[PATCH v2 0/2] gpu/drm: panel: add support for DSI panel used in Motorola Atrix 4G and Droid X2

[PATCH v2 0/2] gpu/drm: panel: add support for DSI panel used in Motorola Atrix 4G and Droid X2

[Svyatoslav Ryhel]

Add support for the DSI LCD panel module found in Motorola Atrix 4G or
Droid X2 smartphones. Exact panel vendor and model are unknown hence panel
uses generic compatible based on board where it is used. The panel has a
540x960 resolution with 24 bit RGB per pixel.

---
Changes in v2:
- updated schema commit description
---

Svyatoslav Ryhel (2):
  dt-bindings: display: panel: document Atrix 4G and Droid X2 DSI panel
  gpu/drm: panel: add support for DSI panel used in Motorola Atrix 4G
    and Droid X2

 .../display/panel/motorola,mot-panel.yaml     |  69 +++++
 drivers/gpu/drm/panel/Kconfig                 |  12 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 drivers/gpu/drm/panel/panel-motorola-mot.c    | 244 ++++++++++++++++++
 4 files changed, 326 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/motorola,mot-panel.yaml
 create mode 100644 drivers/gpu/drm/panel/panel-motorola-mot.c

-- 
2.51.0

[PATCH v2 1/2] dt-bindings: display: panel: document Atrix 4G and Droid X2 DSI panel

[Svyatoslav Ryhel]

Atrix 4G and Droid X2 are based on a board called by Motorola "Mot" and
use the same 540x960 DSI video mode panel. Exact panel vendor and model
are unknown hence generic compatible based on board name "Mot" is used.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
---
 .../display/panel/motorola,mot-panel.yaml     | 69 +++++++++++++++++++
 1 file changed, 69 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/motorola,mot-panel.yaml

diff --git a/Documentation/devicetree/bindings/display/panel/motorola,mot-panel.yaml b/Documentation/devicetree/bindings/display/panel/motorola,mot-panel.yaml
new file mode 100644
index 000000000000..99fa1b3ed426
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/panel/motorola,mot-panel.yaml
@@ -0,0 +1,69 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/motorola,mot-panel.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Atrix 4G and Droid X2 DSI Display Panel
+
+maintainers:
+  - Svyatoslav Ryhel <clamor95@gmail.com>
+
+description:
+  Atrix 4G and Droid X2 use the same 540x960 DSI video mode panel. Exact
+  panel vendor and model are unknown hence generic compatible based on the
+  board name "Mot" is used.
+
+allOf:
+  - $ref: panel-common.yaml#
+
+properties:
+  compatible:
+    items:
+      - const: motorola,mot-panel
+
+  reg:
+    maxItems: 1
+
+  vdd-supply:
+    description: Regulator for main power supply.
+
+  vddio-supply:
+    description: Regulator for 1.8V IO power supply.
+
+  backlight: true
+  reset-gpios: true
+  port: true
+
+required:
+  - compatible
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    dsi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        panel@0 {
+            compatible = "motorola,mot-panel";
+            reg = <0>;
+
+            reset-gpios = <&gpio 35 GPIO_ACTIVE_LOW>;
+
+            vdd-supply = <&vdd_5v0_panel>;
+            vddio-supply = <&vdd_1v8_vio>;
+
+            backlight = <&backlight>;
+
+            port {
+                panel_in: endpoint {
+                    remote-endpoint = <&dsi_out>;
+                };
+            };
+        };
+    };
+...
-- 
2.51.0

Claude review: dt-bindings: display: panel: document Atrix 4G and Droid X2 DSI panel

[Claude Code Review Bot]

Patch Review

The binding looks straightforward. A few observations:

> +properties:
> +  compatible:
> +    items:
> +      - const: motorola,mot-panel

Using `items` with a single `const` works but could be simplified to just `const: motorola,mot-panel`. Either form is valid.

> +  vdd-supply:
> +    description: Regulator for main power supply.
> +
> +  vddio-supply:
> +    description: Regulator for 1.8V IO power supply.
> +
> +  backlight: true
> +  reset-gpios: true
> +  port: true
> +
> +required:
> +  - compatible

The `reg` property is not in `required`. For a DSI panel, `reg` specifies the virtual channel and is typically needed. The example does include it, so this is just a schema completeness question -- DT binding maintainers may or may not care since the DSI bus binding may enforce it separately.

