From: Linus Walleij <linus.wall...@linaro.org>
[ Upstream commit 1f20bf5921de420071fdb1d55cda7550ae137bcd ]
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 <step...@gerhold.net>
Fixes: 9c3f0a0dd6a1 ("drm/panel: s6e63m0: Implement 28 backlight levels")
Signed-off-by: Linus Walleij <linus.wall...@linaro.org>
Reviewed-by: Sam Ravnborg <s...@ravnborg.org>
Link:
https://patchwork.freedesktop.org/patch/msgid/20201214222210.238081-1-linus.wall...@linaro.org
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
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 bf6d704d4d272..603c5dfe87682 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;
--
2.27.0
