OpenCloudOS-Kernel/drivers/i2c/busses/i2c-mt65xx.c

1462 lines
38 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2014 MediaTek Inc.
* Author: Xudong Chen <xudong.chen@mediatek.com>
*/
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/scatterlist.h>
#include <linux/sched.h>
#include <linux/slab.h>
#define I2C_RS_TRANSFER (1 << 4)
#define I2C_ARB_LOST (1 << 3)
#define I2C_HS_NACKERR (1 << 2)
#define I2C_ACKERR (1 << 1)
#define I2C_TRANSAC_COMP (1 << 0)
#define I2C_TRANSAC_START (1 << 0)
#define I2C_RS_MUL_CNFG (1 << 15)
#define I2C_RS_MUL_TRIG (1 << 14)
#define I2C_DCM_DISABLE 0x0000
#define I2C_IO_CONFIG_OPEN_DRAIN 0x0003
#define I2C_IO_CONFIG_PUSH_PULL 0x0000
#define I2C_SOFT_RST 0x0001
#define I2C_HANDSHAKE_RST 0x0020
#define I2C_FIFO_ADDR_CLR 0x0001
#define I2C_DELAY_LEN 0x0002
#define I2C_ST_START_CON 0x8001
#define I2C_FS_START_CON 0x1800
#define I2C_TIME_CLR_VALUE 0x0000
#define I2C_TIME_DEFAULT_VALUE 0x0003
#define I2C_WRRD_TRANAC_VALUE 0x0002
#define I2C_RD_TRANAC_VALUE 0x0001
#define I2C_SCL_MIS_COMP_VALUE 0x0000
#define I2C_CHN_CLR_FLAG 0x0000
#define I2C_RELIABILITY 0x0010
#define I2C_DMAACK_ENABLE 0x0008
#define I2C_DMA_CON_TX 0x0000
#define I2C_DMA_CON_RX 0x0001
#define I2C_DMA_ASYNC_MODE 0x0004
#define I2C_DMA_SKIP_CONFIG 0x0010
#define I2C_DMA_DIR_CHANGE 0x0200
#define I2C_DMA_START_EN 0x0001
#define I2C_DMA_INT_FLAG_NONE 0x0000
#define I2C_DMA_CLR_FLAG 0x0000
#define I2C_DMA_WARM_RST 0x0001
#define I2C_DMA_HARD_RST 0x0002
#define I2C_DMA_HANDSHAKE_RST 0x0004
#define MAX_SAMPLE_CNT_DIV 8
#define MAX_STEP_CNT_DIV 64
#define MAX_CLOCK_DIV 256
#define MAX_HS_STEP_CNT_DIV 8
#define I2C_STANDARD_MODE_BUFFER (1000 / 2)
#define I2C_FAST_MODE_BUFFER (300 / 2)
#define I2C_FAST_MODE_PLUS_BUFFER (20 / 2)
#define I2C_CONTROL_RS (0x1 << 1)
#define I2C_CONTROL_DMA_EN (0x1 << 2)
#define I2C_CONTROL_CLK_EXT_EN (0x1 << 3)
#define I2C_CONTROL_DIR_CHANGE (0x1 << 4)
#define I2C_CONTROL_ACKERR_DET_EN (0x1 << 5)
#define I2C_CONTROL_TRANSFER_LEN_CHANGE (0x1 << 6)
#define I2C_CONTROL_DMAACK_EN (0x1 << 8)
#define I2C_CONTROL_ASYNC_MODE (0x1 << 9)
#define I2C_CONTROL_WRAPPER (0x1 << 0)
#define I2C_DRV_NAME "i2c-mt65xx"
enum DMA_REGS_OFFSET {
OFFSET_INT_FLAG = 0x0,
OFFSET_INT_EN = 0x04,
OFFSET_EN = 0x08,
OFFSET_RST = 0x0c,
OFFSET_CON = 0x18,
OFFSET_TX_MEM_ADDR = 0x1c,
OFFSET_RX_MEM_ADDR = 0x20,
OFFSET_TX_LEN = 0x24,
OFFSET_RX_LEN = 0x28,
OFFSET_TX_4G_MODE = 0x54,
OFFSET_RX_4G_MODE = 0x58,
};
enum i2c_trans_st_rs {
I2C_TRANS_STOP = 0,
I2C_TRANS_REPEATED_START,
};
enum mtk_trans_op {
I2C_MASTER_WR = 1,
I2C_MASTER_RD,
I2C_MASTER_WRRD,
};
enum I2C_REGS_OFFSET {
OFFSET_DATA_PORT,
OFFSET_SLAVE_ADDR,
OFFSET_INTR_MASK,
OFFSET_INTR_STAT,
OFFSET_CONTROL,
OFFSET_TRANSFER_LEN,
OFFSET_TRANSAC_LEN,
OFFSET_DELAY_LEN,
OFFSET_TIMING,
OFFSET_START,
OFFSET_EXT_CONF,
OFFSET_FIFO_STAT,
OFFSET_FIFO_THRESH,
OFFSET_FIFO_ADDR_CLR,
OFFSET_IO_CONFIG,
OFFSET_RSV_DEBUG,
OFFSET_HS,
OFFSET_SOFTRESET,
OFFSET_DCM_EN,
OFFSET_MULTI_DMA,
OFFSET_PATH_DIR,
OFFSET_DEBUGSTAT,
OFFSET_DEBUGCTRL,
OFFSET_TRANSFER_LEN_AUX,
OFFSET_CLOCK_DIV,
OFFSET_LTIMING,
OFFSET_SCL_HIGH_LOW_RATIO,
OFFSET_HS_SCL_HIGH_LOW_RATIO,
OFFSET_SCL_MIS_COMP_POINT,
OFFSET_STA_STO_AC_TIMING,
OFFSET_HS_STA_STO_AC_TIMING,
OFFSET_SDA_TIMING,
};
static const u16 mt_i2c_regs_v1[] = {
[OFFSET_DATA_PORT] = 0x0,
[OFFSET_SLAVE_ADDR] = 0x4,
[OFFSET_INTR_MASK] = 0x8,
[OFFSET_INTR_STAT] = 0xc,
[OFFSET_CONTROL] = 0x10,
[OFFSET_TRANSFER_LEN] = 0x14,
[OFFSET_TRANSAC_LEN] = 0x18,
[OFFSET_DELAY_LEN] = 0x1c,
[OFFSET_TIMING] = 0x20,
[OFFSET_START] = 0x24,
[OFFSET_EXT_CONF] = 0x28,
[OFFSET_FIFO_STAT] = 0x30,
[OFFSET_FIFO_THRESH] = 0x34,
[OFFSET_FIFO_ADDR_CLR] = 0x38,
[OFFSET_IO_CONFIG] = 0x40,
[OFFSET_RSV_DEBUG] = 0x44,
[OFFSET_HS] = 0x48,
[OFFSET_SOFTRESET] = 0x50,
[OFFSET_DCM_EN] = 0x54,
[OFFSET_PATH_DIR] = 0x60,
[OFFSET_DEBUGSTAT] = 0x64,
[OFFSET_DEBUGCTRL] = 0x68,
[OFFSET_TRANSFER_LEN_AUX] = 0x6c,
[OFFSET_CLOCK_DIV] = 0x70,
[OFFSET_SCL_HIGH_LOW_RATIO] = 0x74,
[OFFSET_HS_SCL_HIGH_LOW_RATIO] = 0x78,
[OFFSET_SCL_MIS_COMP_POINT] = 0x7C,
[OFFSET_STA_STO_AC_TIMING] = 0x80,
[OFFSET_HS_STA_STO_AC_TIMING] = 0x84,
[OFFSET_SDA_TIMING] = 0x88,
};
static const u16 mt_i2c_regs_v2[] = {
[OFFSET_DATA_PORT] = 0x0,
[OFFSET_SLAVE_ADDR] = 0x4,
[OFFSET_INTR_MASK] = 0x8,
[OFFSET_INTR_STAT] = 0xc,
[OFFSET_CONTROL] = 0x10,
[OFFSET_TRANSFER_LEN] = 0x14,
[OFFSET_TRANSAC_LEN] = 0x18,
[OFFSET_DELAY_LEN] = 0x1c,
[OFFSET_TIMING] = 0x20,
[OFFSET_START] = 0x24,
[OFFSET_EXT_CONF] = 0x28,
[OFFSET_LTIMING] = 0x2c,
