[PATCH V5 0/4] drm/panel: Add Magnachip D53E6EA8966 Panel Controller

[PATCH V5 0/4] drm/panel: Add Magnachip D53E6EA8966 Panel Controller

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Add the Magnachip D53E6EA8966 panel IC controller for display panels
such as the Samsung AMS495QA01 panel as found on the Anbernic RG503.
This panel uses DSI to receive video signals, but 3-wire SPI to receive
command signals.

Changes since V4:
 - Renamed driver from the panel model to the panel IC controller per
   DRM team.
 - Added a drm_of helper function of drm_of_get_dsi_bus() to handle
   finding and populating the DSI node when the DSI node is not the
   parent of the DSI controlled display.
 - Converted the documented commands to constants to make it more
   readable.
 - Reset GPIO is now required and documented as GPIO_ACTIVE_LOW.
 - Removed "prepared" logic from panel.

Changes since V3:
 - Updated documentation to add spi-peripheral-props.yaml per updates
   made for similar devices. Note that I removed a "Reviewed-by" tag
   from Rob Herring since this change probably needs to be confirmed.
 - Added binding for RG503, since this device is now accepted with this
   request: https://lore.kernel.org/linux-rockchip/166274831283.21181.6861718157177507544.b4-ty@sntech.de/

Changes since V2:
 - Added 50hz mode at request of userspace devs.
 - Renamed "dupa" to panel name. Good catch Maya.
 - Added Maya's Signed-off-by.
 - Removed check for max backlight, since it is already done by
   backlight_device_set_brightness.
 - Fixed minor formatting issues on devicetree binding documentation
   and added port to provided example.

Changes since V1:
 - Removed errant reference to backlight in documentation. This is an
   OLED panel.
 - Made elvss regulator optional. In my case its hard wired and not
   controllable.
 - Added "prepared" enum to track panel status to prevent unbalanced
   regulator enable/disable.


Chris Morgan (4):
  drm: of: Add drm_of_get_dsi_bus helper function
  dt-bindings: display: panel: Add Magnachip D53E6EA8966
  drm/panel: Add Magnachip D53E6EA8966 Panel Driver
  arm64: dts: rockchip: add display to RG503

 .../display/panel/magnachip,d53e6ea8966.yaml  |  62 +++
 .../dts/rockchip/rk3566-anbernic-rg503.dts    |  55 ++
 drivers/gpu/drm/drm_of.c                      |  62 +++
 drivers/gpu/drm/panel/Kconfig                 |  10 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 .../drm/panel/panel-magnachip-d53e6ea8966.c   | 515 ++++++++++++++++++
 include/drm/drm_of.h                          |  11 +
 7 files changed, 716 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml
 create mode 100644 drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c

-- 
2.34.1

[PATCH V5 0/4] drm/panel: Add Magnachip D53E6EA8966 Panel Controller

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Add the Magnachip D53E6EA8966 panel IC controller for display panels
such as the Samsung AMS495QA01 panel as found on the Anbernic RG503.
This panel uses DSI to receive video signals, but 3-wire SPI to receive
command signals.

Changes since V4:
 - Renamed driver from the panel model to the panel IC controller per
   DRM team.
 - Added a drm_of helper function of drm_of_get_dsi_bus() to handle
   finding and populating the DSI node when the DSI node is not the
   parent of the DSI controlled display.
 - Converted the documented commands to constants to make it more
   readable.
 - Reset GPIO is now required and documented as GPIO_ACTIVE_LOW.
 - Removed "prepared" logic from panel.

Changes since V3:
 - Updated documentation to add spi-peripheral-props.yaml per updates
   made for similar devices. Note that I removed a "Reviewed-by" tag
   from Rob Herring since this change probably needs to be confirmed.
 - Added binding for RG503, since this device is now accepted with this
   request: https://lore.kernel.org/linux-rockchip/166274831283.21181.6861718157177507544.b4-ty@sntech.de/

Changes since V2:
 - Added 50hz mode at request of userspace devs.
 - Renamed "dupa" to panel name. Good catch Maya.
 - Added Maya's Signed-off-by.
 - Removed check for max backlight, since it is already done by
   backlight_device_set_brightness.
 - Fixed minor formatting issues on devicetree binding documentation
   and added port to provided example.

Changes since V1:
 - Removed errant reference to backlight in documentation. This is an
   OLED panel.
 - Made elvss regulator optional. In my case its hard wired and not
   controllable.
 - Added "prepared" enum to track panel status to prevent unbalanced
   regulator enable/disable.


Chris Morgan (4):
  drm: of: Add drm_of_get_dsi_bus helper function
  dt-bindings: display: panel: Add Magnachip D53E6EA8966
  drm/panel: Add Magnachip D53E6EA8966 Panel Driver
  arm64: dts: rockchip: add display to RG503

 .../display/panel/magnachip,d53e6ea8966.yaml  |  62 +++
 .../dts/rockchip/rk3566-anbernic-rg503.dts    |  55 ++
 drivers/gpu/drm/drm_of.c                      |  62 +++
 drivers/gpu/drm/panel/Kconfig                 |  10 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 .../drm/panel/panel-magnachip-d53e6ea8966.c   | 515 ++++++++++++++++++
 include/drm/drm_of.h                          |  11 +
 7 files changed, 716 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml
 create mode 100644 drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c

-- 
2.34.1

[PATCH V5 1/4] drm: of: Add drm_of_get_dsi_bus helper function

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Add helper function to find DSI host for devices where DSI panel is not
a minor of a DSI bus (such as the Samsung AMS495QA01 panel or the
official Raspberry Pi touchscreen display).

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
---
 drivers/gpu/drm/drm_of.c | 62 ++++++++++++++++++++++++++++++++++++++++
 include/drm/drm_of.h     | 11 +++++++
 2 files changed, 73 insertions(+)

diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
index 7bbcb999bb75..7d89ac164069 100644
--- a/drivers/gpu/drm/drm_of.c
+++ b/drivers/gpu/drm/drm_of.c
@@ -10,6 +10,7 @@
 #include <drm/drm_crtc.h>
 #include <drm/drm_device.h>
 #include <drm/drm_encoder.h>
+#include <drm/drm_mipi_dsi.h>
 #include <drm/drm_of.h>
 #include <drm/drm_panel.h>
 
