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u-boot/drivers/i2c/mxc_i2c.c
Stefan Roese 29caf9305b cyclic: Use schedule() instead of WATCHDOG_RESET() 
Globally replace all occurances of WATCHDOG_RESET() with schedule(),
which handles the HW_WATCHDOG functionality and the cyclic
infrastructure.

Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Tom Rini <trini@konsulko.com> [am335x_evm, mx6cuboxi, rpi_3,dra7xx_evm, pine64_plus, am65x_evm, j721e_evm]
2022-09-18 10:26:33 +02:00

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27 KiB
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// SPDX-License-Identifier: GPL-2.0+
/*
* i2c driver for Freescale i.MX series
*
* (c) 2007 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
* (c) 2011 Marek Vasut <marek.vasut@gmail.com>
* Copyright 2020 NXP
*
* Based on i2c-imx.c from linux kernel:
* Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de>
* Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de>
* Copyright (C) 2007 RightHand Technologies, Inc.
* Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
*
*/
#include <common.h>
#include <log.h>
#include <asm/arch/clock.h>
#include <asm/arch/imx-regs.h>
#include <asm/global_data.h>
#include <dm/device_compat.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <asm/mach-imx/mxc_i2c.h>
#include <asm/mach-imx/sys_proto.h>
#include <asm/io.h>
#include <i2c.h>
#include <watchdog.h>
#include <dm.h>
#include <dm/pinctrl.h>
#include <fdtdec.h>
DECLARE_GLOBAL_DATA_PTR;
#define I2C_QUIRK_FLAG (1 << 0)
#define IMX_I2C_REGSHIFT 2
#define VF610_I2C_REGSHIFT 0
#define I2C_EARLY_INIT_INDEX 0
#ifdef CONFIG_SYS_I2C_IFDR_DIV
#define I2C_IFDR_DIV_CONSERVATIVE CONFIG_SYS_I2C_IFDR_DIV
#else
#define I2C_IFDR_DIV_CONSERVATIVE 0x7e
#endif
/* Register index */
#define IADR 0
#define IFDR 1
#define I2CR 2
#define I2SR 3
#define I2DR 4
#define I2CR_IIEN (1 << 6)
#define I2CR_MSTA (1 << 5)
#define I2CR_MTX (1 << 4)
#define I2CR_TX_NO_AK (1 << 3)
#define I2CR_RSTA (1 << 2)
#define I2SR_ICF (1 << 7)
#define I2SR_IBB (1 << 5)
#define I2SR_IAL (1 << 4)
#define I2SR_IIF (1 << 1)
#define I2SR_RX_NO_AK (1 << 0)
#ifdef I2C_QUIRK_REG
#define I2CR_IEN (0 << 7)
#define I2CR_IDIS (1 << 7)
#define I2SR_IIF_CLEAR (1 << 1)
#else
#define I2CR_IEN (1 << 7)
#define I2CR_IDIS (0 << 7)
#define I2SR_IIF_CLEAR (0 << 1)
#endif
#ifdef I2C_QUIRK_REG
static u16 i2c_clk_div[60][2] = {
{ 20, 0x00 }, { 22, 0x01 }, { 24, 0x02 }, { 26, 0x03 },
{ 28, 0x04 }, { 30, 0x05 }, { 32, 0x09 }, { 34, 0x06 },
{ 36, 0x0A }, { 40, 0x07 }, { 44, 0x0C }, { 48, 0x0D },
{ 52, 0x43 }, { 56, 0x0E }, { 60, 0x45 }, { 64, 0x12 },
{ 68, 0x0F }, { 72, 0x13 }, { 80, 0x14 }, { 88, 0x15 },
{ 96, 0x19 }, { 104, 0x16 }, { 112, 0x1A }, { 128, 0x17 },
{ 136, 0x4F }, { 144, 0x1C }, { 160, 0x1D }, { 176, 0x55 },
{ 192, 0x1E }, { 208, 0x56 }, { 224, 0x22 }, { 228, 0x24 },
{ 240, 0x1F }, { 256, 0x23 }, { 288, 0x5C }, { 320, 0x25 },
{ 384, 0x26 }, { 448, 0x2A }, { 480, 0x27 }, { 512, 0x2B },
{ 576, 0x2C }, { 640, 0x2D }, { 768, 0x31 }, { 896, 0x32 },
{ 960, 0x2F }, { 1024, 0x33 }, { 1152, 0x34 }, { 1280, 0x35 },
{ 1536, 0x36 }, { 1792, 0x3A }, { 1920, 0x37 }, { 2048, 0x3B },
{ 2304, 0x3C }, { 2560, 0x3D }, { 3072, 0x3E }, { 3584, 0x7A },
{ 3840, 0x3F }, { 4096, 0x7B }, { 5120, 0x7D }, { 6144, 0x7E },
};
#else
static u16 i2c_clk_div[50][2] = {
{ 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 },
{ 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 },