[OFFSET_HS] = 0x30,
[OFFSET_IO_CONFIG] = 0x34,
[OFFSET_FIFO_ADDR_CLR] = 0x38,
[OFFSET_SDA_TIMING] = 0x3c,
[OFFSET_TRANSFER_LEN_AUX] = 0x44,
[OFFSET_CLOCK_DIV] = 0x48,
[OFFSET_SOFTRESET] = 0x50,
[OFFSET_MULTI_DMA] = 0x8c,
[OFFSET_SCL_MIS_COMP_POINT] = 0x90,
[OFFSET_DEBUGSTAT] = 0xe4,
[OFFSET_DEBUGCTRL] = 0xe8,
[OFFSET_FIFO_STAT] = 0xf4,
[OFFSET_FIFO_THRESH] = 0xf8,
[OFFSET_DCM_EN] = 0xf88,
};
struct mtk_i2c_compatible {
const struct i2c_adapter_quirks *quirks;
const u16 *regs;
unsigned char pmic_i2c: 1;
unsigned char dcm: 1;
unsigned char auto_restart: 1;
unsigned char aux_len_reg: 1;
unsigned char timing_adjust: 1;
unsigned char dma_sync: 1;
unsigned char ltiming_adjust: 1;
unsigned char apdma_sync: 1;
unsigned char max_dma_support;
};
struct mtk_i2c_ac_timing {
u16 htiming;
u16 ltiming;
u16 hs;
u16 ext;
u16 inter_clk_div;
u16 scl_hl_ratio;
u16 hs_scl_hl_ratio;
u16 sta_stop;
u16 hs_sta_stop;
u16 sda_timing;
};
struct mtk_i2c {
struct i2c_adapter adap; /* i2c host adapter */
struct device *dev;
struct completion msg_complete;
struct i2c_timings timing_info;
/* set in i2c probe */
void __iomem *base; /* i2c base addr */
void __iomem *pdmabase; /* dma base address*/
struct clk *clk_main; /* main clock for i2c bus */
struct clk *clk_dma; /* DMA clock for i2c via DMA */
struct clk *clk_pmic; /* PMIC clock for i2c from PMIC */
struct clk *clk_arb; /* Arbitrator clock for i2c */
bool have_pmic; /* can use i2c pins from PMIC */
bool use_push_pull; /* IO config push-pull mode */
u16 irq_stat; /* interrupt status */
unsigned int clk_src_div;
unsigned int speed_hz; /* The speed in transfer */
enum mtk_trans_op op;
u16 timing_reg;
u16 high_speed_reg;
u16 ltiming_reg;
unsigned char auto_restart;
bool ignore_restart_irq;
struct mtk_i2c_ac_timing ac_timing;
const struct mtk_i2c_compatible *dev_comp;
};
/**
* struct i2c_spec_values:
* @min_low_ns: min LOW period of the SCL clock
* @min_su_sta_ns: min set-up time for a repeated START condition
* @max_hd_dat_ns: max data hold time
* @min_su_dat_ns: min data set-up time
*/
struct i2c_spec_values {
unsigned int min_low_ns;
unsigned int min_su_sta_ns;
unsigned int max_hd_dat_ns;
unsigned int min_su_dat_ns;
};
static const struct i2c_spec_values standard_mode_spec = {
.min_low_ns = 4700 + I2C_STANDARD_MODE_BUFFER,
.min_su_sta_ns = 4700 + I2C_STANDARD_MODE_BUFFER,
.max_hd_dat_ns = 3450 - I2C_STANDARD_MODE_BUFFER,
.min_su_dat_ns = 250 + I2C_STANDARD_MODE_BUFFER,
};
static const struct i2c_spec_values fast_mode_spec = {
.min_low_ns = 1300 + I2C_FAST_MODE_BUFFER,
.min_su_sta_ns = 600 + I2C_FAST_MODE_BUFFER,
.max_hd_dat_ns = 900 - I2C_FAST_MODE_BUFFER,
.min_su_dat_ns = 100 + I2C_FAST_MODE_BUFFER,
};
static const struct i2c_spec_values fast_mode_plus_spec = {
.min_low_ns = 500 + I2C_FAST_MODE_PLUS_BUFFER,
.min_su_sta_ns = 260 + I2C_FAST_MODE_PLUS_BUFFER,
.max_hd_dat_ns = 400 - I2C_FAST_MODE_PLUS_BUFFER,
.min_su_dat_ns = 50 + I2C_FAST_MODE_PLUS_BUFFER,
};
static const struct i2c_adapter_quirks mt6577_i2c_quirks = {
.flags = I2C_AQ_COMB_WRITE_THEN_READ,
.max_num_msgs = 1,
.max_write_len = 255,
.max_read_len = 255,
.max_comb_1st_msg_len = 255,
.max_comb_2nd_msg_len = 31,
};
static const struct i2c_adapter_quirks mt7622_i2c_quirks = {
.max_num_msgs = 255,
};
static const struct i2c_adapter_quirks mt8183_i2c_quirks = {
.flags = I2C_AQ_NO_ZERO_LEN,
};
static const struct mtk_i2c_compatible mt2712_compat = {
.regs = mt_i2c_regs_v1,
.pmic_i2c = 0,
.dcm = 1,
.auto_restart = 1,
.aux_len_reg = 1,
.timing_adjust = 1,
.dma_sync = 0,
.ltiming_adjust = 0,
.apdma_sync = 0,
.max_dma_support = 33,
};
static const struct mtk_i2c_compatible mt6577_compat = {
.quirks = &mt6577_i2c_quirks,
.regs = mt_i2c_regs_v1,
.pmic_i2c = 0,
.dcm = 1,
.auto_restart = 0,
.aux_len_reg = 0,
.timing_adjust = 0,
.dma_sync = 0,
.ltiming_adjust = 0,
.apdma_sync = 0,
.max_dma_support = 32,
};
static const struct mtk_i2c_compatible mt6589_compat = {
.quirks = &mt6577_i2c_quirks,
.regs = mt_i2c_regs_v1,
.pmic_i2c = 1,
.dcm = 0,
.auto_restart = 0,
.aux_len_reg = 0,
.timing_adjust = 0,
.dma_sync = 0,
.ltiming_adjust = 0,
.apdma_sync = 0,
.max_dma_support = 32,
};
static const struct mtk_i2c_compatible mt7622_compat = {
.quirks = &mt7622_i2c_quirks,
.regs = mt_i2c_regs_v1,
.pmic_i2c = 0,
.dcm = 1,
.auto_restart = 1,
.aux_len_reg = 1,
.timing_adjust = 0,
.dma_sync = 0,
.ltiming_adjust = 0,
.apdma_sync = 0,
.max_dma_support = 32,
};
static const struct mtk_i2c_compatible mt8173_compat = {
.regs = mt_i2c_regs_v1,
.pmic_i2c = 0,
