[PATCH v5 3/3] I2C: mediatek: Add driver for MediaTek MT8173 I2C controller
Eddie Huang
eddie.huang at mediatek.com
Fri Mar 20 23:05:22 PDT 2015
Add mediatek MT8173 I2C controller driver. Compare to I2C controller
of earlier mediatek SoC, MT8173 fix write-then-read limitation, and
also increase message size to 64kb.
Signed-off-by: Xudong Chen <xudong.chen at mediatek.com>
Signed-off-by: Liguo Zhang <liguo.zhang at mediatek.com>
Signed-off-by: Eddie Huang <eddie.huang at mediatek.com>
---
drivers/i2c/busses/i2c-mt65xx.c | 107 ++++++++++++++++++++++++++++------------
1 file changed, 75 insertions(+), 32 deletions(-)
diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index 3940112..17607c8 100644
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -33,10 +33,13 @@
#include <linux/of_irq.h>
#include <linux/clk.h>
+#define I2C_RS_TRANSFER (1 << 4)
#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_TIMING_STEP_DIV_MASK (0x3f << 0)
#define I2C_TIMING_SAMPLE_COUNT_MASK (0x7 << 0)
#define I2C_TIMING_SAMPLE_DIV_MASK (0x7 << 8)
@@ -67,6 +70,9 @@
#define MAX_MSG_NUM_MT6577 1
#define MAX_DMA_TRANS_SIZE_MT6577 255
#define MAX_WRRD_TRANS_SIZE_MT6577 31
+#define MAX_MSG_NUM_MT8173 65535
+#define MAX_DMA_TRANS_SIZE_MT8173 65535
+#define MAX_WRRD_TRANS_SIZE_MT8173 65535
#define MAX_SAMPLE_CNT_DIV 8
#define MAX_STEP_CNT_DIV 64
#define MAX_HS_STEP_CNT_DIV 8
@@ -81,6 +87,7 @@
#define COMPAT_MT6577 (0x1 << 0)
#define COMPAT_MT6589 (0x1 << 1)
+#define COMPAT_MT8173 (0x1 << 2)
#define I2C_DRV_NAME "mt-i2c"
@@ -172,6 +179,7 @@ struct mtk_i2c {
static const struct of_device_id mtk_i2c_of_match[] = {
{ .compatible = "mediatek,mt6577-i2c", .data = (void *)COMPAT_MT6577 },
{ .compatible = "mediatek,mt6589-i2c", .data = (void *)COMPAT_MT6589 },
+ { .compatible = "mediatek,mt8173-i2c", .data = (void *)COMPAT_MT8173 },
{}
};
MODULE_DEVICE_TABLE(of, mtk_i2c_match);
@@ -236,7 +244,7 @@ static inline void mtk_i2c_init_hw(struct mtk_i2c *i2c)
else
mtk_i2c_writew(I2C_IO_CONFIG_OPEN_DRAIN, i2c, OFFSET_IO_CONFIG);
- if (i2c->platform_compat & COMPAT_MT6577)
+ if (i2c->platform_compat & (COMPAT_MT6577 | COMPAT_MT8173))
mtk_i2c_writew(I2C_DCM_DISABLE, i2c, OFFSET_DCM_EN);
mtk_i2c_writew(i2c->timing_reg, i2c, OFFSET_TIMING);
@@ -320,10 +328,12 @@ static int i2c_set_speed(struct mtk_i2c *i2c, unsigned int clk_src_in_hz)
return 0;
}
-static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
+static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
+ int num, int left_num)
{
u16 addr_reg;
u16 control_reg;
+ u16 start_reg = 0;
u16 irqstat;
dma_addr_t rpaddr = 0;
dma_addr_t wpaddr = 0;
@@ -344,6 +354,8 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
control_reg |= I2C_CONTROL_RS;
if (i2c->op == I2C_MASTER_WRRD)
control_reg |= I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS;
+ if (left_num >= 1)
+ control_reg |= I2C_CONTROL_RS;
mtk_i2c_writew(control_reg, i2c, OFFSET_CONTROL);
/* set start condition */
@@ -361,13 +373,13 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
mtk_i2c_writew(addr_reg, i2c, OFFSET_SLAVE_ADDR);
/* Clear interrupt status */
- mtk_i2c_writew(I2C_HS_NACKERR | I2C_ACKERR | I2C_TRANSAC_COMP,
- i2c, OFFSET_INTR_STAT);
+ mtk_i2c_writew(I2C_RS_TRANSFER | I2C_HS_NACKERR | I2C_ACKERR
+ | I2C_TRANSAC_COMP, i2c, OFFSET_INTR_STAT);
mtk_i2c_writew(I2C_FIFO_ADDR_CLR, i2c, OFFSET_FIFO_ADDR_CLR);
/* Enable interrupt */
- mtk_i2c_writew(I2C_HS_NACKERR | I2C_ACKERR | I2C_TRANSAC_COMP,
- i2c, OFFSET_INTR_MASK);
+ mtk_i2c_writew(I2C_RS_TRANSFER | I2C_HS_NACKERR | I2C_ACKERR
+ | I2C_TRANSAC_COMP, i2c, OFFSET_INTR_MASK);
/* Set transfer and transaction len */
if (i2c->op == I2C_MASTER_WRRD) {
@@ -376,7 +388,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
mtk_i2c_writew(I2C_WRRD_TRANAC_VALUE, i2c, OFFSET_TRANSAC_LEN);
} else {