No other issues found with this patch.

---
Generated by Claude Code Patch Reviewer

[PATCH v2 2/2] gpu/drm: panel: add support for DSI panel used in Motorola Atrix 4G and Droid X2

[Svyatoslav Ryhel]

Add support for the DSI LCD panel module found in Motorola Atrix 4G or
Droid X2 smartphones. Exact panel vendor and model are unknown hence panel
uses generic compatible based on board where it is used. The panel has a
540x960 resolution with 24 bit RGB per pixel.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
---
 drivers/gpu/drm/panel/Kconfig              |  12 +
 drivers/gpu/drm/panel/Makefile             |   1 +
 drivers/gpu/drm/panel/panel-motorola-mot.c | 244 +++++++++++++++++++++
 3 files changed, 257 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-motorola-mot.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 307152ad7759..477c54c90b01 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -464,6 +464,18 @@ config DRM_PANEL_MANTIX_MLAF057WE51
 	  has a resolution of 720x1440 pixels, a built in backlight and touch
 	  controller.
 
+config DRM_PANEL_MOTOROLA_MOT
+	tristate "Atrix 4G and Droid X2 540x960 DSI video mode panel"
+	depends on OF
+	depends on DRM_MIPI_DSI
+	depends on BACKLIGHT_CLASS_DEVICE
+	select VIDEOMODE_HELPERS
+	help
+	  Say Y here if you want to enable support for the LCD panel module
+	  for Motorola Atrix 4G or Droid X2. Exact panel vendor and model are
+	  unknown. The panel has a 540x960 resolution and uses 24 bit RGB per
+	  pixel.
+
 config DRM_PANEL_NEC_NL8048HL11
 	tristate "NEC NL8048HL11 RGB panel"
 	depends on GPIOLIB && OF && SPI
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index aeffaa95666d..e17ef8140806 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -45,6 +45,7 @@ obj-$(CONFIG_DRM_PANEL_LG_LD070WX3) += panel-lg-ld070wx3.o
 obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o
 obj-$(CONFIG_DRM_PANEL_LG_SW43408) += panel-lg-sw43408.o
 obj-$(CONFIG_DRM_PANEL_MAGNACHIP_D53E6EA8966) += panel-magnachip-d53e6ea8966.o
+obj-$(CONFIG_DRM_PANEL_MOTOROLA_MOT) += panel-motorola-mot.o
 obj-$(CONFIG_DRM_PANEL_NEC_NL8048HL11) += panel-nec-nl8048hl11.o
 obj-$(CONFIG_DRM_PANEL_NEWVISION_NV3051D) += panel-newvision-nv3051d.o
 obj-$(CONFIG_DRM_PANEL_NEWVISION_NV3052C) += panel-newvision-nv3052c.o
diff --git a/drivers/gpu/drm/panel/panel-motorola-mot.c b/drivers/gpu/drm/panel/panel-motorola-mot.c
new file mode 100644
index 000000000000..eb1f86c3d704
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-motorola-mot.c
@@ -0,0 +1,244 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/array_size.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/property.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>
+
+static const struct regulator_bulk_data mot_panel_supplies[] = {
+	{ .supply = "vddio" }, { .supply = "vdd" },
+};
+
+struct mot_panel {
+	struct drm_panel panel;
+	struct mipi_dsi_device *dsi;
+
+	struct gpio_desc *reset_gpio;
+
+	struct regulator_bulk_data *supplies;
+};
+
+static inline struct mot_panel *to_mot_panel(struct drm_panel *panel)
+{
+	return container_of(panel, struct mot_panel, panel);
+}
+
+static void mot_panel_reset(struct mot_panel *priv)