.dcm = 1,
.auto_restart = 1,
.aux_len_reg = 1,
.timing_adjust = 0,
.dma_sync = 0,
.ltiming_adjust = 0,
.apdma_sync = 0,
.max_dma_support = 33,
};
static const struct mtk_i2c_compatible mt8183_compat = {
.quirks = &mt8183_i2c_quirks,
.regs = mt_i2c_regs_v2,
.pmic_i2c = 0,
.dcm = 0,
.auto_restart = 1,
.aux_len_reg = 1,
.timing_adjust = 1,
.dma_sync = 1,
.ltiming_adjust = 1,
.apdma_sync = 0,
.max_dma_support = 33,
};
static const struct mtk_i2c_compatible mt8192_compat = {
.quirks = &mt8183_i2c_quirks,
.regs = mt_i2c_regs_v2,
.pmic_i2c = 0,
.dcm = 0,
.auto_restart = 1,
.aux_len_reg = 1,
.timing_adjust = 1,
.dma_sync = 1,
.ltiming_adjust = 1,
.apdma_sync = 1,
.max_dma_support = 36,
};
static const struct of_device_id mtk_i2c_of_match[] = {
{ .compatible = "mediatek,mt2712-i2c", .data = &mt2712_compat },
{ .compatible = "mediatek,mt6577-i2c", .data = &mt6577_compat },
{ .compatible = "mediatek,mt6589-i2c", .data = &mt6589_compat },
{ .compatible = "mediatek,mt7622-i2c", .data = &mt7622_compat },
{ .compatible = "mediatek,mt8173-i2c", .data = &mt8173_compat },
{ .compatible = "mediatek,mt8183-i2c", .data = &mt8183_compat },
{ .compatible = "mediatek,mt8192-i2c", .data = &mt8192_compat },
{}
};
MODULE_DEVICE_TABLE(of, mtk_i2c_of_match);
static u16 mtk_i2c_readw(struct mtk_i2c *i2c, enum I2C_REGS_OFFSET reg)
{
return readw(i2c->base + i2c->dev_comp->regs[reg]);
}
static void mtk_i2c_writew(struct mtk_i2c *i2c, u16 val,
enum I2C_REGS_OFFSET reg)
{
writew(val, i2c->base + i2c->dev_comp->regs[reg]);
}
static int mtk_i2c_clock_enable(struct mtk_i2c *i2c)
{
int ret;
ret = clk_prepare_enable(i2c->clk_dma);
if (ret)
return ret;
ret = clk_prepare_enable(i2c->clk_main);
if (ret)
goto err_main;
if (i2c->have_pmic) {
ret = clk_prepare_enable(i2c->clk_pmic);
if (ret)
goto err_pmic;
}
if (i2c->clk_arb) {
ret = clk_prepare_enable(i2c->clk_arb);
if (ret)
goto err_arb;
}
return 0;
err_arb:
if (i2c->have_pmic)
clk_disable_unprepare(i2c->clk_pmic);
err_pmic:
clk_disable_unprepare(i2c->clk_main);
err_main:
clk_disable_unprepare(i2c->clk_dma);
return ret;
}
static void mtk_i2c_clock_disable(struct mtk_i2c *i2c)
{
if (i2c->clk_arb)
clk_disable_unprepare(i2c->clk_arb);
if (i2c->have_pmic)
clk_disable_unprepare(i2c->clk_pmic);
clk_disable_unprepare(i2c->clk_main);
clk_disable_unprepare(i2c->clk_dma);
}
static void mtk_i2c_init_hw(struct mtk_i2c *i2c)
{
u16 control_reg;
u16 intr_stat_reg;
u16 ext_conf_val;
mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_START);
intr_stat_reg = mtk_i2c_readw(i2c, OFFSET_INTR_STAT);
mtk_i2c_writew(i2c, intr_stat_reg, OFFSET_INTR_STAT);
if (i2c->dev_comp->apdma_sync) {
writel(I2C_DMA_WARM_RST, i2c->pdmabase + OFFSET_RST);
udelay(10);
writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
udelay(10);
writel(I2C_DMA_HANDSHAKE_RST | I2C_DMA_HARD_RST,
i2c->pdmabase + OFFSET_RST);
mtk_i2c_writew(i2c, I2C_HANDSHAKE_RST | I2C_SOFT_RST,
OFFSET_SOFTRESET);
udelay(10);
writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_SOFTRESET);
} else {
writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST);
udelay(50);
writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
mtk_i2c_writew(i2c, I2C_SOFT_RST, OFFSET_SOFTRESET);
}
/* Set ioconfig */
if (i2c->use_push_pull)
mtk_i2c_writew(i2c, I2C_IO_CONFIG_PUSH_PULL, OFFSET_IO_CONFIG);
else
mtk_i2c_writew(i2c, I2C_IO_CONFIG_OPEN_DRAIN, OFFSET_IO_CONFIG);
if (i2c->dev_comp->dcm)
mtk_i2c_writew(i2c, I2C_DCM_DISABLE, OFFSET_DCM_EN);
mtk_i2c_writew(i2c, i2c->timing_reg, OFFSET_TIMING);
mtk_i2c_writew(i2c, i2c->high_speed_reg, OFFSET_HS);
if (i2c->dev_comp->ltiming_adjust)
mtk_i2c_writew(i2c, i2c->ltiming_reg, OFFSET_LTIMING);
if (i2c->speed_hz <= I2C_MAX_STANDARD_MODE_FREQ)
ext_conf_val = I2C_ST_START_CON;
else
ext_conf_val = I2C_FS_START_CON;
if (i2c->dev_comp->timing_adjust) {
ext_conf_val = i2c->ac_timing.ext;
mtk_i2c_writew(i2c, i2c->ac_timing.inter_clk_div,
OFFSET_CLOCK_DIV);
mtk_i2c_writew(i2c, I2C_SCL_MIS_COMP_VALUE,
OFFSET_SCL_MIS_COMP_POINT);
mtk_i2c_writew(i2c, i2c->ac_timing.sda_timing,
OFFSET_SDA_TIMING);
if (i2c->dev_comp->ltiming_adjust) {
mtk_i2c_writew(i2c, i2c->ac_timing.htiming,
OFFSET_TIMING);
mtk_i2c_writew(i2c, i2c->ac_timing.hs, OFFSET_HS);
mtk_i2c_writew(i2c, i2c->ac_timing.ltiming,
OFFSET_LTIMING);
} else {
mtk_i2c_writew(i2c, i2c->ac_timing.scl_hl_ratio,
OFFSET_SCL_HIGH_LOW_RATIO);
mtk_i2c_writew(i2c, i2c->ac_timing.hs_scl_hl_ratio,
OFFSET_HS_SCL_HIGH_LOW_RATIO);
mtk_i2c_writew(i2c, i2c->ac_timing.sta_stop,
OFFSET_STA_STO_AC_TIMING);
