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u-boot/drivers/i2c/mxc_i2c.c

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/*
* 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/io.h>
#include <i2c.h>
#include <watchdog.h>
#ifdef I2C_QUIRK_REG
struct mxc_i2c_regs {
uint8_t iadr;
uint8_t ifdr;
uint8_t i2cr;
uint8_t i2sr;
uint8_t i2dr;
};
#else
struct mxc_i2c_regs {
uint32_t iadr;
uint32_t ifdr;
uint32_t i2cr;
uint32_t i2sr;
uint32_t i2dr;
};
#endif
#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_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
/*
* Calculate and set proper clock divider
*/
static uint8_t i2c_imx_get_clk(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(void *base, int speed)
{
struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
u8 clk_idx = i2c_imx_get_clk(speed);
u8 idx = i2c_clk_div[clk_idx][1];
/* Store divider value */
writeb(idx, &i2c_regs->ifdr);
/* Reset module */
writeb(I2CR_IDIS, &i2c_regs->i2cr);
writeb(0, &i2c_regs->i2sr);
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_regs *i2c_regs, unsigned state)
{
unsigned sr;
ulong elapsed;
ulong start_time = get_timer(0);
for (;;) {
sr = readb(&i2c_regs->i2sr);
if (sr & I2SR_IAL) {
#ifdef I2C_QUIRK_REG
writeb(sr | I2SR_IAL, &i2c_regs->i2sr);
#else
writeb(sr & ~I2SR_IAL, &i2c_regs->i2sr);
#endif
printf("%s: Arbitration lost sr=%x cr=%x state=%x\n",
__func__, sr, readb(&i2c_regs->i2cr), 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(&i2c_regs->i2cr), state);
return -ETIMEDOUT;
}
static int tx_byte(struct mxc_i2c_regs *i2c_regs, u8 byte)
{
int ret;
writeb(I2SR_IIF_CLEAR, &i2c_regs->i2sr);
writeb(byte, &i2c_regs->i2dr);
ret = wait_for_sr_state(i2c_regs, ST_IIF);
if (ret < 0)
return ret;
if (ret & I2SR_RX_NO_AK)
return -ENODEV;
return 0;
}
/*
* Stop I2C transaction
*/
static void i2c_imx_stop(struct mxc_i2c_regs *i2c_regs)
{
int ret;
unsigned int temp = readb(&i2c_regs->i2cr);
temp &= ~(I2CR_MSTA | I2CR_MTX);
writeb(temp, &i2c_regs->i2cr);
ret = wait_for_sr_state(i2c_regs, 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_regs *i2c_regs,
uchar chip, uint addr, int alen)
{
unsigned int temp;
int ret;
/* Enable I2C controller */
#ifdef I2C_QUIRK_REG
if (readb(&i2c_regs->i2cr) & I2CR_IDIS) {
#else
if (!(readb(&i2c_regs->i2cr) & I2CR_IEN)) {
#endif
writeb(I2CR_IEN, &i2c_regs->i2cr);
/* Wait for controller to be stable */
udelay(50);
}
if (readb(&i2c_regs->iadr) == (chip << 1))
writeb((chip << 1) ^ 2, &i2c_regs->iadr);
writeb(I2SR_IIF_CLEAR, &i2c_regs->i2sr);
ret = wait_for_sr_state(i2c_regs, ST_BUS_IDLE);
if (ret < 0)
return ret;
/* Start I2C transaction */
temp = readb(&i2c_regs->i2cr);
temp |= I2CR_MSTA;
writeb(temp, &i2c_regs->i2cr);
ret = wait_for_sr_state(i2c_regs, ST_BUS_BUSY);
if (ret < 0)
return ret;
temp |= I2CR_MTX | I2CR_TX_NO_AK;
writeb(temp, &i2c_regs->i2cr);
/* write slave address */
ret = tx_byte(i2c_regs, chip << 1);
if (ret < 0)
return ret;
while (alen--) {
ret = tx_byte(i2c_regs, (addr >> (alen * 8)) & 0xff);
if (ret < 0)
return ret;
}
return 0;
}
static int i2c_idle_bus(void *base);
static int i2c_init_transfer(struct mxc_i2c_regs *i2c_regs,
uchar chip, uint addr, int alen)
{
int retry;
int ret;
for (retry = 0; retry < 3; retry++) {
ret = i2c_init_transfer_(i2c_regs, chip, addr, alen);
if (ret >= 0)
return 0;
i2c_imx_stop(i2c_regs);
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_regs->i2cr);
udelay(100);
if (i2c_idle_bus(i2c_regs) < 0)
break;
}
printf("%s: give up i2c_regs=%p\n", __func__, i2c_regs);
return ret;
}
/*
* Read data from I2C device
*/
int bus_i2c_read(void *base, uchar chip, uint addr, int alen, uchar *buf,
int len)
{
int ret;
unsigned int temp;
int i;
struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
