Add support for Qualcomm I2C QUP driver which is inspired from
corresponding driver in Linux: drivers/i2c/busses/i2c-qup.c.

Currently this driver only support FIFO polling mode which is sufficient
to support devices like eeprom, rtc etc.

Co-developed-by: Mike Worsfold <mworsf...@impinj.com>
Signed-off-by: Mike Worsfold <mworsf...@impinj.com>
Signed-off-by: Sumit Garg <sumit.g...@linaro.org>
---
 drivers/i2c/Kconfig   |   6 +
 drivers/i2c/Makefile  |   1 +
 drivers/i2c/qup_i2c.c | 592 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 599 insertions(+)
 create mode 100644 drivers/i2c/qup_i2c.c

diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index 76e19918aa..2a1d36f91a 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -635,6 +635,12 @@ config SYS_I2C_TEGRA
        help
          Support for NVIDIA I2C controller available in Tegra SoCs.
 
+config SYS_I2C_QUP
+       bool "Qualcomm I2C controller"
+       depends on ARCH_SNAPDRAGON
+       help
+         Support for Qualcomm I2C controller.
+
 config SYS_I2C_UNIPHIER
        bool "UniPhier I2C driver"
        depends on ARCH_UNIPHIER && DM_I2C
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index 920aafb91c..f6aa39dd7a 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -50,6 +50,7 @@ obj-$(CONFIG_SYS_I2C_SUN6I_P2WI) += sun6i_p2wi.o
 obj-$(CONFIG_SYS_I2C_SUN8I_RSB) += sun8i_rsb.o
 obj-$(CONFIG_SYS_I2C_SYNQUACER) += synquacer_i2c.o
 obj-$(CONFIG_SYS_I2C_TEGRA) += tegra_i2c.o
+obj-$(CONFIG_SYS_I2C_QUP) += qup_i2c.o
 obj-$(CONFIG_SYS_I2C_UNIPHIER) += i2c-uniphier.o
 obj-$(CONFIG_SYS_I2C_UNIPHIER_F) += i2c-uniphier-f.o
 obj-$(CONFIG_SYS_I2C_VERSATILE) += i2c-versatile.o
diff --git a/drivers/i2c/qup_i2c.c b/drivers/i2c/qup_i2c.c
new file mode 100644
index 0000000000..6787fc75fc
--- /dev/null
+++ b/drivers/i2c/qup_i2c.c
@@ -0,0 +1,592 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2009-2013, 2016-2018, The Linux Foundation. All rights 
reserved.
+ * Copyright (c) 2014, Sony Mobile Communications AB.
+ * Copyright (c) 2022-2023, Sumit Garg <sumit.g...@linaro.org>
+ *
+ * Inspired by corresponding driver in Linux: drivers/i2c/busses/i2c-qup.c
+ */
+
+#include <init.h>
+#include <env.h>
+#include <common.h>
+#include <log.h>
+#include <dm/device_compat.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/compat.h>
+#include <linux/bitops.h>
+#include <asm/io.h>
+#include <i2c.h>
+#include <watchdog.h>
+#include <fdtdec.h>
+#include <clk.h>
+#include <reset.h>
+#include <asm/arch/gpio.h>
+#include <cpu_func.h>
+#include <asm/system.h>
+#include <asm/gpio.h>
+#include <dm.h>
+#include <dm/pinctrl.h>
+
+/* QUP Registers */
+#define QUP_CONFIG                             0x000
+#define QUP_STATE                              0x004
+#define QUP_IO_MODE                            0x008
+#define QUP_SW_RESET                           0x00c
+#define QUP_OPERATIONAL                                0x018
+#define QUP_ERROR_FLAGS                                0x01c
+#define QUP_ERROR_FLAGS_EN                     0x020
+#define QUP_TEST_CTRL                          0x024 /* NOT USED */
+#define QUP_OPERATIONAL_MASK                   0x028
+#define QUP_HW_VERSION                         0x030
+#define QUP_MX_OUTPUT_CNT                      0x100
+#define QUP_OUT_DEBUG                          0x108 /* NOT USED */
+#define QUP_OUT_FIFO_CNT                       0x10C /* NOT USED */
+#define QUP_OUT_FIFO_BASE                      0x110
+#define QUP_MX_WRITE_CNT                       0x150
+#define QUP_MX_INPUT_CNT                       0x200
+#define QUP_MX_READ_CNT                                0x208
+#define QUP_IN_READ_CUR                                0x20C /* NOT USED */