mtk_i2c_writew(i2c, i2c->ac_timing.hs_sta_stop,
OFFSET_HS_STA_STO_AC_TIMING);
}
}
mtk_i2c_writew(i2c, ext_conf_val, OFFSET_EXT_CONF);
/* If use i2c pin from PMIC mt6397 side, need set PATH_DIR first */
if (i2c->have_pmic)
mtk_i2c_writew(i2c, I2C_CONTROL_WRAPPER, OFFSET_PATH_DIR);
control_reg = I2C_CONTROL_ACKERR_DET_EN |
I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN;
if (i2c->dev_comp->dma_sync)
control_reg |= I2C_CONTROL_DMAACK_EN | I2C_CONTROL_ASYNC_MODE;
mtk_i2c_writew(i2c, control_reg, OFFSET_CONTROL);
mtk_i2c_writew(i2c, I2C_DELAY_LEN, OFFSET_DELAY_LEN);
}
static const struct i2c_spec_values *mtk_i2c_get_spec(unsigned int speed)
{
if (speed <= I2C_MAX_STANDARD_MODE_FREQ)
return &standard_mode_spec;
else if (speed <= I2C_MAX_FAST_MODE_FREQ)
return &fast_mode_spec;
else
return &fast_mode_plus_spec;
}
static int mtk_i2c_max_step_cnt(unsigned int target_speed)
{
if (target_speed > I2C_MAX_FAST_MODE_PLUS_FREQ)
return MAX_HS_STEP_CNT_DIV;
else
return MAX_STEP_CNT_DIV;
}
/*
* Check and Calculate i2c ac-timing
*
* Hardware design:
* sample_ns = (1000000000 * (sample_cnt + 1)) / clk_src
* xxx_cnt_div = spec->min_xxx_ns / sample_ns
*
* Sample_ns is rounded down for xxx_cnt_div would be greater
* than the smallest spec.
* The sda_timing is chosen as the middle value between
* the largest and smallest.
*/
static int mtk_i2c_check_ac_timing(struct mtk_i2c *i2c,
unsigned int clk_src,
unsigned int check_speed,
unsigned int step_cnt,
unsigned int sample_cnt)
{
const struct i2c_spec_values *spec;
unsigned int su_sta_cnt, low_cnt, high_cnt, max_step_cnt;
unsigned int sda_max, sda_min, clk_ns, max_sta_cnt = 0x3f;
unsigned int sample_ns = div_u64(1000000000ULL * (sample_cnt + 1),
clk_src);
if (!i2c->dev_comp->timing_adjust)
return 0;
if (i2c->dev_comp->ltiming_adjust)
max_sta_cnt = 0x100;
spec = mtk_i2c_get_spec(check_speed);
if (i2c->dev_comp->ltiming_adjust)
clk_ns = 1000000000 / clk_src;
else
clk_ns = sample_ns / 2;
su_sta_cnt = DIV_ROUND_UP(spec->min_su_sta_ns +
i2c->timing_info.scl_int_delay_ns, clk_ns);
if (su_sta_cnt > max_sta_cnt)
return -1;
low_cnt = DIV_ROUND_UP(spec->min_low_ns, sample_ns);
max_step_cnt = mtk_i2c_max_step_cnt(check_speed);
if ((2 * step_cnt) > low_cnt && low_cnt < max_step_cnt) {
if (low_cnt > step_cnt) {
high_cnt = 2 * step_cnt - low_cnt;
} else {
high_cnt = step_cnt;
low_cnt = step_cnt;
}
} else {
return -2;
}
sda_max = spec->max_hd_dat_ns / sample_ns;
if (sda_max > low_cnt)
sda_max = 0;
sda_min = DIV_ROUND_UP(spec->min_su_dat_ns, sample_ns);
if (sda_min < low_cnt)
sda_min = 0;
if (sda_min > sda_max)
return -3;
if (check_speed > I2C_MAX_FAST_MODE_PLUS_FREQ) {
if (i2c->dev_comp->ltiming_adjust) {
i2c->ac_timing.hs = I2C_TIME_DEFAULT_VALUE |
(sample_cnt << 12) | (high_cnt << 8);
i2c->ac_timing.ltiming &= ~GENMASK(15, 9);
i2c->ac_timing.ltiming |= (sample_cnt << 12) |
(low_cnt << 9);
i2c->ac_timing.ext &= ~GENMASK(7, 1);
i2c->ac_timing.ext |= (su_sta_cnt << 1) | (1 << 0);
} else {
i2c->ac_timing.hs_scl_hl_ratio = (1 << 12) |
(high_cnt << 6) | low_cnt;
i2c->ac_timing.hs_sta_stop = (su_sta_cnt << 8) |
su_sta_cnt;
}
i2c->ac_timing.sda_timing &= ~GENMASK(11, 6);
i2c->ac_timing.sda_timing |= (1 << 12) |
((sda_max + sda_min) / 2) << 6;
} else {
if (i2c->dev_comp->ltiming_adjust) {
i2c->ac_timing.htiming = (sample_cnt << 8) | (high_cnt);
i2c->ac_timing.ltiming = (sample_cnt << 6) | (low_cnt);
i2c->ac_timing.ext = (su_sta_cnt << 8) | (1 << 0);
} else {
i2c->ac_timing.scl_hl_ratio = (1 << 12) |
(high_cnt << 6) | low_cnt;
i2c->ac_timing.sta_stop = (su_sta_cnt << 8) |
su_sta_cnt;
}
i2c->ac_timing.sda_timing = (1 << 12) |
(sda_max + sda_min) / 2;
}
return 0;
}
/*
* Calculate i2c port speed
*
* Hardware design:
* i2c_bus_freq = parent_clk / (clock_div * 2 * sample_cnt * step_cnt)
* clock_div: fixed in hardware, but may be various in different SoCs
*
* The calculation want to pick the highest bus frequency that is still
* less than or equal to i2c->speed_hz. The calculation try to get
* sample_cnt and step_cn
*/
static int mtk_i2c_calculate_speed(struct mtk_i2c *i2c, unsigned int clk_src,
unsigned int target_speed,
unsigned int *timing_step_cnt,
unsigned int *timing_sample_cnt)
{
unsigned int step_cnt;
unsigned int sample_cnt;
unsigned int max_step_cnt;
unsigned int base_sample_cnt = MAX_SAMPLE_CNT_DIV;
unsigned int base_step_cnt;
unsigned int opt_div;
unsigned int best_mul;
unsigned int cnt_mul;
int ret = -EINVAL;
if (target_speed > I2C_MAX_HIGH_SPEED_MODE_FREQ)