+{
+	gpiod_set_value_cansleep(priv->reset_gpio, 1);
+	usleep_range(50000, 51000);
+	gpiod_set_value_cansleep(priv->reset_gpio, 0);
+	usleep_range(10000, 11000);
+}
+
+static void mot_es2(struct mipi_dsi_multi_context *ctx)
+{
+	mipi_dsi_generic_write_seq_multi(ctx, 0x55, 0x01);
+
+	mipi_dsi_dcs_exit_sleep_mode_multi(ctx);
+	mipi_dsi_msleep(ctx, 120);
+
+	mipi_dsi_generic_write_seq_multi(ctx, 0xf4, 0x00, 0xbb, 0x46, 0x53, 0x0c, 0x49,
+					 0x74, 0x29, 0x12, 0x15, 0x2f, 0x2f, 0x04);
+	mipi_dsi_generic_write_seq_multi(ctx, 0xf8, 0x4b, 0x04, 0x10, 0x1a, 0x2c, 0x2c,
+					 0x2c, 0x2c, 0x14, 0x12);
+
+	mipi_dsi_generic_write_seq_multi(ctx, 0xb5, 0x03, 0x7f, 0x00, 0x80, 0xc7, 0x00);
+	mipi_dsi_generic_write_seq_multi(ctx, 0xb7, 0x66, 0xf6, 0x46, 0x9f, 0x90, 0x99,
+					 0xff, 0x80, 0x6d, 0x01);
+
+	/* Gamma R */
+	mipi_dsi_generic_write_seq_multi(ctx, 0xf9, 0x04);
+	mipi_dsi_generic_write_seq_multi(ctx, 0xfa, 0x00, 0x2f, 0x30, 0x12, 0x0e, 0x0c,
+					 0x22, 0x27, 0x31, 0x2e, 0x07, 0x0f);
+	mipi_dsi_generic_write_seq_multi(ctx, 0xfb, 0x00, 0x2f, 0x30, 0x12, 0x0e, 0x0c,
+					 0x22, 0x27, 0x31, 0x2e, 0x07, 0x0f);
+
+	/* Gamma G */
+	mipi_dsi_generic_write_seq_multi(ctx, 0xf9, 0x02);
+	mipi_dsi_generic_write_seq_multi(ctx, 0xfa, 0x00, 0x2f, 0x37, 0x15, 0x15, 0x11,
+					 0x1f, 0x25, 0x2d, 0x2a, 0x05, 0x0f);
+	mipi_dsi_generic_write_seq_multi(ctx, 0xfb, 0x00, 0x2f, 0x37, 0x15, 0x15, 0x11,
+					 0x1f, 0x25, 0x2d, 0x2a, 0x05, 0x0f);
+
+	/* Gamma B */
+	mipi_dsi_generic_write_seq_multi(ctx, 0xf9, 0x01);
+	mipi_dsi_generic_write_seq_multi(ctx, 0xfa, 0x00, 0x2f, 0x3f, 0x16, 0x1f, 0x15,
+					 0x1f, 0x25, 0x2d, 0x2b, 0x06, 0x0b);
+	mipi_dsi_generic_write_seq_multi(ctx, 0xfb, 0x00, 0x2f, 0x3f, 0x16, 0x1f, 0x15,
+					 0x1f, 0x25, 0x2d, 0x2b, 0x06, 0x0b);
+
+	/* Gamma W */
+	mipi_dsi_generic_write_seq_multi(ctx, 0xf9, 0x20);
+	mipi_dsi_generic_write_seq_multi(ctx, 0xfa, 0x00, 0x2f, 0x34, 0x15, 0x1a, 0x11,
+					 0x1f, 0x23, 0x2d, 0x29, 0x02, 0x08);
+	mipi_dsi_generic_write_seq_multi(ctx, 0xfb, 0x00, 0x2f, 0x34, 0x15, 0x1a, 0x11,
+					 0x1f, 0x23, 0x2d, 0x29, 0x02, 0x08);
+
+	mipi_dsi_generic_write_seq_multi(ctx, 0x53, 0x2c);
+	mipi_dsi_generic_write_seq_multi(ctx, 0x35, 0x00);
+}
+
+static int mot_panel_prepare(struct drm_panel *panel)
+{
+	struct mot_panel *priv = to_mot_panel(panel);
+	struct mipi_dsi_multi_context ctx = { .dsi = priv->dsi };
+	struct device *dev = panel->dev;
+	int ret;
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(mot_panel_supplies), priv->supplies);
+	if (ret < 0) {
+		dev_err(dev, "failed to enable power supplies: %d\n", ret);
+		return ret;
+	}
+
+	mot_panel_reset(priv);
+
+	mipi_dsi_generic_write_seq_multi(&ctx, 0xf0, 0x5a, 0x5a);
+	mipi_dsi_generic_write_seq_multi(&ctx, 0xf1, 0x5a, 0x5a);
+	mipi_dsi_generic_write_seq_multi(&ctx, 0xd0, 0x8e);
+
+	mot_es2(&ctx);
+
+	mipi_dsi_dcs_set_display_on_multi(&ctx);
+	mipi_dsi_msleep(&ctx, 20);
+
+	return ctx.accum_err;
+}
+
+static int mot_panel_disable(struct drm_panel *panel)
+{
+	struct mot_panel *priv = to_mot_panel(panel);
+	struct mipi_dsi_multi_context ctx = { .dsi = priv->dsi };
+
+	mipi_dsi_dcs_set_display_off_multi(&ctx);
+	mipi_dsi_dcs_enter_sleep_mode_multi(&ctx);