{ 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 },
{ 56, 0x29 }, { 60, 0x06 }, { 64, 0x2A }, { 72, 0x2B },
{ 80, 0x2C }, { 88, 0x09 }, { 96, 0x2D }, { 104, 0x0A },
{ 112, 0x2E }, { 128, 0x2F }, { 144, 0x0C }, { 160, 0x30 },
{ 192, 0x31 }, { 224, 0x32 }, { 240, 0x0F }, { 256, 0x33 },
{ 288, 0x10 }, { 320, 0x34 }, { 384, 0x35 }, { 448, 0x36 },
{ 480, 0x13 }, { 512, 0x37 }, { 576, 0x14 }, { 640, 0x38 },
{ 768, 0x39 }, { 896, 0x3A }, { 960, 0x17 }, { 1024, 0x3B },
{ 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E },
{ 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D },
{ 3072, 0x1E }, { 3840, 0x1F }
};
#endif
/*
* Calculate and set proper clock divider
*/
static uint8_t i2c_imx_get_clk(struct mxc_i2c_bus *i2c_bus, unsigned int rate)
{
unsigned int i2c_clk_rate;
unsigned int div;
u8 clk_div;
#if defined(CONFIG_MX31)
struct clock_control_regs *sc_regs =
(struct clock_control_regs *)CCM_BASE;
/* start the required I2C clock */
writel(readl(&sc_regs->cgr0) | (3 << CONFIG_SYS_I2C_CLK_OFFSET),
&sc_regs->cgr0);
#endif
/* Divider value calculation */
#if CONFIG_IS_ENABLED(CLK)
i2c_clk_rate = clk_get_rate(&i2c_bus->per_clk);
#else
i2c_clk_rate = mxc_get_clock(MXC_I2C_CLK);
#endif
div = (i2c_clk_rate + rate - 1) / rate;
if (div < i2c_clk_div[0][0])
clk_div = 0;
else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
clk_div = ARRAY_SIZE(i2c_clk_div) - 1;
else
for (clk_div = 0; i2c_clk_div[clk_div][0] < div; clk_div++)
;
/* Store divider value */
return clk_div;
}
/*
* Set I2C Bus speed
*/
static int bus_i2c_set_bus_speed(struct mxc_i2c_bus *i2c_bus, int speed)
{
ulong base = i2c_bus->base;
bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
u8 clk_idx = i2c_imx_get_clk(i2c_bus, speed);
u8 idx = i2c_clk_div[clk_idx][1];
int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
if (!base)
return -EINVAL;
/* Store divider value */
writeb(idx, base + (IFDR << reg_shift));
/* Reset module */
writeb(I2CR_IDIS, base + (I2CR << reg_shift));
writeb(0, base + (I2SR << reg_shift));
return 0;
}
#define ST_BUS_IDLE (0 | (I2SR_IBB << 8))
#define ST_BUS_BUSY (I2SR_IBB | (I2SR_IBB << 8))
#define ST_IIF (I2SR_IIF | (I2SR_IIF << 8))
static int wait_for_sr_state(struct mxc_i2c_bus *i2c_bus, unsigned state)
{
unsigned sr;
ulong elapsed;
bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
ulong base = i2c_bus->base;
ulong start_time = get_timer(0);
for (;;) {
sr = readb(base + (I2SR << reg_shift));
if (sr & I2SR_IAL) {
if (quirk)
writeb(sr | I2SR_IAL, base +
(I2SR << reg_shift));
else
writeb(sr & ~I2SR_IAL, base +
(I2SR << reg_shift));
printf("%s: Arbitration lost sr=%x cr=%x state=%x\n",
__func__, sr, readb(base + (I2CR << reg_shift)),
state);
return -ERESTART;
}
if ((sr & (state >> 8)) == (unsigned char)state)
return sr;
schedule();
elapsed = get_timer(start_time);
if (elapsed > (CONFIG_SYS_HZ / 10)) /* .1 seconds */
break;
}
printf("%s: failed sr=%x cr=%x state=%x\n", __func__,
sr, readb(base + (I2CR << reg_shift)), state);
return -ETIMEDOUT;
}
static int tx_byte(struct mxc_i2c_bus *i2c_bus, u8 byte)
{
int ret;
int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
ulong base = i2c_bus->base;
writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
writeb(byte, base + (I2DR << reg_shift));
ret = wait_for_sr_state(i2c_bus, ST_IIF);
if (ret < 0)
return ret;
if (ret & I2SR_RX_NO_AK)
return -EREMOTEIO;
return 0;
}
/*
* Stub implementations for outer i2c slave operations.