target_speed = I2C_MAX_HIGH_SPEED_MODE_FREQ;
max_step_cnt = mtk_i2c_max_step_cnt(target_speed);
base_step_cnt = max_step_cnt;
/* Find the best combination */
opt_div = DIV_ROUND_UP(clk_src >> 1, target_speed);
best_mul = MAX_SAMPLE_CNT_DIV * max_step_cnt;
/* Search for the best pair (sample_cnt, step_cnt) with
* 0 < sample_cnt < MAX_SAMPLE_CNT_DIV
* 0 < step_cnt < max_step_cnt
* sample_cnt * step_cnt >= opt_div
* optimizing for sample_cnt * step_cnt being minimal
*/
for (sample_cnt = 1; sample_cnt <= MAX_SAMPLE_CNT_DIV; sample_cnt++) {
step_cnt = DIV_ROUND_UP(opt_div, sample_cnt);
cnt_mul = step_cnt * sample_cnt;
if (step_cnt > max_step_cnt)
continue;
if (cnt_mul < best_mul) {
ret = mtk_i2c_check_ac_timing(i2c, clk_src,
target_speed, step_cnt - 1, sample_cnt - 1);
if (ret)
continue;
best_mul = cnt_mul;
base_sample_cnt = sample_cnt;
base_step_cnt = step_cnt;
if (best_mul == opt_div)
break;
}
}
if (ret)
return -EINVAL;
sample_cnt = base_sample_cnt;
step_cnt = base_step_cnt;
if ((clk_src / (2 * sample_cnt * step_cnt)) > target_speed) {
/* In this case, hardware can't support such
* low i2c_bus_freq
*/
dev_dbg(i2c->dev, "Unsupported speed (%uhz)\n", target_speed);
return -EINVAL;
}
*timing_step_cnt = step_cnt - 1;
*timing_sample_cnt = sample_cnt - 1;
return 0;
}
static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk)
{
unsigned int clk_src;
unsigned int step_cnt;
unsigned int sample_cnt;
unsigned int l_step_cnt;
unsigned int l_sample_cnt;
unsigned int target_speed;
unsigned int clk_div;
unsigned int max_clk_div;
int ret;
target_speed = i2c->speed_hz;
parent_clk /= i2c->clk_src_div;
if (i2c->dev_comp->timing_adjust)
max_clk_div = MAX_CLOCK_DIV;
else
max_clk_div = 1;
for (clk_div = 1; clk_div <= max_clk_div; clk_div++) {
clk_src = parent_clk / clk_div;
if (target_speed > I2C_MAX_FAST_MODE_PLUS_FREQ) {
/* Set master code speed register */
ret = mtk_i2c_calculate_speed(i2c, clk_src,
I2C_MAX_FAST_MODE_FREQ,
&l_step_cnt,
&l_sample_cnt);
if (ret < 0)
continue;
i2c->timing_reg = (l_sample_cnt << 8) | l_step_cnt;
/* Set the high speed mode register */
ret = mtk_i2c_calculate_speed(i2c, clk_src,
target_speed, &step_cnt,
&sample_cnt);
if (ret < 0)
continue;
i2c->high_speed_reg = I2C_TIME_DEFAULT_VALUE |
(sample_cnt << 12) | (step_cnt << 8);
if (i2c->dev_comp->ltiming_adjust)
i2c->ltiming_reg =
(l_sample_cnt << 6) | l_step_cnt |
(sample_cnt << 12) | (step_cnt << 9);
} else {
ret = mtk_i2c_calculate_speed(i2c, clk_src,
target_speed, &l_step_cnt,
&l_sample_cnt);
if (ret < 0)
continue;
i2c->timing_reg = (l_sample_cnt << 8) | l_step_cnt;
/* Disable the high speed transaction */
i2c->high_speed_reg = I2C_TIME_CLR_VALUE;
if (i2c->dev_comp->ltiming_adjust)
i2c->ltiming_reg =
(l_sample_cnt << 6) | l_step_cnt;
}
break;
}
i2c->ac_timing.inter_clk_div = clk_div - 1;
return 0;
}
static void i2c_dump_register(struct mtk_i2c *i2c)
{
dev_dbg(i2c->dev, "SLAVE_ADDR: 0x%x, INTR_MASK: 0x%x\n",
mtk_i2c_readw(i2c, OFFSET_SLAVE_ADDR),
mtk_i2c_readw(i2c, OFFSET_INTR_MASK));
dev_dbg(i2c->dev, "INTR_STAT: 0x%x, CONTROL: 0x%x\n",
mtk_i2c_readw(i2c, OFFSET_INTR_STAT),
mtk_i2c_readw(i2c, OFFSET_CONTROL));
dev_dbg(i2c->dev, "TRANSFER_LEN: 0x%x, TRANSAC_LEN: 0x%x\n",
mtk_i2c_readw(i2c, OFFSET_TRANSFER_LEN),
mtk_i2c_readw(i2c, OFFSET_TRANSAC_LEN));
dev_dbg(i2c->dev, "DELAY_LEN: 0x%x, HTIMING: 0x%x\n",
mtk_i2c_readw(i2c, OFFSET_DELAY_LEN),
mtk_i2c_readw(i2c, OFFSET_TIMING));
dev_dbg(i2c->dev, "START: 0x%x, EXT_CONF: 0x%x\n",
mtk_i2c_readw(i2c, OFFSET_START),
mtk_i2c_readw(i2c, OFFSET_EXT_CONF));
dev_dbg(i2c->dev, "HS: 0x%x, IO_CONFIG: 0x%x\n",
mtk_i2c_readw(i2c, OFFSET_HS),
mtk_i2c_readw(i2c, OFFSET_IO_CONFIG));
dev_dbg(i2c->dev, "DCM_EN: 0x%x, TRANSFER_LEN_AUX: 0x%x\n",
mtk_i2c_readw(i2c, OFFSET_DCM_EN),
mtk_i2c_readw(i2c, OFFSET_TRANSFER_LEN_AUX));
dev_dbg(i2c->dev, "CLOCK_DIV: 0x%x, FIFO_STAT: 0x%x\n",
mtk_i2c_readw(i2c, OFFSET_CLOCK_DIV),
mtk_i2c_readw(i2c, OFFSET_FIFO_STAT));
dev_dbg(i2c->dev, "DEBUGCTRL : 0x%x, DEBUGSTAT: 0x%x\n",
mtk_i2c_readw(i2c, OFFSET_DEBUGCTRL),
mtk_i2c_readw(i2c, OFFSET_DEBUGSTAT));
if (i2c->dev_comp->regs == mt_i2c_regs_v2) {
dev_dbg(i2c->dev, "LTIMING: 0x%x, MULTI_DMA: 0x%x\n",
mtk_i2c_readw(i2c, OFFSET_LTIMING),
mtk_i2c_readw(i2c, OFFSET_MULTI_DMA));
}
dev_dbg(i2c->dev, "\nDMA_INT_FLAG: 0x%x, DMA_INT_EN: 0x%x\n",
readl(i2c->pdmabase + OFFSET_INT_FLAG),
readl(i2c->pdmabase + OFFSET_INT_EN));
dev_dbg(i2c->dev, "DMA_EN: 0x%x, DMA_CON: 0x%x\n",
readl(i2c->pdmabase + OFFSET_EN),
readl(i2c->pdmabase + OFFSET_CON));
