i2c: sprd: Fix the i2c count issue

We found the I2C controller count register is unreliable sometimes,
that will cause I2C to lose data. Thus we can read the data count
from 'i2c_dev->count' instead of the I2C controller count register.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

diff --git a/drivers/i2c/busses/i2c-sprd.c b/drivers/i2c/busses/i2c-sprd.c
index 2fdad63a23a18b48f4c01e5b3587404730469813..4053259bccb8d704d9d386287086841690174844 100644 (file)
--- a/drivers/i2c/busses/i2c-sprd.c
+++ b/drivers/i2c/busses/i2c-sprd.c
@@ -368,13 +368,12 @@ static irqreturn_t sprd_i2c_isr_thread(int irq, void *dev_id)
        struct sprd_i2c *i2c_dev = dev_id;
        struct i2c_msg *msg = i2c_dev->msg;
        bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK);
        struct sprd_i2c *i2c_dev = dev_id;
        struct i2c_msg *msg = i2c_dev->msg;
        bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK);

-       u32 i2c_count = readl(i2c_dev->base + I2C_COUNT);

        u32 i2c_tran;
 
        if (msg->flags & I2C_M_RD)
                i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD;
        else
        u32 i2c_tran;
 
        if (msg->flags & I2C_M_RD)
                i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD;
        else

-               i2c_tran = i2c_count;
+               i2c_tran = i2c_dev->count;

 
        /*
         * If we got one ACK from slave when writing data, and we did not
 
        /*
         * If we got one ACK from slave when writing data, and we did not


@@ -412,14 +411,13 @@ static irqreturn_t sprd_i2c_isr(int irq, void *dev_id)
 {
        struct sprd_i2c *i2c_dev = dev_id;
        struct i2c_msg *msg = i2c_dev->msg;
 {
        struct sprd_i2c *i2c_dev = dev_id;
        struct i2c_msg *msg = i2c_dev->msg;

-       u32 i2c_count = readl(i2c_dev->base + I2C_COUNT);

        bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK);
        u32 i2c_tran;
 
        if (msg->flags & I2C_M_RD)
                i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD;
        else
        bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK);
        u32 i2c_tran;
 
        if (msg->flags & I2C_M_RD)
                i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD;
        else

-               i2c_tran = i2c_count;
+               i2c_tran = i2c_dev->count;

 
        /*
         * If we did not get one ACK from slave when writing data, then we
 
        /*
         * If we did not get one ACK from slave when writing data, then we