[PATCH 1/1][SRU][OEM-OSP1-B][B][E][F] UBUNTU: SAUCE: platform/x86: dell-uart-backlight: move retry block

[AceLan Kao]

BugLink: https://bugs.launchpad.net/bugs/1863880

move the retry block to include not only read reply, but also write
function, so that the retry re-send the command, too.

Signed-off-by: AceLan Kao <acelan.kao at canonical.com>
---
 drivers/platform/x86/dell-uart-backlight.c | 23 +++++++++++-----------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/drivers/platform/x86/dell-uart-backlight.c b/drivers/platform/x86/dell-uart-backlight.c
index bddc4f228bf9..9b2b219f3b8f 100644
--- a/drivers/platform/x86/dell-uart-backlight.c
+++ b/drivers/platform/x86/dell-uart-backlight.c
@@ -320,23 +320,22 @@ static int dell_uart_get_scalar_status(struct dell_uart_backlight *dell_pdata)
 	int rx_len;
 	int status = 0, retry = 50;
 
-	dell_uart_dump_cmd(__func__, "tx: ", bl_cmd->cmd, bl_cmd->tx_len);
+	do {
+		dell_uart_dump_cmd(__func__, "tx: ", bl_cmd->cmd, bl_cmd->tx_len);
 
-	if (mutex_lock_killable(&dell_pdata->brightness_mutex) < 0) {
-		pr_debug("Failed to get mutex_lock");
-		return 0;
-	}
+		if (mutex_lock_killable(&dell_pdata->brightness_mutex) < 0) {
+			pr_debug("Failed to get mutex_lock");
+			return 0;
+		}
 
-	dell_uart_write(uart, bl_cmd->cmd, bl_cmd->tx_len);
-	do {
+		dell_uart_write(uart, bl_cmd->cmd, bl_cmd->tx_len);
+		msleep(100);
 		rx_len = dell_uart_read(uart, bl_cmd->ret, bl_cmd->rx_len);
-		if (rx_len == 0)
-			msleep(100);
-	} while (rx_len == 0 && --retry);
 
-	mutex_unlock(&dell_pdata->brightness_mutex);
+		mutex_unlock(&dell_pdata->brightness_mutex);
 
-	dell_uart_dump_cmd(__func__, "rx: ", bl_cmd->ret, rx_len);
+		dell_uart_dump_cmd(__func__, "rx: ", bl_cmd->ret, rx_len);
+	} while (rx_len == 0 && --retry);
 
 	if (rx_len == 4)
 		status = (unsigned int)bl_cmd->ret[2];
-- 
2.17.1