@@ -493,3 +494,64 @@ int drm_of_get_data_lanes_count_ep(const struct device_node *port,
 	return ret;
 }
 EXPORT_SYMBOL_GPL(drm_of_get_data_lanes_count_ep);
+
+/**
+ * drm_of_get_dsi_bus - find the DSI bus for a given device
+ * @dev: parent device of display (SPI, I2C)
+ * @dsi_host: DSI host to be populated
+ * @info: DSI device info to be updated with correct DSI node
+ *
+ * Given a panel device parented to a non-DSI device, follow the
+ * devicetree to find the correct DSI host node and populate the
+ * dsi_host with the correct host and info with the correct node.
+ * Returns zero if successful, -EPROBE_DEFER if the DSI host is
+ * found but not available, or -ENODEV otherwise.
+ */
+int drm_of_get_dsi_bus(struct device *dev,
+			      struct mipi_dsi_host **dsi_host,
+			      struct mipi_dsi_device_info *info)
+{
+	struct device_node *endpoint, *dsi_host_node;
+
+	/*
+	 * Get first endpoint child from device.
+	 */
+	endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
+	if (!endpoint)
+		return -ENODEV;
+
+	/*
+	 * Follow the first endpoint to get the DSI host node.
+	 */
+	dsi_host_node = of_graph_get_remote_port_parent(endpoint);
+	if (!dsi_host_node)
+		goto error;
+
+	/*
+	 * Get the DSI host from the DSI host node. If we get an error
+	 * or the return is null assume we're not ready to probe just
+	 * yet. Release the DSI host node since we're done with it.
+	 */
+	*dsi_host = of_find_mipi_dsi_host_by_node(dsi_host_node);
+	of_node_put(dsi_host_node);
+	if (IS_ERR_OR_NULL(*dsi_host)) {
+		of_node_put(endpoint);
+		return -EPROBE_DEFER;
+	}
+
+	/*
+	 * Set the node of the mipi_dsi_device_info to the correct node
+	 * and then release the endpoint node since we're done with it.
+	 */
+	info->node = of_graph_get_remote_port(endpoint);
+	if (IS_ERR_OR_NULL(info->node))
+		goto error;
+
+	of_node_put(endpoint);
+	return 0;
+
+error:
+	of_node_put(endpoint);
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(drm_of_get_dsi_bus);
diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
index 10ab58c40746..a694ce71c3b2 100644
--- a/include/drm/drm_of.h
+++ b/include/drm/drm_of.h
@@ -15,6 +15,8 @@ struct drm_encoder;
 struct drm_panel;
 struct drm_bridge;
 struct device_node;
+struct mipi_dsi_device_info;
+struct mipi_dsi_host;
 
 /**
  * enum drm_lvds_dual_link_pixels - Pixel order of an LVDS dual-link connection
@@ -56,6 +58,9 @@ int drm_of_get_data_lanes_count_ep(const struct device_node *port,
 				   int port_reg, int reg,
 				   const unsigned int min,
 				   const unsigned int max);
+int drm_of_get_dsi_bus(struct device *dev,
+		       struct mipi_dsi_host **dsi_host,
+		       struct mipi_dsi_device_info *info);
 #else
 static inline uint32_t drm_of_crtc_port_mask(struct drm_device *dev,
 					  struct device_node *port)
@@ -127,6 +132,12 @@ drm_of_get_data_lanes_count_ep(const struct device_node *port,
 {
 	return -EINVAL;
 }
+static int drm_of_get_dsi_bus(struct device *dev,
+			      struct mipi_dsi_host **dsi_host,
+			      struct mipi_dsi_device_info *info);
+{
+	return -EINVAL;
+}
 #endif
 
 /*
-- 
2.34.1

[PATCH V5 1/4] drm: of: Add drm_of_get_dsi_bus helper function

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Add helper function to find DSI host for devices where DSI panel is not
a minor of a DSI bus (such as the Samsung AMS495QA01 panel or the
official Raspberry Pi touchscreen display).

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
---
 drivers/gpu/drm/drm_of.c | 62 ++++++++++++++++++++++++++++++++++++++++
 include/drm/drm_of.h     | 11 +++++++
 2 files changed, 73 insertions(+)

diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
index 7bbcb999bb75..7d89ac164069 100644
--- a/drivers/gpu/drm/drm_of.c
+++ b/drivers/gpu/drm/drm_of.c
@@ -10,6 +10,7 @@
 #include <drm/drm_crtc.h>
 #include <drm/drm_device.h>
 #include <drm/drm_encoder.h>
+#include <drm/drm_mipi_dsi.h>
 #include <drm/drm_of.h>
 #include <drm/drm_panel.h>
 
@@ -493,3 +494,64 @@ int drm_of_get_data_lanes_count_ep(const struct device_node *port,
 	return ret;
 }
 EXPORT_SYMBOL_GPL(drm_of_get_data_lanes_count_ep);
+
+/**
+ * drm_of_get_dsi_bus - find the DSI bus for a given device
+ * @dev: parent device of display (SPI, I2C)
+ * @dsi_host: DSI host to be populated
+ * @info: DSI device info to be updated with correct DSI node
+ *
+ * Given a panel device parented to a non-DSI device, follow the
+ * devicetree to find the correct DSI host node and populate the
+ * dsi_host with the correct host and info with the correct node.
+ * Returns zero if successful, -EPROBE_DEFER if the DSI host is
+ * found but not available, or -ENODEV otherwise.
+ */
+int drm_of_get_dsi_bus(struct device *dev,
+			      struct mipi_dsi_host **dsi_host,
+			      struct mipi_dsi_device_info *info)
+{
+	struct device_node *endpoint, *dsi_host_node;
+
+	/*
+	 * Get first endpoint child from device.
+	 */
+	endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
+	if (!endpoint)
+		return -ENODEV;
+
+	/*
+	 * Follow the first endpoint to get the DSI host node.
+	 */
+	dsi_host_node = of_graph_get_remote_port_parent(endpoint);
+	if (!dsi_host_node)
+		goto error;
+
+	/*
+	 * Get the DSI host from the DSI host node. If we get an error
+	 * or the return is null assume we're not ready to probe just
+	 * yet. Release the DSI host node since we're done with it.
+	 */
+	*dsi_host = of_find_mipi_dsi_host_by_node(dsi_host_node);
+	of_node_put(dsi_host_node);
+	if (IS_ERR_OR_NULL(*dsi_host)) {
+		of_node_put(endpoint);
+		return -EPROBE_DEFER;
+	}
+
+	/*
+	 * Set the node of the mipi_dsi_device_info to the correct node
+	 * and then release the endpoint node since we're done with it.
+	 */
+	info->node = of_graph_get_remote_port(endpoint);
+	if (IS_ERR_OR_NULL(info->node))
+		goto error;
+
+	of_node_put(endpoint);
+	return 0;
+
+error:
+	of_node_put(endpoint);
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(drm_of_get_dsi_bus);
diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
index 10ab58c40746..a694ce71c3b2 100644
--- a/include/drm/drm_of.h
+++ b/include/drm/drm_of.h
@@ -15,6 +15,8 @@ struct drm_encoder;
 struct drm_panel;
 struct drm_bridge;
 struct device_node;
+struct mipi_dsi_device_info;
+struct mipi_dsi_host;
 
 /**
  * enum drm_lvds_dual_link_pixels - Pixel order of an LVDS dual-link connection
@@ -56,6 +58,9 @@ int drm_of_get_data_lanes_count_ep(const struct device_node *port,
 				   int port_reg, int reg,
 				   const unsigned int min,
 				   const unsigned int max);
+int drm_of_get_dsi_bus(struct device *dev,
+		       struct mipi_dsi_host **dsi_host,
+		       struct mipi_dsi_device_info *info);
 #else
 static inline uint32_t drm_of_crtc_port_mask(struct drm_device *dev,
 					  struct device_node *port)
@@ -127,6 +132,12 @@ drm_of_get_data_lanes_count_ep(const struct device_node *port,
 {
 	return -EINVAL;
 }
+static int drm_of_get_dsi_bus(struct device *dev,
+			      struct mipi_dsi_host **dsi_host,
+			      struct mipi_dsi_device_info *info);
+{
+	return -EINVAL;
+}
 #endif
 
 /*
-- 
2.34.1

Re: [PATCH V5 1/4] drm: of: Add drm_of_get_dsi_bus helper function

[Linus Walleij]