+	mipi_dsi_msleep(&ctx, 70);
+
+	return ctx.accum_err;
+}
+
+static int mot_panel_unprepare(struct drm_panel *panel)
+{
+	struct mot_panel *priv = to_mot_panel(panel);
+
+	usleep_range(10000, 11000);
+
+	gpiod_set_value_cansleep(priv->reset_gpio, 1);
+	usleep_range(5000, 6000);
+
+	regulator_bulk_disable(ARRAY_SIZE(mot_panel_supplies), priv->supplies);
+
+	return 0;
+}
+
+static const struct drm_display_mode mot_panel_mode = {
+	.clock = (540 + 32 + 32 + 16) * (960 + 12 + 12 + 8) * 60 / 1000,
+	.hdisplay = 540,
+	.hsync_start = 540 + 32,
+	.hsync_end = 540 + 32 + 32,
+	.htotal = 540 + 32 + 32 + 16,
+	.vdisplay = 960,
+	.vsync_start = 960 + 12,
+	.vsync_end = 960 + 12 + 12,
+	.vtotal = 960 + 12 + 12 + 8,
+	.width_mm = 51,
+	.height_mm = 91,
+	.type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
+};
+
+static int mot_panel_get_modes(struct drm_panel *panel,
+			       struct drm_connector *connector)
+{
+	return drm_connector_helper_get_modes_fixed(connector, &mot_panel_mode);
+}
+
+static const struct drm_panel_funcs mot_panel_panel_funcs = {
+	.prepare = mot_panel_prepare,
+	.disable = mot_panel_disable,
+	.unprepare = mot_panel_unprepare,
+	.get_modes = mot_panel_get_modes,
+};
+
+static int mot_panel_probe(struct mipi_dsi_device *dsi)
+{
+	struct device *dev = &dsi->dev;
+	struct mot_panel *priv;
+	int ret;
+
+	priv = devm_drm_panel_alloc(dev, struct mot_panel, panel,
+				    &mot_panel_panel_funcs,
+				    DRM_MODE_CONNECTOR_DSI);
+	if (IS_ERR(priv))
+		return PTR_ERR(priv);
+
+	ret = devm_regulator_bulk_get_const(dev, ARRAY_SIZE(mot_panel_supplies),
+					    mot_panel_supplies, &priv->supplies);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "failed to get supplies\n");
+
+	priv->reset_gpio = devm_gpiod_get_optional(dev, "reset",
+						   GPIOD_OUT_HIGH);
+	if (IS_ERR(priv->reset_gpio))
+		return dev_err_probe(dev, PTR_ERR(priv->reset_gpio),
+				     "failed to get reset gpios\n");
+
+	priv->dsi = dsi;
+	mipi_dsi_set_drvdata(dsi, priv);
+
+	dsi->lanes = 2;
+	dsi->format = MIPI_DSI_FMT_RGB888;
+	dsi->mode_flags = MIPI_DSI_MODE_LPM;
+
+	ret = drm_panel_of_backlight(&priv->panel);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "failed to get backlight\n");
+
+	drm_panel_add(&priv->panel);
+
+	ret = devm_mipi_dsi_attach(dev, dsi);
+	if (ret < 0) {
+		drm_panel_remove(&priv->panel);
+		return dev_err_probe(dev, ret, "failed to attach to DSI host\n");
+	}
+
+	return 0;
+}
+
+static void mot_panel_remove(struct mipi_dsi_device *dsi)
+{
+	struct mot_panel *priv = mipi_dsi_get_drvdata(dsi);
+
+	drm_panel_remove(&priv->panel);
+}
+
+static const struct of_device_id mot_panel_of_match[] = {
+	{ .compatible = "motorola,mot-panel" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mot_panel_of_match);
+
+static struct mipi_dsi_driver mot_panel_driver = {
+	.driver = {
+		.name = "panel-motorola-mot",
+		.of_match_table = mot_panel_of_match,
+	},
+	.probe = mot_panel_probe,
+	.remove = mot_panel_remove,
+};
+module_mipi_dsi_driver(mot_panel_driver);
+
+MODULE_AUTHOR("Svyatoslav Ryhel <clamor95@gmail.com>");
+MODULE_DESCRIPTION("Motorola MOT panel driver");
+MODULE_LICENSE("GPL");
-- 
2.51.0

