[PATCH v6 4/6] i2c: mediatek: Add i2c and apdma sync in i2c driver

From: Qii Wang
Date: Mon Mar 11 2019 - 01:41:36 EST


When i2c and apdma use different source clocks, we should enable
synchronization between them.

Signed-off-by: Qii Wang <qii.wang@xxxxxxxxxxxx>
Reviewed-by: Nicolas Boichat <drinkcat@xxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-mt65xx.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index 1a7235e..6137ad7 100644
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -77,6 +77,8 @@
#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"
@@ -169,6 +171,7 @@ struct mtk_i2c_compatible {
unsigned char aux_len_reg: 1;
unsigned char support_33bits: 1;
unsigned char timing_adjust: 1;
+ unsigned char dma_sync: 1;
};

struct mtk_i2c {
@@ -218,6 +221,7 @@ struct mtk_i2c {
.aux_len_reg = 1,
.support_33bits = 1,
.timing_adjust = 1,
+ .dma_sync = 0,
};

static const struct mtk_i2c_compatible mt6577_compat = {
@@ -229,6 +233,7 @@ struct mtk_i2c {
.aux_len_reg = 0,
.support_33bits = 0,
.timing_adjust = 0,
+ .dma_sync = 0,
};

static const struct mtk_i2c_compatible mt6589_compat = {
@@ -240,6 +245,7 @@ struct mtk_i2c {
.aux_len_reg = 0,
.support_33bits = 0,
.timing_adjust = 0,
+ .dma_sync = 0,
};

static const struct mtk_i2c_compatible mt7622_compat = {
@@ -251,6 +257,7 @@ struct mtk_i2c {
.aux_len_reg = 1,
.support_33bits = 0,
.timing_adjust = 0,
+ .dma_sync = 0,
};

static const struct mtk_i2c_compatible mt8173_compat = {
@@ -261,6 +268,7 @@ struct mtk_i2c {
.aux_len_reg = 1,
.support_33bits = 1,
.timing_adjust = 0,
+ .dma_sync = 0,
};

static const struct of_device_id mtk_i2c_of_match[] = {
@@ -360,6 +368,9 @@ static void mtk_i2c_init_hw(struct mtk_i2c *i2c)

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);

--
1.7.9.5