On Wed, Dec 14, 2022 at 7:06 PM Chris Morgan <macroalpha82@gmail.com> wrote:

> From: Chris Morgan <macromorgan@hotmail.com>
>
> Add helper function to find DSI host for devices where DSI panel is not
> a minor of a DSI bus (such as the Samsung AMS495QA01 panel or the
> official Raspberry Pi touchscreen display).
>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>

Nice, exactly as it should be IMO.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij

Re: [PATCH V5 1/4] drm: of: Add drm_of_get_dsi_bus helper function

[Linus Walleij]

On Wed, Dec 14, 2022 at 7:06 PM Chris Morgan <macroalpha82@gmail.com> wrote:

> From: Chris Morgan <macromorgan@hotmail.com>
>
> Add helper function to find DSI host for devices where DSI panel is not
> a minor of a DSI bus (such as the Samsung AMS495QA01 panel or the
> official Raspberry Pi touchscreen display).
>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>

Nice, exactly as it should be IMO.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij

[PATCH V5 2/4] dt-bindings: display: panel: Add Magnachip D53E6EA8966

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Add documentation for Magnachip D53E6EA8966 based panels such as the
Samsung AMS495QA01 panel.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
---
 .../display/panel/magnachip,d53e6ea8966.yaml  | 62 +++++++++++++++++++
 1 file changed, 62 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml

diff --git a/Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml b/Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml
new file mode 100644
index 000000000000..0a57a303a758
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml
@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/samsung,ams495qa01.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Magnachip D53E6EA8966 based display panel
+
+description: |
+  Magnachip D53E6EA8966 based display panels, such as the one found on
+  the Anbernic RG503 that is combined with a 940x544 OLED Samsung
+  AMS495QA01.
+
+maintainers:
+  - Chris Morgan <macromorgan@hotmail.com>
+
+allOf:
+  - $ref: panel-common.yaml#
+
+properties:
+  compatible:
+    const: samsung,ams495qa01
+
+  reg: true
+  reset-gpios:
+    description: reset gpio, must be GPIO_ACTIVE_LOW
+  elvdd-supply:
+    description: regulator that supplies voltage to the panel display
+  enable-gpios: true
+  port: true
+  vdd-supply:
+    description: regulator that supplies voltage to panel logic
+
+required:
+  - compatible
+  - reg
+  - reset-gpios
+  - vdd-supply
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+        panel@0 {
+            compatible = "samsung,ams495qa01";
+            reg = <0>;
+            reset-gpios = <&gpio4 0 GPIO_ACTIVE_LOW>;
+            vdd-supply = <&vcc_3v3>;
+
+            port {
+                mipi_in_panel: endpoint {
+                  remote-endpoint = <&mipi_out_panel>;
+                };
+            };
+        };
+    };
+
+...
-- 
2.34.1

[PATCH V5 2/4] dt-bindings: display: panel: Add Magnachip D53E6EA8966

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Add documentation for Magnachip D53E6EA8966 based panels such as the
Samsung AMS495QA01 panel.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
---
 .../display/panel/magnachip,d53e6ea8966.yaml  | 62 +++++++++++++++++++
 1 file changed, 62 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml

diff --git a/Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml b/Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml
new file mode 100644
index 000000000000..0a57a303a758
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml
@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/samsung,ams495qa01.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Magnachip D53E6EA8966 based display panel
+
+description: |
+  Magnachip D53E6EA8966 based display panels, such as the one found on
+  the Anbernic RG503 that is combined with a 940x544 OLED Samsung
+  AMS495QA01.
+
+maintainers:
+  - Chris Morgan <macromorgan@hotmail.com>
+
+allOf:
+  - $ref: panel-common.yaml#
+
+properties:
+  compatible:
+    const: samsung,ams495qa01
+
+  reg: true
+  reset-gpios:
+    description: reset gpio, must be GPIO_ACTIVE_LOW
+  elvdd-supply:
+    description: regulator that supplies voltage to the panel display
+  enable-gpios: true
+  port: true
+  vdd-supply:
+    description: regulator that supplies voltage to panel logic
+
+required:
+  - compatible
+  - reg
+  - reset-gpios
+  - vdd-supply
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+        panel@0 {
+            compatible = "samsung,ams495qa01";
+            reg = <0>;
+            reset-gpios = <&gpio4 0 GPIO_ACTIVE_LOW>;
+            vdd-supply = <&vcc_3v3>;
+
+            port {
+                mipi_in_panel: endpoint {
+                  remote-endpoint = <&mipi_out_panel>;
+                };
+            };
+        };
+    };
+
+...
-- 
2.34.1

Re: [PATCH V5 2/4] dt-bindings: display: panel: Add Magnachip D53E6EA8966

[Rob Herring]

On Wed, 14 Dec 2022 12:06:09 -0600, Chris Morgan wrote:
> From: Chris Morgan <macromorgan@hotmail.com>
> 
> Add documentation for Magnachip D53E6EA8966 based panels such as the
> Samsung AMS495QA01 panel.
> 
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> ---
>  .../display/panel/magnachip,d53e6ea8966.yaml  | 62 +++++++++++++++++++
>  1 file changed, 62 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
./Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml: $id: relative path/filename doesn't match actual path or filename
	expected: http://devicetree.org/schemas/display/panel/magnachip,d53e6ea8966.yaml#

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20221214180611.109651-3-macroalpha82@gmail.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

Re: [PATCH V5 2/4] dt-bindings: display: panel: Add Magnachip D53E6EA8966

[Rob Herring]

On Wed, 14 Dec 2022 12:06:09 -0600, Chris Morgan wrote:
> From: Chris Morgan <macromorgan@hotmail.com>
> 
> Add documentation for Magnachip D53E6EA8966 based panels such as the
> Samsung AMS495QA01 panel.
> 
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> ---
>  .../display/panel/magnachip,d53e6ea8966.yaml  | 62 +++++++++++++++++++
>  1 file changed, 62 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
./Documentation/devicetree/bindings/display/panel/magnachip,d53e6ea8966.yaml: $id: relative path/filename doesn't match actual path or filename
	expected: http://devicetree.org/schemas/display/panel/magnachip,d53e6ea8966.yaml#

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20221214180611.109651-3-macroalpha82@gmail.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

Re: [PATCH V5 2/4] dt-bindings: display: panel: Add Magnachip D53E6EA8966

[Linus Walleij]

On Wed, Dec 14, 2022 at 7:06 PM Chris Morgan <macroalpha82@gmail.com> wrote:

> From: Chris Morgan <macromorgan@hotmail.com>
>
> Add documentation for Magnachip D53E6EA8966 based panels such as the
> Samsung AMS495QA01 panel.
>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
(...)
>  .../display/panel/magnachip,d53e6ea8966.yaml  | 62 +++++++++++++++++++

It's fine to keep this as samsung,ams495qa01.

Just mention that it uses the magnachip controller in the
description.

That Linux implements this with a generic driver that handles
all (in theory possible) magnachip-based products is a linuxism
and does not need to be in the bindings.

