dma_chan                 *dma_tx_channel;
+       struct sg_table                 sgt_rx;
+       struct sg_table                 sgt_tx;
+       char                            *dummypage;
+       bool                            dma_running;
+#endif
+};
+
+/**
+ * struct chip_data - To maintain runtime state of SSP for each client chip
+ * @cr0: Value of control register CR0 of SSP - on later ST variants this
+ *       register is 32 bits wide rather than just 16
+ * @cr1: Value of control register CR1 of SSP
+ * @dmacr: Value of DMA control Register of SSP
+ * @cpsr: Value of Clock prescale register
+ * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
+ * @enable_dma: Whether to enable DMA or not
+ * @read: function ptr to be used to read when doing xfer for this chip
+ * @write: function ptr to be used to write when doing xfer for this chip
+ * @cs_control: chip select callback provided by chip
+ * @xfer_type: polling/interrupt/DMA
+ *
+ * Runtime state of the SSP controller, maintained per chip,
+ * This would be set according to the current message that would be served
+ */
+struct chip_data {
+       u32 cr0;
+       u16 cr1;
+       u16 dmacr;
+       u16 cpsr;
+       u8 n_bytes;
+       bool enable_dma;
+       enum ssp_reading read;
+       enum ssp_writing write;
+       void (*cs_control)(u32 command);
+       int xfer_type;
+};
+
+/**
+ * null_cs_control - Dummy chip select function
+ * @command: select/delect the chip
+ *
+ * If no chip select function is provided by client this is used as dummy
+ * chip select
+ */
+static void null_cs_control(u32 command)
+{
+       pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
+}
+
+/**
+ * giveback - current spi_message is over, schedule next message and call
+ * callback of this message. Assumes that caller already
+ * set message->status; dma and pio irqs are blocked
+ * @pl022: SSP driver private data structure
+ */
+static void giveback(struct pl022 *pl022)
+{
+       struct spi_transfer *last_transfer;
+
+       pl022->next_msg_cs_active = false;
+
+       last_transfer = list_entry(pl022->cur_msg->transfers.prev,
+                                       struct spi_transfer,
+                                       transfer_list);
+
+       /* Delay if requested before any change in chip select */
+       if (last_transfer->delay_usecs)
+               /*
+                * FIXME: This runs in interrupt context.
+                * Is this really smart?
+                */
+               udelay(last_transfer->delay_usecs);
+
+       if (!last_transfer->cs_change) {
+               struct spi_message *next_msg;
+
+               /*
+                * cs_change was not set. We can keep the chip select
+                * enabled if there is message in the queue and it is
+                * for the same spi device.
+                *
+                * We cannot postpone this until pump_messages, because
+                * after calling msg->complete (below) the driver that
+                * sent the current message could be unloaded, which
+                * could invalidate the cs_control() callback...
+                */
+               /* get a pointer to the next message, if any */
+               next_msg = spi_get_next_queued_message(pl022->master);
+
+               /*
+                * see if the next and current messages point
+                * to the same spi device.
+                */
+               if (next_msg && next_msg->spi != pl022->cur_msg->spi)
+                       next_msg = NULL;
+               if (!next_msg || pl022->cur_msg->state == STATE_ERROR)
+                       pl022->cur_chip->cs_control(SSP_CHIP_DESELECT);
+               else
+                       pl022->next_msg_cs_active = true;
+
+       }
+
+       pl022->cur_msg = NULL;
+       pl022->cur_transfer = NULL;
+       pl022->cur_chip = NULL;
+       spi_finalize_current_message(pl022->master);
+
+       /* disable the SPI/SSP operation */
+       writew((readw(SSP_CR1(pl022->virtbase)) &
+               (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
+
+}
+
+/**
+ * flush - flush the FIFO to reach a clean state
+ * @pl022: SSP driver private data structure
+ */
+static int flush(struct pl022 *pl022)
+{
+       unsigned long limit = loops_per_jiffy << 1;
+
+       dev_dbg(&pl022->dev->dev, "flush\n");
+       do {
+               while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
+                       readw(SSP_DR(pl022->virtbase));
+       } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
+
+       pl022->exp_fifo_level = 0;
+
+       return limit;
+}
+
+/**
+ * restore_state - Load configuration of current chip
+ * @pl022: SSP driver private data structure
+ */
+static void restore_state(struct pl022 *pl022)
+{
+       struct chip_data *chip = pl022->cur_chip;
+
+       if (pl022->vendor->extended_cr)
+               writel(chip->cr0, SSP_CR0(pl022->virtbase));
+       else
+               writew(chip->cr0, SSP_CR0(pl022->virtbase));
+       writew(chip->cr1, SSP_CR1(pl022->virtbase));
+       writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
+       writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
+       writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
+       writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+}
+
+/*
+ * Default SSP Register Values
+ */
+#define DEFAULT_SSP_REG_CR0 ( \
+       GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0)    | \
+       GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
+       GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
+       GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
+       GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
+)
+
+/* ST versions have slightly different bit layout */
+#define DEFAULT_SSP_REG_CR0_ST ( \
+       GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
+       GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, 
SSP_CR0_MASK_HALFDUP_ST, 5) | \
+       GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
+       GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
+       GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
+       GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16)      | \
+       GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
+)
+
+/* The PL023 version is slightly different again */
+#define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
+       GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
+       GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
+       GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
+       GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
+)
+
+#define DEFAULT_SSP_REG_CR1 ( \
+       GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
+       GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
+       GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
+       GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
+)
+
+/* ST versions extend this register to use all 16 bits */
+#define DEFAULT_SSP_REG_CR1_ST ( \
+       DEFAULT_SSP_REG_CR1 | \
+       GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
+       GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
+       GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
+       GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
+       GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10)\
+)
+
+/*
+ * The PL023 variant has further differences: no loopback mode, no microwire
+ * support, and a new clock feedback delay setting.
+ */
+#define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
+       GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
+       GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
+       GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
+       GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
+       GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
+       GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
+       GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) 
| \
+       GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 
13) \
+)
+
+#define DEFAULT_SSP_REG_CPSR ( \
+       GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
+)
+
+#define DEFAULT_SSP_REG_DMACR (\
+       GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
+       GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
+)
+
+/**
+ * load_ssp_default_config - Load default configuration for SSP
+ * @pl022: SSP driver private data structure
+ */
+static void load_ssp_default_config(struct pl022 *pl022)
+{
+       if (pl022->vendor->pl023) {
+               writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
+               writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
+       } else if (pl022->vendor->extended_cr) {
+               writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
+               writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
+       } else {
+               writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
+               writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
+       }
+       writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
+       writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
+       writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
+       writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+}
+
+/**
+ * This will write to TX and read from RX according to the parameters
+ * set in pl022.
+ */
+static void readwriter(struct pl022 *pl022)
+{
+
+       /*
+        * The FIFO depth is different between primecell variants.
+        * I believe filling in too much in the FIFO might cause
+        * errons in 8bit wide transfers on ARM variants (just 8 words
+        * FIFO, means only 8x8 = 64 bits in FIFO) at least.
+        *
+        * To prevent this issue, the TX FIFO is only filled to the
+        * unused RX FIFO fill length, regardless of what the TX
+        * FIFO status flag indicates.
+        */
+       dev_dbg(&pl022->dev->dev,
+               "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
+               __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
+
+       /* Read as much as you can */
+       while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
+              && (pl022->rx < pl022->rx_end)) {
+               switch (pl022->read) {
+               case READING_NULL:
+                       readw(SSP_DR(pl022->virtbase));
+                       break;
+               case READING_U8:
+                       *(u8 *) (pl022->rx) =
+                               readw(SSP_DR(pl022->virtbase)) & 0xFFU;
+                       break;
+               case READING_U16:
+                       *(u16 *) (pl022->rx) =
+                               (u16) readw(SSP_DR(pl022->virtbase));
+                       break;
+               case READING_U32:
+                       *(u32 *) (pl022->rx) =
+                               readl(SSP_DR(pl022->virtbase));
+                       break;
+               }
+               pl022->rx += (pl022->cur_chip->n_bytes);
+               pl022->exp_fifo_level--;
+       }
+       /*
+        * Write as much as possible up to the RX FIFO size
+        */
+       while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
+              && (pl022->tx < pl022->tx_end)) {
+               switch (pl022->write) {
+               case WRITING_NULL:
+                       writew(0x0, SSP_DR(pl022->virtbase));
+                       break;
+               case WRITING_U8:
+                       writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
+                       break;
+               case WRITING_U16:
+                       writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
+                       break;
+               case WRITING_U32:
+                       writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
+                       break;
+               }
+               pl022->tx += (pl022->cur_chip->n_bytes);
+               pl022->exp_fifo_level++;
+               /*
+                * This inner reader takes care of things appearing in the RX
+                * FIFO as we're transmitting. This will happen a lot since the
+                * clock starts running when you put things into the TX FIFO,
+                * and then things are continuously clocked into the RX FIFO.
+                */
+               while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
+                      && (pl022->rx < pl022->rx_end)) {
+                       switch (pl022->read) {
+                       case READING_NULL:
+                               readw(SSP_DR(pl022->virtbase));
+                               break;
+                       case READING_U8:
+                               *(u8 *) (pl022->rx) =
+                                       readw(SSP_DR(pl022->virtbase)) & 0xFFU;
+                               break;
+                       case READING_U16:
+                               *(u16 *) (pl022->rx) =
+                                       (u16) readw(SSP_DR(pl022->virtbase));
