[PATCH 13/14] i2c: Add support for Qualcomm I2C driver
Sumit Garg
sumit.garg at linaro.org
Fri Jan 20 13:25:35 CET 2023
Hi Heiko,
Thanks for your review.
On Fri, 20 Jan 2023 at 14:16, Heiko Schocher <hs at denx.de> wrote:
>
> 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 <mworsfold at impinj.com>
> > Signed-off-by: Mike Worsfold <mworsfold at impinj.com>
> > Signed-off-by: Sumit Garg <sumit.garg at 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.
>
> Please sort alphabetical,
Sure.
> and may you can ad here some more infos
> like link to datasheet?
>
I will try to put more info here. However, I don't think the datasheet
is available publically. This driver is inspired from its Linux
counterpart only.
> > +
> > 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-$(CONFIG_SYS_I2C_QUP) += qup_i2c.o
>
> Please sort alphabetical
>
Ack.
> > obj-$(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.garg at 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 */
>
> What means "mini core" ? May worth to add this info also in Kconfig help ?
Okay I will extend this comment as well as extend Kconfig help section too.
>
> > +#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?
>
At this point I don't think there will be any other driver including
that headerfile. So I would like to keep them here only.
> Also I2C_... names, sounds like this are common i2c names, which
> we should prevent, as this defines are used only in your driver ... or?
>
Makes sense, I will get rid of I2C_... names.
> > +
> > +/* 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.
>
Ack.
> > +#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?
>
Actually, v1 is there in the upstream Linux driver [1] but it can't be
tested until a corresponding SoC support is added in u-boot. So I
specified it as v2 for clarity and will add a comment regarding this
in the next version.
[1] https://elixir.bootlin.com/linux/v6.2-rc4/source/drivers/i2c/busses/i2c-qup.c#L1688
-Sumit
> > +{
> > + 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: hs at denx.de
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