*/
void __i2c_force_reset_slave(void)
{
}
void i2c_force_reset_slave(void)
__attribute__((weak, alias("__i2c_force_reset_slave")));
/*
* Stop I2C transaction
*/
static void i2c_imx_stop(struct mxc_i2c_bus *i2c_bus)
{
int ret;
int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
ulong base = i2c_bus->base;
unsigned int temp = readb(base + (I2CR << reg_shift));
temp &= ~(I2CR_MSTA | I2CR_MTX);
writeb(temp, base + (I2CR << reg_shift));
ret = wait_for_sr_state(i2c_bus, ST_BUS_IDLE);
if (ret < 0)
printf("%s:trigger stop failed\n", __func__);
}
/*
* Send start signal, chip address and
* write register address
*/
static int i2c_init_transfer_(struct mxc_i2c_bus *i2c_bus, u8 chip,
u32 addr, int alen)
{
unsigned int temp;
int ret;
bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
ulong base = i2c_bus->base;
int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
/* Reset i2c slave */
i2c_force_reset_slave();
/* Enable I2C controller */
if (quirk)
ret = readb(base + (I2CR << reg_shift)) & I2CR_IDIS;
else
ret = !(readb(base + (I2CR << reg_shift)) & I2CR_IEN);
if (ret) {
writeb(I2CR_IEN, base + (I2CR << reg_shift));
/* Wait for controller to be stable */
udelay(50);
}
if (readb(base + (IADR << reg_shift)) == (chip << 1))
writeb((chip << 1) ^ 2, base + (IADR << reg_shift));
writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
ret = wait_for_sr_state(i2c_bus, ST_BUS_IDLE);
if (ret < 0)
return ret;
/* Start I2C transaction */
temp = readb(base + (I2CR << reg_shift));
temp |= I2CR_MSTA;
writeb(temp, base + (I2CR << reg_shift));
ret = wait_for_sr_state(i2c_bus, ST_BUS_BUSY);
if (ret < 0)
return ret;
temp |= I2CR_MTX | I2CR_TX_NO_AK;
writeb(temp, base + (I2CR << reg_shift));
if (alen >= 0) {
/* write slave address */
ret = tx_byte(i2c_bus, chip << 1);
if (ret < 0)
return ret;
while (alen--) {
ret = tx_byte(i2c_bus, (addr >> (alen * 8)) & 0xff);
if (ret < 0)
return ret;
}
}
return 0;
}
#if !defined(I2C2_BASE_ADDR)
#define I2C2_BASE_ADDR 0
#endif
#if !defined(I2C3_BASE_ADDR)
#define I2C3_BASE_ADDR 0
#endif
#if !defined(I2C4_BASE_ADDR)
#define I2C4_BASE_ADDR 0
#endif
#if !defined(I2C5_BASE_ADDR)
#define I2C5_BASE_ADDR 0
#endif
#if !defined(I2C6_BASE_ADDR)
#define I2C6_BASE_ADDR 0
#endif
#if !defined(I2C7_BASE_ADDR)
#define I2C7_BASE_ADDR 0
#endif
#if !defined(I2C8_BASE_ADDR)
#define I2C8_BASE_ADDR 0
#endif
static struct mxc_i2c_bus mxc_i2c_buses[] = {
#if defined(CONFIG_ARCH_LS1021A) || defined(CONFIG_VF610) || \
defined(CONFIG_FSL_LAYERSCAPE)
{ 0, I2C1_BASE_ADDR, I2C_QUIRK_FLAG },
{ 1, I2C2_BASE_ADDR, I2C_QUIRK_FLAG },
{ 2, I2C3_BASE_ADDR, I2C_QUIRK_FLAG },
{ 3, I2C4_BASE_ADDR, I2C_QUIRK_FLAG },
{ 4, I2C5_BASE_ADDR, I2C_QUIRK_FLAG },
{ 5, I2C6_BASE_ADDR, I2C_QUIRK_FLAG },
{ 6, I2C7_BASE_ADDR, I2C_QUIRK_FLAG },
{ 7, I2C8_BASE_ADDR, I2C_QUIRK_FLAG },
#else
{ 0, I2C1_BASE_ADDR, 0 },
{ 1, I2C2_BASE_ADDR, 0 },
{ 2, I2C3_BASE_ADDR, 0 },
{ 3, I2C4_BASE_ADDR, 0 },
{ 4, I2C5_BASE_ADDR, 0 },
{ 5, I2C6_BASE_ADDR, 0 },
{ 6, I2C7_BASE_ADDR, 0 },
{ 7, I2C8_BASE_ADDR, 0 },
#endif
};
#if !CONFIG_IS_ENABLED(DM_I2C)
int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
{
if (i2c_bus && i2c_bus->idle_bus_fn)
return i2c_bus->idle_bus_fn(i2c_bus->idle_bus_data);
return 0;
}
#else
/*
* See Linux Documentation/devicetree/bindings/i2c/i2c-imx.txt
* "
* scl-gpios: specify the gpio related to SCL pin
* sda-gpios: specify the gpio related to SDA pin
* add pinctrl to configure i2c pins to gpio function for i2c
* bus recovery, call it "gpio" state
* "
*
* The i2c_idle_bus is an implementation following Linux Kernel.
