Helo Sumit Garg,

On 20.01.23 08:17, Sumit Garg wrote:
> 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 <[email protected]>
> Signed-off-by: Mike Worsfold <[email protected]>
> Signed-off-by: Sumit Garg <[email protected]>
> ---
>  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.

Please sort alphabetical, and may you can ad here some more infos
like link to datasheet?

> +
>  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

Please sort alphabetical

>  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 <[email protected]>
> + *
> + * 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 */

What means "mini core" ? May worth to add this info also in Kconfig help ?

> +#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

May you want to move this to a sperate headerfile?

Also I2C_... names, sounds like this are common i2c names, which
we should prevent, as this defines are used only in your driver ... or?

> +
> +/* 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

None of this I2C_STATUS_X defines are used in your driver, please reomve.

> +#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)

If there is an _v2 ... but not finding a _v1 or so ... please remove the "_v2"
in the name as not necessary? Applies for other function names too... or at
least add a comment what V2 means?

> +{
> +     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,
> +};
> 

Thanks!

bye,
Heiko
-- 
DENX Software Engineering GmbH,      Managing Director: Erika Unter
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-52   Fax: +49-8142-66989-80   Email: [email protected]

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