i2c: imx: Use correct function to write to register

commit 6c782a5ea56a799658e213a78dc1455264938afa upstream.

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. The platform is imx.

Signed-off-by: Michail G Etairidis <m.etairidis@beck-ipc.com>
Fixes: ce1a78840ff7 ("i2c: imx: add DMA support for freescale i2c driver")
Fixes: 054b62d9f25c ("i2c: imx: fix the i2c bus hang issue when do repeat restart")
Acked-by: Fugang Duan <fugang.duan@nxp.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
[bwh: Backported to 3.16: drop changes in i2c_imx_dma_read()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index aa8bc146718bfc13c562e11322ddf36d9442f2c7..494a9e7e88c44add3c27121ca21315517c018af7 100644 (file)
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -542,9 +542,9 @@ 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,