*/
int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
{
struct udevice *bus = i2c_bus->bus;
struct dm_i2c_bus *i2c = dev_get_uclass_priv(bus);
struct gpio_desc *scl_gpio = &i2c_bus->scl_gpio;
struct gpio_desc *sda_gpio = &i2c_bus->sda_gpio;
int sda, scl, idle_sclks;
int i, ret = 0;
ulong elapsed, start_time;
if (pinctrl_select_state(bus, "gpio")) {
dev_dbg(bus, "Can not to switch to use gpio pinmux\n");
/*
* GPIO pinctrl for i2c force idle is not a must,
* but it is strongly recommended to be used.
* Because it can help you to recover from bad
* i2c bus state. Do not return failure, because
* it is not a must.
*/
return 0;
}
dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
dm_gpio_set_dir_flags(sda_gpio, GPIOD_IS_IN);
scl = dm_gpio_get_value(scl_gpio);
sda = dm_gpio_get_value(sda_gpio);
if ((sda & scl) == 1)
goto exit; /* Bus is idle already */
/*
* In most cases it is just enough to generate 8 + 1 SCLK
* clocks to recover I2C slave device from 'stuck' state
* (when for example SW reset was performed, in the middle of
* I2C transmission).
*
* However, there are devices which send data in packets of
* N bytes (N > 1). In such case we do need N * 8 + 1 SCLK
* clocks.
*/
idle_sclks = 8 + 1;
if (i2c->max_transaction_bytes > 0)
idle_sclks = i2c->max_transaction_bytes * 8 + 1;
/* Send high and low on the SCL line */
for (i = 0; i < idle_sclks; i++) {
dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_OUT);
dm_gpio_set_value(scl_gpio, 0);
udelay(50);
dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
udelay(50);
}
start_time = get_timer(0);
for (;;) {
dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
dm_gpio_set_dir_flags(sda_gpio, GPIOD_IS_IN);
scl = dm_gpio_get_value(scl_gpio);
sda = dm_gpio_get_value(sda_gpio);
if ((sda & scl) == 1)
break;
schedule();
elapsed = get_timer(start_time);
if (elapsed > (CONFIG_SYS_HZ / 5)) { /* .2 seconds */
ret = -EBUSY;
printf("%s: failed to clear bus, sda=%d scl=%d\n", __func__, sda, scl);
break;
}
}
exit:
pinctrl_select_state(bus, "default");
return ret;
}
#endif
/*
* Early init I2C for prepare read the clk through I2C.