+#define QUP_IN_DEBUG                           0x210 /* NOT USED */
+#define QUP_IN_FIFO_CNT                                0x214 /* NOT USED */
+#define QUP_IN_FIFO_BASE                       0x218
+#define QUP_I2C_CLK_CTL                                0x400
+#define QUP_I2C_STATUS                         0x404
+#define QUP_I2C_MASTER_GEN                     0x408
+#define QUP_I2C_MASTER_BUS_CLR                 0x40C /* NOT USED */
+
+/* QUP States and reset values */
+#define QUP_RESET_STATE                                0
+#define QUP_RUN_STATE                          1
+#define QUP_PAUSE_STATE                                3
+#define QUP_STATE_MASK                         3
+
+#define QUP_STATE_VALID                                BIT(2)
+#define QUP_I2C_MAST_GEN                       BIT(4)
+#define QUP_I2C_FLUSH                          BIT(6)
+
+#define QUP_OPERATIONAL_RESET                  0x000ff0
+#define QUP_I2C_STATUS_RESET                   0xfffffc
+
+/* QUP OPERATIONAL FLAGS */
+#define QUP_I2C_NACK_FLAG                      BIT(3)
+#define QUP_OUT_NOT_EMPTY                      BIT(4)
+#define QUP_IN_NOT_EMPTY                       BIT(5)
+#define QUP_OUT_FULL                           BIT(6)
+#define QUP_OUT_SVC_FLAG                       BIT(8)
+#define QUP_IN_SVC_FLAG                                BIT(9)
+#define QUP_MX_OUTPUT_DONE                     BIT(10)
+#define QUP_MX_INPUT_DONE                      BIT(11)
+#define OUT_BLOCK_WRITE_REQ                    BIT(12)
+#define IN_BLOCK_READ_REQ                      BIT(13)
+
+/* I2C mini core related values */
+#define QUP_NO_OUTPUT                          BIT(6)
+#define QUP_NO_INPUT                           BIT(7)
+#define QUP_CLOCK_AUTO_GATE                    BIT(13)
+#define I2C_MINI_CORE                          (2 << 8)
+#define I2C_N_VAL                              15
+#define I2C_N_VAL_V2                           7
+
+/* Most significant word offset in FIFO port */
+#define QUP_MSW_SHIFT                          (I2C_N_VAL + 1)
+
+/* Packing/Unpacking words in FIFOs, and IO modes */
+#define QUP_OUTPUT_BLK_MODE                    BIT(10)
+#define QUP_OUTPUT_BAM_MODE                    (BIT(10) | BIT(11))
+#define QUP_INPUT_BLK_MODE                     BIT(12)
+#define QUP_INPUT_BAM_MODE                     (BIT(12) | BIT(13))
+#define QUP_BAM_MODE                           (QUP_OUTPUT_BAM_MODE | 
QUP_INPUT_BAM_MODE)
+#define QUP_BLK_MODE                           (QUP_OUTPUT_BLK_MODE | 
QUP_INPUT_BLK_MODE)
+#define QUP_UNPACK_EN                          BIT(14)
+#define QUP_PACK_EN                            BIT(15)
+
+#define QUP_REPACK_EN                          (QUP_UNPACK_EN | QUP_PACK_EN)
+#define QUP_V2_TAGS_EN                         1
+
+#define QUP_OUTPUT_BLOCK_SIZE(x)               (((x) >> 0) & 0x03)
+#define QUP_OUTPUT_FIFO_SIZE(x)                        (((x) >> 2) & 0x07)
+#define QUP_INPUT_BLOCK_SIZE(x)                        (((x) >> 5) & 0x03)
+#define QUP_INPUT_FIFO_SIZE(x)                 (((x) >> 7) & 0x07)
+
+/* QUP v2 tags */
+#define QUP_TAG_V2_START                       0x81
+#define QUP_TAG_V2_DATAWR                      0x82
+#define QUP_TAG_V2_DATAWR_STOP                 0x83
+#define QUP_TAG_V2_DATARD                      0x85
+#define QUP_TAG_V2_DATARD_NACK                 0x86
+#define QUP_TAG_V2_DATARD_STOP                 0x87
+
+/* Status, Error flags */
+#define I2C_STATUS_WR_BUFFER_FULL              BIT(0)
+#define I2C_STATUS_BUS_ERROR                   BIT(2)
+#define I2C_STATUS_PACKET_NACKED               BIT(3)
+#define I2C_STATUS_ARB_LOST                    BIT(4)
+#define I2C_STATUS_INVALID_WRITE               BIT(5)