dev_dbg(i2c->dev, "DMA_TX_MEM_ADDR: 0x%x, DMA_RX_MEM_ADDR: 0x%x\n",
readl(i2c->pdmabase + OFFSET_TX_MEM_ADDR),
readl(i2c->pdmabase + OFFSET_RX_MEM_ADDR));
dev_dbg(i2c->dev, "DMA_TX_LEN: 0x%x, DMA_RX_LEN: 0x%x\n",
readl(i2c->pdmabase + OFFSET_TX_LEN),
readl(i2c->pdmabase + OFFSET_RX_LEN));
dev_dbg(i2c->dev, "DMA_TX_4G_MODE: 0x%x, DMA_RX_4G_MODE: 0x%x",
readl(i2c->pdmabase + OFFSET_TX_4G_MODE),
readl(i2c->pdmabase + OFFSET_RX_4G_MODE));
}
static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
int num, int left_num)
{
u16 addr_reg;
u16 start_reg;
u16 control_reg;
u16 restart_flag = 0;
u16 dma_sync = 0;
u32 reg_4g_mode;
u32 reg_dma_reset;
u8 *dma_rd_buf = NULL;
u8 *dma_wr_buf = NULL;
dma_addr_t rpaddr = 0;
dma_addr_t wpaddr = 0;
int ret;
i2c->irq_stat = 0;
if (i2c->auto_restart)
restart_flag = I2C_RS_TRANSFER;
reinit_completion(&i2c->msg_complete);
if (i2c->dev_comp->apdma_sync &&
i2c->op != I2C_MASTER_WRRD && num > 1) {
mtk_i2c_writew(i2c, 0x00, OFFSET_DEBUGCTRL);
writel(I2C_DMA_HANDSHAKE_RST | I2C_DMA_WARM_RST,
i2c->pdmabase + OFFSET_RST);
ret = readw_poll_timeout(i2c->pdmabase + OFFSET_RST,
reg_dma_reset,
!(reg_dma_reset & I2C_DMA_WARM_RST),
0, 100);
if (ret) {
dev_err(i2c->dev, "DMA warm reset timeout\n");
return -ETIMEDOUT;
}
writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
mtk_i2c_writew(i2c, I2C_HANDSHAKE_RST, OFFSET_SOFTRESET);
mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_SOFTRESET);
mtk_i2c_writew(i2c, I2C_RELIABILITY | I2C_DMAACK_ENABLE,
OFFSET_DEBUGCTRL);
}
control_reg = mtk_i2c_readw(i2c, OFFSET_CONTROL) &
~(I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS);
if ((i2c->speed_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) || (left_num >= 1))
control_reg |= I2C_CONTROL_RS;
if (i2c->op == I2C_MASTER_WRRD)
control_reg |= I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS;
mtk_i2c_writew(i2c, control_reg, OFFSET_CONTROL);
addr_reg = i2c_8bit_addr_from_msg(msgs);
mtk_i2c_writew(i2c, addr_reg, OFFSET_SLAVE_ADDR);
/* Clear interrupt status */
mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR |
I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_STAT);
mtk_i2c_writew(i2c, I2C_FIFO_ADDR_CLR, OFFSET_FIFO_ADDR_CLR);
/* Enable interrupt */
mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR |
I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_MASK);
/* Set transfer and transaction len */
if (i2c->op == I2C_MASTER_WRRD) {
if (i2c->dev_comp->aux_len_reg) {
mtk_i2c_writew(i2c, msgs->len, OFFSET_TRANSFER_LEN);
mtk_i2c_writew(i2c, (msgs + 1)->len,
OFFSET_TRANSFER_LEN_AUX);
} else {
mtk_i2c_writew(i2c, msgs->len | ((msgs + 1)->len) << 8,
OFFSET_TRANSFER_LEN);
}
mtk_i2c_writew(i2c, I2C_WRRD_TRANAC_VALUE, OFFSET_TRANSAC_LEN);
} else {
mtk_i2c_writew(i2c, msgs->len, OFFSET_TRANSFER_LEN);
mtk_i2c_writew(i2c, num, OFFSET_TRANSAC_LEN);
}
if (i2c->dev_comp->apdma_sync) {
dma_sync = I2C_DMA_SKIP_CONFIG | I2C_DMA_ASYNC_MODE;
if (i2c->op == I2C_MASTER_WRRD)
dma_sync |= I2C_DMA_DIR_CHANGE;
}
/* Prepare buffer data to start transfer */
if (i2c->op == I2C_MASTER_RD) {
writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG);
writel(I2C_DMA_CON_RX | dma_sync, i2c->pdmabase + OFFSET_CON);
dma_rd_buf = i2c_get_dma_safe_msg_buf(msgs, 1);
if (!dma_rd_buf)
return -ENOMEM;
rpaddr = dma_map_single(i2c->dev, dma_rd_buf,
msgs->len, DMA_FROM_DEVICE);
if (dma_mapping_error(i2c->dev, rpaddr)) {
i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, false);
return -ENOMEM;
}
if (i2c->dev_comp->max_dma_support > 32) {
reg_4g_mode = upper_32_bits(rpaddr);
writel(reg_4g_mode, i2c->pdmabase + OFFSET_RX_4G_MODE);
}
writel((u32)rpaddr, i2c->pdmabase + OFFSET_RX_MEM_ADDR);
writel(msgs->len, i2c->pdmabase + OFFSET_RX_LEN);
} else if (i2c->op == I2C_MASTER_WR) {
writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG);
writel(I2C_DMA_CON_TX | dma_sync, i2c->pdmabase + OFFSET_CON);
dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 1);
if (!dma_wr_buf)
return -ENOMEM;
wpaddr = dma_map_single(i2c->dev, dma_wr_buf,
msgs->len, DMA_TO_DEVICE);
if (dma_mapping_error(i2c->dev, wpaddr)) {
i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
return -ENOMEM;
}
if (i2c->dev_comp->max_dma_support > 32) {
reg_4g_mode = upper_32_bits(wpaddr);
writel(reg_4g_mode, i2c->pdmabase + OFFSET_TX_4G_MODE);
}
writel((u32)wpaddr, i2c->pdmabase + OFFSET_TX_MEM_ADDR);
writel(msgs->len, i2c->pdmabase + OFFSET_TX_LEN);
} else {
writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_INT_FLAG);