*/
void i2c_early_init_f(void)
{
ulong base = mxc_i2c_buses[I2C_EARLY_INIT_INDEX].base;
bool quirk = mxc_i2c_buses[I2C_EARLY_INIT_INDEX].driver_data
& I2C_QUIRK_FLAG ? true : false;
int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
/* Set I2C divider value */
writeb(I2C_IFDR_DIV_CONSERVATIVE, base + (IFDR << reg_shift));
/* Reset module */
writeb(I2CR_IDIS, base + (I2CR << reg_shift));
writeb(0, base + (I2SR << reg_shift));
/* Enable I2C */
writeb(I2CR_IEN, base + (I2CR << reg_shift));
}
static int i2c_init_transfer(struct mxc_i2c_bus *i2c_bus, u8 chip,
u32 addr, int alen)
{
int retry;
int ret;
int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
if (!i2c_bus->base)
return -EINVAL;
for (retry = 0; retry < 3; retry++) {
ret = i2c_init_transfer_(i2c_bus, chip, addr, alen);
if (ret >= 0)
return 0;
i2c_imx_stop(i2c_bus);
if (ret == -EREMOTEIO)
return ret;
printf("%s: failed for chip 0x%x retry=%d\n", __func__, chip,
retry);
if (ret != -ERESTART)
/* Disable controller */
writeb(I2CR_IDIS, i2c_bus->base + (I2CR << reg_shift));
udelay(100);
if (i2c_idle_bus(i2c_bus) < 0)
break;
}
printf("%s: give up i2c_regs=0x%lx\n", __func__, i2c_bus->base);
return ret;
}
static int i2c_write_data(struct mxc_i2c_bus *i2c_bus, u8 chip, const u8 *buf,
int len)
{
int i, ret = 0;
debug("i2c_write_data: chip=0x%x, len=0x%x\n", chip, len);
debug("write_data: ");
/* use rc for counter */
for (i = 0; i < len; ++i)
debug(" 0x%02x", buf[i]);
debug("\n");
for (i = 0; i < len; i++) {
ret = tx_byte(i2c_bus, buf[i]);
if (ret < 0) {
debug("i2c_write_data(): rc=%d\n", ret);
break;
}
}
return ret;
}
/* Will generate a STOP after the last byte if "last" is true, i.e. this is the
* final message of a transaction. If not, it switches the bus back to TX mode
* and does not send a STOP, leaving the bus in a state where a repeated start
* and address can be sent for another message.
*/
static int i2c_read_data(struct mxc_i2c_bus *i2c_bus, uchar chip, uchar *buf,
int len, bool last)
{
int ret;
unsigned int temp;
int i;
int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
ulong base = i2c_bus->base;
debug("i2c_read_data: chip=0x%x, len=0x%x\n", chip, len);
/* setup bus to read data */
temp = readb(base + (I2CR << reg_shift));
temp &= ~(I2CR_MTX | I2CR_TX_NO_AK);
if (len == 1)
temp |= I2CR_TX_NO_AK;
writeb(temp, base + (I2CR << reg_shift));
writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
/* dummy read to clear ICF */
readb(base + (I2DR << reg_shift));
/* read data */
for (i = 0; i < len; i++) {
ret = wait_for_sr_state(i2c_bus, ST_IIF);
if (ret < 0) {
debug("i2c_read_data(): ret=%d\n", ret);
i2c_imx_stop(i2c_bus);
return ret;
}
if (i == (len - 1)) {
/* Final byte has already been received by master! When
* we read it from I2DR, the master will start another
* cycle. We must program it first to send a STOP or
* switch to TX to avoid this.
*/
if (last) {
i2c_imx_stop(i2c_bus);
} else {
/* Final read, no stop, switch back to tx */
temp = readb(base + (I2CR << reg_shift));
temp |= I2CR_MTX | I2CR_TX_NO_AK;
writeb(temp, base + (I2CR << reg_shift));
}
} else if (i == (len - 2)) {
/* Master has already recevied penultimate byte. When
* we read it from I2DR, master will start RX of final
* byte. We must set TX_NO_AK now so it does not ACK
* that final byte.
*/
temp = readb(base + (I2CR << reg_shift));
temp |= I2CR_TX_NO_AK;
writeb(temp, base + (I2CR << reg_shift));
}
writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
buf[i] = readb(base + (I2DR << reg_shift));
}
/* reuse ret for counter*/
for (ret = 0; ret < len; ++ret)
debug(" 0x%02x", buf[ret]);
debug("\n");
/* It is not clear to me that this is necessary */
if (last)
i2c_imx_stop(i2c_bus);
return 0;
}
int __enable_i2c_clk(unsigned char enable, unsigned int i2c_num)
{
return 1;
}
int enable_i2c_clk(unsigned char enable, unsigned int i2c_num)
__attribute__((weak, alias("__enable_i2c_clk")));
#if !CONFIG_IS_ENABLED(DM_I2C)
/*
* Read data from I2C device
*
* The transactions use the syntax defined in the Linux kernel I2C docs.
*
* If alen is > 0, then this function will send a transaction of the form:
* S Chip Wr [A] Addr [A] S Chip Rd [A] [data] A ... NA P
* This is a normal I2C register read: writing the register address, then doing
* a repeated start and reading the data.
*
* If alen == 0, then we get this transaction:
* S Chip Wr [A] S Chip Rd [A] [data] A ... NA P
* This is somewhat unusual, though valid, transaction. It addresses the chip
* in write mode, but doesn't actually write any register address or data, then
* does a repeated start and reads data.
*
* If alen < 0, then we get this transaction:
* S Chip Rd [A] [data] A ... NA P
* The chip is addressed in read mode and then data is read. No register
* address is written first. This is perfectly valid on most devices and
* required on some (usually those that don't act like an array of registers).
