rockchip: Add I2C driver

Add an I2C driver for the Rockchip RK3288, using driver model. It should work
for other Rockchip SoCs also.

Signed-off-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Simon Glass 2015-08-30 16:55:39 -06:00
parent 2444dae587
commit 3437469985
4 changed files with 471 additions and 0 deletions

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@ -0,0 +1,70 @@
/*
* (C) Copyright 2012 SAMSUNG Electronics
* Jaehoon Chung <jh80.chung@samsung.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef __ASM_ARCH_I2C_H
#define __ASM_ARCH_I2C_H
struct i2c_regs {
u32 con;
u32 clkdiv;
u32 mrxaddr;
u32 mrxraddr;
u32 mtxcnt;
u32 mrxcnt;
u32 ien;
u32 ipd;
u32 fcnt;
u32 reserved0[0x37];
u32 txdata[8];
u32 reserved1[0x38];
u32 rxdata[8];
};
/* Control register */
#define I2C_CON_EN (1 << 0)
#define I2C_CON_MOD(mod) ((mod) << 1)
#define I2C_MODE_TX 0x00
#define I2C_MODE_TRX 0x01
#define I2C_MODE_RX 0x02
#define I2C_MODE_RRX 0x03
#define I2C_CON_MASK (3 << 1)
#define I2C_CON_START (1 << 3)
#define I2C_CON_STOP (1 << 4)
#define I2C_CON_LASTACK (1 << 5)
#define I2C_CON_ACTACK (1 << 6)
/* Clock dividor register */
#define I2C_CLKDIV_VAL(divl, divh) \
(((divl) & 0xffff) | (((divh) << 16) & 0xffff0000))
/* the slave address accessed for master rx mode */
#define I2C_MRXADDR_SET(vld, addr) (((vld) << 24) | (addr))
/* the slave register address accessed for master rx mode */
#define I2C_MRXRADDR_SET(vld, raddr) (((vld) << 24) | (raddr))
/* interrupt enable register */
#define I2C_BTFIEN (1 << 0)
#define I2C_BRFIEN (1 << 1)
#define I2C_MBTFIEN (1 << 2)
#define I2C_MBRFIEN (1 << 3)
#define I2C_STARTIEN (1 << 4)
#define I2C_STOPIEN (1 << 5)
#define I2C_NAKRCVIEN (1 << 6)
/* interrupt pending register */
#define I2C_BTFIPD (1 << 0)
#define I2C_BRFIPD (1 << 1)
#define I2C_MBTFIPD (1 << 2)
#define I2C_MBRFIPD (1 << 3)
#define I2C_STARTIPD (1 << 4)
#define I2C_STOPIPD (1 << 5)
#define I2C_NAKRCVIPD (1 << 6)
#define I2C_IPD_ALL_CLEAN 0x7f
#endif

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@ -58,6 +58,15 @@ config DM_I2C_GPIO
bindings are supported.
Binding info: doc/device-tree-bindings/i2c/i2c-gpio.txt
config SYS_I2C_ROCKCHIP
bool "Rockchip I2C driver"
depends on DM_I2C
help
Add support for the Rockchip I2C driver. This is used with various
Rockchip parts such as RK3126, RK3128, RK3036 and RK3288. All chips
have several I2C ports and all are provided, controled by the
device tree.
