Re: [PATCH] gpio: pca953x: Use correct u16 value for register word write

From: Phil Reid
Date: Tue Mar 29 2016 - 08:06:30 EST


G'day Yong,

One comment below.

On 29/03/2016 2:27 PM, Yong Li wrote:
The current implementation only uses the first byte in *val,
the second data is always 0. Change it to *(u16 *)val
to write the two bytes into the register

Signed-off-by: Yong Li <sdliyong@xxxxxxxxx>
---
drivers/gpio/gpio-pca953x.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index d0d3065..cf3d410 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -159,7 +159,7 @@ static int pca953x_write_regs(struct pca953x_chip *chip, int reg, u8 *val)
switch (chip->chip_type) {
case PCA953X_TYPE:
ret = i2c_smbus_write_word_data(chip->client,
- reg << 1, (u16) *val);
+ reg << 1, *(u16 *)val);
I don't think this is safe for systems that don't support unaligned memory access.


break;
case PCA957X_TYPE:
ret = i2c_smbus_write_byte_data(chip->client, reg << 1,



--
Regards
Phil Reid