*/
static int bus_i2c_read(struct mxc_i2c_bus *i2c_bus, u8 chip, u32 addr,
int alen, u8 *buf, int len)
{
int ret = 0;
u32 temp;
int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
ulong base = i2c_bus->base;
ret = i2c_init_transfer(i2c_bus, chip, addr, alen);
if (ret < 0)
return ret;
if (alen >= 0) {
temp = readb(base + (I2CR << reg_shift));
temp |= I2CR_RSTA;
writeb(temp, base + (I2CR << reg_shift));
}
ret = tx_byte(i2c_bus, (chip << 1) | 1);
if (ret < 0) {
i2c_imx_stop(i2c_bus);
return ret;
}
ret = i2c_read_data(i2c_bus, chip, buf, len, true);
i2c_imx_stop(i2c_bus);
return ret;
}
/*
* Write data to I2C device
*
* If alen > 0, we get this transaction:
* S Chip Wr [A] addr [A] data [A] ... [A] P
* An ordinary write register command.
*
* If alen == 0, then we get this:
* S Chip Wr [A] data [A] ... [A] P
* This is a simple I2C write.
*
* If alen < 0, then we get this:
* S data [A] ... [A] P
* This is most likely NOT something that should be used. It doesn't send the
* chip address first, so in effect, the first byte of data will be used as the
* address.
*/
static int bus_i2c_write(struct mxc_i2c_bus *i2c_bus, u8 chip, u32 addr,
int alen, const u8 *buf, int len)
{
int ret = 0;
ret = i2c_init_transfer(i2c_bus, chip, addr, alen);
if (ret < 0)
return ret;
ret = i2c_write_data(i2c_bus, chip, buf, len);
i2c_imx_stop(i2c_bus);
return ret;
}
struct mxc_i2c_bus *i2c_get_base(struct i2c_adapter *adap)
{
return &mxc_i2c_buses[adap->hwadapnr];
}
static int mxc_i2c_read(struct i2c_adapter *adap, uint8_t chip,
uint addr, int alen, uint8_t *buffer,
int len)
{
return bus_i2c_read(i2c_get_base(adap), chip, addr, alen, buffer, len);
}
static int mxc_i2c_write(struct i2c_adapter *adap, uint8_t chip,
uint addr, int alen, uint8_t *buffer,
int len)
{
return bus_i2c_write(i2c_get_base(adap), chip, addr, alen, buffer, len);
}
/*
* Test if a chip at a given address responds (probe the chip)
*/
static int mxc_i2c_probe(struct i2c_adapter *adap, uint8_t chip)
{
return bus_i2c_write(i2c_get_base(adap), chip, 0, 0, NULL, 0);
}
void bus_i2c_init(int index, int speed, int unused,
int (*idle_bus_fn)(void *p), void *idle_bus_data)
{
int ret;
if (index >= ARRAY_SIZE(mxc_i2c_buses)) {
debug("Error i2c index\n");
return;
}
if (CONFIG_IS_ENABLED(IMX_MODULE_FUSE)) {
if (i2c_fused((ulong)mxc_i2c_buses[index].base)) {
printf("SoC fuse indicates I2C@0x%lx is unavailable.\n",
(ulong)mxc_i2c_buses[index].base);
return;
}
}
/*
* Warning: Be careful to allow the assignment to a static
* variable here. This function could be called while U-Boot is
* still running in flash memory. So such assignment is equal
* to write data to flash without erasing.