writel(I2C_DMA_CLR_FLAG | dma_sync, i2c->pdmabase + OFFSET_CON);
dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 1);
if (!dma_wr_buf)
return -ENOMEM;
wpaddr = dma_map_single(i2c->dev, dma_wr_buf,
msgs->len, DMA_TO_DEVICE);
if (dma_mapping_error(i2c->dev, wpaddr)) {
i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
return -ENOMEM;
}
dma_rd_buf = i2c_get_dma_safe_msg_buf((msgs + 1), 1);
if (!dma_rd_buf) {
dma_unmap_single(i2c->dev, wpaddr,
msgs->len, DMA_TO_DEVICE);
i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
return -ENOMEM;
}
rpaddr = dma_map_single(i2c->dev, dma_rd_buf,
(msgs + 1)->len,
DMA_FROM_DEVICE);
if (dma_mapping_error(i2c->dev, rpaddr)) {
dma_unmap_single(i2c->dev, wpaddr,
msgs->len, DMA_TO_DEVICE);
i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
i2c_put_dma_safe_msg_buf(dma_rd_buf, (msgs + 1), false);
return -ENOMEM;
}
if (i2c->dev_comp->max_dma_support > 32) {
reg_4g_mode = upper_32_bits(wpaddr);
writel(reg_4g_mode, i2c->pdmabase + OFFSET_TX_4G_MODE);
reg_4g_mode = upper_32_bits(rpaddr);
writel(reg_4g_mode, i2c->pdmabase + OFFSET_RX_4G_MODE);
}
writel((u32)wpaddr, i2c->pdmabase + OFFSET_TX_MEM_ADDR);
writel((u32)rpaddr, i2c->pdmabase + OFFSET_RX_MEM_ADDR);
writel(msgs->len, i2c->pdmabase + OFFSET_TX_LEN);
writel((msgs + 1)->len, i2c->pdmabase + OFFSET_RX_LEN);
}
writel(I2C_DMA_START_EN, i2c->pdmabase + OFFSET_EN);
if (!i2c->auto_restart) {
start_reg = I2C_TRANSAC_START;
} else {
start_reg = I2C_TRANSAC_START | I2C_RS_MUL_TRIG;
if (left_num >= 1)
start_reg |= I2C_RS_MUL_CNFG;
}
mtk_i2c_writew(i2c, start_reg, OFFSET_START);
ret = wait_for_completion_timeout(&i2c->msg_complete,
i2c->adap.timeout);
/* Clear interrupt mask */
mtk_i2c_writew(i2c, ~(restart_flag | I2C_HS_NACKERR | I2C_ACKERR |
I2C_ARB_LOST | I2C_TRANSAC_COMP), OFFSET_INTR_MASK);
if (i2c->op == I2C_MASTER_WR) {
dma_unmap_single(i2c->dev, wpaddr,
msgs->len, DMA_TO_DEVICE);
i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true);
} else if (i2c->op == I2C_MASTER_RD) {
dma_unmap_single(i2c->dev, rpaddr,
msgs->len, DMA_FROM_DEVICE);
i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, true);
} else {
dma_unmap_single(i2c->dev, wpaddr, msgs->len,
DMA_TO_DEVICE);
dma_unmap_single(i2c->dev, rpaddr, (msgs + 1)->len,
DMA_FROM_DEVICE);
i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true);
i2c_put_dma_safe_msg_buf(dma_rd_buf, (msgs + 1), true);
}
if (ret == 0) {
dev_dbg(i2c->dev, "addr: %x, transfer timeout\n", msgs->addr);
i2c_dump_register(i2c);
mtk_i2c_init_hw(i2c);
return -ETIMEDOUT;
}
if (i2c->irq_stat & (I2C_HS_NACKERR | I2C_ACKERR)) {
dev_dbg(i2c->dev, "addr: %x, transfer ACK error\n", msgs->addr);
mtk_i2c_init_hw(i2c);
return -ENXIO;
}
return 0;
}
static int mtk_i2c_transfer(struct i2c_adapter *adap,
struct i2c_msg msgs[], int num)
{
int ret;
int left_num = num;
struct mtk_i2c *i2c = i2c_get_adapdata(adap);
ret = mtk_i2c_clock_enable(i2c);
if (ret)
return ret;
i2c->auto_restart = i2c->dev_comp->auto_restart;
/* checking if we can skip restart and optimize using WRRD mode */
if (i2c->auto_restart && num == 2) {
if (!(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD) &&
msgs[0].addr == msgs[1].addr) {
i2c->auto_restart = 0;
}
}
if (i2c->auto_restart && num >= 2 &&
i2c->speed_hz > I2C_MAX_FAST_MODE_PLUS_FREQ)
/* ignore the first restart irq after the master code,
* otherwise the first transfer will be discarded.
*/
i2c->ignore_restart_irq = true;
else
i2c->ignore_restart_irq = false;
while (left_num--) {
if (!msgs->buf) {
dev_dbg(i2c->dev, "data buffer is NULL.\n");
ret = -EINVAL;
goto err_exit;
}
if (msgs->flags & I2C_M_RD)
i2c->op = I2C_MASTER_RD;
else
i2c->op = I2C_MASTER_WR;
if (!i2c->auto_restart) {
if (num > 1) {
/* combined two messages into one transaction */
i2c->op = I2C_MASTER_WRRD;
left_num--;
}
}
/* always use DMA mode. */
ret = mtk_i2c_do_transfer(i2c, msgs, num, left_num);
if (ret < 0)
goto err_exit;
msgs++;
}
/* the return value is number of executed messages */
ret = num;
err_exit:
mtk_i2c_clock_disable(i2c);
return ret;
}
static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id)
{
struct mtk_i2c *i2c = dev_id;
u16 restart_flag = 0;
u16 intr_stat;
if (i2c->auto_restart)
restart_flag = I2C_RS_TRANSFER;
intr_stat = mtk_i2c_readw(i2c, OFFSET_INTR_STAT);
mtk_i2c_writew(i2c, intr_stat, OFFSET_INTR_STAT);
/*
* when occurs ack error, i2c controller generate two interrupts
* first is the ack error interrupt, then the complete interrupt
* i2c->irq_stat need keep the two interrupt value.