config SYS_I2C_SANDBOX
bool "Sandbox I2C driver"
depends on SANDBOX && DM_I2C

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@ -31,6 +31,7 @@ obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
obj-$(CONFIG_SYS_I2C_OMAP34XX) += omap24xx_i2c.o
obj-$(CONFIG_SYS_I2C_PPC4XX) += ppc4xx_i2c.o
obj-$(CONFIG_SYS_I2C_RCAR) += rcar_i2c.o
obj-$(CONFIG_SYS_I2C_ROCKCHIP) += rk_i2c.o
obj-$(CONFIG_SYS_I2C_S3C24X0) += s3c24x0_i2c.o
obj-$(CONFIG_SYS_I2C_SANDBOX) += sandbox_i2c.o i2c-emul-uclass.o
obj-$(CONFIG_SYS_I2C_SH) += sh_i2c.o

391
drivers/i2c/rk_i2c.c Normal file
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@ -0,0 +1,391 @@
/*
* (C) Copyright 2015 Google, Inc
*
* (C) Copyright 2008-2014 Rockchip Electronics
* Peter, Software Engineering, <superpeter.cai@gmail.com>.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <clk.h>
#include <dm.h>
#include <errno.h>
#include <i2c.h>
#include <asm/io.h>
#include <asm/arch/clock.h>
#include <asm/arch/i2c.h>
#include <asm/arch/periph.h>
#include <dm/pinctrl.h>
#include <linux/sizes.h>
DECLARE_GLOBAL_DATA_PTR;
/* i2c timerout */
#define I2C_TIMEOUT_MS 100
#define I2C_RETRY_COUNT 3
/* rk i2c fifo max transfer bytes */
#define RK_I2C_FIFO_SIZE 32
struct rk_i2c {
struct udevice *clk;
struct udevice *pinctrl;
struct i2c_regs *regs;
unsigned int speed;
enum periph_id id;
};
static inline void rk_i2c_get_div(int div, int *divh, int *divl)
{
*divl = div / 2;
if (div % 2 == 0)
*divh = div / 2;
else
*divh = DIV_ROUND_UP(div, 2);
}
/*
* SCL Divisor = 8 * (CLKDIVL+1 + CLKDIVH+1)
* SCL = PCLK / SCLK Divisor
* i2c_rate = PCLK
*/
static void rk_i2c_set_clk(struct rk_i2c *i2c, uint32_t scl_rate)
{
uint32_t i2c_rate;
int div, divl, divh;
/* First get i2c rate from pclk */
i2c_rate = clk_get_periph_rate(i2c->clk, i2c->id);
div = DIV_ROUND_UP(i2c_rate, scl_rate * 8) - 2;
divh = 0;
divl = 0;
if (div >= 0)
rk_i2c_get_div(div, &divh, &divl);
writel(I2C_CLKDIV_VAL(divl, divh), &i2c->regs->clkdiv);
debug("rk_i2c_set_clk: i2c rate = %d, scl rate = %d\n", i2c_rate,
scl_rate);
debug("set i2c clk div = %d, divh = %d, divl = %d\n", div, divh, divl);
debug("set clk(I2C_CLKDIV: 0x%08x)\n", readl(&i2c->regs->clkdiv));
}
static void rk_i2c_show_regs(struct i2c_regs *regs)
{
#ifdef DEBUG
uint i;
debug("i2c_con: 0x%08x\n", readl(&regs->con));
debug("i2c_clkdiv: 0x%08x\n", readl(&regs->clkdiv));
debug("i2c_mrxaddr: 0x%08x\n", readl(&regs->mrxaddr));
debug("i2c_mrxraddR: 0x%08x\n", readl(&regs->mrxraddr));
debug("i2c_mtxcnt: 0x%08x\n", readl(&regs->mtxcnt));
debug("i2c_mrxcnt: 0x%08x\n", readl(&regs->mrxcnt));
debug("i2c_ien: 0x%08x\n", readl(&regs->ien));
debug("i2c_ipd: 0x%08x\n", readl(&regs->ipd));
debug("i2c_fcnt: 0x%08x\n", readl(&regs->fcnt));
for (i = 0; i < 8; i++)
debug("i2c_txdata%d: 0x%08x\n", i, readl(&regs->txdata[i]));
for (i = 0; i < 8; i++)
debug("i2c_rxdata%d: 0x%08x\n", i, readl(&regs->rxdata[i]));
#endif
}
static int rk_i2c_send_start_bit(struct rk_i2c *i2c)
{
struct i2c_regs *regs = i2c->regs;
ulong start;
debug("I2c Send Start bit.\n");