+                               break;
+                       case READING_U32:
+                               *(u32 *) (pl022->rx) =
+                                       readl(SSP_DR(pl022->virtbase));
+                               break;
+                       }
+                       pl022->rx += (pl022->cur_chip->n_bytes);
+                       pl022->exp_fifo_level--;
+               }
+       }
+       /*
+        * When we exit here the TX FIFO should be full and the RX FIFO
+        * should be empty
+        */
+}
+
+/**
+ * next_transfer - Move to the Next transfer in the current spi message
+ * @pl022: SSP driver private data structure
+ *
+ * This function moves though the linked list of spi transfers in the
+ * current spi message and returns with the state of current spi
+ * message i.e whether its last transfer is done(STATE_DONE) or
+ * Next transfer is ready(STATE_RUNNING)
+ */
+static void *next_transfer(struct pl022 *pl022)
+{
+       struct spi_message *msg = pl022->cur_msg;
+       struct spi_transfer *trans = pl022->cur_transfer;
+
+       /* Move to next transfer */
+       if (trans->transfer_list.next != &msg->transfers) {
+               pl022->cur_transfer =
+                   list_entry(trans->transfer_list.next,
+                              struct spi_transfer, transfer_list);
+               return STATE_RUNNING;
+       }
+       return STATE_DONE;
+}
+
+/*
+ * This DMA functionality is only compiled in if we have
+ * access to the generic DMA devices/DMA engine.
+ */
+#ifdef CONFIG_DMA_ENGINE
+static void unmap_free_dma_scatter(struct pl022 *pl022)
+{
+       /* Unmap and free the SG tables */
+       dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
+                    pl022->sgt_tx.nents, DMA_TO_DEVICE);
+       dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
+                    pl022->sgt_rx.nents, DMA_FROM_DEVICE);
+       sg_free_table(&pl022->sgt_rx);
+       sg_free_table(&pl022->sgt_tx);
+}
+
+static void dma_callback(void *data)
+{
+       struct pl022 *pl022 = data;
+       struct spi_message *msg = pl022->cur_msg;
+
+       BUG_ON(!pl022->sgt_rx.sgl);
+
+#ifdef VERBOSE_DEBUG
+       /*
+        * Optionally dump out buffers to inspect contents, this is
+        * good if you want to convince yourself that the loopback
+        * read/write contents are the same, when adopting to a new
+        * DMA engine.
+        */
+       {
+               struct scatterlist *sg;
+               unsigned int i;
+
+               dma_sync_sg_for_cpu(&pl022->dev->dev,
+                                   pl022->sgt_rx.sgl,
+                                   pl022->sgt_rx.nents,
+                                   DMA_FROM_DEVICE);
+
+               for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
+                       dev_dbg(&pl022->dev->dev, "SPI RX SG ENTRY: %d", i);
+                       print_hex_dump(KERN_ERR, "SPI RX: ",
+                                      DUMP_PREFIX_OFFSET,
+                                      16,
+                                      1,
+                                      sg_virt(sg),
+                                      sg_dma_len(sg),
+                                      1);
+               }
+               for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
+                       dev_dbg(&pl022->dev->dev, "SPI TX SG ENTRY: %d", i);
+                       print_hex_dump(KERN_ERR, "SPI TX: ",
+                                      DUMP_PREFIX_OFFSET,
+                                      16,
+                                      1,
+                                      sg_virt(sg),
+                                      sg_dma_len(sg),
+                                      1);
+               }
+       }
+#endif
+
+       unmap_free_dma_scatter(pl022);
+
+       /* Update total bytes transferred */
+       msg->actual_length += pl022->cur_transfer->len;
+       if (pl022->cur_transfer->cs_change)
+               pl022->cur_chip->
+                       cs_control(SSP_CHIP_DESELECT);
+
+       /* Move to next transfer */
+       msg->state = next_transfer(pl022);
+       tasklet_schedule(&pl022->pump_transfers);
+}
+
+static void setup_dma_scatter(struct pl022 *pl022,
+                             void *buffer,
+                             unsigned int length,
+                             struct sg_table *sgtab)
+{
+       struct scatterlist *sg;
+       int bytesleft = length;
+       void *bufp = buffer;
+       int mapbytes;
+       int i;
+
+       if (buffer) {
+               for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
+                       /*
+                        * If there are less bytes left than what fits
+                        * in the current page (plus page alignment offset)
+                        * we just feed in this, else we stuff in as much
+                        * as we can.
+                        */
+                       if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
+                               mapbytes = bytesleft;
+                       else
+                               mapbytes = PAGE_SIZE - offset_in_page(bufp);
+                       sg_set_page(sg, virt_to_page(bufp),
+                                   mapbytes, offset_in_page(bufp));
+                       bufp += mapbytes;
+                       bytesleft -= mapbytes;
+                       dev_dbg(&pl022->dev->dev,
+                               "set RX/TX target page @ %p, %d bytes, %d 
left\n",
+                               bufp, mapbytes, bytesleft);
+               }
+       } else {
+               /* Map the dummy buffer on every page */
+               for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
+                       if (bytesleft < PAGE_SIZE)
+                               mapbytes = bytesleft;
+                       else
+                               mapbytes = PAGE_SIZE;
+                       sg_set_page(sg, virt_to_page(pl022->dummypage),
+                                   mapbytes, 0);
+                       bytesleft -= mapbytes;
+                       dev_dbg(&pl022->dev->dev,
+                               "set RX/TX to dummy page %d bytes, %d left\n",
+                               mapbytes, bytesleft);
+
+               }
+       }
+       BUG_ON(bytesleft);
+}
+
+/**
+ * configure_dma - configures the channels for the next transfer
+ * @pl022: SSP driver's private data structure
+ */
+static int configure_dma(struct pl022 *pl022)
+{
+       struct dma_slave_config rx_conf = {
+               .src_addr = SSP_DR(pl022->phybase),
+               .direction = DMA_DEV_TO_MEM,
+               .device_fc = false,
+       };
+       struct dma_slave_config tx_conf = {
+               .dst_addr = SSP_DR(pl022->phybase),
+               .direction = DMA_MEM_TO_DEV,
+               .device_fc = false,
+       };
+       unsigned int pages;
+       int ret;
+       int rx_sglen, tx_sglen;
+       struct dma_chan *rxchan = pl022->dma_rx_channel;
+       struct dma_chan *txchan = pl022->dma_tx_channel;
+       struct dma_async_tx_descriptor *rxdesc;
+       struct dma_async_tx_descriptor *txdesc;
+
+       /* Check that the channels are available */
+       if (!rxchan || !txchan)
+               return -ENODEV;
+
+       /*
+        * If supplied, the DMA burstsize should equal the FIFO trigger level.
+        * Notice that the DMA engine uses one-to-one mapping. Since we can
+        * not trigger on 2 elements this needs explicit mapping rather than
+        * calculation.
+        */
+       switch (pl022->rx_lev_trig) {
+       case SSP_RX_1_OR_MORE_ELEM:
+               rx_conf.src_maxburst = 1;
+               break;
+       case SSP_RX_4_OR_MORE_ELEM:
+               rx_conf.src_maxburst = 4;
+               break;
+       case SSP_RX_8_OR_MORE_ELEM:
+               rx_conf.src_maxburst = 8;
+               break;
+       case SSP_RX_16_OR_MORE_ELEM:
+               rx_conf.src_maxburst = 16;
+               break;
+       case SSP_RX_32_OR_MORE_ELEM:
+               rx_conf.src_maxburst = 32;
+               break;
+       default:
+               rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
+               break;
+       }
+
+       switch (pl022->tx_lev_trig) {
+       case SSP_TX_1_OR_MORE_EMPTY_LOC:
+               tx_conf.dst_maxburst = 1;
+               break;
+       case SSP_TX_4_OR_MORE_EMPTY_LOC:
+               tx_conf.dst_maxburst = 4;
+               break;
+       case SSP_TX_8_OR_MORE_EMPTY_LOC:
+               tx_conf.dst_maxburst = 8;
+               break;
+       case SSP_TX_16_OR_MORE_EMPTY_LOC:
+               tx_conf.dst_maxburst = 16;
+               break;
+       case SSP_TX_32_OR_MORE_EMPTY_LOC:
+               tx_conf.dst_maxburst = 32;
+               break;
+       default:
+               tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
+               break;
+       }
+
+       switch (pl022->read) {
+       case READING_NULL:
+               /* Use the same as for writing */
+               rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
+               break;
+       case READING_U8:
+               rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+               break;
+       case READING_U16:
+               rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+               break;
+       case READING_U32:
+               rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+               break;
+       }
+
+       switch (pl022->write) {
+       case WRITING_NULL:
+               /* Use the same as for reading */
+               tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
+               break;
+       case WRITING_U8:
+               tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+               break;
+       case WRITING_U16:
+               tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+               break;
+       case WRITING_U32:
+               tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+               break;
+       }
+
+       /* SPI pecularity: we need to read and write the same width */
+       if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
+               rx_conf.src_addr_width = tx_conf.dst_addr_width;
+       if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
+               tx_conf.dst_addr_width = rx_conf.src_addr_width;
+       BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
+
+       dmaengine_slave_config(rxchan, &rx_conf);
+       dmaengine_slave_config(txchan, &tx_conf);
+
+       /* Create sglists for the transfers */
+       pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
+       dev_dbg(&pl022->dev->dev, "using %d pages for transfer\n", pages);
+
+       ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
+       if (ret)
+               goto err_alloc_rx_sg;
+
+       ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
+       if (ret)
+               goto err_alloc_tx_sg;
+
+       /* Fill in the scatterlists for the RX+TX buffers */
+       setup_dma_scatter(pl022, pl022->rx,
+                         pl022->cur_transfer->len, &pl022->sgt_rx);
+       setup_dma_scatter(pl022, pl022->tx,
+                         pl022->cur_transfer->len, &pl022->sgt_tx);
+
+       /* Map DMA buffers */
+       rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
+                          pl022->sgt_rx.nents, DMA_FROM_DEVICE);
+       if (!rx_sglen)
+               goto err_rx_sgmap;
+
+       tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
+                          pl022->sgt_tx.nents, DMA_TO_DEVICE);
+       if (!tx_sglen)
+               goto err_tx_sgmap;
+
+       /* Send both scatterlists */
+       rxdesc = dmaengine_prep_slave_sg(rxchan,
+                                     pl022->sgt_rx.sgl,
+                                     rx_sglen,
+                                     DMA_DEV_TO_MEM,
+                                     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+       if (!rxdesc)
+               goto err_rxdesc;
+
+       txdesc = dmaengine_prep_slave_sg(txchan,
+                                     pl022->sgt_tx.sgl,
+                                     tx_sglen,
+                                     DMA_MEM_TO_DEV,
+                                     DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+       if (!txdesc)
+               goto err_txdesc;
+
+       /* Put the callback on the RX transfer only, that should finish last */
+       rxdesc->callback = dma_callback;
+       rxdesc->callback_param = pl022;
+
+       /* Submit and fire RX and TX with TX last so we're ready to read! */
+       dmaengine_submit(rxdesc);
+       dmaengine_submit(txdesc);
+       dma_async_issue_pending(rxchan);
+       dma_async_issue_pending(txchan);
+       pl022->dma_running = true;
+
+       return 0;
+
+err_txdesc:
+       dmaengine_terminate_all(txchan);
+err_rxdesc:
+       dmaengine_terminate_all(rxchan);
+       dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