*/
i2c->irq_stat |= intr_stat;
if (i2c->ignore_restart_irq && (i2c->irq_stat & restart_flag)) {
i2c->ignore_restart_irq = false;
i2c->irq_stat = 0;
mtk_i2c_writew(i2c, I2C_RS_MUL_CNFG | I2C_RS_MUL_TRIG |
I2C_TRANSAC_START, OFFSET_START);
} else {
if (i2c->irq_stat & (I2C_TRANSAC_COMP | restart_flag))
complete(&i2c->msg_complete);
}
return IRQ_HANDLED;
}
static u32 mtk_i2c_functionality(struct i2c_adapter *adap)
{
if (i2c_check_quirks(adap, I2C_AQ_NO_ZERO_LEN))
return I2C_FUNC_I2C |
(I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
else
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}
static const struct i2c_algorithm mtk_i2c_algorithm = {
.master_xfer = mtk_i2c_transfer,
.functionality = mtk_i2c_functionality,
};
static int mtk_i2c_parse_dt(struct device_node *np, struct mtk_i2c *i2c)
{
int ret;
ret = of_property_read_u32(np, "clock-frequency", &i2c->speed_hz);
if (ret < 0)
i2c->speed_hz = I2C_MAX_STANDARD_MODE_FREQ;
ret = of_property_read_u32(np, "clock-div", &i2c->clk_src_div);
if (ret < 0)
return ret;
if (i2c->clk_src_div == 0)
return -EINVAL;
i2c->have_pmic = of_property_read_bool(np, "mediatek,have-pmic");
i2c->use_push_pull =
of_property_read_bool(np, "mediatek,use-push-pull");
i2c_parse_fw_timings(i2c->dev, &i2c->timing_info, true);
return 0;
}
static int mtk_i2c_probe(struct platform_device *pdev)
{
int ret = 0;
struct mtk_i2c *i2c;
struct clk *clk;
struct resource *res;
int irq;
i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
if (!i2c)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
i2c->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(i2c->base))
return PTR_ERR(i2c->base);
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
i2c->pdmabase = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(i2c->pdmabase))
return PTR_ERR(i2c->pdmabase);
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
init_completion(&i2c->msg_complete);
i2c->dev_comp = of_device_get_match_data(&pdev->dev);
i2c->adap.dev.of_node = pdev->dev.of_node;
i2c->dev = &pdev->dev;
i2c->adap.dev.parent = &pdev->dev;
i2c->adap.owner = THIS_MODULE;
i2c->adap.algo = &mtk_i2c_algorithm;
i2c->adap.quirks = i2c->dev_comp->quirks;
i2c->adap.timeout = 2 * HZ;
i2c->adap.retries = 1;
i2c->adap.bus_regulator = devm_regulator_get_optional(&pdev->dev, "vbus");
if (IS_ERR(i2c->adap.bus_regulator)) {
if (PTR_ERR(i2c->adap.bus_regulator) == -ENODEV)
i2c->adap.bus_regulator = NULL;
else
return PTR_ERR(i2c->adap.bus_regulator);
}
ret = mtk_i2c_parse_dt(pdev->dev.of_node, i2c);
if (ret)
return -EINVAL;
if (i2c->have_pmic && !i2c->dev_comp->pmic_i2c)
return -EINVAL;
i2c->clk_main = devm_clk_get(&pdev->dev, "main");
if (IS_ERR(i2c->clk_main)) {
dev_err(&pdev->dev, "cannot get main clock\n");
return PTR_ERR(i2c->clk_main);
}
i2c->clk_dma = devm_clk_get(&pdev->dev, "dma");
if (IS_ERR(i2c->clk_dma)) {
dev_err(&pdev->dev, "cannot get dma clock\n");
return PTR_ERR(i2c->clk_dma);
}
i2c->clk_arb = devm_clk_get(&pdev->dev, "arb");
if (IS_ERR(i2c->clk_arb))
i2c->clk_arb = NULL;
clk = i2c->clk_main;
if (i2c->have_pmic) {
i2c->clk_pmic = devm_clk_get(&pdev->dev, "pmic");
if (IS_ERR(i2c->clk_pmic)) {
dev_err(&pdev->dev, "cannot get pmic clock\n");
return PTR_ERR(i2c->clk_pmic);
}
clk = i2c->clk_pmic;
}
strlcpy(i2c->adap.name, I2C_DRV_NAME, sizeof(i2c->adap.name));
ret = mtk_i2c_set_speed(i2c, clk_get_rate(clk));
if (ret) {
dev_err(&pdev->dev, "Failed to set the speed.\n");
return -EINVAL;
}
if (i2c->dev_comp->max_dma_support > 32) {
ret = dma_set_mask(&pdev->dev,
DMA_BIT_MASK(i2c->dev_comp->max_dma_support));
if (ret) {
dev_err(&pdev->dev, "dma_set_mask return error.\n");
return ret;
}
}
ret = mtk_i2c_clock_enable(i2c);
if (ret) {
dev_err(&pdev->dev, "clock enable failed!\n");
return ret;
}
mtk_i2c_init_hw(i2c);
mtk_i2c_clock_disable(i2c);
ret = devm_request_irq(&pdev->dev, irq, mtk_i2c_irq,
IRQF_NO_SUSPEND | IRQF_TRIGGER_NONE,
dev_name(&pdev->dev), i2c);
if (ret < 0) {
dev_err(&pdev->dev,
"Request I2C IRQ %d fail\n", irq);
return ret;
}
i2c_set_adapdata(&i2c->adap, i2c);
ret = i2c_add_adapter(&i2c->adap);
if (ret)
return ret;
platform_set_drvdata(pdev, i2c);
return 0;
}
static int mtk_i2c_remove(struct platform_device *pdev)
{
struct mtk_i2c *i2c = platform_get_drvdata(pdev);
i2c_del_adapter(&i2c->adap);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int mtk_i2c_suspend_noirq(struct device *dev)
{
struct mtk_i2c *i2c = dev_get_drvdata(dev);
i2c_mark_adapter_suspended(&i2c->adap);
return 0;
}
static int mtk_i2c_resume_noirq(struct device *dev)
{
int ret;
struct mtk_i2c *i2c = dev_get_drvdata(dev);
ret = mtk_i2c_clock_enable(i2c);
if (ret) {
dev_err(dev, "clock enable failed!\n");
return ret;
}
mtk_i2c_init_hw(i2c);
mtk_i2c_clock_disable(i2c);
i2c_mark_adapter_resumed(&i2c->adap);
return 0;
}
#endif
static const struct dev_pm_ops mtk_i2c_pm = {
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mtk_i2c_suspend_noirq,
mtk_i2c_resume_noirq)
};
static struct platform_driver mtk_i2c_driver = {
.probe = mtk_i2c_probe,
.remove = mtk_i2c_remove,
.driver = {
.name = I2C_DRV_NAME,
.pm = &mtk_i2c_pm,
.of_match_table = of_match_ptr(mtk_i2c_of_match),
},
};
module_platform_driver(mtk_i2c_driver);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("MediaTek I2C Bus Driver");
MODULE_AUTHOR("Xudong Chen <xudong.chen@mediatek.com>");