*/
if (idle_bus_fn)
mxc_i2c_buses[index].idle_bus_fn = idle_bus_fn;
if (idle_bus_data)
mxc_i2c_buses[index].idle_bus_data = idle_bus_data;
ret = enable_i2c_clk(1, index);
if (ret < 0) {
debug("I2C-%d clk fail to enable.\n", index);
return;
}
bus_i2c_set_bus_speed(&mxc_i2c_buses[index], speed);
}
/*
* Init I2C Bus
*/
static void mxc_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
{
bus_i2c_init(adap->hwadapnr, speed, slaveaddr, NULL, NULL);
}
/*
* Set I2C Speed
*/
static u32 mxc_i2c_set_bus_speed(struct i2c_adapter *adap, uint speed)
{
return bus_i2c_set_bus_speed(i2c_get_base(adap), speed);
}
/*
* Register mxc i2c adapters
*/
#ifdef CONFIG_SYS_I2C_MXC_I2C1
U_BOOT_I2C_ADAP_COMPLETE(mxc0, mxc_i2c_init, mxc_i2c_probe,
mxc_i2c_read, mxc_i2c_write,
mxc_i2c_set_bus_speed,
CONFIG_SYS_MXC_I2C1_SPEED,
CONFIG_SYS_MXC_I2C1_SLAVE, 0)
#endif
#ifdef CONFIG_SYS_I2C_MXC_I2C2
U_BOOT_I2C_ADAP_COMPLETE(mxc1, mxc_i2c_init, mxc_i2c_probe,
mxc_i2c_read, mxc_i2c_write,
mxc_i2c_set_bus_speed,
CONFIG_SYS_MXC_I2C2_SPEED,
CONFIG_SYS_MXC_I2C2_SLAVE, 1)
#endif
#ifdef CONFIG_SYS_I2C_MXC_I2C3
U_BOOT_I2C_ADAP_COMPLETE(mxc2, mxc_i2c_init, mxc_i2c_probe,
mxc_i2c_read, mxc_i2c_write,
mxc_i2c_set_bus_speed,
CONFIG_SYS_MXC_I2C3_SPEED,
CONFIG_SYS_MXC_I2C3_SLAVE, 2)
#endif
#ifdef CONFIG_SYS_I2C_MXC_I2C4
U_BOOT_I2C_ADAP_COMPLETE(mxc3, mxc_i2c_init, mxc_i2c_probe,
mxc_i2c_read, mxc_i2c_write,
mxc_i2c_set_bus_speed,
CONFIG_SYS_MXC_I2C4_SPEED,
CONFIG_SYS_MXC_I2C4_SLAVE, 3)
#endif
#ifdef CONFIG_SYS_I2C_MXC_I2C5
U_BOOT_I2C_ADAP_COMPLETE(mxc4, mxc_i2c_init, mxc_i2c_probe,
mxc_i2c_read, mxc_i2c_write,
mxc_i2c_set_bus_speed,
CONFIG_SYS_MXC_I2C5_SPEED,
CONFIG_SYS_MXC_I2C5_SLAVE, 4)
#endif
#ifdef CONFIG_SYS_I2C_MXC_I2C6
U_BOOT_I2C_ADAP_COMPLETE(mxc5, mxc_i2c_init, mxc_i2c_probe,
mxc_i2c_read, mxc_i2c_write,
mxc_i2c_set_bus_speed,
CONFIG_SYS_MXC_I2C6_SPEED,
CONFIG_SYS_MXC_I2C6_SLAVE, 5)
#endif
#ifdef CONFIG_SYS_I2C_MXC_I2C7
U_BOOT_I2C_ADAP_COMPLETE(mxc6, mxc_i2c_init, mxc_i2c_probe,
mxc_i2c_read, mxc_i2c_write,
mxc_i2c_set_bus_speed,
CONFIG_SYS_MXC_I2C7_SPEED,
CONFIG_SYS_MXC_I2C7_SLAVE, 6)
#endif
#ifdef CONFIG_SYS_I2C_MXC_I2C8
U_BOOT_I2C_ADAP_COMPLETE(mxc7, mxc_i2c_init, mxc_i2c_probe,
mxc_i2c_read, mxc_i2c_write,
mxc_i2c_set_bus_speed,
CONFIG_SYS_MXC_I2C8_SPEED,
CONFIG_SYS_MXC_I2C8_SLAVE, 7)
#endif
#else
static int mxc_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
{
struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
return bus_i2c_set_bus_speed(i2c_bus, speed);
}
static int mxc_i2c_probe(struct udevice *bus)
{
struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
const void *fdt = gd->fdt_blob;
int node = dev_of_offset(bus);
fdt_addr_t addr;
int ret, ret2;
i2c_bus->driver_data = dev_get_driver_data(bus);
addr = dev_read_addr(bus);
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
if (CONFIG_IS_ENABLED(IMX_MODULE_FUSE)) {
if (i2c_fused((ulong)addr)) {
printf("SoC fuse indicates I2C@0x%lx is unavailable.\n",
(ulong)addr);
return -ENODEV;
}
}
i2c_bus->base = addr;
i2c_bus->index = dev_seq(bus);
i2c_bus->bus = bus;
/* Enable clk */
#if CONFIG_IS_ENABLED(CLK)
ret = clk_get_by_index(bus, 0, &i2c_bus->per_clk);
if (ret) {
printf("Failed to get i2c clk\n");
return ret;
}
ret = clk_enable(&i2c_bus->per_clk);
if (ret) {
printf("Failed to enable i2c clk\n");
return ret;
}
#else
ret = enable_i2c_clk(1, dev_seq(bus));
if (ret < 0)
return ret;
#endif
/*
* See Documentation/devicetree/bindings/i2c/i2c-imx.txt
* Use gpio to force bus idle when necessary.
