[PATCH v6] i2c: mt8173: add 4GB mode support in i2c driver.

From: Liguo Zhang
Date: Mon Feb 01 2016 - 20:19:47 EST


If 4GB mode is enable, we should add 4gb mode support in i2c driver.
Set 4GB mode register to support 4GB mode.

Signed-off-by: Liguo Zhang <liguo.zhang@xxxxxxxxxxxx>
---
change in v6:
Remove unnecessary init for reg_4g_mode.
change in v5:
Use BIT_ULL() to fix kernel building warning.
change in v4:
Use BIT_ULL() to fix kernel building warning.
change in v3:
Only inline the computation of reg_4g_mode in mtk_i2c_set_4g_mode().
change in v2:
Define a static inline function mtk_i2c_set_4g_mode() for support 4g mode.
---
drivers/i2c/busses/i2c-mt65xx.c | 42 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 42 insertions(+)

diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index aec8e6c..453358b 100644
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -60,6 +60,7 @@
#define I2C_DMA_INT_FLAG_NONE 0x0000
#define I2C_DMA_CLR_FLAG 0x0000
#define I2C_DMA_HARD_RST 0x0002
+#define I2C_DMA_4G_MODE 0x0001

#define I2C_DEFAULT_SPEED 100000 /* hz */
#define MAX_FS_MODE_SPEED 400000
@@ -88,6 +89,8 @@ enum DMA_REGS_OFFSET {
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 {
@@ -133,6 +136,7 @@ struct mtk_i2c_compatible {
unsigned char dcm: 1;
unsigned char auto_restart: 1;
unsigned char aux_len_reg: 1;
+ unsigned char support_33bits: 1;
};

struct mtk_i2c {
@@ -182,6 +186,7 @@ static const struct mtk_i2c_compatible mt6577_compat = {
.dcm = 1,
.auto_restart = 0,
.aux_len_reg = 0,
+ .support_33bits = 0,
};

static const struct mtk_i2c_compatible mt6589_compat = {
@@ -190,6 +195,7 @@ static const struct mtk_i2c_compatible mt6589_compat = {
.dcm = 0,
.auto_restart = 0,
.aux_len_reg = 0,
+ .support_33bits = 0,
};

static const struct mtk_i2c_compatible mt8173_compat = {
@@ -198,6 +204,7 @@ static const struct mtk_i2c_compatible mt8173_compat = {
.dcm = 1,
.auto_restart = 1,
.aux_len_reg = 1,
+ .support_33bits = 1,
};

static const struct of_device_id mtk_i2c_of_match[] = {
@@ -366,6 +373,11 @@ static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk,
return 0;
}

+static inline u32 mtk_i2c_set_4g_mode(dma_addr_t addr)
+{
+ return (addr & BIT_ULL(32)) ? I2C_DMA_4G_MODE : I2C_DMA_CLR_FLAG;
+}
+
static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
int num, int left_num)
{
@@ -373,6 +385,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
u16 start_reg;
u16 control_reg;
u16 restart_flag = 0;
+ u32 reg_4g_mode;
dma_addr_t rpaddr = 0;
dma_addr_t wpaddr = 0;
int ret;
@@ -439,6 +452,12 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
msgs->len, DMA_FROM_DEVICE);
if (dma_mapping_error(i2c->dev, rpaddr))
return -ENOMEM;
+
+ if (i2c->dev_comp->support_33bits) {
+ reg_4g_mode = mtk_i2c_set_4g_mode(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) {
@@ -448,6 +467,12 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
msgs->len, DMA_TO_DEVICE);
if (dma_mapping_error(i2c->dev, wpaddr))
return -ENOMEM;
+
+ if (i2c->dev_comp->support_33bits) {
+ reg_4g_mode = mtk_i2c_set_4g_mode(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 {
@@ -465,6 +490,15 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
msgs->len, DMA_TO_DEVICE);
return -ENOMEM;
}
+
+ if (i2c->dev_comp->support_33bits) {
+ reg_4g_mode = mtk_i2c_set_4g_mode(wpaddr);
+ writel(reg_4g_mode, i2c->pdmabase + OFFSET_TX_4G_MODE);
+
+ reg_4g_mode = mtk_i2c_set_4g_mode(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);
@@ -729,6 +763,14 @@ static int mtk_i2c_probe(struct platform_device *pdev)
return -EINVAL;
}

+ if (i2c->dev_comp->support_33bits) {
+ ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(33));
+ 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");
--
1.8.1.1.dirty