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path: root/drivers/i2c/busses/i2c-wmt.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-wmt.c')
-rw-r--r--drivers/i2c/busses/i2c-wmt.c117
1 files changed, 34 insertions, 83 deletions
diff --git a/drivers/i2c/busses/i2c-wmt.c b/drivers/i2c/busses/i2c-wmt.c
index 76118abc6e10..ec2a8da134e5 100644
--- a/drivers/i2c/busses/i2c-wmt.c
+++ b/drivers/i2c/busses/i2c-wmt.c
@@ -74,9 +74,6 @@
#define MCR_APB_96M 7
#define MCR_APB_166M 12
-#define I2C_MODE_STANDARD 0
-#define I2C_MODE_FAST 1
-
#define WMT_I2C_TIMEOUT (msecs_to_jiffies(1000))
struct wmt_i2c_dev {
@@ -85,7 +82,7 @@ struct wmt_i2c_dev {
struct device *dev;
void __iomem *base;
struct clk *clk;
- int mode;
+ u16 tcr;
int irq;
u16 cmd_status;
};
@@ -109,6 +106,12 @@ static int wmt_i2c_wait_bus_not_busy(struct wmt_i2c_dev *i2c_dev)
static int wmt_check_status(struct wmt_i2c_dev *i2c_dev)
{
int ret = 0;
+ unsigned long wait_result;
+
+ wait_result = wait_for_completion_timeout(&i2c_dev->complete,
+ msecs_to_jiffies(500));
+ if (!wait_result)
+ return -ETIMEDOUT;
if (i2c_dev->cmd_status & ISR_NACK_ADDR)
ret = -EIO;
@@ -119,21 +122,13 @@ static int wmt_check_status(struct wmt_i2c_dev *i2c_dev)
return ret;
}
-static int wmt_i2c_write(struct i2c_adapter *adap, struct i2c_msg *pmsg,
+static int wmt_i2c_write(struct wmt_i2c_dev *i2c_dev, struct i2c_msg *pmsg,
int last)
{
- struct wmt_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
- u16 val, tcr_val;
+ u16 val, tcr_val = i2c_dev->tcr;
int ret;
- unsigned long wait_result;
int xfer_len = 0;
- if (!(pmsg->flags & I2C_M_NOSTART)) {
- ret = wmt_i2c_wait_bus_not_busy(i2c_dev);
- if (ret < 0)
- return ret;
- }
-
if (pmsg->len == 0) {
/*
* We still need to run through the while (..) once, so
@@ -148,20 +143,12 @@ static int wmt_i2c_write(struct i2c_adapter *adap, struct i2c_msg *pmsg,
if (!(pmsg->flags & I2C_M_NOSTART)) {
val = readw(i2c_dev->base + REG_CR);
val &= ~CR_TX_END;
- writew(val, i2c_dev->base + REG_CR);
-
- val = readw(i2c_dev->base + REG_CR);
val |= CR_CPU_RDY;
writew(val, i2c_dev->base + REG_CR);
}
reinit_completion(&i2c_dev->complete);
- if (i2c_dev->mode == I2C_MODE_STANDARD)
- tcr_val = TCR_STANDARD_MODE;
- else
- tcr_val = TCR_FAST_MODE;
-
tcr_val |= (TCR_MASTER_WRITE | (pmsg->addr & TCR_SLAVE_ADDR_MASK));
writew(tcr_val, i2c_dev->base + REG_TCR);
@@ -173,12 +160,6 @@ static int wmt_i2c_write(struct i2c_adapter *adap, struct i2c_msg *pmsg,
}
while (xfer_len < pmsg->len) {
- wait_result = wait_for_completion_timeout(&i2c_dev->complete,
- msecs_to_jiffies(500));
-
- if (wait_result == 0)
- return -ETIMEDOUT;
-
ret = wmt_check_status(i2c_dev);
if (ret)
return ret;
@@ -210,47 +191,24 @@ static int wmt_i2c_write(struct i2c_adapter *adap, struct i2c_msg *pmsg,
return 0;
}
-static int wmt_i2c_read(struct i2c_adapter *adap, struct i2c_msg *pmsg,
- int last)
+static int wmt_i2c_read(struct wmt_i2c_dev *i2c_dev, struct i2c_msg *pmsg)
{
- struct wmt_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
- u16 val, tcr_val;
+ u16 val, tcr_val = i2c_dev->tcr;
int ret;
- unsigned long wait_result;
u32 xfer_len = 0;
- if (!(pmsg->flags & I2C_M_NOSTART)) {
- ret = wmt_i2c_wait_bus_not_busy(i2c_dev);
- if (ret < 0)
- return ret;
- }
-
- val = readw(i2c_dev->base + REG_CR);