*/
ret = fdt_stringlist_search(fdt, node, "pinctrl-names", "gpio");
if (ret < 0) {
debug("i2c bus %d at 0x%2lx, no gpio pinctrl state.\n",
dev_seq(bus), i2c_bus->base);
} else {
ret = gpio_request_by_name_nodev(offset_to_ofnode(node),
"scl-gpios", 0, &i2c_bus->scl_gpio,
GPIOD_IS_OUT);
ret2 = gpio_request_by_name_nodev(offset_to_ofnode(node),
"sda-gpios", 0, &i2c_bus->sda_gpio,
GPIOD_IS_OUT);
if (!dm_gpio_is_valid(&i2c_bus->sda_gpio) ||
!dm_gpio_is_valid(&i2c_bus->scl_gpio) ||
ret || ret2) {
dev_err(bus,
"i2c bus %d at 0x%2lx, fail to request scl/sda gpio\n",
dev_seq(bus), i2c_bus->base);
return -EINVAL;
}
}
/*
* Pinmux settings are in board file now, until pinmux is supported,
* we can set pinmux here in probe function.
*/
debug("i2c : controller bus %d at %lu , speed %d: ",
dev_seq(bus), i2c_bus->base,
i2c_bus->speed);
return 0;
}
/* Sends: S Addr Wr [A|NA] P */
static int mxc_i2c_probe_chip(struct udevice *bus, u32 chip_addr,
u32 chip_flags)
{
int ret;
struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
ret = i2c_init_transfer(i2c_bus, chip_addr, 0, 0);
if (ret < 0) {
debug("%s failed, ret = %d\n", __func__, ret);
return ret;
}
i2c_imx_stop(i2c_bus);
return 0;
}
static int mxc_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
{
struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
int ret = 0;
ulong base = i2c_bus->base;
int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
int read_mode;
/* Here address len is set to -1 to not send any address at first.
* Otherwise i2c_init_transfer will send the chip address with write
* mode set. This is wrong if the 1st message is read.
*/
ret = i2c_init_transfer(i2c_bus, msg->addr, 0, -1);
if (ret < 0) {
debug("i2c_init_transfer error: %d\n", ret);
return ret;
}
read_mode = -1; /* So it's always different on the first message */
for (; nmsgs > 0; nmsgs--, msg++) {
const int msg_is_read = !!(msg->flags & I2C_M_RD);
debug("i2c_xfer: chip=0x%x, len=0x%x, dir=%c\n", msg->addr,
msg->len, msg_is_read ? 'R' : 'W');
if (msg_is_read != read_mode) {
/* Send repeated start if not 1st message */
if (read_mode != -1) {
debug("i2c_xfer: [RSTART]\n");
ret = readb(base + (I2CR << reg_shift));
ret |= I2CR_RSTA;
writeb(ret, base + (I2CR << reg_shift));
}
debug("i2c_xfer: [ADDR %02x | %c]\n", msg->addr,
msg_is_read ? 'R' : 'W');
ret = tx_byte(i2c_bus, (msg->addr << 1) | msg_is_read);
if (ret < 0) {
debug("i2c_xfer: [STOP]\n");
i2c_imx_stop(i2c_bus);
break;
}
read_mode = msg_is_read;
}
if (msg->flags & I2C_M_RD)
ret = i2c_read_data(i2c_bus, msg->addr, msg->buf,
msg->len, nmsgs == 1 ||
(msg->flags & I2C_M_STOP));
else
ret = i2c_write_data(i2c_bus, msg->addr, msg->buf,
msg->len);
if (ret < 0)
break;
}
if (ret)
debug("i2c_write: error sending\n");
i2c_imx_stop(i2c_bus);
return ret;
}
static const struct dm_i2c_ops mxc_i2c_ops = {
.xfer = mxc_i2c_xfer,
.probe_chip = mxc_i2c_probe_chip,
.set_bus_speed = mxc_i2c_set_bus_speed,
};
static const struct udevice_id mxc_i2c_ids[] = {
{ .compatible = "fsl,imx21-i2c", },
{ .compatible = "fsl,vf610-i2c", .data = I2C_QUIRK_FLAG, },
{}
};
U_BOOT_DRIVER(i2c_mxc) = {
.name = "i2c_mxc",
.id = UCLASS_I2C,
.of_match = mxc_i2c_ids,
.probe = mxc_i2c_probe,
.priv_auto = sizeof(struct mxc_i2c_bus),
.ops = &mxc_i2c_ops,
.flags = DM_FLAG_PRE_RELOC,
};
#endif
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