+#define I2C_STATUS_FAILED                      BIT(6)
+#define I2C_STATUS_BUS_ACTIVE                  BIT(8)
+#define I2C_STATUS_BUS_MASTER                  BIT(9)
+#define I2C_STATUS_INVALID_TAG                 BIT(23)
+#define I2C_STATUS_INVALID_READ_ADDR           BIT(24)
+#define I2C_STATUS_INVALID_READ_SEQ            BIT(25)
+#define I2C_STATUS_I2C_SDA                     BIT(26)
+#define I2C_STATUS_I2C_SCL                     BIT(27)
+#define I2C_STATUS_ERROR_MASK                  0x38000fc
+#define QUP_STATUS_ERROR_FLAGS                 0x7c
+
+#define QUP_I2C_MX_CONFIG_DURING_RUN           BIT(31)
+
+/* Minimum transfer timeout for i2c transfers in micro seconds */
+#define TOUT_CNT                               2 * 1000 * 1000
+
+/* Default values. Use these if FW query fails */
+#define DEFAULT_CLK_FREQ                       I2C_SPEED_STANDARD_RATE
+#define DEFAULT_SRC_CLK                                19200000
+
+/*
+ * Max tags length (start, stop and maximum 2 bytes address) for each QUP
+ * data transfer
+ */
+#define QUP_MAX_TAGS_LEN                       4
+/* Max data length for each DATARD tags */
+#define RECV_MAX_DATA_LEN                      254
+/* TAG length for DATA READ in RX FIFO */
+#define READ_RX_TAGS_LEN                       2
+
+struct qup_i2c_priv {
+       phys_addr_t base;
+       struct clk core;
+       struct clk iface;
+       u32 in_fifo_sz;
+       u32 out_fifo_sz;
+       u32 clk_ctl;
+       u32 config_run;
+};
+
+static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg)
+{
+       return (msg->addr << 1) | (msg->flags & I2C_M_RD ? 1 : 0);
+}
+
+static int qup_i2c_poll_state_mask(struct qup_i2c_priv *qup,
+                                  u32 req_state, u32 req_mask)
+{
+       int retries = 1;
+       u32 state;
+
+       /*
+        * State transition takes 3 AHB clocks cycles + 3 I2C master clock
+        * cycles. So retry once after a 1uS delay.
+        */
+       do {
+               state = readl(qup->base + QUP_STATE);
+
+               if (state & QUP_STATE_VALID &&
+                   (state & req_mask) == req_state)
+                       return 0;
+
+               udelay(1);
+       } while (retries--);
+
+       return -ETIMEDOUT;
+}
+
+static int qup_i2c_poll_state(struct qup_i2c_priv *qup, u32 req_state)
+{
+       return qup_i2c_poll_state_mask(qup, req_state, QUP_STATE_MASK);
+}
+
+static int qup_i2c_poll_state_valid(struct qup_i2c_priv *qup)
+{
+       return qup_i2c_poll_state_mask(qup, 0, 0);
+}
+
+static int qup_i2c_poll_state_i2c_master(struct qup_i2c_priv *qup)
+{
+       return qup_i2c_poll_state_mask(qup, QUP_I2C_MAST_GEN, QUP_I2C_MAST_GEN);
+}
+
+static int qup_i2c_change_state(struct qup_i2c_priv *qup, u32 state)
+{
+       if (qup_i2c_poll_state_valid(qup) != 0)
+               return -EIO;
+
+       writel(state, qup->base + QUP_STATE);
+
+       if (qup_i2c_poll_state(qup, state) != 0)
+               return -EIO;
+       return 0;
+}
+
+/*
+ * Function to check wheather Input or Output FIFO
+ * has data to be serviced
+ */
+static int qup_i2c_check_fifo_status(struct qup_i2c_priv *qup, u32 reg_addr,
+                                    u32 flags)
+{
+       unsigned long count = TOUT_CNT;
+       u32 val, status_flag;
+       int ret = 0;
+
+       do {
+               val = readl(qup->base + reg_addr);
+               status_flag = val & flags;
+
+               if (!count) {
+                       printf("%s, timeout\n", __func__);
+                       ret = -ETIMEDOUT;
+                       break;
+               }
+
+               count--;
+               udelay(1);
+       } while (!status_flag);
+
+       return ret;
+}
+
+/*
+ * Function to configure Input and Output enable/disable