Claude review: gpu/drm: panel: add support for DSI panel used in Motorola Atrix 4G and Droid X2

[Claude Code Review Bot]

Patch Review

> +config DRM_PANEL_MOTOROLA_MOT
> +	tristate "Atrix 4G and Droid X2 540x960 DSI video mode panel"

The Kconfig describes this as a "video mode panel", but:

> +	dsi->mode_flags = MIPI_DSI_MODE_LPM;

The mode flags do not include `MIPI_DSI_MODE_VIDEO`. Without that flag, the DSI host will operate in command mode, not video mode. Other command-mode panel drivers (e.g., panel-sharp-lq101r1sx01, panel-lg-sw43408) similarly set only `MIPI_DSI_MODE_LPM`. If this panel genuinely operates in video mode, `MIPI_DSI_MODE_VIDEO` needs to be added to `mode_flags`. If it's actually a command-mode panel, the Kconfig description should be corrected. Which is it?

> +static int mot_panel_prepare(struct drm_panel *panel)
> +{
> +	...
> +	ret = regulator_bulk_enable(ARRAY_SIZE(mot_panel_supplies), priv->supplies);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to enable power supplies: %d\n", ret);
> +		return ret;
> +	}
> +
> +	mot_panel_reset(priv);
> +
> +	mipi_dsi_generic_write_seq_multi(&ctx, 0xf0, 0x5a, 0x5a);
> +	...
> +	mot_es2(&ctx);
> +	...
> +	return ctx.accum_err;

If any of the DSI commands fail, `ctx.accum_err` will be non-zero and `mot_panel_prepare` returns an error. The `drm_panel_prepare` framework function will then not set `panel->prepared = true`, which means the subsequent `drm_panel_unprepare` call will skip the unprepare callback entirely. The regulators enabled at the top of this function will remain enabled with no cleanup path. The reset GPIO is also left deasserted. To fix this, the error return should disable regulators and reassert reset before returning.

> +#include <video/mipi_display.h>

This header defines `MIPI_DCS_*` constants. The driver uses the `_multi` helper functions exclusively (e.g., `mipi_dsi_dcs_exit_sleep_mode_multi`) which reference those constants internally, so this include does not appear to be directly needed by the driver.

The rest of the driver -- probe/remove lifecycle, mode definition, init sequence structure, GPIO handling -- looks correct.

---
Generated by Claude Code Patch Reviewer

Claude review: gpu/drm: panel: add support for DSI panel used in Motorola Atrix 4G and Droid X2

[Claude Code Review Bot]

Overall Series Review

Subject: gpu/drm: panel: add support for DSI panel used in Motorola Atrix 4G and Droid X2
Author: Svyatoslav Ryhel <clamor95@gmail.com>
Patches: 3
Reviewed: 2026-02-24T10:38:13.651516

---

This is a two-patch series adding support for a DSI LCD panel used in Motorola Atrix 4G and Droid X2 smartphones. The first patch adds the devicetree binding documentation and the second adds the panel driver. The panel is 540x960, 24-bit RGB, connected via DSI with 2 lanes. The vendor and model are unknown, so a generic compatible based on the board name "Mot" is used.

The driver follows modern panel driver conventions: it uses `devm_drm_panel_alloc`, the `mipi_dsi_multi_context` pattern for init sequences, `devm_regulator_bulk_get_const`, and `drm_connector_helper_get_modes_fixed`. The overall structure is clean.

There is one significant concern: the Kconfig help text describes this as a "video mode panel" but the driver only sets `MIPI_DSI_MODE_LPM` in the DSI mode flags, which means the panel will operate in command mode. Either the description is inaccurate or the flag `MIPI_DSI_MODE_VIDEO` is missing. There is also a resource leak on the error path in prepare.

---
Generated by Claude Code Patch Reviewer