Re: [PATCH v2 2/3] drm: panel: Add Samsung S6E8FCO
From: David Heidelberg
Date: Mon Feb 23 2026 - 17:00:45 EST
On 23/02/2026 21:26, Yedaya Katsman wrote:
Add driver for Samsung S6E8FCO DSI video mode panel, used in
Xiaomi Mi A3 mobile phone.
Co-developed-by: Kamil Gołda <kamil.golda@xxxxxxxxxxxxxx>
Signed-off-by: Kamil Gołda <kamil.golda@xxxxxxxxxxxxxx>
Signed-off-by: Yedaya Katsman <yedaya.ka@xxxxxxxxx>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
---
MAINTAINERS | 1 +
drivers/gpu/drm/panel/Kconfig | 12 ++
drivers/gpu/drm/panel/Makefile | 1 +
drivers/gpu/drm/panel/panel-samsung-s6e8fco.c | 293 ++++++++++++++++++++++++++
4 files changed, 307 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 545d4cf68b9ac27765c7981e668e32cfecf3366b..238b5332eaf0e0cfb9834084e24671ccaee79939 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8187,6 +8187,7 @@ DRM DRIVER FOR SAMSUNG S6E8FCO PANELS
M: Yedaya Katsman <yedaya.ka@xxxxxxxxx>
S: Maintained
F: Documentation/devicetree/bindings/display/panel/samsung,s6e8fco.yaml
+F: drivers/gpu/drm/panel/panel-samsung-s6e8fco.c
DRM DRIVER FOR SAMSUNG SOFEF00 DDIC
M: David Heidelberg <david@xxxxxxx>
diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 7a83804fedca1b688ce6fbe4295ec9009007e693..734640bb3f73c83e9273573aeb720ea1ba20862f 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -893,6 +893,18 @@ config DRM_PANEL_SAMSUNG_S6E8AA5X01_AMS561RA01
~5.6 inch AMOLED display, and the controller is driven by the MIPI
DSI protocol with 4 lanes.
+config DRM_PANEL_SAMSUNG_S6E8FCO
+ tristate "Samsung S6E8FCO DSI video mode panel"
+ depends on OF
+ depends on BACKLIGHT_CLASS_DEVICE
+ select DRM_MIPI_DSI
+ select VIDEOMODE_HELPERS
+ help
+ Say Y or M here if you want to enable support for the Samsung video
+ mode panel S6E8FCO. The panel has a 6.09 inch AMOLED display, with
The S6E8.. is not panel, but Display Driver IC, the panel from the replacement parts is likely one of M1906F9SH M1906F9SI, thus I would say M1906F9.
+ a resolution of 720x1560.
+ Found in the Xiaomi Mi A3 smartphone (xiaomi-laurel).
+
config DRM_PANEL_SAMSUNG_SOFEF00
tristate "Samsung SOFEF00 DSI panel controller"
depends on OF
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index b9562a6fdcb38bfd0dfee9e8c11e16149ada4386..54eca60e5b57328ea94ed7880f4dead981f87fc1 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -91,6 +91,7 @@ obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E88A0_AMS427AP24) += panel-samsung-s6e88a0-ams4
obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E88A0_AMS452EF01) += panel-samsung-s6e88a0-ams452ef01.o
obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E8AA0) += panel-samsung-s6e8aa0.o
obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E8AA5X01_AMS561RA01) += panel-samsung-s6e8aa5x01-ams561ra01.o
+obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E8FCO) += panel-samsung-s6e8fco.o
obj-$(CONFIG_DRM_PANEL_SAMSUNG_SOFEF00) += panel-samsung-sofef00.o
obj-$(CONFIG_DRM_PANEL_SEIKO_43WVF1G) += panel-seiko-43wvf1g.o
obj-$(CONFIG_DRM_PANEL_SHARP_LQ079L1SX01) += panel-sharp-lq079l1sx01.o
diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e8fco.c b/drivers/gpu/drm/panel/panel-samsung-s6e8fco.c
new file mode 100644
index 0000000000000000000000000000000000000000..7bbbe8af3e2eb9021ed7f555cb4ad2b0d7ea55ee
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-samsung-s6e8fco.c
@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (c) 2025 Kamil Gołda <kamil.golda@xxxxxxxxxxxxxx>
nitpick: you can also drop copyright year from your copyright or update, up to you.