Yours,
Linus Walleij

Re: [PATCH V5 2/4] dt-bindings: display: panel: Add Magnachip D53E6EA8966

[Linus Walleij]

On Wed, Dec 14, 2022 at 7:06 PM Chris Morgan <macroalpha82@gmail.com> wrote:

> From: Chris Morgan <macromorgan@hotmail.com>
>
> Add documentation for Magnachip D53E6EA8966 based panels such as the
> Samsung AMS495QA01 panel.
>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
(...)
>  .../display/panel/magnachip,d53e6ea8966.yaml  | 62 +++++++++++++++++++

It's fine to keep this as samsung,ams495qa01.

Just mention that it uses the magnachip controller in the
description.

That Linux implements this with a generic driver that handles
all (in theory possible) magnachip-based products is a linuxism
and does not need to be in the bindings.

Yours,
Linus Walleij

Re: [PATCH V5 2/4] dt-bindings: display: panel: Add Magnachip D53E6EA8966

[Chris Morgan]

On Thu, Dec 15, 2022 at 09:47:19AM +0100, Linus Walleij wrote:
> On Wed, Dec 14, 2022 at 7:06 PM Chris Morgan <macroalpha82@gmail.com> wrote:
> 
> > From: Chris Morgan <macromorgan@hotmail.com>
> >
> > Add documentation for Magnachip D53E6EA8966 based panels such as the
> > Samsung AMS495QA01 panel.
> >
> > Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> > Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> (...)
> >  .../display/panel/magnachip,d53e6ea8966.yaml  | 62 +++++++++++++++++++
> 
> It's fine to keep this as samsung,ams495qa01.
> 

Would the device tree team be okay with that change? The driver name
itself has changed and I fear possible confusion if someone is looking
for docs by driver name.

Otherwise I noticed I had an outdated version of the dt-schema and
missed an error, so I have to resubmit either way to fix it. The
horrors of upgrading your build machine...

Thank you

> Just mention that it uses the magnachip controller in the
> description.
> 
> That Linux implements this with a generic driver that handles
> all (in theory possible) magnachip-based products is a linuxism
> and does not need to be in the bindings.
> 
> Yours,
> Linus Walleij

Re: [PATCH V5 2/4] dt-bindings: display: panel: Add Magnachip D53E6EA8966

[Chris Morgan]

On Thu, Dec 15, 2022 at 09:47:19AM +0100, Linus Walleij wrote:
> On Wed, Dec 14, 2022 at 7:06 PM Chris Morgan <macroalpha82@gmail.com> wrote:
> 
> > From: Chris Morgan <macromorgan@hotmail.com>
> >
> > Add documentation for Magnachip D53E6EA8966 based panels such as the
> > Samsung AMS495QA01 panel.
> >
> > Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> > Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> (...)
> >  .../display/panel/magnachip,d53e6ea8966.yaml  | 62 +++++++++++++++++++
> 
> It's fine to keep this as samsung,ams495qa01.
> 

Would the device tree team be okay with that change? The driver name
itself has changed and I fear possible confusion if someone is looking
for docs by driver name.

Otherwise I noticed I had an outdated version of the dt-schema and
missed an error, so I have to resubmit either way to fix it. The
horrors of upgrading your build machine...

Thank you

> Just mention that it uses the magnachip controller in the
> description.
> 
> That Linux implements this with a generic driver that handles
> all (in theory possible) magnachip-based products is a linuxism
> and does not need to be in the bindings.
> 
> Yours,
> Linus Walleij

Re: [PATCH V5 2/4] dt-bindings: display: panel: Add Magnachip D53E6EA8966

[Rob Herring]

On Thu, Dec 15, 2022 at 08:44:56AM -0600, Chris Morgan wrote:
> On Thu, Dec 15, 2022 at 09:47:19AM +0100, Linus Walleij wrote:
> > On Wed, Dec 14, 2022 at 7:06 PM Chris Morgan <macroalpha82@gmail.com> wrote:
> > 
> > > From: Chris Morgan <macromorgan@hotmail.com>
> > >
> > > Add documentation for Magnachip D53E6EA8966 based panels such as the
> > > Samsung AMS495QA01 panel.
> > >
> > > Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> > > Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> > (...)
> > >  .../display/panel/magnachip,d53e6ea8966.yaml  | 62 +++++++++++++++++++
> > 
> > It's fine to keep this as samsung,ams495qa01.
> > 
> 
> Would the device tree team be okay with that change? The driver name
> itself has changed and I fear possible confusion if someone is looking
> for docs by driver name.

Doesn't matter to me either way.

Rob

Re: [PATCH V5 2/4] dt-bindings: display: panel: Add Magnachip D53E6EA8966

[Rob Herring]

On Thu, Dec 15, 2022 at 08:44:56AM -0600, Chris Morgan wrote:
> On Thu, Dec 15, 2022 at 09:47:19AM +0100, Linus Walleij wrote:
> > On Wed, Dec 14, 2022 at 7:06 PM Chris Morgan <macroalpha82@gmail.com> wrote:
> > 
> > > From: Chris Morgan <macromorgan@hotmail.com>
> > >
> > > Add documentation for Magnachip D53E6EA8966 based panels such as the
> > > Samsung AMS495QA01 panel.
> > >
> > > Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> > > Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> > (...)
> > >  .../display/panel/magnachip,d53e6ea8966.yaml  | 62 +++++++++++++++++++
> > 
> > It's fine to keep this as samsung,ams495qa01.
> > 
> 
> Would the device tree team be okay with that change? The driver name
> itself has changed and I fear possible confusion if someone is looking
> for docs by driver name.

Doesn't matter to me either way.

Rob

[PATCH V5 3/4] drm/panel: Add Magnachip D53E6EA8966 Panel Driver

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Support Magnachip D53E6EA8966 based panels such as the Samsung
AMS495QA01 panel as found on the Anbernic RG503. Note this driver
supports only the AMS495QA01 today which receives video signals via DSI,
however it receives commands via 3-wire SPI.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
---
 drivers/gpu/drm/panel/Kconfig                 |  10 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 .../drm/panel/panel-magnachip-d53e6ea8966.c   | 515 ++++++++++++++++++
 3 files changed, 526 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index a582ddd583c2..1f81fe8a2f8a 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -288,6 +288,16 @@ config DRM_PANEL_LG_LG4573
 	  Say Y here if you want to enable support for LG4573 RGB panel.
 	  To compile this driver as a module, choose M here.
 