+                    pl022->sgt_tx.nents, DMA_TO_DEVICE);
+err_tx_sgmap:
+       dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
+                    pl022->sgt_tx.nents, DMA_FROM_DEVICE);
+err_rx_sgmap:
+       sg_free_table(&pl022->sgt_tx);
+err_alloc_tx_sg:
+       sg_free_table(&pl022->sgt_rx);
+err_alloc_rx_sg:
+       return -ENOMEM;
+}
+
+static int pl022_dma_probe(struct pl022 *pl022)
+{
+       dma_cap_mask_t mask;
+
+       /* Try to acquire a generic DMA engine slave channel */
+       dma_cap_zero(mask);
+       dma_cap_set(DMA_SLAVE, mask);
+       /*
+        * We need both RX and TX channels to do DMA, else do none
+        * of them.
+        */
+       pl022->dma_rx_channel = dma_request_channel(mask,
+                                           pl022->master_info->dma_filter,
+                                           pl022->master_info->dma_rx_param);
+       if (!pl022->dma_rx_channel) {
+               dev_dbg(&pl022->dev->dev, "no RX DMA channel!\n");
+               goto err_no_rxchan;
+       }
+
+       pl022->dma_tx_channel = dma_request_channel(mask,
+                                           pl022->master_info->dma_filter,
+                                           pl022->master_info->dma_tx_param);
+       if (!pl022->dma_tx_channel) {
+               dev_dbg(&pl022->dev->dev, "no TX DMA channel!\n");
+               goto err_no_txchan;
+       }
+
+       pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
+       if (!pl022->dummypage) {
+               dev_dbg(&pl022->dev->dev, "no DMA dummypage!\n");
+               goto err_no_dummypage;
+       }
+
+       dev_info(&pl022->dev->dev, "setup for DMA on RX %s, TX %s\n",
+                dma_chan_name(pl022->dma_rx_channel),
+                dma_chan_name(pl022->dma_tx_channel));
+
+       return 0;
+
+err_no_dummypage:
+       dma_release_channel(pl022->dma_tx_channel);
+err_no_txchan:
+       dma_release_channel(pl022->dma_rx_channel);
+       pl022->dma_rx_channel = NULL;
+err_no_rxchan:
+       dev_err(&pl022->dev->dev,
+                       "Failed to work in dma mode, work without dma!\n");
+       return -ENODEV;
+}
+
+static void terminate_dma(struct pl022 *pl022)
+{
+       struct dma_chan *rxchan = pl022->dma_rx_channel;
+       struct dma_chan *txchan = pl022->dma_tx_channel;
+
+       dmaengine_terminate_all(rxchan);
+       dmaengine_terminate_all(txchan);
+       unmap_free_dma_scatter(pl022);
+       pl022->dma_running = false;
+}
+
+static void pl022_dma_remove(struct pl022 *pl022)
+{
+       if (pl022->dma_running)
+               terminate_dma(pl022);
+       if (pl022->dma_tx_channel)
+               dma_release_channel(pl022->dma_tx_channel);
+       if (pl022->dma_rx_channel)
+               dma_release_channel(pl022->dma_rx_channel);
+       kfree(pl022->dummypage);
+}
+
+#else
+static inline int configure_dma(struct pl022 *pl022)
+{
+       return -ENODEV;
+}
+
+static inline int pl022_dma_probe(struct pl022 *pl022)
+{
+       return 0;
+}
+
+static inline void pl022_dma_remove(struct pl022 *pl022)
+{
+}
+#endif
+
+/**
+ * pl022_interrupt_handler - Interrupt handler for SSP controller
+ *
+ * This function handles interrupts generated for an interrupt based transfer.
+ * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
+ * current message's state as STATE_ERROR and schedule the tasklet
+ * pump_transfers which will do the postprocessing of the current message by
+ * calling giveback(). Otherwise it reads data from RX FIFO till there is no
+ * more data, and writes data in TX FIFO till it is not full. If we complete
+ * the transfer we move to the next transfer and schedule the tasklet.
+ */
+static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
+{
+       struct pl022 *pl022 = dev_id;
+       struct spi_message *msg = pl022->cur_msg;
+       u16 irq_status = 0;
+       u16 flag = 0;
+
+       if (unlikely(!msg)) {
+               dev_err(&pl022->dev->dev,
+                       "bad message state in interrupt handler");
+               /* Never fail */
+               return IRQ_HANDLED;
+       }
+
+       /* Read the Interrupt Status Register */
+       irq_status = readw(SSP_MIS(pl022->virtbase));
+
+       if (unlikely(!irq_status))
+               return IRQ_NONE;
+
+       /*
+        * This handles the FIFO interrupts, the timeout
+        * interrupts are flatly ignored, they cannot be
+        * trusted.
+        */
+       if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
+               /*
+                * Overrun interrupt - bail out since our Data has been
+                * corrupted
+                */
+               dev_err(&pl022->dev->dev, "FIFO overrun\n");
+               if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
+                       dev_err(&pl022->dev->dev,
+                               "RXFIFO is full\n");
+               if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_TNF)
+                       dev_err(&pl022->dev->dev,
+                               "TXFIFO is full\n");
+
+               /*
+                * Disable and clear interrupts, disable SSP,
+                * mark message with bad status so it can be
+                * retried.
+                */
+               writew(DISABLE_ALL_INTERRUPTS,
+                      SSP_IMSC(pl022->virtbase));
+               writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+               writew((readw(SSP_CR1(pl022->virtbase)) &
+                       (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
+               msg->state = STATE_ERROR;
+
+               /* Schedule message queue handler */
+               tasklet_schedule(&pl022->pump_transfers);
+               return IRQ_HANDLED;
+       }
+
+       readwriter(pl022);
+
+       if ((pl022->tx == pl022->tx_end) && (flag == 0)) {
+               flag = 1;
+               /* Disable Transmit interrupt, enable receive interrupt */
+               writew((readw(SSP_IMSC(pl022->virtbase)) &
+                      ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
+                      SSP_IMSC(pl022->virtbase));
+       }
+
+       /*
+        * Since all transactions must write as much as shall be read,
+        * we can conclude the entire transaction once RX is complete.
+        * At this point, all TX will always be finished.
+        */
+       if (pl022->rx >= pl022->rx_end) {
+               writew(DISABLE_ALL_INTERRUPTS,
+                      SSP_IMSC(pl022->virtbase));
+               writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
+               if (unlikely(pl022->rx > pl022->rx_end)) {
+                       dev_warn(&pl022->dev->dev, "read %u surplus bytes (did 
you request an odd number of bytes on a 16bit bus?)\n",
+                                (u32) (pl022->rx - pl022->rx_end));
+               }
+               /* Update total bytes transferred */
+               msg->actual_length += pl022->cur_transfer->len;
+               if (pl022->cur_transfer->cs_change)
+                       pl022->cur_chip->
+                               cs_control(SSP_CHIP_DESELECT);
+               /* Move to next transfer */
+               msg->state = next_transfer(pl022);
+               tasklet_schedule(&pl022->pump_transfers);
+               return IRQ_HANDLED;
+       }
+
+       return IRQ_HANDLED;
+}
+
+/**
+ * This sets up the pointers to memory for the next message to
+ * send out on the SPI bus.
+ */
+static int set_up_next_transfer(struct pl022 *pl022,
+                               struct spi_transfer *transfer)
+{
+       int residue;
+
+       /* Sanity check the message for this bus width */
+       residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
+       if (unlikely(residue != 0)) {
+               dev_err(&pl022->dev->dev,
+                       "message of %u bytes to transmit but the current "
+                       "chip bus has a data width of %u bytes!\n",
+                       pl022->cur_transfer->len,
+                       pl022->cur_chip->n_bytes);
+               dev_err(&pl022->dev->dev, "skipping this message\n");
+               return -EIO;
+       }
+       pl022->tx = (void *)transfer->tx_buf;
+       pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
+       pl022->rx = (void *)transfer->rx_buf;
+       pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
+       pl022->write =
+           pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
+       pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
+       return 0;
+}
+
+/**
+ * pump_transfers - Tasklet function which schedules next transfer
+ * when running in interrupt or DMA transfer mode.
+ * @data: SSP driver private data structure
+ *
+ */
+static void pump_transfers(unsigned long data)
+{
+       struct pl022 *pl022 = (struct pl022 *) data;
+       struct spi_message *message = NULL;
+       struct spi_transfer *transfer = NULL;
+       struct spi_transfer *previous = NULL;
+
+       /* Get current state information */
+       message = pl022->cur_msg;
+       transfer = pl022->cur_transfer;
+
+       /* Handle for abort */
+       if (message->state == STATE_ERROR) {
+               message->status = -EIO;
+               giveback(pl022);
+               return;
+       }
+
+       /* Handle end of message */
+       if (message->state == STATE_DONE) {
+               message->status = 0;
+               giveback(pl022);
+               return;
+       }
+
+       /* Delay if requested at end of transfer before CS change */
+       if (message->state == STATE_RUNNING) {
+               previous = list_entry(transfer->transfer_list.prev,
+                                       struct spi_transfer,
+                                       transfer_list);
+               if (previous->delay_usecs)
+                       /*
+                        * FIXME: This runs in interrupt context.
+                        * Is this really smart?
+                        */
+                       udelay(previous->delay_usecs);
+
+               /* Reselect chip select only if cs_change was requested */
+               if (previous->cs_change)
+                       pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
+       } else {
+               /* STATE_START */
+               message->state = STATE_RUNNING;
+       }
+
+       if (set_up_next_transfer(pl022, transfer)) {
+               message->state = STATE_ERROR;
+               message->status = -EIO;
+               giveback(pl022);
+               return;
+       }
+       /* Flush the FIFOs and let's go! */
+       flush(pl022);
+
+       if (pl022->cur_chip->enable_dma) {
+               if (configure_dma(pl022)) {
+                       dev_dbg(&pl022->dev->dev,
+                               "configuration of DMA failed, fall back to 
interrupt mode\n");
+                       goto err_config_dma;
+               }
+               return;
+       }
+
+err_config_dma:
+       /* enable all interrupts except RX */
+       writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM,
+              SSP_IMSC(pl022->virtbase));
+}
+
+static void do_interrupt_dma_transfer(struct pl022 *pl022)
+{
+       /*
+        * Default is to enable all interrupts except RX -
+        * this will be enabled once TX is complete
+        */
+       u32 irqflags = ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM;
+
+       /* Enable target chip, if not already active */
+       if (!pl022->next_msg_cs_active)
+               pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
+
+       if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
+               /* Error path */
+               pl022->cur_msg->state = STATE_ERROR;
+               pl022->cur_msg->status = -EIO;
+               giveback(pl022);
+               return;
+       }
+       /* If we're using DMA, set up DMA here */
+       if (pl022->cur_chip->enable_dma) {
+               /* Configure DMA transfer */
+               if (configure_dma(pl022)) {
+                       dev_dbg(&pl022->dev->dev,
+                               "configuration of DMA failed, fall back to 
interrupt mode\n");
+                       goto err_config_dma;
+               }
+               /* Disable interrupts in DMA mode, IRQ from DMA controller */
+               irqflags = DISABLE_ALL_INTERRUPTS;
+       }
+err_config_dma:
+       /* Enable SSP, turn on interrupts */
+       writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
+              SSP_CR1(pl022->virtbase));
+       writew(irqflags, SSP_IMSC(pl022->virtbase));
+}
+
+static void do_polling_transfer(struct pl022 *pl022)
+{
+       struct spi_message *message = NULL;
+       struct spi_transfer *transfer = NULL;
+       struct spi_transfer *previous = NULL;
+       struct chip_data *chip;
+       unsigned long time, timeout;
+
+       chip = pl022->cur_chip;
+       message = pl022->cur_msg;
+
+       while (message->state != STATE_DONE) {
+               /* Handle for abort */
+               if (message->state == STATE_ERROR)
+                       break;
+               transfer = pl022->cur_transfer;
+