+ */
+static void qup_i2c_enable_io_config(struct qup_i2c_priv *qup, u32 write_cnt,
+                                    u32 read_cnt)
+{
+       u32 qup_config = I2C_MINI_CORE | I2C_N_VAL_V2;
+
+       writel(qup->config_run | write_cnt, qup->base + QUP_MX_WRITE_CNT);
+
+       if (read_cnt)
+               writel(qup->config_run | read_cnt, qup->base + QUP_MX_READ_CNT);
+       else
+               qup_config |= QUP_NO_INPUT;
+
+       writel(qup_config, qup->base + QUP_CONFIG);
+}
+
+static unsigned int qup_i2c_read_word(struct qup_i2c_priv *qup)
+{
+       return readl(qup->base + QUP_IN_FIFO_BASE);
+}
+
+static void qup_i2c_write_word(struct qup_i2c_priv *qup, u32 word)
+{
+       writel(word, qup->base + QUP_OUT_FIFO_BASE);
+}
+
+static int qup_i2c_blsp_read(struct qup_i2c_priv *qup, unsigned int addr,
+                            bool last, u8 *buffer, unsigned int bytes)
+{
+       unsigned int i, j, word;
+       int ret = 0;
+
+       /* FIFO mode size limitation, for larger size implement block mode */
+       if (bytes > (qup->in_fifo_sz - READ_RX_TAGS_LEN))
+               return -EINVAL;
+
+       qup_i2c_enable_io_config(qup, QUP_MAX_TAGS_LEN,
+                                bytes + READ_RX_TAGS_LEN);
+
+       if (last)
+               qup_i2c_write_word(qup, QUP_TAG_V2_START | addr << 8 |
+                                       QUP_TAG_V2_DATARD_STOP << 16 |
+                                       bytes << 24);
+       else
+               qup_i2c_write_word(qup, QUP_TAG_V2_START | addr << 8 |
+                                       QUP_TAG_V2_DATARD << 16 | bytes << 24);
+
+       ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+       if (ret)
+               return ret;
+
+       ret = qup_i2c_check_fifo_status(qup, QUP_OPERATIONAL, QUP_OUT_SVC_FLAG);
+       if (ret)
+               return ret;
+       writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL);
+
+       ret = qup_i2c_check_fifo_status(qup, QUP_OPERATIONAL, QUP_IN_SVC_FLAG);
+       if (ret)
+               return ret;
+       writel(QUP_IN_SVC_FLAG, qup->base + QUP_OPERATIONAL);
+
+       word = qup_i2c_read_word(qup);
+       *(buffer++) = (word >> (8 * READ_RX_TAGS_LEN)) & 0xff;
+       if (bytes > 1)
+               *(buffer++) = (word >> (8 * (READ_RX_TAGS_LEN + 1))) & 0xff;
+
+       for (i = 2; i < bytes; i += 4) {
+               word = qup_i2c_read_word(qup);
+
+               for (j = 0; j < 4; j++) {
+                       if ((i + j) == bytes)
+                               break;
+                       *buffer = (word >> (j * 8)) & 0xff;
+                       buffer++;
+               }
+       }
+
+       ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
+       return ret;
+}
+
+static int qup_i2c_blsp_write(struct qup_i2c_priv *qup, unsigned int addr,
+                             bool first, bool last, const u8 *buffer,
+                             unsigned int bytes)
+{
+       unsigned int i;
+       u32 word = 0;
+       int ret = 0;
+
+       /* FIFO mode size limitation, for larger size implement block mode */
+       if (bytes > (qup->out_fifo_sz - QUP_MAX_TAGS_LEN))
+               return -EINVAL;
+
+       qup_i2c_enable_io_config(qup, bytes + QUP_MAX_TAGS_LEN, 0);
+
+       if (first) {
+               ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+               if (ret)
+                       return ret;
+
+               writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
+
+               ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
+               if (ret)
+                       return ret;
+       }
+
+       if (last)
+               qup_i2c_write_word(qup, QUP_TAG_V2_START | addr << 8 |