mtk_i2c_writew(msgs->len, i2c, OFFSET_TRANSFER_LEN);
- mtk_i2c_writew(I2C_RD_TRANAC_VALUE, i2c, OFFSET_TRANSAC_LEN);
+ mtk_i2c_writew(num, i2c, OFFSET_TRANSAC_LEN);
}
/* Prepare buffer data to start transfer */
@@ -422,7 +434,17 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
/* flush before sending start */
mb();
mtk_i2c_writel_dma(I2C_DMA_START_EN, i2c, OFFSET_EN);
- mtk_i2c_writew(I2C_TRANSAC_START, i2c, OFFSET_START);
+
+ if (i2c->platform_compat & (COMPAT_MT6577 | COMPAT_MT6589)) {
+ start_reg = I2C_TRANSAC_START;
+ } else if (i2c->platform_compat & COMPAT_MT8173) {
+ if (left_num >= 1)
+ start_reg = I2C_TRANSAC_START | I2C_RS_MUL_CNFG
+ | I2C_RS_MUL_TRIG;
+ else
+ start_reg = I2C_TRANSAC_START | I2C_RS_MUL_TRIG;
+ }
+ mtk_i2c_writew(start_reg, i2c, OFFSET_START);
tmo = wait_event_timeout(i2c->wait, i2c->trans_stop, tmo);
@@ -455,6 +477,10 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs)
return -EREMOTEIO;
}
+ if (irqstat & I2C_RS_TRANSFER)
+ dev_dbg(i2c->dev, "addr: %x, restart transfer interrupt.\n",
+ msgs->addr);
+
return 0;
}
@@ -469,28 +495,33 @@ static int mtk_i2c_transfer(struct i2c_adapter *adap,
if (ret)
return ret;
- if (msgs->buf == NULL) {
- 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;
+ while (left_num--) {
+ if (msgs->buf == NULL) {
+ dev_dbg(i2c->dev, "data buffer is NULL.\n");
+ ret = -EINVAL;
+ goto err_exit;
+ }
- if (num > 1) {
- /* combined two messages into one transaction */
- i2c->op = I2C_MASTER_WRRD;
- left_num--;
- }
+ if (msgs->flags & I2C_M_RD)
+ i2c->op = I2C_MASTER_RD;
+ else
+ i2c->op = I2C_MASTER_WR;
+
+ if (i2c->platform_compat & (COMPAT_MT6577 | COMPAT_MT6589)) {
+ 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);
- if (ret < 0)
- goto err_exit;
+ /* 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;
@@ -504,14 +535,14 @@ static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id)
struct mtk_i2c *i2c = dev_id;
/* Clear interrupt mask */
- mtk_i2c_writew(~(I2C_HS_NACKERR | I2C_ACKERR | I2C_TRANSAC_COMP),
- i2c, OFFSET_INTR_MASK);
+ mtk_i2c_writew(~(I2C_RS_TRANSFER | I2C_HS_NACKERR | I2C_ACKERR
+ | I2C_TRANSAC_COMP), i2c, OFFSET_INTR_MASK);
spin_lock(&i2c->irqlock);
i2c->irq_stat = mtk_i2c_readw(i2c, OFFSET_INTR_STAT);
i2c->trans_stop = true;
spin_unlock(&i2c->irqlock);
- mtk_i2c_writew(I2C_HS_NACKERR | I2C_ACKERR
+ mtk_i2c_writew(I2C_RS_TRANSFER | I2C_HS_NACKERR | I2C_ACKERR
| I2C_TRANSAC_COMP, i2c, OFFSET_INTR_STAT);
wake_up(&i2c->wait);
@@ -569,6 +600,14 @@ static const struct i2c_adapter_quirks mt6577_i2c_quirks = {
.max_comb_2nd_msg_len = MAX_WRRD_TRANS_SIZE_MT6577,
};
+static const struct i2c_adapter_quirks mt8173_i2c_quirks = {
+ .max_num_msgs = MAX_MSG_NUM_MT8173,
+ .max_write_len = MAX_DMA_TRANS_SIZE_MT8173,
+ .max_read_len = MAX_DMA_TRANS_SIZE_MT8173,
+ .max_comb_1st_msg_len = MAX_DMA_TRANS_SIZE_MT8173,
+ .max_comb_2nd_msg_len = MAX_WRRD_TRANS_SIZE_MT8173,
+};
+
static int mtk_i2c_probe(struct platform_device *pdev)
{
int ret = 0;
@@ -587,7 +626,8 @@ static int mtk_i2c_probe(struct platform_device *pdev)
return -EINVAL;
i2c->platform_compat = mtk_get_device_prop(pdev);
- if (i2c->have_pmic && (i2c->platform_compat & COMPAT_MT6577))
+ if (i2c->have_pmic && (i2c->platform_compat &
+ (COMPAT_MT6577 | COMPAT_MT8173)))
return -EINVAL;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -613,7 +653,10 @@ static int mtk_i2c_probe(struct platform_device *pdev)
i2c->adap.dev.parent = &pdev->dev;
i2c->adap.owner = THIS_MODULE;
i2c->adap.algo = &mtk_i2c_algorithm;
- i2c->adap.quirks = &mt6577_i2c_quirks;
+ if (i2c->platform_compat & COMPAT_MT8173)
+ i2c->adap.quirks = &mt8173_i2c_quirks;
+ else
+ i2c->adap.quirks = &mt6577_i2c_quirks;
i2c->adap.timeout = 2 * HZ;
i2c->adap.retries = 1;
--
1.8.1.1.dirty
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