ret = i2c_init_transfer(i2c_regs, chip, addr, alen);
if (ret < 0)
return ret;
temp = readb(&i2c_regs->i2cr);
temp |= I2CR_RSTA;
writeb(temp, &i2c_regs->i2cr);
ret = tx_byte(i2c_regs, (chip << 1) | 1);
if (ret < 0) {
i2c_imx_stop(i2c_regs);
return ret;
}
/* setup bus to read data */
temp = readb(&i2c_regs->i2cr);
temp &= ~(I2CR_MTX | I2CR_TX_NO_AK);
if (len == 1)
temp |= I2CR_TX_NO_AK;
writeb(temp, &i2c_regs->i2cr);
writeb(I2SR_IIF_CLEAR, &i2c_regs->i2sr);
readb(&i2c_regs->i2dr); /* dummy read to clear ICF */
/* read data */
for (i = 0; i < len; i++) {
ret = wait_for_sr_state(i2c_regs, ST_IIF);
if (ret < 0) {
i2c_imx_stop(i2c_regs);
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_regs);
} else if (i == (len - 2)) {
temp = readb(&i2c_regs->i2cr);
temp |= I2CR_TX_NO_AK;
writeb(temp, &i2c_regs->i2cr);
}
writeb(I2SR_IIF_CLEAR, &i2c_regs->i2sr);
buf[i] = readb(&i2c_regs->i2dr);
}
i2c_imx_stop(i2c_regs);
return 0;
}
/*
* Write data to I2C device
*/
int bus_i2c_write(void *base, uchar chip, uint addr, int alen,
const uchar *buf, int len)
{
int ret;
int i;
struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
ret = i2c_init_transfer(i2c_regs, chip, addr, alen);
if (ret < 0)
return ret;
for (i = 0; i < len; i++) {
ret = tx_byte(i2c_regs, buf[i]);
if (ret < 0)
break;
}
i2c_imx_stop(i2c_regs);
return ret;
}
struct i2c_parms {
void *base;
void *idle_bus_data;
int (*idle_bus_fn)(void *p);
};
struct sram_data {
unsigned curr_i2c_bus;
struct i2c_parms i2c_data[3];
};
/*
* For SPL boot some boards need i2c before SDRAM is initialized so force
* variables to live in SRAM
*/
static struct sram_data __attribute__((section(".data"))) srdata;
static void * const i2c_bases[] = {
#if defined(CONFIG_MX25)
(void *)IMX_I2C_BASE,
(void *)IMX_I2C2_BASE,
(void *)IMX_I2C3_BASE
#elif defined(CONFIG_MX27)
(void *)IMX_I2C1_BASE,
(void *)IMX_I2C2_BASE
#elif defined(CONFIG_MX31) || defined(CONFIG_MX35) || \
defined(CONFIG_MX51) || defined(CONFIG_MX53) || \
defined(CONFIG_MX6)
(void *)I2C1_BASE_ADDR,
(void *)I2C2_BASE_ADDR,
(void *)I2C3_BASE_ADDR
#elif defined(CONFIG_VF610)
(void *)I2C0_BASE_ADDR
#else
#error "architecture not supported"
#endif
};
void *i2c_get_base(struct i2c_adapter *adap)
{
return i2c_bases[adap->hwadapnr];
}
static struct i2c_parms *i2c_get_parms(void *base)
{
int i = 0;
struct i2c_parms *p = srdata.i2c_data;
while (i < ARRAY_SIZE(srdata.i2c_data)) {
if (p->base == base)
return p;
p++;
i++;
}
printf("Invalid I2C base: %p\n", base);
return NULL;
}
static int i2c_idle_bus(void *base)
{
struct i2c_parms *p = i2c_get_parms(base);
if (p && p->idle_bus_fn)
return p->idle_bus_fn(p->idle_bus_data);
return 0;
}
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(void *base, int speed, int unused,
int (*idle_bus_fn)(void *p), void *idle_bus_data)
{
int i = 0;
struct i2c_parms *p = srdata.i2c_data;
if (!base)
return;
for (;;) {
if (!p->base || (p->base == base)) {
p->base = base;
if (idle_bus_fn) {
p->idle_bus_fn = idle_bus_fn;
p->idle_bus_data = idle_bus_data;
}
break;
}
p++;
i++;
if (i >= ARRAY_SIZE(srdata.i2c_data))
return;
}
bus_i2c_set_bus_speed(base, speed);
}
/*
* Init I2C Bus
*/
static void mxc_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
{
bus_i2c_init(i2c_get_base(adap), speed, slaveaddr, NULL, NULL);
}
/*
* Set I2C Speed
*/
static uint 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
*/
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)
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)
#if defined(CONFIG_MX31) || defined(CONFIG_MX35) ||\
defined(CONFIG_MX51) || defined(CONFIG_MX53) ||\
defined(CONFIG_MX6)
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
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