Hi Linus. On Mon, Dec 14, 2020 at 11:22:10PM +0100, Linus Walleij wrote:

The "max-brightness" is a standard backlight property that we need to support for the Samsung GT-I8190 Golden because the display will go black if we crank up the brightness too high.

As the platform needs this ability to give picture this is a regression fix along with the addition of the property to the GT-I8190 device tree.

Cc: Stephan Gerhold stephan@gerhold.net Fixes: 9c3f0a0dd6a1 ("drm/panel: s6e63m0: Implement 28 backlight levels") Signed-off-by: Linus Walleij linus.walleij@linaro.org

Looks good. backlight_properties.max_brightness is an int, but this looks like a sub-optimal type so the use of u32 in this patch is fine.

Reviewed-by: Sam Ravnborg sam@ravnborg.org

As we are in the merge window it should be drm-next-fixes material, but you may have to wait until -rc2 before the drm-next-fixes branched is ready.

Sam

---

drivers/gpu/drm/panel/panel-samsung-s6e63m0.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c index bf6d704d4d27..603c5dfe8768 100644 --- a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c +++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c @@ -692,12 +692,12 @@ static const struct backlight_ops s6e63m0_backlight_ops = { .update_status = s6e63m0_set_brightness, };

-static int s6e63m0_backlight_register(struct s6e63m0 *ctx) +static int s6e63m0_backlight_register(struct s6e63m0 *ctx, u32 max_brightness) { struct backlight_properties props = { .type = BACKLIGHT_RAW,

• .brightness	= MAX_BRIGHTNESS,
  

• .max_brightness = MAX_BRIGHTNESS
  

• .brightness	= max_brightness,
  

• .max_brightness = max_brightness,
  

  }; struct device *dev = ctx->dev; int ret = 0;

@@ -719,6 +719,7 @@ int s6e63m0_probe(struct device *dev, bool dsi_mode) { struct s6e63m0 *ctx;

• u32 max_brightness; int ret;

  ctx = devm_kzalloc(dev, sizeof(struct s6e63m0), GFP_KERNEL);

@@ -734,6 +735,14 @@ int s6e63m0_probe(struct device *dev, ctx->enabled = false; ctx->prepared = false;

• ret = device_property_read_u32(dev, "max-brightness", &max_brightness);
• if (ret)

• max_brightness = MAX_BRIGHTNESS;
  

• if (max_brightness > MAX_BRIGHTNESS) {

• dev_err(dev, "illegal max brightness specified\n");
  

• max_brightness = MAX_BRIGHTNESS;
  

• }
• ctx->supplies[0].supply = "vdd3"; ctx->supplies[1].supply = "vci"; ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ctx->supplies),

@@ -753,7 +762,7 @@ int s6e63m0_probe(struct device *dev, dsi_mode ? DRM_MODE_CONNECTOR_DSI : DRM_MODE_CONNECTOR_DPI);

• ret = s6e63m0_backlight_register(ctx);

• ret = s6e63m0_backlight_register(ctx, max_brightness); if (ret < 0) return ret;

-- 2.29.2