+config DRM_PANEL_MAGNACHIP_D53E6EA8966
+	tristate "Magnachip D53E6EA8966 DSI panel"
+	depends on OF && SPI
+	depends on DRM_MIPI_DSI
+	select DRM_MIPI_DBI
+	help
+	  DRM panel driver for the Samsung AMS495QA01 panel controlled
+	  with the Magnachip D53E6EA8966 panel IC. This panel receives
+	  video data via DSI but commands via 3-Wire 9-bit SPI.
+
 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 34e717382dbb..7c09cd480c69 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK050H3146W) += panel-leadtek-ltk050h3146w.o
 obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK500HD1829) += panel-leadtek-ltk500hd1829.o
 obj-$(CONFIG_DRM_PANEL_LG_LB035Q02) += panel-lg-lb035q02.o
 obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o
+obj-$(CONFIG_DRM_PANEL_MAGNACHIP_D53E6EA8966) += panel-magnachip-d53e6ea8966.o
 obj-$(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-magnachip-d53e6ea8966.c b/drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c
new file mode 100644
index 000000000000..c1b80f2f296c
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c
@@ -0,0 +1,515 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Magnachip d53e6ea8966 MIPI-DSI panel driver
+ * Copyright (C) 2022 Chris Morgan
+ */
+
+#include <drm/drm_mipi_dbi.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/media-bus-format.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_graph.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+
+#include <video/mipi_display.h>
+
+/* Forward declaration for use in backlight function */
+struct d53e6ea8966;
+
+/* Panel info, unique to each panel */
+struct d53e6ea8966_panel_info {
+	/** @display_modes: the supported display modes */
+	const struct drm_display_mode *display_modes;
+	/** @num_modes: the number of supported display modes */
+	unsigned int num_modes;
+	/** @width_mm: panel width in mm */
+	u16 width_mm;
+	/** @height_mm: panel height in mm */
+	u16 height_mm;
+	/** @bus_flags: drm bus flags for panel */
+	u32 bus_flags;
+	/** @panel_funcs: panel functions for panel */
+	const struct drm_panel_funcs *panel_funcs;
+	/** @backlight: panel backlight registration or NULL */
+	int (*backlight_register)(struct d53e6ea8966 *db);
+};
+
+struct d53e6ea8966 {
+	/** @dev: the container device */
+	struct device *dev;
+	/** @dbi: the DBI bus abstraction handle */
+	struct mipi_dbi dbi;
+	/** @panel: the DRM panel instance for this device */
+	struct drm_panel panel;
+	/** @reset: reset GPIO line */
+	struct gpio_desc *reset;
+	/** @enable: enable GPIO line */
+	struct gpio_desc *enable;
+	/** @reg_vdd: VDD supply regulator for panel logic */
+	struct regulator *reg_vdd;
+	/** @reg_elvdd: ELVDD supply regulator for panel display */
+	struct regulator *reg_elvdd;
+	/** @dsi_dev: DSI child device (panel) */
+	struct mipi_dsi_device *dsi_dev;
+	/** @bl_dev: pseudo-backlight device for oled panel */
+	struct backlight_device *bl_dev;
+	/** @panel_info: struct containing panel timing and info */
+	const struct d53e6ea8966_panel_info *panel_info;
+};
+
+#define NUM_GAMMA_LEVELS	16
+#define GAMMA_TABLE_COUNT	23
+#define MAX_BRIGHTNESS		(NUM_GAMMA_LEVELS - 1)
+
+#define MCS_ELVSS_ON			0xb1
+#define MCS_TEMP_SWIRE			0xb2
+#define MCS_PASSWORD_0			0xf0
+#define MCS_PASSWORD_1			0xf1
+#define MCS_ANALOG_PWR_CTL_0		0xf4
+#define MCS_ANALOG_PWR_CTL_1		0xf5
+#define MCS_GTCON_SET			0xf7
+#define MCS_GATELESS_SIGNAL_SET		0xf8
+#define MCS_SET_GAMMA			0xf9
+
+static inline struct d53e6ea8966 *to_d53e6ea8966(struct drm_panel *panel)
+{
+	return container_of(panel, struct d53e6ea8966, panel);
+}
+
+/* Table of gamma values provided in datasheet */
+static u8 ams495qa01_gamma[NUM_GAMMA_LEVELS][GAMMA_TABLE_COUNT] = {
+	{0x01, 0x79, 0x78, 0x8d, 0xd9, 0xdf, 0xd5, 0xcb, 0xcf, 0xc5,
+	 0xe5, 0xe0, 0xe4, 0xdc, 0xb8, 0xd4, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x7d, 0x7c, 0x92, 0xd7, 0xdd, 0xd2, 0xcb, 0xd0, 0xc6,
+	 0xe5, 0xe1, 0xe3, 0xda, 0xbd, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x7f, 0x7e, 0x95, 0xd7, 0xde, 0xd2, 0xcb, 0xcf, 0xc5,
+	 0xe5, 0xe3, 0xe3, 0xda, 0xbf, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x82, 0x81, 0x99, 0xd6, 0xdd, 0xd1, 0xca, 0xcf, 0xc3,
+	 0xe4, 0xe3, 0xe3, 0xda, 0xc2, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x84, 0x83, 0x9b, 0xd7, 0xde, 0xd2, 0xc8, 0xce, 0xc2,
+	 0xe4, 0xe3, 0xe2, 0xd9, 0xc3, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x87, 0x86, 0x9f, 0xd6, 0xdd, 0xd1, 0xc7, 0xce, 0xc1,
+	 0xe4, 0xe3, 0xe2, 0xd9, 0xc6, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x89, 0x89, 0xa2, 0xd5, 0xdb, 0xcf, 0xc8, 0xcf, 0xc2,
+	 0xe3, 0xe3, 0xe1, 0xd9, 0xc7, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x8b, 0x8b, 0xa5, 0xd5, 0xdb, 0xcf, 0xc7, 0xce, 0xc0,
+	 0xe3, 0xe3, 0xe1, 0xd8, 0xc7, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x8d, 0x8d, 0xa7, 0xd5, 0xdb, 0xcf, 0xc6, 0xce, 0xc0,
+	 0xe4, 0xe4, 0xe1, 0xd7, 0xc8, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x8f, 0x8f, 0xaa, 0xd4, 0xdb, 0xce, 0xc6, 0xcd, 0xbf,
+	 0xe3, 0xe3, 0xe1, 0xd7, 0xca, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x91, 0x91, 0xac, 0xd3, 0xda, 0xce, 0xc5, 0xcd, 0xbe,
+	 0xe3, 0xe3, 0xe0, 0xd7, 0xca, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x93, 0x93, 0xaf, 0xd3, 0xda, 0xcd, 0xc5, 0xcd, 0xbe,
