[PATCH] i2c: i2c-imx: Use correct function to write to register
From: Michail Georgios Etairidis <hidden>
Date: 2017-06-09 13:28:19
Subsystem:
freescale imx i2c driver, i2c subsystem, i2c subsystem host drivers, the rest · Maintainers:
Oleksij Rempel, Wolfram Sang, Andi Shyti, Linus Torvalds
The i2c-imx driver incorrectly uses readb()/writeb() to read and write to the appropriate registers when performing a repeated start. The appropriate imx_i2c_read_reg()/imx_i2c_write_reg() functions should be used instead. Performing a repeated start results in a kernel panic. I am resubmitting this patch as the previous one was erroneous. This patch is based on the current upstream kernel code.
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 95ed171..54a47b4 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c@@ -734,9 +734,9 @@ static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx, * the first read operation, otherwise the first read cost * one extra clock cycle. */ - temp = readb(i2c_imx->base + IMX_I2C_I2CR); + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); temp |= I2CR_MTX; - writeb(temp, i2c_imx->base + IMX_I2C_I2CR); + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); } msgs->buf[msgs->len-1] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
@@ -857,9 +857,9 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, bo * the first read operation, otherwise the first read cost * one extra clock cycle. */ - temp = readb(i2c_imx->base + IMX_I2C_I2CR); + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); temp |= I2CR_MTX; - writeb(temp, i2c_imx->base + IMX_I2C_I2CR); + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); } } else if (i == (msgs->len - 2)) { dev_dbg(&i2c_imx->adapter.dev,