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u-boot/drivers/i2c/mxc_i2c.c
Peng Fan e1bed80272 dm: i2c: mxc_i2c: implement i2c_idle_bus 
Implement i2c_idle_bus in driver, then setup_i2c can
be dropped for boards which enable DM_I2C/DM_GPIO/PINCTRL.
The i2c_idle_bus force bus idle flow follows setup_i2c in
arch/arm/imx-common/i2c-mxv7.c

This patch is an implementation following linux kernel patch:
"
commit 1c4b6c3bcf30d0804db0d0647d8ebeb862c6f7e5
Author: Gao Pan <b54642@freescale.com>
Date:   Fri Oct 23 20:28:54 2015 +0800

    i2c: imx: implement bus recovery

    Implement bus recovery methods for i2c-imx so we can recover from
    situations where SCL/SDA are stuck low.

    Once i2c bus SCL/SDA are stuck low during transfer, config the i2c
    pinctrl to gpio mode by calling pinctrl sleep set function, and then
    use GPIO to emulate the i2c protocol to send nine dummy clock to recover
    i2c device. After recovery, set i2c pinctrl to default group setting.
"

See Documentation/devicetree/bindings/i2c/i2c-imx.txt for detailed
description.
1. Introuduce scl_gpio/sda_gpio/bus in mxc_i2c_bus.
2. Discard the __weak attribute for i2c_idle_bus and implement it,
   since we have pinctrl driver/driver model gpio driver. We can
   use device tree, but not let board code to do this.
3. gpio state for mxc_i2c is not a must, but it is recommended. If
   there is no gpio state, driver will give tips, but not fail.
4. The i2c controller was first probed, default pinctrl state will
   be used, so when need to use gpio function, need to do
   "pinctrl_select_state(dev, "gpio")" and after force bus idle,
   need to switch back "pinctrl_select_state(dev, "default")".

This is example about how to use the gpio force bus
idle function:
"
 &i2c1 {
 	clock-frequency = <100000>;
	pinctrl-names = "default", "gpio";
 	pinctrl-0 = <&pinctrl_i2c1>;
	pinctrl-1 = <&pinctrl_i2c1_gpio>;
	scl-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
	sda-gpios = <&gpio1 29 GPIO_ACTIVE_HIGH>;
	status = "okay";
	[....]
 };

[.....]

	pinctrl_i2c1_gpio: i2c1grp_gpio {
		fsl,pins = <
			MX6UL_PAD_UART4_TX_DATA__GPIO1_IO28 0x1b8b0
			MX6UL_PAD_UART4_RX_DATA__GPIO1_IO29 0x1b8b0
		>;
	};
"

Signed-off-by: Peng Fan <van.freenix@gmail.com>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: York Sun <york.sun@nxp.com>
2016-03-28 09:22:58 +02:00

