| Message ID | 57a8498440695218d095cb037a5dc818d6fe7355.1729630039.git.jahau@rocketmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add new panel driver Samsung S6E88A0-AMS427AP24 | expand |
On 22/10/2024 23:33, Jakob Hauser wrote: > The way of implementing a flip option follows the existing > panel-samsung-s6e8aa0.c [1][2][3]. > > The value to flip the screen is taken from a downstream kernel file of > a similar but older panel [4]. The mipi clock [5] for the new panel > samsung-s6e88a0-ams427ap24 matches 461 MHz and a hardware read-out of the > 0xcb values corresponds to revision R01 of that older panel [6]. Although > for samsung-s6e88a0-ams427ap24 that's in non-flipped state while in this > older driver it seems to be the other way around. Further up there is a > hint [7] basically saying for revision R01 to change the first word of the > 0xcb command from 0x06 to 0x0e, which is actually setting BIT(3) of that > word. This causes a horizontal flip. > > [1] https://github.com/torvalds/linux/blob/v6.11/drivers/gpu/drm/panel/panel-samsung-s6e8aa0.c#L103 > [2] https://github.com/torvalds/linux/blob/v6.11/drivers/gpu/drm/panel/panel-samsung-s6e8aa0.c#L207-L211 > [3] https://github.com/torvalds/linux/blob/v6.11/drivers/gpu/drm/panel/panel-samsung-s6e8aa0.c#L954-L974 > [4] https://github.com/LineageOS/android_kernel_samsung_msm8930-common/blob/lineage-15.1/drivers/video/msm/mipi_samsung_oled_video_qhd_pt-8930.c > [5] https://github.com/LineageOS/android_kernel_samsung_msm8930-common/blob/lineage-15.1/drivers/video/msm/mipi_samsung_oled_video_qhd_pt-8930.c#L2027-L2028 > [6] https://github.com/LineageOS/android_kernel_samsung_msm8930-common/blob/lineage-15.1/drivers/video/msm/mipi_samsung_oled_video_qhd_pt-8930.c#L137-L151 > [7] https://github.com/LineageOS/android_kernel_samsung_msm8930-common/blob/lineage-15.1/drivers/video/msm/mipi_samsung_oled_video_qhd_pt-8930.c#L66-L74 > > Signed-off-by: Jakob Hauser <jahau@rocketmail.com> > --- > .../drm/panel/panel-samsung-s6e88a0-ams427ap24.c | 16 ++++++++++++++++ > 1 file changed, 16 insertions(+) > > diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e88a0-ams427ap24.c b/drivers/gpu/drm/panel/panel-samsung-s6e88a0-ams427ap24.c > index 6e02b881434d..8372d0d307c8 100644 > --- a/drivers/gpu/drm/panel/panel-samsung-s6e88a0-ams427ap24.c > +++ b/drivers/gpu/drm/panel/panel-samsung-s6e88a0-ams427ap24.c > @@ -32,6 +32,7 @@ struct s6e88a0_ams427ap24 { > struct mipi_dsi_device *dsi; > struct regulator_bulk_data *supplies; > struct gpio_desc *reset_gpio; > + bool flip_horizontal; > }; > > const struct regulator_bulk_data s6e88a0_ams427ap24_supplies[] = { > @@ -538,6 +539,10 @@ static int s6e88a0_ams427ap24_on(struct s6e88a0_ams427ap24 *ctx) > mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xcc, 0x4c); > mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf2, 0x03, 0x0d); > mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf1, 0xa5, 0xa5); > + > + if (ctx->flip_horizontal) > + mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xcb, 0x0e); > + > mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf0, 0xa5, 0xa5); > mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfc, 0xa5, 0xa5); > > @@ -672,6 +677,15 @@ static int s6e88a0_ams427ap24_register_backlight(struct s6e88a0_ams427ap24 *ctx) > return ret; > } > > +static void s6e88a0_ams427ap24_parse_dt(struct s6e88a0_ams427ap24 *ctx) > +{ > + struct mipi_dsi_device *dsi = ctx->dsi; > + struct device *dev = &dsi->dev; > + struct device_node *np = dev->of_node; > + > + ctx->flip_horizontal = of_property_read_bool(np, "flip-horizontal"); Please use device_property_read_bool() instead > +} > + > static int s6e88a0_ams427ap24_probe(struct mipi_dsi_device *dsi) > { > struct device *dev = &dsi->dev; > @@ -706,6 +720,8 @@ static int s6e88a0_ams427ap24_probe(struct mipi_dsi_device *dsi) > DRM_MODE_CONNECTOR_DSI); > ctx->panel.prepare_prev_first = true; > > + s6e88a0_ams427ap24_parse_dt(ctx); I don't think this deserves a separate function, just move it probe. > + > ret = s6e88a0_ams427ap24_register_backlight(ctx); > if (ret < 0) > return ret; With that changed: Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e88a0-ams427ap24.c b/drivers/gpu/drm/panel/panel-samsung-s6e88a0-ams427ap24.c index 6e02b881434d..8372d0d307c8 100644 --- a/drivers/gpu/drm/panel/panel-samsung-s6e88a0-ams427ap24.c +++ b/drivers/gpu/drm/panel/panel-samsung-s6e88a0-ams427ap24.c @@ -32,6 +32,7 @@ struct s6e88a0_ams427ap24 { struct mipi_dsi_device *dsi; struct regulator_bulk_data *supplies; struct gpio_desc *reset_gpio; + bool flip_horizontal; }; const struct regulator_bulk_data s6e88a0_ams427ap24_supplies[] = { @@ -538,6 +539,10 @@ static int s6e88a0_ams427ap24_on(struct s6e88a0_ams427ap24 *ctx) mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xcc, 0x4c); mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf2, 0x03, 0x0d); mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf1, 0xa5, 0xa5); + + if (ctx->flip_horizontal) + mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xcb, 0x0e); + mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf0, 0xa5, 0xa5); mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfc, 0xa5, 0xa5); @@ -672,6 +677,15 @@ static int s6e88a0_ams427ap24_register_backlight(struct s6e88a0_ams427ap24 *ctx) return ret; } +static void s6e88a0_ams427ap24_parse_dt(struct s6e88a0_ams427ap24 *ctx) +{ + struct mipi_dsi_device *dsi = ctx->dsi; + struct device *dev = &dsi->dev; + struct device_node *np = dev->of_node; + + ctx->flip_horizontal = of_property_read_bool(np, "flip-horizontal"); +} + static int s6e88a0_ams427ap24_probe(struct mipi_dsi_device *dsi) { struct device *dev = &dsi->dev; @@ -706,6 +720,8 @@ static int s6e88a0_ams427ap24_probe(struct mipi_dsi_device *dsi) DRM_MODE_CONNECTOR_DSI); ctx->panel.prepare_prev_first = true; + s6e88a0_ams427ap24_parse_dt(ctx); + ret = s6e88a0_ams427ap24_register_backlight(ctx); if (ret < 0) return ret;
The way of implementing a flip option follows the existing panel-samsung-s6e8aa0.c [1][2][3]. The value to flip the screen is taken from a downstream kernel file of a similar but older panel [4]. The mipi clock [5] for the new panel samsung-s6e88a0-ams427ap24 matches 461 MHz and a hardware read-out of the 0xcb values corresponds to revision R01 of that older panel [6]. Although for samsung-s6e88a0-ams427ap24 that's in non-flipped state while in this older driver it seems to be the other way around. Further up there is a hint [7] basically saying for revision R01 to change the first word of the 0xcb command from 0x06 to 0x0e, which is actually setting BIT(3) of that word. This causes a horizontal flip. [1] https://github.com/torvalds/linux/blob/v6.11/drivers/gpu/drm/panel/panel-samsung-s6e8aa0.c#L103 [2] https://github.com/torvalds/linux/blob/v6.11/drivers/gpu/drm/panel/panel-samsung-s6e8aa0.c#L207-L211 [3] https://github.com/torvalds/linux/blob/v6.11/drivers/gpu/drm/panel/panel-samsung-s6e8aa0.c#L954-L974 [4] https://github.com/LineageOS/android_kernel_samsung_msm8930-common/blob/lineage-15.1/drivers/video/msm/mipi_samsung_oled_video_qhd_pt-8930.c [5] https://github.com/LineageOS/android_kernel_samsung_msm8930-common/blob/lineage-15.1/drivers/video/msm/mipi_samsung_oled_video_qhd_pt-8930.c#L2027-L2028 [6] https://github.com/LineageOS/android_kernel_samsung_msm8930-common/blob/lineage-15.1/drivers/video/msm/mipi_samsung_oled_video_qhd_pt-8930.c#L137-L151 [7] https://github.com/LineageOS/android_kernel_samsung_msm8930-common/blob/lineage-15.1/drivers/video/msm/mipi_samsung_oled_video_qhd_pt-8930.c#L66-L74 Signed-off-by: Jakob Hauser <jahau@rocketmail.com> --- .../drm/panel/panel-samsung-s6e88a0-ams427ap24.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)