+	 0xe2, 0xe3, 0xdf, 0xd6, 0xca, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x95, 0x95, 0xb1, 0xd2, 0xd9, 0xcc, 0xc4, 0xcd, 0xbe,
+	 0xe2, 0xe3, 0xdf, 0xd7, 0xcc, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x99, 0x99, 0xb6, 0xd1, 0xd9, 0xcc, 0xc3, 0xcb, 0xbc,
+	 0xe2, 0xe4, 0xdf, 0xd6, 0xcc, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x9c, 0x9c, 0xba, 0xd0, 0xd8, 0xcb, 0xc3, 0xcb, 0xbb,
+	 0xe2, 0xe4, 0xdf, 0xd6, 0xce, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x9f, 0x9f, 0xbe, 0xcf, 0xd7, 0xc9, 0xc2, 0xcb, 0xbb,
+	 0xe1, 0xe3, 0xde, 0xd6, 0xd0, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+};
+
+/*
+ * Table of elvss values provided in datasheet and corresponds to
+ * gamma values.
+ */
+static u8 ams495qa01_elvss[NUM_GAMMA_LEVELS] = {
+	0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15,
+	0x15, 0x15, 0x14, 0x14, 0x13, 0x12,
+};
+
+static int ams495qa01_update_gamma(struct mipi_dbi *dbi, u32 brightness)
+{
+	u32 tmp = brightness;
+
+	mipi_dbi_command_buf(dbi, MCS_SET_GAMMA, ams495qa01_gamma[tmp],
+			     ARRAY_SIZE(ams495qa01_gamma[tmp]));
+	mipi_dbi_command(dbi, MCS_SET_GAMMA, 0x00);
+
+	/* Undocumented command */
+	mipi_dbi_command(dbi, 0x26, 0x00);
+
+	mipi_dbi_command(dbi, MCS_TEMP_SWIRE, ams495qa01_elvss[tmp]);
+
+	return 0;
+}
+
+static int ams495qa01_prepare(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	struct mipi_dbi *dbi = &db->dbi;
+	int ret;
+
+	/* Power up */
+	ret = regulator_enable(db->reg_vdd);
+	if (ret) {
+		dev_err(db->dev, "failed to enable vdd regulator: %d\n", ret);
+		return ret;
+	}
+
+	if (db->reg_elvdd) {
+		ret = regulator_enable(db->reg_elvdd);
+		if (ret) {
+			dev_err(db->dev,
+				"failed to enable elvdd regulator: %d\n", ret);
+			regulator_disable(db->reg_vdd);
+			return ret;
+		}
+	}
+
+	/* Enable */
+	if (db->enable)
+		gpiod_set_value_cansleep(db->enable, 1);
+
+	msleep(50);
+
+	/* Reset */
+	gpiod_set_value_cansleep(db->reset, 1);
+	usleep_range(1000, 5000);
+	gpiod_set_value_cansleep(db->reset, 0);
+	msleep(20);
+
+	/* Panel Init Sequence */
+
+	mipi_dbi_command(dbi, MCS_PASSWORD_0, 0x5a, 0x5a);
+	mipi_dbi_command(dbi, MCS_PASSWORD_1, 0x5a, 0x5a);
+	/* Undocumented commands */
+	mipi_dbi_command(dbi, 0xb0, 0x02);
+	mipi_dbi_command(dbi, 0xf3, 0x3b);
+
+	mipi_dbi_command(dbi, MCS_ANALOG_PWR_CTL_0, 0x33, 0x42, 0x00, 0x08);
+	mipi_dbi_command(dbi, MCS_ANALOG_PWR_CTL_1, 0x00, 0x06, 0x26, 0x35, 0x03);
+
+	/* Undocumented commands */
+	mipi_dbi_command(dbi, 0xf6, 0x02);
+	mipi_dbi_command(dbi, 0xc6, 0x0b, 0x00, 0x00, 0x3c, 0x00, 0x22,
+			 0x00, 0x00, 0x00, 0x00);
+
+	mipi_dbi_command(dbi, MCS_GTCON_SET, 0x20);
+	mipi_dbi_command(dbi, MCS_TEMP_SWIRE, 0x06, 0x06, 0x06, 0x06);
+	mipi_dbi_command(dbi, MCS_ELVSS_ON, 0x07, 0x00, 0x10);
+	mipi_dbi_command(dbi, MCS_GATELESS_SIGNAL_SET, 0x7f, 0x7a,
+			 0x89, 0x67, 0x26, 0x38, 0x00, 0x00, 0x09,
+			 0x67, 0x70, 0x88, 0x7a, 0x76, 0x05, 0x09,
+			 0x23, 0x23, 0x23);
+
+	/* Undocumented commands */
+	mipi_dbi_command(dbi, 0xb5, 0xff, 0xef, 0x35, 0x42, 0x0d, 0xd7,
+			 0xff, 0x07, 0xff, 0xff, 0xfd, 0x00, 0x01,
+			 0xff, 0x05, 0x12, 0x0f, 0xff, 0xff, 0xff,
+			 0xff);
+	mipi_dbi_command(dbi, 0xb4, 0x15);
+	mipi_dbi_command(dbi, 0xb3, 0x00);
+
+	ams495qa01_update_gamma(dbi, MAX_BRIGHTNESS);
+
+	return 0;
+}
+
+static int ams495qa01_enable(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	struct mipi_dbi *dbi = &db->dbi;
+
+	mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
+	msleep(200);
+	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
+	usleep_range(10000, 15000);
+
+	return 0;
+}
+
+static int ams495qa01_disable(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	struct mipi_dbi *dbi = &db->dbi;
+
+	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_OFF);
+	msleep(20);
+	mipi_dbi_command(dbi, MIPI_DCS_ENTER_SLEEP_MODE);
+	msleep(100);
+
+	return 0;
+}
+
+static int ams495qa01_unprepare(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+
+	if (db->enable)
+		gpiod_set_value_cansleep(db->enable, 0);
+
+	gpiod_set_value_cansleep(db->reset, 1);
+
+	if (db->reg_elvdd)
+		regulator_disable(db->reg_elvdd);
+
+	regulator_disable(db->reg_vdd);
+	msleep(100);
+
+	return 0;
+}
+
+static int ams495qa01_get_modes(struct drm_panel *panel,
+				struct drm_connector *connector)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	const struct d53e6ea8966_panel_info *panel_info = db->panel_info;
+	struct drm_display_mode *mode;
+	static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+	unsigned int i;
+
+	for (i = 0; i < panel_info->num_modes; i++) {
+		mode = drm_mode_duplicate(connector->dev,
+					  &panel_info->display_modes[i]);
+		if (!mode)
+			return -ENOMEM;
+
+		drm_mode_set_name(mode);
+		drm_mode_probed_add(connector, mode);
+	}
+
+	connector->display_info.bpc = 8;
+	connector->display_info.width_mm = panel_info->width_mm;
+	connector->display_info.height_mm = panel_info->height_mm;
+	connector->display_info.bus_flags = panel_info->bus_flags;
+
+	drm_display_info_set_bus_formats(&connector->display_info,
+					 &bus_format, 1);
+
+	return 1;
+}
+
+static const struct drm_panel_funcs ams495qa01_panel_funcs = {
+	.disable = ams495qa01_disable,
+	.enable = ams495qa01_enable,
+	.get_modes = ams495qa01_get_modes,
+	.prepare = ams495qa01_prepare,