+               /* Delay if requested at end of transfer */
+               if (message->state == STATE_RUNNING) {
+                       previous =
+                           list_entry(transfer->transfer_list.prev,
+                                      struct spi_transfer, transfer_list);
+                       if (previous->delay_usecs)
+                               udelay(previous->delay_usecs);
+                       if (previous->cs_change)
+                               pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
+               } else {
+                       /* STATE_START */
+                       message->state = STATE_RUNNING;
+                       if (!pl022->next_msg_cs_active)
+                               pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
+               }
+
+               /* Configuration Changing Per Transfer */
+               if (set_up_next_transfer(pl022, transfer)) {
+                       /* Error path */
+                       message->state = STATE_ERROR;
+                       break;
+               }
+               /* Flush FIFOs and enable SSP */
+               flush(pl022);
+               writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
+                      SSP_CR1(pl022->virtbase));
+
+               dev_dbg(&pl022->dev->dev, "polling transfer ongoing ...\n");
+
+               timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
+               while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
+                       time = jiffies;
+                       readwriter(pl022);
+                       if (time_after(time, timeout)) {
+                               dev_warn(&pl022->dev->dev,
+                               "%s: timeout!\n", __func__);
+                               message->state = STATE_ERROR;
+                               goto out;
+                       }
+                       cpu_relax();
+               }
+
+               /* Update total byte transferred */
+               message->actual_length += pl022->cur_transfer->len;
+               if (pl022->cur_transfer->cs_change)
+                       pl022->cur_chip->cs_control(SSP_CHIP_DESELECT);
+               /* Move to next transfer */
+               message->state = next_transfer(pl022);
+       }
+out:
+       /* Handle end of message */
+       if (message->state == STATE_DONE)
+               message->status = 0;
+       else
+               message->status = -EIO;
+
+       giveback(pl022);
+}
+
+static int pl022_transfer_one_message(struct spi_master *master,
+                                     struct spi_message *msg)
+{
+       struct pl022 *pl022 = spi_master_get_devdata(master);
+
+       /* Initial message state */
+       pl022->cur_msg = msg;
+       msg->state = STATE_START;
+
+       pl022->cur_transfer = list_entry(msg->transfers.next,
+                                        struct spi_transfer, transfer_list);
+
+       /* Setup the SPI using the per chip configuration */
+       pl022->cur_chip = spi_get_ctldata(msg->spi);
+
+       restore_state(pl022);
+       flush(pl022);
+
+       if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
+               do_polling_transfer(pl022);
+       else
+               do_interrupt_dma_transfer(pl022);
+
+       return 0;
+}
+
+static int pl022_prepare_transfer_hardware(struct spi_master *master)
+{
+       struct pl022 *pl022 = spi_master_get_devdata(master);
+
+       /*
+        * Just make sure we have all we need to run the transfer by syncing
+        * with the runtime PM framework.
+        */
+       pm_runtime_get_sync(&pl022->dev->dev);
+       return 0;
+}
+
+static int pl022_unprepare_transfer_hardware(struct spi_master *master)
+{
+       struct pl022 *pl022 = spi_master_get_devdata(master);
+
+       /* nothing more to do - disable spi/ssp and power off */
+       writew((readw(SSP_CR1(pl022->virtbase)) &
+               (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
+
+       if (pl022->master_info->autosuspend_delay > 0) {
+               pm_runtime_mark_last_busy(&pl022->dev->dev);
+               pm_runtime_put_autosuspend(&pl022->dev->dev);
+       } else {
+               pm_runtime_put(&pl022->dev->dev);
+       }
+
+       return 0;
+}
+
+static int verify_controller_parameters(struct pl022 *pl022,
+                               struct pl022_config_chip const *chip_info)
+{
+       if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
+           || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
+               dev_err(&pl022->dev->dev,
+                       "interface is configured incorrectly\n");
+               return -EINVAL;
+       }
+       if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
+           (!pl022->vendor->unidir)) {
+               dev_err(&pl022->dev->dev,
+                       "unidirectional mode not supported in this "
+                       "hardware version\n");
+               return -EINVAL;
+       }
+       if ((chip_info->hierarchy != SSP_MASTER)
+           && (chip_info->hierarchy != SSP_SLAVE)) {
+               dev_err(&pl022->dev->dev,
+                       "hierarchy is configured incorrectly\n");
+               return -EINVAL;
+       }
+       if ((chip_info->com_mode != INTERRUPT_TRANSFER)
+           && (chip_info->com_mode != DMA_TRANSFER)
+           && (chip_info->com_mode != POLLING_TRANSFER)) {
+               dev_err(&pl022->dev->dev,
+                       "Communication mode is configured incorrectly\n");
+               return -EINVAL;
+       }
+       switch (chip_info->rx_lev_trig) {
+       case SSP_RX_1_OR_MORE_ELEM:
+       case SSP_RX_4_OR_MORE_ELEM:
+       case SSP_RX_8_OR_MORE_ELEM:
+               /* These are always OK, all variants can handle this */
+               break;
+       case SSP_RX_16_OR_MORE_ELEM:
+               if (pl022->vendor->fifodepth < 16) {
+                       dev_err(&pl022->dev->dev,
+                       "RX FIFO Trigger Level is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               break;
+       case SSP_RX_32_OR_MORE_ELEM:
+               if (pl022->vendor->fifodepth < 32) {
+                       dev_err(&pl022->dev->dev,
+                       "RX FIFO Trigger Level is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               break;
+       default:
+               dev_err(&pl022->dev->dev,
+                       "RX FIFO Trigger Level is configured incorrectly\n");
+               return -EINVAL;
+       }
+       switch (chip_info->tx_lev_trig) {
+       case SSP_TX_1_OR_MORE_EMPTY_LOC:
+       case SSP_TX_4_OR_MORE_EMPTY_LOC:
+       case SSP_TX_8_OR_MORE_EMPTY_LOC:
+               /* These are always OK, all variants can handle this */
+               break;
+       case SSP_TX_16_OR_MORE_EMPTY_LOC:
+               if (pl022->vendor->fifodepth < 16) {
+                       dev_err(&pl022->dev->dev,
+                       "TX FIFO Trigger Level is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               break;
+       case SSP_TX_32_OR_MORE_EMPTY_LOC:
+               if (pl022->vendor->fifodepth < 32) {
+                       dev_err(&pl022->dev->dev,
+                       "TX FIFO Trigger Level is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               break;
+       default:
+               dev_err(&pl022->dev->dev,
+                       "TX FIFO Trigger Level is configured incorrectly\n");
+               return -EINVAL;
+       }
+       if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
+               if ((chip_info->ctrl_len < SSP_BITS_4)
+                   || (chip_info->ctrl_len > SSP_BITS_32)) {
+                       dev_err(&pl022->dev->dev,
+                               "CTRL LEN is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
+                   && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
+                       dev_err(&pl022->dev->dev,
+                               "Wait State is configured incorrectly\n");
+                       return -EINVAL;
+               }
+               /* Half duplex is only available in the ST Micro version */
+               if (pl022->vendor->extended_cr) {
+                       if ((chip_info->duplex !=
+                            SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
+                           && (chip_info->duplex !=
+                               SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
+                               dev_err(&pl022->dev->dev,
+                                       "Microwire duplex mode is configured 
incorrectly\n");
+                               return -EINVAL;
+                       }
+               } else {
+                       if (chip_info->duplex !=
+                           SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
+                               dev_err(&pl022->dev->dev,
+                                       "Microwire half duplex mode requested,"
+                                       " but this is only available in the"
+                                       " ST version of PL022\n");
+                       return -EINVAL;
+               }
+       }
+       return 0;
+}
+
+static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
+{
+       return rate / (cpsdvsr * (1 + scr));
+}
+
+static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
+                                   ssp_clock_params * clk_freq)
+{
+       /* Lets calculate the frequency parameters */
+       u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
+       u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
+               best_scr = 0, tmp, found = 0;
+
+       rate = clk_get_rate(pl022->clk);
+       /* cpsdvscr = 2 & scr 0 */
+       max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
+       /* cpsdvsr = 254 & scr = 255 */
+       min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
+
+       if (freq > max_tclk)
+               dev_warn(&pl022->dev->dev,
+                       "Max speed that can be programmed is %d Hz, you 
requested %d\n",
+                       max_tclk, freq);
+
+       if (freq < min_tclk) {
+               dev_err(&pl022->dev->dev,
+                       "Requested frequency: %d Hz is less than minimum 
possible %d Hz\n",
+                       freq, min_tclk);
+               return -EINVAL;
+       }
+
+       /*
+        * best_freq will give closest possible available rate (<= requested
+        * freq) for all values of scr & cpsdvsr.
+        */
+       while ((cpsdvsr <= CPSDVR_MAX) && !found) {
+               while (scr <= SCR_MAX) {
+                       tmp = spi_rate(rate, cpsdvsr, scr);
+
+                       if (tmp > freq) {
+                               /* we need lower freq */
+                               scr++;
+                               continue;
+                       }
+
+                       /*
+                        * If found exact value, mark found and break.
+                        * If found more closer value, update and break.
+                        */
+                       if (tmp > best_freq) {
+                               best_freq = tmp;
+                               best_cpsdvsr = cpsdvsr;
+                               best_scr = scr;
+
+                               if (tmp == freq)
+                                       found = 1;
+                       }
+                       /*
+                        * increased scr will give lower rates, which are not
+                        * required
+                        */
+                       break;
+               }
+               cpsdvsr += 2;
+               scr = SCR_MIN;
+       }
+
+       WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz 
rate\n",
+                       freq);
+
+       clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
+       clk_freq->scr = (u8) (best_scr & 0xFF);
+       dev_dbg(&pl022->dev->dev,
+               "SSP Target Frequency is: %u, Effective Frequency is %u\n",
+               freq, best_freq);
+       dev_dbg(&pl022->dev->dev, "SSP cpsdvsr = %d, scr = %d\n",
+               clk_freq->cpsdvsr, clk_freq->scr);
+
+       return 0;
+}
+
+/*
+ * A piece of default chip info unless the platform
+ * supplies it.
+ */
+static const struct pl022_config_chip pl022_default_chip_info = {
+       .com_mode = POLLING_TRANSFER,
+       .iface = SSP_INTERFACE_MOTOROLA_SPI,
+       .hierarchy = SSP_SLAVE,
+       .slave_tx_disable = DO_NOT_DRIVE_TX,
+       .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
+       .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
+       .ctrl_len = SSP_BITS_8,
+       .wait_state = SSP_MWIRE_WAIT_ZERO,
+       .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
+       .cs_control = null_cs_control,
+};
+
+/**
+ * pl022_setup - setup function registered to SPI master framework
+ * @spi: spi device which is requesting setup
+ *
+ * This function is registered to the SPI framework for this SPI master
+ * controller. If it is the first time when setup is called by this device,
