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