+	.unprepare = ams495qa01_unprepare,
+};
+
+static int ams495qa01_set_brightness(struct backlight_device *bd)
+{
+	struct d53e6ea8966 *db = bl_get_data(bd);
+	struct mipi_dbi *dbi = &db->dbi;
+	int brightness = bd->props.brightness;
+
+	ams495qa01_update_gamma(dbi, brightness);
+
+	return 0;
+}
+
+static const struct backlight_ops ams495qa01_backlight_ops = {
+	.update_status	= ams495qa01_set_brightness,
+};
+
+static int ams495qa01_backlight_register(struct d53e6ea8966 *db)
+{
+	struct backlight_properties props = {
+		.type		= BACKLIGHT_RAW,
+		.brightness	= MAX_BRIGHTNESS,
+		.max_brightness = MAX_BRIGHTNESS,
+	};
+	struct device *dev = db->dev;
+	int ret = 0;
+
+	db->bl_dev = devm_backlight_device_register(dev, "panel", dev, db,
+						     &ams495qa01_backlight_ops,
+						     &props);
+	if (IS_ERR(db->bl_dev)) {
+		ret = PTR_ERR(db->bl_dev);
+		dev_err(dev, "error registering backlight device (%d)\n", ret);
+	}
+
+	return ret;
+}
+
+static int d53e6ea8966_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct mipi_dsi_host *dsi_host;
+	struct d53e6ea8966 *db;
+	int ret;
+	struct mipi_dsi_device_info info = {
+		.type = "d53e6ea8966",
+		.channel = 0,
+		.node = NULL,
+	};
+
+	db = devm_kzalloc(dev, sizeof(*db), GFP_KERNEL);
+	if (!db)
+		return -ENOMEM;
+
+	spi_set_drvdata(spi, db);
+
+	db->dev = dev;
+
+	db->panel_info = of_device_get_match_data(dev);
+	if (!db->panel_info)
+		return -EINVAL;
+
+	db->reg_vdd = devm_regulator_get(dev, "vdd");
+	if (IS_ERR(db->reg_vdd))
+		return dev_err_probe(dev, PTR_ERR(db->reg_vdd),
+				     "Failed to get vdd supply\n");
+
+	db->reg_elvdd = devm_regulator_get_optional(dev, "elvdd");
+	if (IS_ERR(db->reg_elvdd))
+		db->reg_elvdd = NULL;
+
+	db->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(db->reset)) {
+		ret = PTR_ERR(db->reset);
+		return dev_err_probe(dev, ret, "no RESET GPIO\n");
+	}
+
+	db->enable = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
+	if (IS_ERR(db->enable)) {
+		ret = PTR_ERR(db->enable);
+		return dev_err_probe(dev, ret, "cannot get ENABLE GPIO\n");
+	}
+
+	ret = mipi_dbi_spi_init(spi, &db->dbi, NULL);
+	if (ret)
+		return dev_err_probe(dev, ret, "MIPI DBI init failed\n");
+
+	ret = drm_of_get_dsi_bus(dev, &dsi_host, &info);
+	if (ret)
+		return dev_err_probe(dev, ret, "Error attaching DSI bus\n");
+
+	db->dsi_dev = devm_mipi_dsi_device_register_full(dev, dsi_host, &info);
+	if (IS_ERR(db->dsi_dev)) {
+		dev_err(dev, "failed to register dsi device: %ld\n",
+			PTR_ERR(db->dsi_dev));
+		ret = PTR_ERR(db->dsi_dev);
+	}
+
+	db->dsi_dev->lanes = 2;
+	db->dsi_dev->format = MIPI_DSI_FMT_RGB888;
+	db->dsi_dev->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
+			  MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_NO_EOT_PACKET;
+
+	drm_panel_init(&db->panel, dev, db->panel_info->panel_funcs,
+		       DRM_MODE_CONNECTOR_DSI);
+
+	if (db->panel_info->backlight_register != NULL) {
+		ret = db->panel_info->backlight_register(db);
+		if (ret < 0)
+			return ret;
+	}
+
+	drm_panel_add(&db->panel);
+
+	ret = devm_mipi_dsi_attach(dev, db->dsi_dev);
+	if (ret < 0) {
+		dev_err(dev, "mipi_dsi_attach failed: %d\n", ret);
+		drm_panel_remove(&db->panel);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void d53e6ea8966_remove(struct spi_device *spi)
+{
+	struct d53e6ea8966 *db = spi_get_drvdata(spi);
+
+	drm_panel_remove(&db->panel);
+}
+
+static const struct drm_display_mode ams495qa01_modes[] = {
+	{ /* 60hz */
+		.clock = 33500,
+		.hdisplay = 960,
+		.hsync_start = 960 + 10,
+		.hsync_end = 960 + 10 + 2,
+		.htotal = 960 + 10 + 2 + 10,
+		.vdisplay = 544,
+		.vsync_start = 544 + 10,
+		.vsync_end = 544 + 10 + 2,
+		.vtotal = 544 + 10 + 2 + 10,
+		.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
+		.type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
+		},
+	{ /* 50hz */
+		.clock = 27800,
+		.hdisplay = 960,
+		.hsync_start = 960 + 10,
+		.hsync_end = 960 + 10 + 2,
+		.htotal = 960 + 10 + 2 + 10,
+		.vdisplay = 544,
+		.vsync_start = 544 + 10,
+		.vsync_end = 544 + 10 + 2,
+		.vtotal = 544 + 10 + 2 + 10,
+		.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
+		.type = DRM_MODE_TYPE_DRIVER,
+	},
+};
+
+static const struct d53e6ea8966_panel_info ams495qa01_info = {
+	.display_modes = ams495qa01_modes,
+	.num_modes = ARRAY_SIZE(ams495qa01_modes),
+	.width_mm = 117,
+	.height_mm = 74,
+	.bus_flags = DRM_BUS_FLAG_DE_LOW | DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE,
+	.panel_funcs = &ams495qa01_panel_funcs,
+	.backlight_register = ams495qa01_backlight_register,
+};
+
+static const struct of_device_id d53e6ea8966_match[] = {
+	{ .compatible = "samsung,ams495qa01", .data = &ams495qa01_info },
+	{},
+};
+MODULE_DEVICE_TABLE(of, d53e6ea8966_match);
+
+static const struct spi_device_id d53e6ea8966_ids[] = {
+	{ "ams495qa01", 0 },
+	{},
+};
+MODULE_DEVICE_TABLE(spi, d53e6ea8966_ids);
+
+static struct spi_driver d53e6ea8966_driver = {
+	.driver		= {
+		.name	= "d53e6ea8966-panel",
+		.of_match_table = d53e6ea8966_match,
+	},
+	.id_table	= d53e6ea8966_ids,
+	.probe		= d53e6ea8966_probe,
+	.remove		= d53e6ea8966_remove,
+};
+module_spi_driver(d53e6ea8966_driver);
+
+MODULE_AUTHOR("Chris Morgan <macromorgan@hotmail.com>");
+MODULE_DESCRIPTION("Magnachip d53e6ea8966 panel driver");
+MODULE_LICENSE("GPL");
-- 
2.34.1