+ * this function will initialize the runtime state for this chip and save
+ * the same in the device structure. Else it will update the runtime info
+ * with the updated chip info. Nothing is really being written to the
+ * controller hardware here, that is not done until the actual transfer
+ * commence.
+ */
+static int pl022_setup(struct spi_device *spi)
+{
+       struct pl022_config_chip const *chip_info;
+       struct chip_data *chip;
+       struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
+       int status = 0;
+       struct pl022 *pl022 = spi_master_get_devdata(spi->master);
+       unsigned int bits = spi->bits_per_word;
+       u32 tmp;
+
+       if (!spi->max_speed_hz)
+               return -EINVAL;
+
+       /* Get controller_state if one is supplied */
+       chip = spi_get_ctldata(spi);
+
+       if (chip == NULL) {
+               chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
+               if (!chip) {
+                       dev_err(&spi->dev,
+                               "cannot allocate controller state\n");
+                       return -ENOMEM;
+               }
+               dev_dbg(&spi->dev,
+                       "allocated memory for controller's runtime state\n");
+       }
+
+       /* Get controller data if one is supplied */
+       chip_info = spi->controller_data;
+
+       if (chip_info == NULL) {
+               chip_info = &pl022_default_chip_info;
+               /* spi_board_info.controller_data not is supplied */
+               dev_dbg(&spi->dev,
+                       "using default controller_data settings\n");
+       } else
+               dev_dbg(&spi->dev,
+                       "using user supplied controller_data settings\n");
+
+       /*
+        * We can override with custom divisors, else we use the board
+        * frequency setting
+        */
+       if ((0 == chip_info->clk_freq.cpsdvsr)
+           && (0 == chip_info->clk_freq.scr)) {
+               status = calculate_effective_freq(pl022,
+                                                 spi->max_speed_hz,
+                                                 &clk_freq);
+               if (status < 0)
+                       goto err_config_params;
+       } else {
+               memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
+               if ((clk_freq.cpsdvsr % 2) != 0)
+                       clk_freq.cpsdvsr =
+                               clk_freq.cpsdvsr - 1;
+       }
+       if ((clk_freq.cpsdvsr < CPSDVR_MIN)
+           || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
+               status = -EINVAL;
+               dev_err(&spi->dev,
+                       "cpsdvsr is configured incorrectly\n");
+               goto err_config_params;
+       }
+
+       status = verify_controller_parameters(pl022, chip_info);
+       if (status) {
+               dev_err(&spi->dev, "controller data is incorrect");
+               goto err_config_params;
+       }
+
+       pl022->rx_lev_trig = chip_info->rx_lev_trig;
+       pl022->tx_lev_trig = chip_info->tx_lev_trig;
+
+       /* Now set controller state based on controller data */
+       chip->xfer_type = chip_info->com_mode;
+       if (!chip_info->cs_control) {
+               chip->cs_control = null_cs_control;
+               dev_warn(&spi->dev,
+                        "chip select function is NULL for this chip\n");
+       } else
+               chip->cs_control = chip_info->cs_control;
+
+       /* Check bits per word with vendor specific range */
+       if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
+               status = -ENOTSUPP;
+               dev_err(&spi->dev, "illegal data size for this controller!\n");
+               dev_err(&spi->dev, "This controller can only handle 4 <= n <= 
%d bit words\n",
+                               pl022->vendor->max_bpw);
+               goto err_config_params;
+       } else if (bits <= 8) {
+               dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
+               chip->n_bytes = 1;
+               chip->read = READING_U8;
+               chip->write = WRITING_U8;
+       } else if (bits <= 16) {
+               dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
+               chip->n_bytes = 2;
+               chip->read = READING_U16;
+               chip->write = WRITING_U16;
+       } else {
+               dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
+               chip->n_bytes = 4;
+               chip->read = READING_U32;
+               chip->write = WRITING_U32;
+       }
+
+       /* Now Initialize all register settings required for this chip */
+       chip->cr0 = 0;
+       chip->cr1 = 0;
+       chip->dmacr = 0;
+       chip->cpsr = 0;
+       if ((chip_info->com_mode == DMA_TRANSFER)
+           && ((pl022->master_info)->enable_dma)) {
+               chip->enable_dma = true;
+               dev_dbg(&spi->dev, "DMA mode set in controller state\n");
+               SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
+                              SSP_DMACR_MASK_RXDMAE, 0);
+               SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
+                              SSP_DMACR_MASK_TXDMAE, 1);
+       } else {
+               chip->enable_dma = false;
+               dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
+               SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
+                              SSP_DMACR_MASK_RXDMAE, 0);
+               SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
+                              SSP_DMACR_MASK_TXDMAE, 1);
+       }
+
+       chip->cpsr = clk_freq.cpsdvsr;
+
+       /* Special setup for the ST micro extended control registers */
+       if (pl022->vendor->extended_cr) {
+               u32 etx;
+
+               if (pl022->vendor->pl023) {
+                       /* These bits are only in the PL023 */
+                       SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
+                                      SSP_CR1_MASK_FBCLKDEL_ST, 13);
+               } else {
+                       /* These bits are in the PL022 but not PL023 */
+                       SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
+                                      SSP_CR0_MASK_HALFDUP_ST, 5);
+                       SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
+                                      SSP_CR0_MASK_CSS_ST, 16);
+                       SSP_WRITE_BITS(chip->cr0, chip_info->iface,
+                                      SSP_CR0_MASK_FRF_ST, 21);
+                       SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
+                                      SSP_CR1_MASK_MWAIT_ST, 6);
+               }
+               SSP_WRITE_BITS(chip->cr0, bits - 1,
+                              SSP_CR0_MASK_DSS_ST, 0);
+
+               if (spi->mode & SPI_LSB_FIRST) {
+                       tmp = SSP_RX_LSB;
+                       etx = SSP_TX_LSB;
+               } else {
+                       tmp = SSP_RX_MSB;
+                       etx = SSP_TX_MSB;
+               }
+               SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
+               SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
+               SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
+                              SSP_CR1_MASK_RXIFLSEL_ST, 7);
+               SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
+                              SSP_CR1_MASK_TXIFLSEL_ST, 10);
+       } else {
+               SSP_WRITE_BITS(chip->cr0, bits - 1,
+                              SSP_CR0_MASK_DSS, 0);
+               SSP_WRITE_BITS(chip->cr0, chip_info->iface,
+                              SSP_CR0_MASK_FRF, 4);
+       }
+
+       /* Stuff that is common for all versions */
+       if (spi->mode & SPI_CPOL)
+               tmp = SSP_CLK_POL_IDLE_HIGH;
+       else
+               tmp = SSP_CLK_POL_IDLE_LOW;
+       SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
+
+       if (spi->mode & SPI_CPHA)
+               tmp = SSP_CLK_SECOND_EDGE;
+       else
+               tmp = SSP_CLK_FIRST_EDGE;
+       SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
+
+       SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
+       /* Loopback is available on all versions except PL023 */
+       if (pl022->vendor->loopback) {
+               if (spi->mode & SPI_LOOP)
+                       tmp = LOOPBACK_ENABLED;
+               else
+                       tmp = LOOPBACK_DISABLED;
+               SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
+       }
+       SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
+       SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
+       SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
+               3);
+
+       /* Save controller_state */
+       spi_set_ctldata(spi, chip);
+       return status;
+ err_config_params:
+       spi_set_ctldata(spi, NULL);
+       kfree(chip);
+       return status;
+}
+
+/**
+ * pl022_cleanup - cleanup function registered to SPI master framework
+ * @spi: spi device which is requesting cleanup
+ *
+ * This function is registered to the SPI framework for this SPI master
+ * controller. It will free the runtime state of chip.
+ */
+static void pl022_cleanup(struct spi_device *spi)
+{
+       struct chip_data *chip = spi_get_ctldata(spi);
+
+       spi_set_ctldata(spi, NULL);
+       kfree(chip);
+}
+
+static int pl022_probe(
+       struct device *dev,
+       const struct vendor_data *vendor,
+       struct resource *res,
+       int irq, struct pl022 **retpl022)
+{
+       struct pl022_ssp_controller *platform_info = dev->platform_data;
+       struct spi_master *master;
+       struct pl022 *pl022 = NULL;     /*Data for this driver */
+       int status = 0;
+
+       if (platform_info == NULL) {
+               dev_err(dev, "probe - no platform data supplied\n");
+               status = -ENODEV;
+               goto err_no_pdata;
+       }
+
+       /* Allocate master with space for data */
+       master = spi_alloc_master(dev, sizeof(struct pl022));
+       if (master == NULL) {
+               dev_err(dev, "probe - cannot alloc SPI master\n");
+               status = -ENOMEM;
+               goto err_no_master;
+       }
+
+       pl022 = spi_master_get_devdata(master);
+       pl022->master = master;
+       pl022->master_info = platform_info;
+       pl022->vendor = vendor;
+
+       /*
+        * Bus Number Which has been Assigned to this SSP controller
+        * on this board
+        */
+       master->bus_num = platform_info->bus_id;
+       master->num_chipselect = platform_info->num_chipselect;
+       master->cleanup = pl022_cleanup;
+       master->setup = pl022_setup;
+       master->prepare_transfer_hardware = pl022_prepare_transfer_hardware;
+       master->transfer_one_message = pl022_transfer_one_message;
+       master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
+       master->rt = platform_info->rt;
+
+       /*
+        * Supports mode 0-3, loopback, and active low CS. Transfers are
+        * always MS bit first on the original pl022.
+        */
+       master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
+       if (pl022->vendor->extended_cr)
+               master->mode_bits |= SPI_LSB_FIRST;
+
+       dev_dbg(dev, "BUSNO: %d\n", master->bus_num);
+
+       if (!request_mem_region(res->start, resource_size(res),
+                       dev->driver->name))
+               goto err_no_ioregion;
+
+       pl022->phybase = res->start;
+       pl022->virtbase = ioremap(res->start, resource_size(res));
+       if (pl022->virtbase == NULL) {
+               status = -ENOMEM;
+               goto err_no_ioremap;
+       }
+       pr_info("pl022: mapped registers from 0x%llx to %p\n",
+               res->start, pl022->virtbase);
+
+       pl022->clk = clk_get(dev, NULL);
+       if (IS_ERR(pl022->clk)) {
+               status = PTR_ERR(pl022->clk);
+               dev_err(dev, "could not retrieve SSP/SPI bus clock\n");
+               goto err_no_clk;
+       }
+
+       status = clk_prepare(pl022->clk);
+       if (status) {
+               dev_err(dev, "could not prepare SSP/SPI bus clock\n");
+               goto  err_clk_prep;
+       }
+
+       status = clk_enable(pl022->clk);
+       if (status) {
+               dev_err(dev, "could not enable SSP/SPI bus clock\n");
+               goto err_no_clk_en;
+       }
+
+       /* Initialize transfer pump */
+       tasklet_init(&pl022->pump_transfers, pump_transfers,
+                    (unsigned long)pl022);
+
+       /* Disable SSP */
+       writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
+              SSP_CR1(pl022->virtbase));
+       load_ssp_default_config(pl022);
+
+       status = request_irq(irq, pl022_interrupt_handler, 0, "pl022",
+                            pl022);
+       if (status < 0) {
+               dev_err(dev, "probe - cannot get IRQ (%d)\n", status);
+               goto err_no_irq;
+       }
+
+       /* Get DMA channels */
+       if (platform_info->enable_dma) {
+               status = pl022_dma_probe(pl022);