+                                       QUP_TAG_V2_DATAWR_STOP << 16 |
+                                       bytes << 24);
+       else
+               qup_i2c_write_word(qup, QUP_TAG_V2_START | addr << 8 |
+                                       QUP_TAG_V2_DATAWR << 16 | bytes << 24);
+
+       for (i = 0; i < bytes; i++) {
+               /* Write the byte of data */
+               word |= *buffer << ((i % 4) * 8);
+               if ((i % 4) == 3) {
+                       qup_i2c_write_word(qup, word);
+                       word = 0;
+               }
+               buffer++;
+       }
+
+       if ((i % 4) != 0)
+               qup_i2c_write_word(qup, word);
+
+       ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
+       if (ret)
+               return ret;
+
+       ret = qup_i2c_check_fifo_status(qup, QUP_OPERATIONAL, QUP_OUT_SVC_FLAG);
+       if (ret)
+               return ret;
+       writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL);
+
+       ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
+       return ret;
+}
+
+static void qup_i2c_conf_mode_v2(struct qup_i2c_priv *qup)
+{
+       u32 io_mode = QUP_REPACK_EN;
+
+       writel(0, qup->base + QUP_MX_OUTPUT_CNT);
+       writel(0, qup->base + QUP_MX_INPUT_CNT);
+
+       writel(io_mode, qup->base + QUP_IO_MODE);
+}
+
+static int qup_i2c_xfer_v2(struct udevice *bus, struct i2c_msg msgs[], int num)
+{
+       struct qup_i2c_priv *qup = dev_get_priv(bus);
+       int ret, idx = 0;
+       u32 i2c_addr;
+
+       writel(1, qup->base + QUP_SW_RESET);
+       ret = qup_i2c_poll_state(qup, QUP_RESET_STATE);
+       if (ret)
+               goto out;
+
+       /* Configure QUP as I2C mini core */
+       writel(I2C_MINI_CORE | I2C_N_VAL_V2 | QUP_NO_INPUT,
+              qup->base + QUP_CONFIG);
+       writel(QUP_V2_TAGS_EN, qup->base + QUP_I2C_MASTER_GEN);
+
+       if (qup_i2c_poll_state_i2c_master(qup)) {
+               ret = -EIO;
+               goto out;
+       }
+
+       qup_i2c_conf_mode_v2(qup);
+
+       for (idx = 0; idx < num; idx++) {
+               struct i2c_msg *m = &msgs[idx];
+
+               qup->config_run = !idx ? 0 : QUP_I2C_MX_CONFIG_DURING_RUN;
+               i2c_addr = i2c_8bit_addr_from_msg(m);
+
+               if (m->flags & I2C_M_RD)
+                       ret = qup_i2c_blsp_read(qup, i2c_addr, idx == (num - 1),
+                                               m->buf, m->len);
+               else
+                       ret = qup_i2c_blsp_write(qup, i2c_addr, idx == 0,
+                                                idx == (num - 1), m->buf,
+                                                m->len);
+               if (ret)
+                       break;
+       }
+out:
+       qup_i2c_change_state(qup, QUP_RESET_STATE);
+       return ret;
+}
+
+static int qup_i2c_enable_clocks(struct udevice *dev, struct qup_i2c_priv *qup)
+{
+       int ret;
+
+       ret = clk_enable(&qup->core);
+       if (ret) {
+               dev_err(dev, "clk_enable failed %d\n", ret);
+               return ret;
+       }
+
+       ret = clk_enable(&qup->iface);
+       if (ret) {
+               dev_err(dev, "clk_enable failed %d\n", ret);
+               return ret;
+       }
+
+       return 0;
+}
+
+static int qup_i2c_probe(struct udevice *dev)
+{
+       static const int blk_sizes[] = {4, 16, 32};
+       struct qup_i2c_priv *qup = dev_get_priv(dev);
+       u32 io_mode, hw_ver, size, size_idx;
+       int ret;
+
+       qup->base = (phys_addr_t)dev_read_addr_ptr(dev);
+       if (!qup->base)
+               return -EINVAL;
+
+       ret = clk_get_by_name(dev, "core", &qup->core);
+       if (ret) {
