gpio: pca953x: Use correct u16 value for register word write

[ Upstream commit 9b8e3ec3 ]

The current implementation only uses the first byte in val,
the second byte is always 0. Change it to use cpu_to_le16
to write the two bytes into the register

Cc: stable@vger.kernel.org
Signed-off-by: Yong Li <sdliyong@gmail.com>
Reviewed-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

drivers/gpio/gpio-pca953x.c

@@ -21,6 +21,7 @@
 #ifdef CONFIG_OF_GPIO
 #include <linux/of_platform.h>
 #endif
+#include <asm/unaligned.h>
 
 #define PCA953X_INPUT		0
 #define PCA953X_OUTPUT		1
@@ -154,7 +155,7 @@ 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, cpu_to_le16(get_unaligned((u16 *)val)));
 			break;
 		case PCA957X_TYPE:
 			ret = i2c_smbus_write_byte_data(chip->client, reg << 1,