+               if (status != 0)
+                       platform_info->enable_dma = 0;
+       }
+
+       /* Register with the SPI framework */
+       dev_set_drvdata(dev, pl022);
+       status = spi_register_master(master);
+       if (status != 0) {
+               dev_err(dev,
+                       "probe - problem registering spi master\n");
+               goto err_spi_register;
+       }
+       dev_dbg(dev, "probe succeeded\n");
+
+       if (retpl022)
+               *retpl022 = pl022;
+
+       /* let runtime pm put suspend */
+       if (platform_info->autosuspend_delay > 0) {
+               dev_info(dev,
+                       "will use autosuspend for runtime pm, delay %dms\n",
+                       platform_info->autosuspend_delay);
+               pm_runtime_set_autosuspend_delay(dev,
+                       platform_info->autosuspend_delay);
+               pm_runtime_use_autosuspend(dev);
+               pm_runtime_put_autosuspend(dev);
+       } else {
+               pm_runtime_put(dev);
+       }
+       return 0;
+
+ err_spi_register:
+       if (platform_info->enable_dma)
+               pl022_dma_remove(pl022);
+
+       free_irq(irq, pl022);
+ err_no_irq:
+       clk_disable(pl022->clk);
+ err_no_clk_en:
+       clk_unprepare(pl022->clk);
+ err_clk_prep:
+       clk_put(pl022->clk);
+ err_no_clk:
+       iounmap(pl022->virtbase);
+ err_no_ioremap:
+       release_mem_region(res->start, resource_size(res));
+ err_no_ioregion:
+       spi_master_put(master);
+ err_no_master:
+ err_no_pdata:
+       return status;
+}
+
+static int pl022_remove(struct device *dev, struct resource *res, int irq)
+{
+       struct pl022 *pl022 = dev_get_drvdata(dev);
+
+       if (!pl022)
+               return 0;
+
+       /*
+        * undo pm_runtime_put() in probe.  I assume that we're not
+        * accessing the primecell here.
+        */
+       pm_runtime_get_noresume(dev);
+
+       load_ssp_default_config(pl022);
+       if (pl022->master_info->enable_dma)
+               pl022_dma_remove(pl022);
+
+       free_irq(irq, pl022);
+       clk_disable(pl022->clk);
+       clk_unprepare(pl022->clk);
+       clk_put(pl022->clk);
+       iounmap(pl022->virtbase);
+       release_mem_region(res->start, resource_size(res));
+       tasklet_disable(&pl022->pump_transfers);
+       spi_unregister_master(pl022->master);
+       spi_master_put(pl022->master);
+       dev_set_drvdata(dev, NULL);
+       return 0;
+}
+
+#ifdef CONFIG_SUSPEND
+static int pl022_suspend(struct device *dev)
+{
+       struct pl022 *pl022 = dev_get_drvdata(dev);
+       int ret;
+
+       ret = spi_master_suspend(pl022->master);
+       if (ret) {
+               dev_warn(dev, "cannot suspend master\n");
+               return ret;
+       }
+
+       dev_dbg(dev, "suspended\n");
+       return 0;
+}
+
+static int pl022_resume(struct device *dev)
+{
+       struct pl022 *pl022 = dev_get_drvdata(dev);
+       int ret;
+
+       /* Start the queue running */
+       ret = spi_master_resume(pl022->master);
+       if (ret)
+               dev_err(dev, "problem starting queue (%d)\n", ret);
+       else
+               dev_dbg(dev, "resumed\n");
+
+       return ret;
+}
+#endif /* CONFIG_PM */
+
+#ifdef CONFIG_PM_RUNTIME
+static int pl022_runtime_suspend(struct device *dev)
+{
+       struct pl022 *pl022 = dev_get_drvdata(dev);
+
+       clk_disable(pl022->clk);
+
+       return 0;
+}
+
+static int pl022_runtime_resume(struct device *dev)
+{
+       struct pl022 *pl022 = dev_get_drvdata(dev);
+
+       clk_enable(pl022->clk);
+
+       return 0;
+}
+#endif
+
+static const struct dev_pm_ops pl022_dev_pm_ops = {
+       SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
+       SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
+};
+
+static struct vendor_data vendor_arm = {
+       .fifodepth = 8,
+       .max_bpw = 16,
+       .unidir = false,
+       .extended_cr = false,
+       .pl023 = false,
+       .loopback = true,
+};
+
+static void __iomem *pl022_virtbase;
+static void __acp_spi_cs_control(u32 control, int cs)
+{
+       if (control == SSP_CHIP_SELECT)
+               writel(
+                       readl(SSP_CSR(pl022_virtbase)) &
+                               ~(1 << cs),
+                       SSP_CSR(pl022_virtbase));
+       else if (control == SSP_CHIP_DESELECT)
+               writel(
+                       readl(SSP_CSR(pl022_virtbase)) |
+                               (1 << cs),
+                       SSP_CSR(pl022_virtbase));
+}
+
+#define DECLARE_PL022_CS_FUN(x) \
+static void __acp_spi_cs_control_##x(u32 control) \
+{ \
+       __acp_spi_cs_control(control, x); \
+}
+
+DECLARE_PL022_CS_FUN(0);
+DECLARE_PL022_CS_FUN(1);
+DECLARE_PL022_CS_FUN(2);
+DECLARE_PL022_CS_FUN(3);
+DECLARE_PL022_CS_FUN(4);
+DECLARE_PL022_CS_FUN(5);
+DECLARE_PL022_CS_FUN(6);
+DECLARE_PL022_CS_FUN(7);
+
+static void (*acp_cs_control[])(u32) = {
+       __acp_spi_cs_control_0,
+       __acp_spi_cs_control_1,
+       __acp_spi_cs_control_2,
+       __acp_spi_cs_control_3,
+       __acp_spi_cs_control_4,
+       __acp_spi_cs_control_5,
+       __acp_spi_cs_control_6,
+       __acp_spi_cs_control_7,
+};
+
+struct pl022_config_chip eeprom_chip_info = {
+       .iface = SSP_INTERFACE_MOTOROLA_SPI,
+       .hierarchy = SSP_MASTER,
+       .clk_freq = {
+               .cpsdvsr = 0x2,
+               .scr = 0x31,
+       },
+       .com_mode = INTERRUPT_TRANSFER,
+       .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
+       .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
+       .ctrl_len = SSP_BITS_8,
+       .wait_state = SSP_MWIRE_WAIT_ZERO,
+       .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
+};
+
+struct spi_eeprom eeprom_chip = {
+       .flags = EE_ADDR3 | EE_READONLY,
+       .byte_len = 128*1024,
+};
+
+static void register_spi_device(struct pl022 *pl022)
+{
+       struct spi_device *spi;
+       struct device_node *nc;
+       const __be32 *prop;
+       int rc;
+       int len;
+       struct spi_master *master = pl022->master;
+
+       int is_at25;
+
+       /* Save pl022 io base for cs functions */
+       pl022_virtbase = pl022->virtbase;
+       for_each_child_of_node(pl022->dev->dev.of_node, nc) {
+               /* Alloc an spi_device */
+               spi = spi_alloc_device(pl022->master);
+               if (!spi) {
+                       dev_err(&master->dev, "spi_device alloc error for %s\n",
+                               nc->full_name);
+                       spi_dev_put(spi);
+                       continue;
+               }
+               /* Select device driver */
+               is_at25 = 0;
+               if (of_device_is_compatible(nc, "at25")) {
+                       sprintf(spi->modalias, "at25");
+                       is_at25 = 1;
+               } else if (of_modalias_node(nc, spi->modalias,
+                       sizeof(spi->modalias)) < 0) {
+                       dev_err(&master->dev, "cannot find modalias for %s\n",
+                               nc->full_name);
+                       spi_dev_put(spi);
+                       continue;
+               }
+
+               /* Device address */
+               prop = of_get_property(nc, "reg", &len);
+               if (!prop || len < sizeof(*prop)) {
+                       dev_err(&master->dev, "%s has no 'reg' property\n",
+                               nc->full_name);
+                       spi_dev_put(spi);
+                       continue;
+               }
+               spi->chip_select = be32_to_cpup(prop);
+               if (spi->chip_select >= master->num_chipselect) {
+                       dev_err(&master->dev, "%s got a wrong cs %d\n",
+                               nc->full_name, spi->chip_select);
+                       spi_dev_put(spi);
+                       continue;
+               }
+
+               /* Mode (clock phase/polarity/etc.) */
+               if (of_find_property(nc, "spi-cpha", NULL))
+                       spi->mode |= SPI_CPHA;
+               if (of_find_property(nc, "spi-cpol", NULL))
+                       spi->mode |= SPI_CPOL;
+               if (of_find_property(nc, "spi-cs-high", NULL))
+                       spi->mode |= SPI_CS_HIGH;
+
+               /* Device speed */
+               prop = of_get_property(nc, "spi-max-frequency", &len);
+               if (!prop || len < sizeof(*prop)) {
+                       dev_err(&master->dev, "%s has no 'spi-max-frequency' 
property\n",
+                               nc->full_name);
+                       spi_dev_put(spi);
+                       continue;
+               }
+               spi->max_speed_hz = be32_to_cpup(prop);
+
+               /* IRQ */
+               spi->irq = irq_of_parse_and_map(nc, 0);
+
+               /* Store a pointer to the node in the device structure */
+               of_node_get(nc);
+               spi->dev.of_node = nc;
+
+               if (is_at25) {
+                       eeprom_chip_info.cs_control =
+                               acp_cs_control[spi->chip_select],
+                       spi->controller_data = &eeprom_chip_info;
+                       spi->dev.platform_data = &eeprom_chip;
+               }
+
+               /* Register the new device */
+               request_module(spi->modalias);
+               rc = spi_add_device(spi);
+               if (rc) {
+                       dev_err(&master->dev, "spi_device register error %s\n",
+                               nc->full_name);
+                       spi_dev_put(spi);
+               }
+       }
+}
+
+static struct of_device_id pl022_match[];
+
+static int
+pl022_of_probe(struct platform_device *ofdev)
+{
+       struct pl022_ssp_controller *platform_info;
+       int ret = -ENODEV;
+       struct resource r_mem;
+       int irq;
+       struct pl022 *pl022 = NULL;
+       const u32 *prop;
+       int len;
+       struct device_node *of_node = ofdev->dev.of_node;
+       const struct of_device_id *id = of_match_node(pl022_match, of_node);
+
+       platform_info = kmalloc(sizeof(struct pl022_ssp_controller),
+               GFP_KERNEL);
+       if (!platform_info)
+               return -ENOMEM;
+
+       prop = of_get_property(of_node, "cell-index", &len);
+       if (!prop || len < sizeof(*prop)) {
+               dev_warn(&ofdev->dev, "no 'cell-index' property\n");
+               goto err_data;
+       }
+       platform_info->bus_id = *prop;
+       /* number of slave select bits is required */
+       prop = of_get_property(of_node, "num-ss-bits", &len);
+       if (!prop || len < sizeof(*prop)) {
+               dev_warn(&ofdev->dev, "no 'num-ss-bits' property\n");
+               goto err_data;
+       }
+       platform_info->num_chipselect = *prop;
+       /* number of slave select bits is required */
+       prop = of_get_property(of_node, "enalbe-dma", &len);
+       if (!prop || len < sizeof(*prop))
+               platform_info->enable_dma = 0;
+       platform_info->enable_dma = *prop;
+
+       ofdev->dev.platform_data = platform_info;
+
+       ret = of_address_to_resource(of_node, 0, &r_mem);
+       if (ret) {
+               dev_warn(&ofdev->dev, "invalid address\n");
+               goto err_data;
+       }
+
+       irq = of_irq_to_resource(of_node, 0, NULL);
+
+       ret = pl022_probe(&ofdev->dev, id->data, &r_mem, irq, &pl022);
+
+       if (ret < 0)
+               goto err_data;
+
+       pl022->dev = ofdev;
+       register_spi_device(pl022);
+       return 0;
+err_data:
+       kfree(platform_info);
+       return ret;
+}
+
+static int
+pl022_of_remove(struct platform_device *ofdev)
+{
+       struct resource r_mem;
+       int irq;
+       int ret;
+       struct device_node *of_node = ofdev->dev.of_node;
+
+       of_address_to_resource(of_node, 0, &r_mem);
+
+       irq = of_irq_to_resource(of_node, 0, NULL);
+
+       ret = pl022_remove(&ofdev->dev, &r_mem, irq);
+       if (ret)
+               return ret;
+       kfree(ofdev->dev.platform_data);
+       return 0;
+}
+
+static struct of_device_id pl022_match[] = {
+       {
+               .compatible = "arm, acp-ssp",
+               .data = (void *)&vendor_arm,
+       },
+       {
+               .compatible = "acp-ssp, ",
+               .data = (void *)&vendor_arm,
+       },
+       { /* end of list */ },
+};
+
+static struct platform_driver pl022_driver = {
+       .driver = {
+               .name   = "ssp-pl022",
+               .pm     = &pl022_dev_pm_ops,
+               .of_match_table = pl022_match,
+       },
+       .probe = pl022_of_probe,
+       .remove = pl022_of_remove,
+};
+
+module_platform_driver(pl022_driver);
+
+MODULE_AUTHOR("Linus Walleij <linus.wall...@stericsson.com>");
+MODULE_DESCRIPTION("PL022 SSP Controller Driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c
index ee513a8..8dd1b24 100644
--- a/drivers/spi/spi-pl022.c
+++ b/drivers/spi/spi-pl022.c
@@ -50,7 +50,7 @@
  * val shifted sb steps to the left.
  */
 #define SSP_WRITE_BITS(reg, val, mask, sb) \
- ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
+       ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
 