writel(I2C_IPD_ALL_CLEAN, &regs->ipd);
writel(I2C_CON_EN | I2C_CON_START, &regs->con);
writel(I2C_STARTIEN, &regs->ien);
start = get_timer(0);
while (1) {
if (readl(&regs->ipd) & I2C_STARTIPD) {
writel(I2C_STARTIPD, &regs->ipd);
break;
}
if (get_timer(start) > I2C_TIMEOUT_MS) {
debug("I2C Send Start Bit Timeout\n");
rk_i2c_show_regs(regs);
return -ETIMEDOUT;
}
udelay(1);
}
return 0;
}
static int rk_i2c_send_stop_bit(struct rk_i2c *i2c)
{
struct i2c_regs *regs = i2c->regs;
ulong start;
debug("I2c Send Stop bit.\n");
writel(I2C_IPD_ALL_CLEAN, &regs->ipd);
writel(I2C_CON_EN | I2C_CON_STOP, &regs->con);
writel(I2C_CON_STOP, &regs->ien);
start = get_timer(0);
while (1) {
if (readl(&regs->ipd) & I2C_STOPIPD) {
writel(I2C_STOPIPD, &regs->ipd);
break;
}
if (get_timer(start) > I2C_TIMEOUT_MS) {
debug("I2C Send Start Bit Timeout\n");
rk_i2c_show_regs(regs);
return -ETIMEDOUT;
}
udelay(1);
}
return 0;
}
static inline void rk_i2c_disable(struct rk_i2c *i2c)
{
writel(0, &i2c->regs->con);
}
static int rk_i2c_read(struct rk_i2c *i2c, uchar chip, uint reg, uint r_len,
uchar *buf, uint b_len)
{
struct i2c_regs *regs = i2c->regs;
uchar *pbuf = buf;
uint bytes_remain_len = b_len;
uint bytes_xferred = 0;
uint words_xferred = 0;
ulong start;
uint con = 0;
uint rxdata;
uint i, j;
int err;
debug("rk_i2c_read: chip = %d, reg = %d, r_len = %d, b_len = %d\n",
chip, reg, r_len, b_len);
err = rk_i2c_send_start_bit(i2c);
if (err)
return err;
writel(I2C_MRXADDR_SET(1, chip << 1 | 1), &regs->mrxaddr);
if (r_len == 0) {
writel(0, &regs->mrxraddr);
} else if (r_len < 4) {
writel(I2C_MRXRADDR_SET(r_len, reg), &regs->mrxraddr);
} else {
debug("I2C Read: addr len %d not supported\n", r_len);
return -EIO;
}
while (bytes_remain_len) {
if (bytes_remain_len > RK_I2C_FIFO_SIZE) {
con = I2C_CON_EN | I2C_CON_MOD(I2C_MODE_TRX);
bytes_xferred = 32;
} else {
con = I2C_CON_EN | I2C_CON_MOD(I2C_MODE_TRX) |
I2C_CON_LASTACK;
bytes_xferred = bytes_remain_len;
}
words_xferred = DIV_ROUND_UP(bytes_xferred, 4);
writel(con, &regs->con);
writel(bytes_xferred, &regs->mrxcnt);
writel(I2C_MBRFIEN | I2C_NAKRCVIEN, &regs->ien);
start = get_timer(0);
while (1) {
if (readl(&regs->ipd) & I2C_NAKRCVIPD) {
writel(I2C_NAKRCVIPD, &regs->ipd);
err = -EREMOTEIO;
}
if (readl(&regs->ipd) & I2C_MBRFIPD) {
writel(I2C_MBRFIPD, &regs->ipd);
break;
}
if (get_timer(start) > I2C_TIMEOUT_MS) {
debug("I2C Read Data Timeout\n");
err = -ETIMEDOUT;
rk_i2c_show_regs(regs);
goto i2c_exit;
}
udelay(1);
}
for (i = 0; i < words_xferred; i++) {
rxdata = readl(&regs->rxdata[i]);
debug("I2c Read RXDATA[%d] = 0x%x\n", i, rxdata);
for (j = 0; j < 4; j++) {
if ((i * 4 + j) == bytes_xferred)
break;
*pbuf++ = (rxdata >> (j * 8)) & 0xff;
}
}
bytes_remain_len -= bytes_xferred;
debug("I2C Read bytes_remain_len %d\n", bytes_remain_len);
}
i2c_exit:
rk_i2c_send_stop_bit(i2c);
rk_i2c_disable(i2c);
return err;
}
static int rk_i2c_write(struct rk_i2c *i2c, uchar chip, uint reg, uint r_len,
uchar *buf, uint b_len)
{
struct i2c_regs *regs = i2c->regs;
int err;
uchar *pbuf = buf;