+// Generated with linux-mdss-dsi-panel-driver-generator from vendor device tree:
+// Copyright (c) 2025, The Linux Foundation. All rights reserved.
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+
+#include <video/mipi_display.h>
+
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_probe_helper.h>
+
+struct s6e8fco_samsungp {
+ struct drm_panel panel;
+ struct mipi_dsi_device *dsi;
+ struct regulator_bulk_data *supplies;
+ struct gpio_desc *reset_gpio;
+};
+
+static const struct regulator_bulk_data s6e8fco_samsungp_supplies[] = {
+ { .supply = "vddio" },
+ { .supply = "ldo" },
+ { .supply = "iovcc" },
+};
+
+static inline
+struct s6e8fco_samsungp *to_s6e8fco_samsungp(struct drm_panel *panel)
+{
+ return container_of_const(panel, struct s6e8fco_samsungp, panel);
+}
+
+static void s6e8fco_samsungp_reset(struct s6e8fco_samsungp *ctx)
+{
+ gpiod_set_value_cansleep(ctx->reset_gpio, 0);
+ usleep_range(12000, 13000);
+ gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+ usleep_range(2000, 3000);
+ gpiod_set_value_cansleep(ctx->reset_gpio, 0);
+ usleep_range(10000, 11000);
+}
+
+static int s6e8fco_samsungp_on(struct s6e8fco_samsungp *ctx)
+{
+ struct mipi_dsi_multi_context dsi_ctx = { .dsi = ctx->dsi };
+
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfc, 0x5a, 0x5a);
#define s6e3fc2x01_test_key_on_lvl3(ctx) \
mipi_dsi_dcs_write_seq_multi(ctx, 0xfc, 0x5a, 0x5a> +
+ mipi_dsi_dcs_set_display_brightness_multi(&dsi_ctx, 0x0000);
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, MIPI_DCS_WRITE_CONTROL_DISPLAY,
+ 0x20);
+ mipi_dsi_dcs_exit_sleep_mode_multi(&dsi_ctx);
+ mipi_dsi_msleep(&dsi_ctx, 50);
+ mipi_dsi_dcs_set_display_on_multi(&dsi_ctx);
+
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xb0, 0x04, 0xed);
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xed,
+ 0xe4, 0x08, 0x96, 0xa4, 0x2a, 0x72, 0xe2,
+ 0xca, 0x00);
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfc, 0xa5, 0xa5);
#define s6e3fc2x01_test_key_off_lvl3(ctx) \
mipi_dsi_dcs_write_seq_multi(ctx, 0xfc, 0xa5, 0xa5)
etc. etc., check panel-samsung-s6e3fc2x01.c for example (and eventually other surrounding drivers) and try to de-mystify the writes as much as you can (ofc "reasonably" - as we don't have the datasheet).