 /*
  * This macro is also used to define some default values.
@@ -58,7 +58,7 @@
  * the result with mask.
  */
 #define GEN_MASK_BITS(val, mask, sb) \
- (((val)<<(sb)) & (mask))
+       (((val)<<(sb)) & (mask))
 
 #define DRIVE_TX               0
 #define DO_NOT_DRIVE_TX                1
@@ -377,6 +377,11 @@ struct pl022 {
        resource_size_t                 phybase;
        void __iomem                    *virtbase;
        struct clk                      *clk;
+       /* Two optional pin states - default & sleep */
+       struct pinctrl                  *pinctrl;
+       struct pinctrl_state            *pins_default;
+       struct pinctrl_state            *pins_idle;
+       struct pinctrl_state            *pins_sleep;
        struct spi_master               *master;
        struct pl022_ssp_controller     *master_info;
        /* Message per-transfer pump */
@@ -433,7 +438,7 @@ struct chip_data {
        bool enable_dma;
        enum ssp_reading read;
        enum ssp_writing write;
-       void (*cs_control) (u32 command);
+       void (*cs_control)(u32 command);
        int xfer_type;
 };
 
@@ -489,6 +494,7 @@ static void pl022_cs_control(struct pl022 *pl022, u32 
command)
 static void giveback(struct pl022 *pl022)
 {
        struct spi_transfer *last_transfer;
+
        pl022->next_msg_cs_active = false;
 