877 lines
22 KiB
C
Raw Blame History

/*
* i2c driver for Freescale i.MX series
*
* (c) 2007 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
* (c) 2011 Marek Vasut <marek.vasut@gmail.com>
*
* 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>
*
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/arch/clock.h>
#include <asm/arch/imx-regs.h>
#include <asm/errno.h>
#include <asm/imx-common/mxc_i2c.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
/* 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
#if defined(CONFIG_HARD_I2C) && !defined(CONFIG_SYS_I2C_BASE)
#error "define CONFIG_SYS_I2C_BASE to use the mxc_i2c driver"
#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
#ifndef CONFIG_SYS_MXC_I2C1_SPEED
#define CONFIG_SYS_MXC_I2C1_SPEED 100000
#endif
#ifndef CONFIG_SYS_MXC_I2C2_SPEED
#define CONFIG_SYS_MXC_I2C2_SPEED 100000
#endif
#ifndef CONFIG_SYS_MXC_I2C3_SPEED
#define CONFIG_SYS_MXC_I2C3_SPEED 100000
#endif
#ifndef CONFIG_SYS_MXC_I2C4_SPEED
#define CONFIG_SYS_MXC_I2C4_SPEED 100000
#endif
#ifndef CONFIG_SYS_MXC_I2C1_SLAVE
#define CONFIG_SYS_MXC_I2C1_SLAVE 0
#endif
#ifndef CONFIG_SYS_MXC_I2C2_SLAVE
#define CONFIG_SYS_MXC_I2C2_SLAVE 0
#endif
#ifndef CONFIG_SYS_MXC_I2C3_SLAVE
#define CONFIG_SYS_MXC_I2C3_SLAVE 0
#endif
#ifndef CONFIG_SYS_MXC_I2C4_SLAVE
#define CONFIG_SYS_MXC_I2C4_SLAVE 0
#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 */
i2c_clk_rate = mxc_get_clock(MXC_I2C_CLK);
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 -ENODEV;
/* 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;
WATCHDOG_RESET();
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 -ENODEV;
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));
/* 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;
}
#ifndef CONFIG_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 gpio_desc *scl_gpio = &i2c_bus->scl_gpio;
struct gpio_desc *sda_gpio = &i2c_bus->sda_gpio;
int sda, scl;
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 */
/* Send high and low on the SCL line */
for (i = 0; i < 9; 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;
WATCHDOG_RESET();
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
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 -ENODEV;
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 == -ENODEV)
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;
}
static int i2c_read_data(struct mxc_i2c_bus *i2c_bus, uchar chip, uchar *buf,
int len)
{
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;
}
/*
* It must generate STOP before read I2DR to prevent
* controller from generating another clock cycle
*/
if (i == (len - 1)) {
i2c_imx_stop(i2c_bus);
} else if (i == (len - 2)) {
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");
i2c_imx_stop(i2c_bus);
return 0;
}
#ifndef CONFIG_DM_I2C
/*
* Read data from I2C device
*/
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;
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);
i2c_imx_stop(i2c_bus);
return ret;
}
/*
* Write data to I2C device
*/
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;
}
#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
static struct mxc_i2c_bus mxc_i2c_buses[] = {
#if defined(CONFIG_LS102XA) || 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 },
#else
{ 0, I2C1_BASE_ADDR, 0 },
{ 1, I2C2_BASE_ADDR, 0 },
{ 2, I2C3_BASE_ADDR, 0 },
{ 3, I2C4_BASE_ADDR, 0 },
#endif
};
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);
}
int __enable_i2c_clk(unsigned char enable, unsigned i2c_num)
{
return 1;
}
int enable_i2c_clk(unsigned char enable, unsigned i2c_num)
__attribute__((weak, alias("__enable_i2c_clk")));
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;
}
/*
* 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
#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 = bus->of_offset;
fdt_addr_t addr;
int ret, ret2;
i2c_bus->driver_data = dev_get_driver_data(bus);
addr = dev_get_addr(bus);
if (addr == FDT_ADDR_T_NONE)
return -ENODEV;
i2c_bus->base = addr;
i2c_bus->index = bus->seq;
i2c_bus->bus = bus;
/* Enable clk */
ret = enable_i2c_clk(1, bus->seq);
if (ret < 0)
return ret;
/*
* See Documentation/devicetree/bindings/i2c/i2c-imx.txt
* Use gpio to force bus idle when necessary.
*/
ret = fdt_find_string(fdt, node, "pinctrl-names", "gpio");
if (ret < 0) {
dev_info(dev, "i2c bus %d at %lu, no gpio pinctrl state.\n", bus->seq, i2c_bus->base);
} else {
ret = gpio_request_by_name_nodev(fdt, node, "scl-gpios",
0, &i2c_bus->scl_gpio,
GPIOD_IS_OUT);
ret2 = gpio_request_by_name_nodev(fdt, 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(dev, "i2c bus %d at %lu, fail to request scl/sda gpio\n", bus->seq, i2c_bus->base);
return -ENODEV;
}
}
ret = i2c_idle_bus(i2c_bus);
if (ret < 0) {
/* Disable clk */
enable_i2c_clk(0, bus->seq);
return ret;
}
/*
* 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: ",
bus->seq, i2c_bus->base,
i2c_bus->speed);
return 0;
}
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;
/*
* Here the 3rd parameter addr and the 4th one alen are set to 0,
* because here we only want to send out chip address. The register
* address is wrapped in msg.
*/
ret = i2c_init_transfer(i2c_bus, msg->addr, 0, 0);
if (ret < 0) {
debug("i2c_init_transfer error: %d\n", ret);
return ret;
}
for (; nmsgs > 0; nmsgs--, msg++) {
bool next_is_read = nmsgs > 1 && (msg[1].flags & I2C_M_RD);
debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
if (msg->flags & I2C_M_RD)
ret = i2c_read_data(i2c_bus, msg->addr, msg->buf,
msg->len);
else {
ret = i2c_write_data(i2c_bus, msg->addr, msg->buf,
msg->len);
if (ret)
break;
if (next_is_read) {
/* Reuse ret */
ret = readb(base + (I2CR << reg_shift));
ret |= I2CR_RSTA;
writeb(ret, base + (I2CR << reg_shift));
ret = tx_byte(i2c_bus, (msg->addr << 1) | 1);
if (ret < 0) {
i2c_imx_stop(i2c_bus);
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_alloc_size = sizeof(struct mxc_i2c_bus),
.ops = &mxc_i2c_ops,
};
#endif
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