[PATCH v6 5/6] i2c: mediatek: Add i2c support for MediaTek MT8183

From: Qii Wang
Date: Mon Mar 11 2019 - 01:41:41 EST


Add i2c compatible for MT8183. Compare to MT2712 i2c controller,
MT8183 has different register offsets. Ltiming_reg is added to
adjust low width of SCL. Arb clock and dma_sync are needed.

Signed-off-by: Qii Wang <qii.wang@xxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-mt65xx.c | 62 +++++++++++++++++++++++++++++++++++++--
1 file changed, 60 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index 6137ad7..745b0d0 100644
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -133,6 +133,7 @@ enum I2C_REGS_OFFSET {
OFFSET_DEBUGCTRL,
OFFSET_TRANSFER_LEN_AUX,
OFFSET_CLOCK_DIV,
+ OFFSET_LTIMING,
};

static const u16 mt_i2c_regs_v1[] = {
@@ -162,6 +163,32 @@ enum I2C_REGS_OFFSET {
[OFFSET_CLOCK_DIV] = 0x70,
};

+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_TRANSFER_LEN_AUX] = 0x44,
+ [OFFSET_CLOCK_DIV] = 0x48,
+ [OFFSET_SOFTRESET] = 0x50,
+ [OFFSET_DEBUGSTAT] = 0xe0,
+ [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;
@@ -172,6 +199,7 @@ struct mtk_i2c_compatible {
unsigned char support_33bits: 1;
unsigned char timing_adjust: 1;
unsigned char dma_sync: 1;
+ unsigned char ltiming_adjust: 1;
};

struct mtk_i2c {
@@ -195,6 +223,7 @@ struct mtk_i2c {
enum mtk_trans_op op;
u16 timing_reg;
u16 high_speed_reg;
+ u16 ltiming_reg;
unsigned char auto_restart;
bool ignore_restart_irq;
const struct mtk_i2c_compatible *dev_comp;
@@ -222,6 +251,7 @@ struct mtk_i2c {
.support_33bits = 1,
.timing_adjust = 1,
.dma_sync = 0,
+ .ltiming_adjust = 0,
};

static const struct mtk_i2c_compatible mt6577_compat = {
@@ -234,6 +264,7 @@ struct mtk_i2c {
.support_33bits = 0,
.timing_adjust = 0,
.dma_sync = 0,
+ .ltiming_adjust = 0,
};

static const struct mtk_i2c_compatible mt6589_compat = {
@@ -246,6 +277,7 @@ struct mtk_i2c {
.support_33bits = 0,
.timing_adjust = 0,
.dma_sync = 0,
+ .ltiming_adjust = 0,
};

static const struct mtk_i2c_compatible mt7622_compat = {
@@ -258,6 +290,7 @@ struct mtk_i2c {
.support_33bits = 0,
.timing_adjust = 0,
.dma_sync = 0,
+ .ltiming_adjust = 0,
};

static const struct mtk_i2c_compatible mt8173_compat = {
@@ -269,6 +302,19 @@ struct mtk_i2c {
.support_33bits = 1,
.timing_adjust = 0,
.dma_sync = 0,
+ .ltiming_adjust = 0,
+};
+
+static const struct mtk_i2c_compatible mt8183_compat = {
+ .regs = mt_i2c_regs_v2,
+ .pmic_i2c = 0,
+ .dcm = 0,
+ .auto_restart = 1,
+ .aux_len_reg = 1,
+ .support_33bits = 1,
+ .timing_adjust = 1,
+ .dma_sync = 1,
+ .ltiming_adjust = 1,
};

static const struct of_device_id mtk_i2c_of_match[] = {
@@ -277,6 +323,7 @@ struct mtk_i2c {
{ .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 },
{}
};
MODULE_DEVICE_TABLE(of, mtk_i2c_of_match);
@@ -361,6 +408,8 @@ static void mtk_i2c_init_hw(struct mtk_i2c *i2c)

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 use i2c pin from PMIC mt6397 side, need set PATH_DIR first */
if (i2c->have_pmic)
@@ -460,6 +509,8 @@ 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;
int ret;

@@ -469,11 +520,11 @@ static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk)
if (target_speed > MAX_FS_MODE_SPEED) {
/* Set master code speed register */
ret = mtk_i2c_calculate_speed(i2c, clk_src, MAX_FS_MODE_SPEED,
- &step_cnt, &sample_cnt);
+ &l_step_cnt, &l_sample_cnt);
if (ret < 0)
return ret;

- i2c->timing_reg = (sample_cnt << 8) | step_cnt;
+ 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,
@@ -483,6 +534,10 @@ static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk)

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,
&step_cnt, &sample_cnt);
@@ -493,6 +548,9 @@ static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk)

/* Disable the high speed transaction */
i2c->high_speed_reg = I2C_TIME_CLR_VALUE;
+
+ if (i2c->dev_comp->ltiming_adjust)
+ i2c->ltiming_reg = (sample_cnt << 6) | step_cnt;
}

return 0;
--
1.7.9.5