From: Feng Tang
dw_spi driver in upstream only supports PIO mode, and this patch
will support it to cowork with the Designware DMA controller used
on Intel Moorestown platform
It has been tested with a Option GTM501L 3G modem, to use DMA mode,
DMA controller 2 of Moorestown has to be enabled
Signed-off-by: Feng Tang
[Typo fix and renames to match intel_mid_dma renaming]
Signed-off-by: Vinod Koul
[Clean up]
Signed-off-by: Feng Tang
[Fix timing delay, add cpu_relax]
Signed-off-by: Arjan van de Ven
Signed-off-by: Alan Cox
---
drivers/spi/Kconfig|4 +
drivers/spi/Makefile |3 -
drivers/spi/dw_spi.c | 48 +
drivers/spi/dw_spi_mid.c | 246
drivers/spi/dw_spi_pci.c | 14 ++-
include/linux/spi/dw_spi.h | 15 +++
6 files changed, 305 insertions(+), 25 deletions(-)
create mode 100644 drivers/spi/dw_spi_mid.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 82e45cf..6e6a638 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -404,6 +404,10 @@ config SPI_DW_PCI
tristate "PCI interface driver for DW SPI core"
depends on SPI_DESIGNWARE && PCI
+config SPI_DW_MID_DMA
+ bool "DMA support for DW SPI controller on Intel Moorestown platform"
+ depends on SPI_DW_PCI && INTEL_MID_DMAC
+
config SPI_DW_MMIO
tristate "Memory-mapped io interface driver for DW SPI core"
depends on SPI_DESIGNWARE && HAVE_CLK
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index b427c2e..4949370 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -17,7 +17,8 @@ obj-$(CONFIG_SPI_BUTTERFLY) += spi_butterfly.o
obj-$(CONFIG_SPI_COLDFIRE_QSPI)+= coldfire_qspi.o
obj-$(CONFIG_SPI_DAVINCI) += davinci_spi.o
obj-$(CONFIG_SPI_DESIGNWARE) += dw_spi.o
-obj-$(CONFIG_SPI_DW_PCI) += dw_spi_pci.o
+obj-$(CONFIG_SPI_DW_PCI) += dw_spi_midpci.o
+dw_spi_midpci-objs := dw_spi_pci.o dw_spi_mid.o
obj-$(CONFIG_SPI_DW_MMIO) += dw_spi_mmio.o
obj-$(CONFIG_SPI_EP93XX) += ep93xx_spi.o
obj-$(CONFIG_SPI_GPIO) += spi_gpio.o
diff --git a/drivers/spi/dw_spi.c b/drivers/spi/dw_spi.c
index 9043931..69cc223 100644
--- a/drivers/spi/dw_spi.c
+++ b/drivers/spi/dw_spi.c
@@ -164,20 +164,23 @@ static inline void mrst_spi_debugfs_remove(struct dw_spi
*dws)
static void wait_till_not_busy(struct dw_spi *dws)
{
- unsigned long end = jiffies + 1 + usecs_to_jiffies(1000);
+ unsigned long end = jiffies + 1 + usecs_to_jiffies(5000);
while (time_before(jiffies, end)) {
if (!(dw_readw(dws, sr) & SR_BUSY))
return;
+ cpu_relax();
}
dev_err(&dws->master->dev,
- "DW SPI: Status keeps busy for 1000us after a read/write!\n");
+ "DW SPI: Status keeps busy for 5000us after a read/write!\n");
}
static void flush(struct dw_spi *dws)
{
- while (dw_readw(dws, sr) & SR_RF_NOT_EMPT)
+ while (dw_readw(dws, sr) & SR_RF_NOT_EMPT) {
dw_readw(dws, dr);
+ cpu_relax();
+ }
wait_till_not_busy(dws);
}
@@ -285,8 +288,10 @@ static void *next_transfer(struct dw_spi *dws)
*/
static int map_dma_buffers(struct dw_spi *dws)
{
- if (!dws->cur_msg->is_dma_mapped || !dws->dma_inited
- || !dws->cur_chip->enable_dma)
+ if (!dws->cur_msg->is_dma_mapped
+ || !dws->dma_inited
+ || !dws->cur_chip->enable_dma
+ || !dws->dma_ops)
return 0;
if (dws->cur_transfer->tx_dma)
@@ -338,7 +343,7 @@ static void int_error_stop(struct dw_spi *dws, const char
*msg)
tasklet_schedule(&dws->pump_transfers);
}
-static void transfer_complete(struct dw_spi *dws)
+void dw_spi_xfer_done(struct dw_spi *dws)
{
/* Update total byte transfered return count actual bytes read */
dws->cur_msg->actual_length += dws->len;
@@ -353,6 +358,7 @@ static void transfer_complete(struct dw_spi *dws)
} else
tasklet_schedule(&dws->pump_transfers);
}
+EXPORT_SYMBOL_GPL(dw_spi_xfer_done);
static irqreturn_t interrupt_transfer(struct dw_spi *dws)
{
@@ -384,7 +390,7 @@ static irqreturn_t interrupt_transfer(struct dw_spi *dws)
if (dws->tx_end > dws->tx)
spi_umask_intr(dws, SPI_INT_TXEI);
else
- transfer_complete(dws);
+ dw_spi_xfer_done(dws);
}
return IRQ_HANDLED;
@@ -414,11 +420,7 @@ static void poll_transfer(struct dw_spi *dws)
while (dws->write(dws))
dws->read(dws);
- transfer_complete(dws);
-}
-
-static void dma_transfer(struct dw_spi *dws, int cs_change)
-{
+ dw_spi_xfer_done(dws);
}
static void pump_transfers(unsigned long data)
@@ -600,7 +602,7 @@ stat