- val &= ~CR_TX_END;
- writew(val, i2c_dev->base + REG_CR);
-
val = readw(i2c_dev->base + REG_CR);
- val &= ~CR_TX_NEXT_NO_ACK;
- writew(val, i2c_dev->base + REG_CR);
+ val &= ~(CR_TX_END | CR_TX_NEXT_NO_ACK);
- if (!(pmsg->flags & I2C_M_NOSTART)) {
- val = readw(i2c_dev->base + REG_CR);
+ if (!(pmsg->flags & I2C_M_NOSTART))
val |= CR_CPU_RDY;
- writew(val, i2c_dev->base + REG_CR);
- }
- if (pmsg->len == 1) {
- val = readw(i2c_dev->base + REG_CR);
+ if (pmsg->len == 1)
val |= CR_TX_NEXT_NO_ACK;
- writew(val, i2c_dev->base + REG_CR);
- }
- reinit_completion(&i2c_dev->complete);
+ writew(val, i2c_dev->base + REG_CR);
- if (i2c_dev->mode == I2C_MODE_STANDARD)
- tcr_val = TCR_STANDARD_MODE;
- else
- tcr_val = TCR_FAST_MODE;
+ reinit_completion(&i2c_dev->complete);
tcr_val |= TCR_MASTER_READ | (pmsg->addr & TCR_SLAVE_ADDR_MASK);
@@ -263,12 +221,6 @@ static int wmt_i2c_read(struct i2c_adapter *adap, struct i2c_msg *pmsg,
}
while (xfer_len < pmsg->len) {
- wait_result = wait_for_completion_timeout(&i2c_dev->complete,
- msecs_to_jiffies(500));
-
- if (!wait_result)
- return -ETIMEDOUT;
-
ret = wmt_check_status(i2c_dev);
if (ret)
return ret;
@@ -276,15 +228,10 @@ static int wmt_i2c_read(struct i2c_adapter *adap, struct i2c_msg *pmsg,
pmsg->buf[xfer_len] = readw(i2c_dev->base + REG_CDR) >> 8;
xfer_len++;
- if (xfer_len == pmsg->len - 1) {
- val = readw(i2c_dev->base + REG_CR);
- val |= (CR_TX_NEXT_NO_ACK | CR_CPU_RDY);
- writew(val, i2c_dev->base + REG_CR);
- } else {
- val = readw(i2c_dev->base + REG_CR);
- val |= CR_CPU_RDY;
- writew(val, i2c_dev->base + REG_CR);
- }
+ val = readw(i2c_dev->base + REG_CR) | CR_CPU_RDY;
+ if (xfer_len == pmsg->len - 1)
+ val |= CR_TX_NEXT_NO_ACK;
+ writew(val, i2c_dev->base + REG_CR);
}
return 0;
@@ -295,17 +242,22 @@ static int wmt_i2c_xfer(struct i2c_adapter *adap,
int num)
{
struct i2c_msg *pmsg;
- int i, is_last;
+ int i;
int ret = 0;
+ struct wmt_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
for (i = 0; ret >= 0 && i < num; i++) {
- is_last = ((i + 1) == num);
-
pmsg = &msgs[i];
+ if (!(pmsg->flags & I2C_M_NOSTART)) {
+ ret = wmt_i2c_wait_bus_not_busy(i2c_dev);
+ if (ret < 0)
+ return ret;
+ }
+
if (pmsg->flags & I2C_M_RD)
- ret = wmt_i2c_read(adap, pmsg, is_last);
+ ret = wmt_i2c_read(i2c_dev, pmsg);
else
- ret = wmt_i2c_write(adap, pmsg, is_last);
+ ret = wmt_i2c_write(i2c_dev, pmsg, (i + 1) == num);
}
return (ret < 0) ? ret : i;
@@ -359,10 +311,10 @@ static int wmt_i2c_reset_hardware(struct wmt_i2c_dev *i2c_dev)
readw(i2c_dev->base + REG_CSR); /* read clear */
writew(ISR_WRITE_ALL, i2c_dev->base + REG_ISR);
- if (i2c_dev->mode == I2C_MODE_STANDARD)
- writew(SCL_TIMEOUT(128) | TR_STD, i2c_dev->base + REG_TR);
- else
+ if (i2c_dev->tcr == TCR_FAST_MODE)
writew(SCL_TIMEOUT(128) | TR_HS, i2c_dev->base + REG_TR);
+ else
+ writew(SCL_TIMEOUT(128) | TR_STD, i2c_dev->base + REG_TR);
return 0;
}
@@ -395,10 +347,9 @@ static int wmt_i2c_probe(struct platform_device *pdev)
return PTR_ERR(i2c_dev->clk);
}
- i2c_dev->mode = I2C_MODE_STANDARD;
err = of_property_read_u32(np, "clock-frequency", &clk_rate);
if (!err && (clk_rate == I2C_MAX_FAST_MODE_FREQ))
- i2c_dev->mode = I2C_MODE_FAST;
+ i2c_dev->tcr = TCR_FAST_MODE;
i2c_dev->dev = &pdev->dev;
generated by cgit v1.2.3 (git 2.39.0) at 2025-01-02 14:00:28 +0300