uint bytes_remain_len = b_len + r_len + 1;
uint bytes_xferred = 0;
uint words_xferred = 0;
ulong start;
uint txdata;
uint i, j;
debug("rk_i2c_write: chip = %d, reg = %d, r_len = %d, b_len = %d\n",
chip, reg, r_len, b_len);
err = rk_i2c_send_start_bit(i2c);
if (err)
return err;
while (bytes_remain_len) {
if (bytes_remain_len > RK_I2C_FIFO_SIZE)
bytes_xferred = 32;
else
bytes_xferred = bytes_remain_len;
words_xferred = DIV_ROUND_UP(bytes_xferred, 4);
for (i = 0; i < words_xferred; i++) {
txdata = 0;
for (j = 0; j < 4; j++) {
if ((i * 4 + j) == bytes_xferred)
break;
if (i == 0 && j == 0) {
txdata |= (chip << 1);
} else if (i == 0 && j <= r_len) {
txdata |= (reg &
(0xff << ((j - 1) * 8))) << 8;
} else {
txdata |= (*pbuf++)<<(j * 8);
}
writel(txdata, &regs->txdata[i]);
}
debug("I2c Write TXDATA[%d] = 0x%x\n", i, txdata);
}
writel(I2C_CON_EN | I2C_CON_MOD(I2C_MODE_TX), &regs->con);
writel(bytes_xferred, &regs->mtxcnt);
writel(I2C_MBTFIEN | I2C_NAKRCVIEN, &regs->ien);
start = get_timer(0);
while (1) {
if (readl(&regs->ipd) & I2C_NAKRCVIPD) {
writel(I2C_NAKRCVIPD, &regs->ipd);
err = -EREMOTEIO;
}
if (readl(&regs->ipd) & I2C_MBTFIPD) {
writel(I2C_MBTFIPD, &regs->ipd);
break;
}
if (get_timer(start) > I2C_TIMEOUT_MS) {
debug("I2C Write Data Timeout\n");
err = -ETIMEDOUT;
rk_i2c_show_regs(regs);
goto i2c_exit;
}
udelay(1);
}
bytes_remain_len -= bytes_xferred;
debug("I2C Write bytes_remain_len %d\n", bytes_remain_len);
}
i2c_exit:
rk_i2c_send_stop_bit(i2c);
rk_i2c_disable(i2c);
return err;
}
static int rockchip_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
int nmsgs)
{
struct rk_i2c *i2c = dev_get_priv(bus);
int ret;
debug("i2c_xfer: %d messages\n", nmsgs);
for (; nmsgs > 0; nmsgs--, msg++) {
debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
if (msg->flags & I2C_M_RD) {
ret = rk_i2c_read(i2c, msg->addr, 0, 0, msg->buf,
msg->len);
} else {
ret = rk_i2c_write(i2c, msg->addr, 0, 0, msg->buf,
msg->len);
}
if (ret) {
debug("i2c_write: error sending\n");
return -EREMOTEIO;
}
}
return 0;
}
int rockchip_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
{
struct rk_i2c *i2c = dev_get_priv(bus);
rk_i2c_set_clk(i2c, speed);
return 0;
}
static int rockchip_i2c_probe(struct udevice *bus)
{
struct rk_i2c *i2c = dev_get_priv(bus);
int ret;
ret = uclass_get_device(UCLASS_PINCTRL, 0, &i2c->pinctrl);
if (ret)
return ret;
ret = uclass_get_device(UCLASS_CLK, 0, &i2c->clk);
if (ret)
return ret;
ret = pinctrl_get_periph_id(i2c->pinctrl, bus);
if (ret < 0)
return ret;
i2c->id = ret;
i2c->regs = (void *)dev_get_addr(bus);
return pinctrl_request(i2c->pinctrl, i2c->id, 0);
}
static const struct dm_i2c_ops rockchip_i2c_ops = {
.xfer = rockchip_i2c_xfer,
.set_bus_speed = rockchip_i2c_set_bus_speed,
};
static const struct udevice_id rockchip_i2c_ids[] = {
{ .compatible = "rockchip,rk3288-i2c" },
{ }
};
U_BOOT_DRIVER(i2c_rockchip) = {
.name = "i2c_rockchip",
.id = UCLASS_I2C,
.of_match = rockchip_i2c_ids,
.probe = rockchip_i2c_probe,
.priv_auto_alloc_size = sizeof(struct rk_i2c),
.ops = &rockchip_i2c_ops,
};