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

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>
diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index d0d3065..e66084c 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -18,6 +18,7 @@
 #include <linux/i2c.h>
 #include <linux/platform_data/pca953x.h>
 #include <linux/slab.h>
+#include <asm/unaligned.h>
 #include <linux/of_platform.h>
 #include <linux/acpi.h>
 
@@ -159,7 +160,7 @@
 		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,