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf0, 0x5a, 0x5a);
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfc, 0x5a, 0x5a);
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xe1, 0x93);
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xb0, 0x05, 0xf4);
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf4, 0x03);
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xed, 0x01, 0x81, 0x04);
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf0, 0xa5, 0xa5);
+ mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfc, 0xa5, 0xa5);
+
+ return dsi_ctx.accum_err;
+}
+
+static int s6e8fco_samsungp_off(struct s6e8fco_samsungp *ctx)
+{
+ struct mipi_dsi_multi_context dsi_ctx = { .dsi = ctx->dsi };
+
+
+ mipi_dsi_dcs_set_display_off_multi(&dsi_ctx);
+ mipi_dsi_msleep(&dsi_ctx, 20);
+ mipi_dsi_dcs_enter_sleep_mode_multi(&dsi_ctx);
+ mipi_dsi_msleep(&dsi_ctx, 120);
+
+ return dsi_ctx.accum_err;
+}
+
+static int s6e8fco_samsungp_prepare(struct drm_panel *panel)
+{
+ struct s6e8fco_samsungp *ctx = to_s6e8fco_samsungp(panel);
+ struct device *dev = &ctx->dsi->dev;
+ int ret;
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(s6e8fco_samsungp_supplies), ctx->supplies);
+ if (ret < 0) {
+ dev_err(dev, "Failed to enable regulators: %d\n", ret);
+ return ret;
+ }
+
+ s6e8fco_samsungp_reset(ctx);
+
+ ret = s6e8fco_samsungp_on(ctx);
+ if (ret < 0) {
+ dev_err(dev, "Failed to initialize panel: %d\n", ret);
+ gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+ regulator_bulk_disable(ARRAY_SIZE(s6e8fco_samsungp_supplies), ctx->supplies);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int s6e8fco_samsungp_unprepare(struct drm_panel *panel)
+{
+ struct s6e8fco_samsungp *ctx = to_s6e8fco_samsungp(panel);
+ struct device *dev = &ctx->dsi->dev;
+ int ret;
+
+ ret = s6e8fco_samsungp_off(ctx);
+ if (ret < 0)
+ dev_err(dev, "Failed to un-initialize panel: %d\n", ret);
+
+ gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+ regulator_bulk_disable(ARRAY_SIZE(s6e8fco_samsungp_supplies), ctx->supplies);
+
+ return 0;
+}
+
+static const struct drm_display_mode s6e8fco_samsungp_mode = {
name the struct according to the panel, not (only) the DDIC.
+ .clock = (720 + 350 + 40 + 294) * (1560 + 17 + 2 + 5) * 60 / 1000,
+ .hdisplay = 720,
+ .hsync_start = 720 + 350,
+ .hsync_end = 720 + 350 + 40,
+ .htotal = 720 + 350 + 40 + 294,
+ .vdisplay = 1560,
+ .vsync_start = 1560 + 17,
+ .vsync_end = 1560 + 17 + 2,
+ .vtotal = 1560 + 17 + 2 + 5,
+ .width_mm = 65,
+ .height_mm = 140,
+ .type = DRM_MODE_TYPE_DRIVER,
+};
+
+static int s6e8fco_samsungp_get_modes(struct drm_panel *panel,
+ struct drm_connector *connector)
+{
+ return drm_connector_helper_get_modes_fixed(connector, &s6e8fco_samsungp_mode);
+}
+
+static const struct drm_panel_funcs s6e8fco_samsungp_panel_funcs = {
+ .prepare = s6e8fco_samsungp_prepare,
+ .unprepare = s6e8fco_samsungp_unprepare,
+ .get_modes = s6e8fco_samsungp_get_modes,
+};
+
+static int s6e8fco_samsungp_bl_update_status(struct backlight_device *bl)
+{
+ struct mipi_dsi_device *dsi = bl_get_data(bl);
+ u16 brightness = backlight_get_brightness(bl);
+ int ret;
+
+ dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
+
+ ret = mipi_dsi_dcs_set_display_brightness_large(dsi, brightness);
+ if (ret < 0)
+ return ret;
+
+ dsi->mode_flags |= MIPI_DSI_MODE_LPM;
+
+ return 0;
+}
+
+static int s6e8fco_samsungp_bl_get_brightness(struct backlight_device *bl)
+{
+ struct mipi_dsi_device *dsi = bl_get_data(bl);
