# \[PATCH AUTOSEL 4.14 27/33\] backlight: lm3630a: Fix return code of .update\_status() callback

- From: Sasha Levin \<sashal@kernel.org\>
- Date: 2021-07-10 02:37:48 
- List: linux-fbdev
- Page: https://ratatoskr.run/linux-fbdev/2021/07/1438139
- Thread: https://ratatoskr.run/stable/2021/07/1438182/t.md

```text
From: Uwe Kleine-König <redacted>

[ Upstream commit b9481a667a90ec739995e85f91f3672ca44d6ffa ]

According to <linux/backlight.h> .update_status() is supposed to
return 0 on success and a negative error code otherwise. Adapt
lm3630a_bank_a_update_status() and lm3630a_bank_b_update_status() to
actually do it.

While touching that also add the error code to the failure message.

Signed-off-by: Uwe Kleine-König <redacted>
Reviewed-by: Daniel Thompson <redacted>
Signed-off-by: Lee Jones <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/video/backlight/lm3630a_bl.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/video/backlight/lm3630a_bl.c b/drivers/video/backlight/lm3630a_bl.c
index ef2553f452ca..f17e5a8860fa 100644
--- a/drivers/video/backlight/lm3630a_bl.c
+++ b/drivers/video/backlight/lm3630a_bl.c
@@ -184,7 +184,7 @@ static int lm3630a_bank_a_update_status(struct backlight_device *bl)
 	if ((pwm_ctrl & LM3630A_PWM_BANK_A) != 0) {
 		lm3630a_pwm_ctrl(pchip, bl->props.brightness,
 				 bl->props.max_brightness);
-		return bl->props.brightness;
+		return 0;
 	}
 
 	/* disable sleep */
@@ -204,8 +204,8 @@ static int lm3630a_bank_a_update_status(struct backlight_device *bl)
 	return 0;
 
 out_i2c_err:
-	dev_err(pchip->dev, "i2c failed to access\n");
-	return bl->props.brightness;
+	dev_err(pchip->dev, "i2c failed to access (%pe)\n", ERR_PTR(ret));
+	return ret;
 }
 
 static int lm3630a_bank_a_get_brightness(struct backlight_device *bl)
@@ -261,7 +261,7 @@ static int lm3630a_bank_b_update_status(struct backlight_device *bl)
 	if ((pwm_ctrl & LM3630A_PWM_BANK_B) != 0) {
 		lm3630a_pwm_ctrl(pchip, bl->props.brightness,
 				 bl->props.max_brightness);
-		return bl->props.brightness;
+		return 0;
 	}
 
 	/* disable sleep */
@@ -281,8 +281,8 @@ static int lm3630a_bank_b_update_status(struct backlight_device *bl)
 	return 0;
 
 out_i2c_err:
-	dev_err(pchip->dev, "i2c failed to access REG_CTRL\n");
-	return bl->props.brightness;
+	dev_err(pchip->dev, "i2c failed to access (%pe)\n", ERR_PTR(ret));
+	return ret;
 }
 
 static int lm3630a_bank_b_get_brightness(struct backlight_device *bl)
-- 
2.30.2

```