[PATCH] backlight: ili922x: add an error code check in ili922x_write

[Su Hui <suhui@xxxxxxxxxxxx>]

Clang static analyzer complains that value stored to 'ret' is never read.
Return the error code when spi_sync() failed.

Signed-off-by: Su Hui <suhui@xxxxxxxxxxxx>
---
 drivers/video/backlight/ili922x.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/video/backlight/ili922x.c b/drivers/video/backlight/ili922x.c
index e7b6bd827986..47b872ac64a7 100644
--- a/drivers/video/backlight/ili922x.c
+++ b/drivers/video/backlight/ili922x.c
@@ -269,6 +269,10 @@ static int ili922x_write(struct spi_device *spi, u8 reg, u16 value)
 	spi_message_add_tail(&xfer_regindex, &msg);
 
 	ret = spi_sync(spi, &msg);
+	if (ret < 0) {
+		dev_err(&spi->dev, "Error sending SPI message 0x%x", ret);
+		return ret;
+	}
 
 	spi_message_init(&msg);
 	tbuf[0] = set_tx_byte(START_BYTE(ili922x_id, START_RS_REG,
-- 
2.30.2