+ u16 brightness;
+ int ret;
+
+ dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
+
+ ret = mipi_dsi_dcs_get_display_brightness_large(dsi, &brightness);
+ if (ret < 0)
+ return ret;
+
+ dsi->mode_flags |= MIPI_DSI_MODE_LPM;
+
+ return brightness;
+}
+
+static const struct backlight_ops s6e8fco_samsungp_bl_ops = {
+ .update_status = s6e8fco_samsungp_bl_update_status,
+ .get_brightness = s6e8fco_samsungp_bl_get_brightness,
+};
+
+static struct backlight_device *
+s6e8fco_samsungp_create_backlight(struct mipi_dsi_device *dsi)
+{
+ struct device *dev = &dsi->dev;
+ const struct backlight_properties props = {
+ .type = BACKLIGHT_RAW,
+ .brightness = 268,
~ 10% of brightness at boot? What is the scale? Shouldn't make sense to set it around 50%? (just asking)
+ .max_brightness = 2047,
+ };
+
+ return devm_backlight_device_register(dev, dev_name(dev), dev, dsi,
+ &s6e8fco_samsungp_bl_ops, &props);
+}
+
+static int s6e8fco_samsungp_probe(struct mipi_dsi_device *dsi)
+{
+ struct device *dev = &dsi->dev;
+ struct s6e8fco_samsungp *ctx;
+ int ret;
+
+ ctx = devm_drm_panel_alloc(dev, struct s6e8fco_samsungp, panel,
+ &s6e8fco_samsungp_panel_funcs,
+ DRM_MODE_CONNECTOR_DSI);
+ if (IS_ERR(ctx))
+ return PTR_ERR(ctx);
+
+ ret = devm_regulator_bulk_get_const(dev,
+ ARRAY_SIZE(s6e8fco_samsungp_supplies),
+ s6e8fco_samsungp_supplies,
+ &ctx->supplies);
+ if (ret < 0)
+ return ret;
+
+ ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(ctx->reset_gpio))
+ return dev_err_probe(dev, PTR_ERR(ctx->reset_gpio),
+ "Failed to get reset-gpios\n");
+
+ ctx->dsi = dsi;
+ mipi_dsi_set_drvdata(dsi, ctx);
+
+ dsi->lanes = 4;
+ dsi->format = MIPI_DSI_FMT_RGB888;
+ dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
+ MIPI_DSI_CLOCK_NON_CONTINUOUS;
+
+ ctx->panel.prepare_prev_first = true;
+
+ ctx->panel.backlight = s6e8fco_samsungp_create_backlight(dsi);
+ if (IS_ERR(ctx->panel.backlight))
+ return dev_err_probe(dev, PTR_ERR(ctx->panel.backlight),
+ "Failed to create backlight\n");
+
+ drm_panel_add(&ctx->panel);
+
+ ret = mipi_dsi_attach(dsi);
+ if (ret < 0) {
+ drm_panel_remove(&ctx->panel);
+ return dev_err_probe(dev, ret, "Failed to attach to DSI host\n");
+ }
+
+ return 0;
+}
+
+static void s6e8fco_samsungp_remove(struct mipi_dsi_device *dsi)
+{
+ struct s6e8fco_samsungp *ctx = mipi_dsi_get_drvdata(dsi);
+ int ret;
+
+ ret = mipi_dsi_detach(dsi);
+ if (ret < 0)
+ dev_err(&dsi->dev, "Failed to detach from DSI host: %d\n", ret);
+
+ drm_panel_remove(&ctx->panel);
+}
+
+static const struct of_device_id s6e8fco_samsungp_of_match[] = {
+ { .compatible = "samsung,s6e8fco" },
Optimally the compatible should reflect the panel used, eg something like samsung,s6e8fco-m1906f9 . It's possible there will be more panels using this DDIC, then this would make it much clearer.
Happy to see another phone panel heading to mainline, thanks for your work!
David
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, s6e8fco_samsungp_of_match);
+
+static struct mipi_dsi_driver s6e8fco_samsungp_driver = {
+ .probe = s6e8fco_samsungp_probe,
+ .remove = s6e8fco_samsungp_remove,
+ .driver = {
+ .name = "panel-samsung-s6e8fco",
+ .of_match_table = s6e8fco_samsungp_of_match,
+ },
+};
+module_mipi_dsi_driver(s6e8fco_samsungp_driver);
+
+MODULE_AUTHOR("Kamil Gołda <kamil.golda@xxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("DRM driver for s6e8fco samsung amoled video mode dsi panel");
+MODULE_LICENSE("GPL");
--
David Heidelberg