+               pr_err("clk_get_by_name(core) failed: %d\n", ret);
+               return ret;
+       }
+       ret = clk_get_by_name(dev, "iface", &qup->iface);
+       if (ret) {
+               pr_err("clk_get_by_name(iface) failed: %d\n", ret);
+               return ret;
+       }
+       qup_i2c_enable_clocks(dev, qup);
+
+       writel(1, qup->base + QUP_SW_RESET);
+       ret = qup_i2c_poll_state_valid(qup);
+       if (ret)
+               return ret;
+
+       hw_ver = readl(qup->base + QUP_HW_VERSION);
+       dev_dbg(dev, "Revision %x\n", hw_ver);
+
+       io_mode = readl(qup->base + QUP_IO_MODE);
+
+       /*
+        * The block/fifo size w.r.t. 'actual data' is 1/2 due to 'tag'
+        * associated with each byte written/received
+        */
+       size_idx = QUP_OUTPUT_BLOCK_SIZE(io_mode);
+       if (size_idx >= ARRAY_SIZE(blk_sizes)) {
+               ret = -EIO;
+               return ret;
+       }
+       size = QUP_OUTPUT_FIFO_SIZE(io_mode);
+       qup->out_fifo_sz = blk_sizes[size_idx] * (2 << size);
+
+       size_idx = QUP_INPUT_BLOCK_SIZE(io_mode);
+       if (size_idx >= ARRAY_SIZE(blk_sizes)) {
+               ret = -EIO;
+               return ret;
+       }
+       size = QUP_INPUT_FIFO_SIZE(io_mode);
+       qup->in_fifo_sz = blk_sizes[size_idx] * (2 << size);
+
+       dev_dbg(dev, "IN:fifo:%d, OUT:fifo:%d\n", qup->in_fifo_sz,
+               qup->out_fifo_sz);
+
+       return 0;
+}
+
+static int qup_i2c_set_bus_speed(struct udevice *dev, unsigned int clk_freq)
+{
+       struct qup_i2c_priv *qup = dev_get_priv(dev);
+       unsigned int src_clk_freq;
+       int fs_div, hs_div;
+
+       /* We support frequencies up to FAST Mode Plus (1MHz) */
+       if (!clk_freq || clk_freq > I2C_SPEED_FAST_PLUS_RATE) {
+               dev_err(dev, "clock frequency not supported %d\n", clk_freq);
+               return -EINVAL;
+       }
+
+       src_clk_freq = clk_get_rate(&qup->iface);
+       if ((int)src_clk_freq < 0) {
+               src_clk_freq = DEFAULT_SRC_CLK;
+               dev_dbg(dev, "using default core freq %d\n", src_clk_freq);
+       }
+
+       dev_dbg(dev, "src_clk_freq %u\n", src_clk_freq);
+       dev_dbg(dev, "clk_freq     %u\n", clk_freq);
+
+       hs_div = 3;
+       if (clk_freq <= I2C_SPEED_STANDARD_RATE) {
+               fs_div = ((src_clk_freq / clk_freq) / 2) - 3;
+               qup->clk_ctl = (hs_div << 8) | (fs_div & 0xff);
+       } else {
+               /* 33%/66% duty cycle */
+               fs_div = ((src_clk_freq / clk_freq) - 6) * 2 / 3;
+               qup->clk_ctl = ((fs_div / 2) << 16) | (hs_div << 8) | (fs_div & 
0xff);
+       }
+
+       dev_dbg(dev, "clk_ctl      %u\n", qup->clk_ctl);
+
+       return 0;
+}
+
+/* Probe to see if a chip is present. */
+static int qup_i2c_probe_chip(struct udevice *dev, uint chip_addr,
+                             uint chip_flags)
+{
+       struct qup_i2c_priv *qup = dev_get_priv(dev);
+       u32 hw_ver = readl(qup->base + QUP_HW_VERSION);
+
+       return hw_ver ? 0 : -1;
+}
+
+static const struct dm_i2c_ops qup_i2c_ops = {
+       .xfer           = qup_i2c_xfer_v2,
+       .probe_chip     = qup_i2c_probe_chip,
+       .set_bus_speed  = qup_i2c_set_bus_speed,
+};
+
+static const struct udevice_id qup_i2c_ids[] = {
+       { .compatible = "qcom,i2c-qup-v2.1.1" },
+       { .compatible = "qcom,i2c-qup-v2.2.1" },
+       { .compatible = "qcom,i2c-qup" },
+       {}
+};
+
+U_BOOT_DRIVER(i2c_qup) = {
+       .name   = "i2c_qup",
+       .id     = UCLASS_I2C,
+       .of_match = qup_i2c_ids,
+       .probe  = qup_i2c_probe,
+       .priv_auto = sizeof(struct qup_i2c_priv),
+       .ops    = &qup_i2c_ops,
+};
-- 
2.34.1

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