From 125459e19ec654924e472f3ff5aeea40358dbebf Mon Sep 17 00:00:00 2001 From: Brigham Campbell Date: Wed, 30 Jul 2025 21:23:41 -0600 Subject: [PATCH] drm/panel: novatek-nt35560: Fix invalid return value Fix bug in nt35560_set_brightness() which causes the function to erroneously report an error. mipi_dsi_dcs_write() returns either a negative value when an error occurred or a positive number of bytes written when no error occurred. The buggy code reports an error under either condition. Fixes: 8152c2bfd780 ("drm/panel: Add driver for Sony ACX424AKP panel") Reviewed-by: Douglas Anderson Reviewed-by: Neil Armstrong Signed-off-by: Brigham Campbell Signed-off-by: Neil Armstrong Link: https://lore.kernel.org/r/20250731032343.1258366-2-me@brighamcampbell.com --- drivers/gpu/drm/panel/panel-novatek-nt35560.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/panel/panel-novatek-nt35560.c b/drivers/gpu/drm/panel/panel-novatek-nt35560.c index 98f0782c84111..17898a29efe87 100644 --- a/drivers/gpu/drm/panel/panel-novatek-nt35560.c +++ b/drivers/gpu/drm/panel/panel-novatek-nt35560.c @@ -161,7 +161,7 @@ static int nt35560_set_brightness(struct backlight_device *bl) par = 0x00; ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY, &par, 1); - if (ret) { + if (ret < 0) { dev_err(nt->dev, "failed to disable display backlight (%d)\n", ret); return ret; } -- 2.47.3