        last_transfer = list_last_entry(&pl022->cur_msg->transfers,
@@ -1106,7 +1112,7 @@ err_rxdesc:
                     pl022->sgt_tx.nents, DMA_TO_DEVICE);
 err_tx_sgmap:
        dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
-                    pl022->sgt_rx.nents, DMA_FROM_DEVICE);
+                    pl022->sgt_tx.nents, DMA_FROM_DEVICE);
 err_rx_sgmap:
        sg_free_table(&pl022->sgt_tx);
 err_alloc_tx_sg:
@@ -1191,7 +1197,7 @@ err_no_txchan:
 err_no_rxchan:
        return -ENODEV;
 }
-               
+
 static void terminate_dma(struct pl022 *pl022)
 {
        struct dma_chan *rxchan = pl022->dma_rx_channel;
@@ -1554,7 +1560,6 @@ out:
                message->status = -EIO;
 
        giveback(pl022);
-       return;
 }
 
 static int pl022_transfer_one_message(struct spi_master *master,
@@ -1584,6 +1589,18 @@ static int pl022_transfer_one_message(struct spi_master 
*master,
        return 0;
 }
 
+static int pl022_prepare_transfer_hardware(struct spi_master *master)
+{
+       struct pl022 *pl022 = spi_master_get_devdata(master);
+
+       /*
+        * Just make sure we have all we need to run the transfer by syncing
+        * with the runtime PM framework.
+        */
+       pm_runtime_get_sync(&pl022->adev->dev);
+       return 0;
+}
+
 static int pl022_unprepare_transfer_hardware(struct spi_master *master)
 {
        struct pl022 *pl022 = spi_master_get_devdata(master);
@@ -1592,6 +1609,13 @@ static int pl022_unprepare_transfer_hardware(struct 
spi_master *master)
        writew((readw(SSP_CR1(pl022->virtbase)) &
                (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
 
+       if (pl022->master_info->autosuspend_delay > 0) {
+               pm_runtime_mark_last_busy(&pl022->adev->dev);
+               pm_runtime_put_autosuspend(&pl022->adev->dev);
+       } else {
+               pm_runtime_put(&pl022->adev->dev);
+       }
+
        return 0;
 }
 
@@ -1776,7 +1800,7 @@ static int calculate_effective_freq(struct pl022 *pl022, 
int freq, struct
                scr = SCR_MIN;
        }
 
-       WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz 
rate \n",
+       WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz 
rate\n",
                        freq);
 
        clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
@@ -2081,7 +2105,6 @@ pl022_platform_data_dt_get(struct device *dev)
                return NULL;
 
        pd->bus_id = -1;
-       pd->enable_dma = 1;
        of_property_read_u32(np, "num-cs", &tmp);
        pd->num_chipselect = tmp;
        of_property_read_u32(np, "pl022,autosuspend-delay",
@@ -2094,8 +2117,7 @@ pl022_platform_data_dt_get(struct device *dev)
 static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
 {
        struct device *dev = &adev->dev;
-       struct pl022_ssp_controller *platform_info =
-                       dev_get_platdata(&adev->dev);
+       struct pl022_ssp_controller *platform_info = adev->dev.platform_data;
        struct spi_master *master;
        struct pl022 *pl022 = NULL;     /*Data for this driver */
        struct device_node *np = adev->dev.of_node;
@@ -2132,11 +2154,34 @@ static int pl022_probe(struct amba_device *adev, const 
struct amba_id *id)
        pl022->vendor = id->data;
        pl022->chipselects = devm_kzalloc(dev, num_cs * sizeof(int),
                                          GFP_KERNEL);
-       if (!pl022->chipselects) {
-               status = -ENOMEM;
-               goto err_no_mem;
+
+       pl022->pinctrl = devm_pinctrl_get(dev);
+       if (IS_ERR(pl022->pinctrl)) {
+               status = PTR_ERR(pl022->pinctrl);
+               goto err_no_pinctrl;
        }
 
+       pl022->pins_default = pinctrl_lookup_state(pl022->pinctrl,
+                                                PINCTRL_STATE_DEFAULT);
+       /* enable pins to be muxed in and configured */
+       if (!IS_ERR(pl022->pins_default)) {
+               status = pinctrl_select_state(pl022->pinctrl,
+                               pl022->pins_default);
+               if (status)
+                       dev_err(dev, "could not set default pins\n");
+       } else
+               dev_err(dev, "could not get default pinstate\n");
+
+       pl022->pins_idle = pinctrl_lookup_state(pl022->pinctrl,
+                                             PINCTRL_STATE_IDLE);
+       if (IS_ERR(pl022->pins_idle))
+               dev_dbg(dev, "could not get idle pinstate\n");
+
+       pl022->pins_sleep = pinctrl_lookup_state(pl022->pinctrl,
+                                              PINCTRL_STATE_SLEEP);
+       if (IS_ERR(pl022->pins_sleep))
+               dev_dbg(dev, "could not get sleep pinstate\n");
+
        /*
         * Bus Number Which has been Assigned to this SSP controller
         * on this board
@@ -2145,7 +2190,7 @@ static int pl022_probe(struct amba_device *adev, const 
struct amba_id *id)
        master->num_chipselect = num_cs;
        master->cleanup = pl022_cleanup;
        master->setup = pl022_setup;
-       master->auto_runtime_pm = true;
+       master->prepare_transfer_hardware = pl022_prepare_transfer_hardware;
        master->transfer_one_message = pl022_transfer_one_message;
        master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
        master->rt = platform_info->rt;
@@ -2202,8 +2247,8 @@ static int pl022_probe(struct amba_device *adev, const 
struct amba_id *id)
                status = -ENOMEM;
                goto err_no_ioremap;
        }
-       dev_info(&adev->dev, "mapped registers from %pa to %p\n",
-               &adev->res.start, pl022->virtbase);
+       pr_info("pl022: mapped registers from 0x%08lx to %p\n",
+               (unsigned long)adev->res.start, pl022->virtbase);
 
        pl022->clk = devm_clk_get(&adev->dev, NULL);
        if (IS_ERR(pl022->clk)) {
@@ -2248,7 +2293,7 @@ static int pl022_probe(struct amba_device *adev, const 
struct amba_id *id)
 
        /* Register with the SPI framework */
        amba_set_drvdata(adev, pl022);
-       status = devm_spi_register_master(&adev->dev, master);
+       status = spi_register_master(master);
        if (status != 0) {
                dev_err(&adev->dev,
                        "probe - problem registering spi master\n");
@@ -2280,7 +2325,7 @@ static int pl022_probe(struct amba_device *adev, const 
struct amba_id *id)
        amba_release_regions(adev);
  err_no_ioregion:
  err_no_gpio:
- err_no_mem:
+ err_no_pinctrl:
        spi_master_put(master);
        return status;
 }
@@ -2306,10 +2351,63 @@ pl022_remove(struct amba_device *adev)
        clk_disable_unprepare(pl022->clk);
        amba_release_regions(adev);
        tasklet_disable(&pl022->pump_transfers);
+       spi_unregister_master(pl022->master);
+       amba_set_drvdata(adev, NULL);
        return 0;
 }
 
-#ifdef CONFIG_PM_SLEEP
+#if defined(CONFIG_SUSPEND) || defined(CONFIG_PM_RUNTIME)
+/*
+ * These two functions are used from both suspend/resume and
+ * the runtime counterparts to handle external resources like
+ * clocks, pins and regulators when going to sleep.
+ */
+static void pl022_suspend_resources(struct pl022 *pl022, bool runtime)
+{
+       int ret;
+       struct pinctrl_state *pins_state;
+
+       clk_disable(pl022->clk);
+
+       pins_state = runtime ? pl022->pins_idle : pl022->pins_sleep;
+       /* Optionally let pins go into sleep states */
+       if (!IS_ERR(pins_state)) {
+               ret = pinctrl_select_state(pl022->pinctrl, pins_state);
+               if (ret)
+                       dev_err(&pl022->adev->dev, "could not set %s pins\n",
+                               runtime ? "idle" : "sleep");
+       }
+}
+
+static void pl022_resume_resources(struct pl022 *pl022, bool runtime)
+{
+       int ret;
+
+       /* Optionaly enable pins to be muxed in and configured */
+       /* First go to the default state */
+       if (!IS_ERR(pl022->pins_default)) {
+               ret = pinctrl_select_state(pl022->pinctrl, pl022->pins_default);
+               if (ret)
+                       dev_err(&pl022->adev->dev,
+                               "could not set default pins\n");
+       }
+
+       if (!runtime) {
+               /* Then let's idle the pins until the next transfer happens */
+               if (!IS_ERR(pl022->pins_idle)) {
+                       ret = pinctrl_select_state(pl022->pinctrl,
+                                       pl022->pins_idle);
+               if (ret)
+                       dev_err(&pl022->adev->dev,
+                               "could not set idle pins\n");
+               }
+       }
+
+       clk_enable(pl022->clk);
+}
+#endif
+
+#ifdef CONFIG_SUSPEND
 static int pl022_suspend(struct device *dev)
 {
        struct pl022 *pl022 = dev_get_drvdata(dev);
-- 
1.7.9.5

-- 
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