[PATCH V5 3/4] drm/panel: Add Magnachip D53E6EA8966 Panel Driver

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Support Magnachip D53E6EA8966 based panels such as the Samsung
AMS495QA01 panel as found on the Anbernic RG503. Note this driver
supports only the AMS495QA01 today which receives video signals via DSI,
however it receives commands via 3-wire SPI.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
---
 drivers/gpu/drm/panel/Kconfig                 |  10 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 .../drm/panel/panel-magnachip-d53e6ea8966.c   | 515 ++++++++++++++++++
 3 files changed, 526 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index a582ddd583c2..1f81fe8a2f8a 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -288,6 +288,16 @@ config DRM_PANEL_LG_LG4573
 	  Say Y here if you want to enable support for LG4573 RGB panel.
 	  To compile this driver as a module, choose M here.
 
+config DRM_PANEL_MAGNACHIP_D53E6EA8966
+	tristate "Magnachip D53E6EA8966 DSI panel"
+	depends on OF && SPI
+	depends on DRM_MIPI_DSI
+	select DRM_MIPI_DBI
+	help
+	  DRM panel driver for the Samsung AMS495QA01 panel controlled
+	  with the Magnachip D53E6EA8966 panel IC. This panel receives
+	  video data via DSI but commands via 3-Wire 9-bit SPI.
+
 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 34e717382dbb..7c09cd480c69 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK050H3146W) += panel-leadtek-ltk050h3146w.o
 obj-$(CONFIG_DRM_PANEL_LEADTEK_LTK500HD1829) += panel-leadtek-ltk500hd1829.o
 obj-$(CONFIG_DRM_PANEL_LG_LB035Q02) += panel-lg-lb035q02.o
 obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o
+obj-$(CONFIG_DRM_PANEL_MAGNACHIP_D53E6EA8966) += panel-magnachip-d53e6ea8966.o
 obj-$(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-magnachip-d53e6ea8966.c b/drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c
new file mode 100644
index 000000000000..c1b80f2f296c
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-magnachip-d53e6ea8966.c
@@ -0,0 +1,515 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Magnachip d53e6ea8966 MIPI-DSI panel driver
+ * Copyright (C) 2022 Chris Morgan
+ */
+
+#include <drm/drm_mipi_dbi.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/media-bus-format.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_graph.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+
+#include <video/mipi_display.h>
+
+/* Forward declaration for use in backlight function */
+struct d53e6ea8966;
+
+/* Panel info, unique to each panel */
+struct d53e6ea8966_panel_info {
+	/** @display_modes: the supported display modes */
+	const struct drm_display_mode *display_modes;
+	/** @num_modes: the number of supported display modes */
+	unsigned int num_modes;
+	/** @width_mm: panel width in mm */
+	u16 width_mm;
+	/** @height_mm: panel height in mm */
+	u16 height_mm;
+	/** @bus_flags: drm bus flags for panel */
+	u32 bus_flags;
+	/** @panel_funcs: panel functions for panel */
+	const struct drm_panel_funcs *panel_funcs;
+	/** @backlight: panel backlight registration or NULL */
+	int (*backlight_register)(struct d53e6ea8966 *db);
+};
+
+struct d53e6ea8966 {
+	/** @dev: the container device */
+	struct device *dev;
+	/** @dbi: the DBI bus abstraction handle */
+	struct mipi_dbi dbi;
+	/** @panel: the DRM panel instance for this device */
+	struct drm_panel panel;
+	/** @reset: reset GPIO line */
+	struct gpio_desc *reset;
+	/** @enable: enable GPIO line */
+	struct gpio_desc *enable;
+	/** @reg_vdd: VDD supply regulator for panel logic */
+	struct regulator *reg_vdd;
+	/** @reg_elvdd: ELVDD supply regulator for panel display */
+	struct regulator *reg_elvdd;
+	/** @dsi_dev: DSI child device (panel) */
+	struct mipi_dsi_device *dsi_dev;
+	/** @bl_dev: pseudo-backlight device for oled panel */
+	struct backlight_device *bl_dev;
+	/** @panel_info: struct containing panel timing and info */
+	const struct d53e6ea8966_panel_info *panel_info;
+};
+
+#define NUM_GAMMA_LEVELS	16
+#define GAMMA_TABLE_COUNT	23
+#define MAX_BRIGHTNESS		(NUM_GAMMA_LEVELS - 1)
+
+#define MCS_ELVSS_ON			0xb1
+#define MCS_TEMP_SWIRE			0xb2
+#define MCS_PASSWORD_0			0xf0
+#define MCS_PASSWORD_1			0xf1
+#define MCS_ANALOG_PWR_CTL_0		0xf4
+#define MCS_ANALOG_PWR_CTL_1		0xf5
+#define MCS_GTCON_SET			0xf7
+#define MCS_GATELESS_SIGNAL_SET		0xf8
+#define MCS_SET_GAMMA			0xf9
+
+static inline struct d53e6ea8966 *to_d53e6ea8966(struct drm_panel *panel)
+{
+	return container_of(panel, struct d53e6ea8966, panel);
+}
+
+/* Table of gamma values provided in datasheet */
+static u8 ams495qa01_gamma[NUM_GAMMA_LEVELS][GAMMA_TABLE_COUNT] = {
+	{0x01, 0x79, 0x78, 0x8d, 0xd9, 0xdf, 0xd5, 0xcb, 0xcf, 0xc5,
+	 0xe5, 0xe0, 0xe4, 0xdc, 0xb8, 0xd4, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x7d, 0x7c, 0x92, 0xd7, 0xdd, 0xd2, 0xcb, 0xd0, 0xc6,
+	 0xe5, 0xe1, 0xe3, 0xda, 0xbd, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x7f, 0x7e, 0x95, 0xd7, 0xde, 0xd2, 0xcb, 0xcf, 0xc5,
+	 0xe5, 0xe3, 0xe3, 0xda, 0xbf, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x82, 0x81, 0x99, 0xd6, 0xdd, 0xd1, 0xca, 0xcf, 0xc3,
+	 0xe4, 0xe3, 0xe3, 0xda, 0xc2, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x84, 0x83, 0x9b, 0xd7, 0xde, 0xd2, 0xc8, 0xce, 0xc2,
+	 0xe4, 0xe3, 0xe2, 0xd9, 0xc3, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x87, 0x86, 0x9f, 0xd6, 0xdd, 0xd1, 0xc7, 0xce, 0xc1,
+	 0xe4, 0xe3, 0xe2, 0xd9, 0xc6, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x89, 0x89, 0xa2, 0xd5, 0xdb, 0xcf, 0xc8, 0xcf, 0xc2,
+	 0xe3, 0xe3, 0xe1, 0xd9, 0xc7, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x8b, 0x8b, 0xa5, 0xd5, 0xdb, 0xcf, 0xc7, 0xce, 0xc0,
+	 0xe3, 0xe3, 0xe1, 0xd8, 0xc7, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x8d, 0x8d, 0xa7, 0xd5, 0xdb, 0xcf, 0xc6, 0xce, 0xc0,
+	 0xe4, 0xe4, 0xe1, 0xd7, 0xc8, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x8f, 0x8f, 0xaa, 0xd4, 0xdb, 0xce, 0xc6, 0xcd, 0xbf,
+	 0xe3, 0xe3, 0xe1, 0xd7, 0xca, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x91, 0x91, 0xac, 0xd3, 0xda, 0xce, 0xc5, 0xcd, 0xbe,
+	 0xe3, 0xe3, 0xe0, 0xd7, 0xca, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x93, 0x93, 0xaf, 0xd3, 0xda, 0xcd, 0xc5, 0xcd, 0xbe,
+	 0xe2, 0xe3, 0xdf, 0xd6, 0xca, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x95, 0x95, 0xb1, 0xd2, 0xd9, 0xcc, 0xc4, 0xcd, 0xbe,
+	 0xe2, 0xe3, 0xdf, 0xd7, 0xcc, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x99, 0x99, 0xb6, 0xd1, 0xd9, 0xcc, 0xc3, 0xcb, 0xbc,
+	 0xe2, 0xe4, 0xdf, 0xd6, 0xcc, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x9c, 0x9c, 0xba, 0xd0, 0xd8, 0xcb, 0xc3, 0xcb, 0xbb,
+	 0xe2, 0xe4, 0xdf, 0xd6, 0xce, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+	{0x01, 0x9f, 0x9f, 0xbe, 0xcf, 0xd7, 0xc9, 0xc2, 0xcb, 0xbb,
+	 0xe1, 0xe3, 0xde, 0xd6, 0xd0, 0xd3, 0xfa, 0xed, 0xe6, 0x2f,
+	 0x00, 0x2f},
+};
+
+/*
+ * Table of elvss values provided in datasheet and corresponds to
+ * gamma values.
+ */
+static u8 ams495qa01_elvss[NUM_GAMMA_LEVELS] = {
+	0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x15,
+	0x15, 0x15, 0x14, 0x14, 0x13, 0x12,
+};
+
+static int ams495qa01_update_gamma(struct mipi_dbi *dbi, u32 brightness)
+{
+	u32 tmp = brightness;
+
+	mipi_dbi_command_buf(dbi, MCS_SET_GAMMA, ams495qa01_gamma[tmp],
+			     ARRAY_SIZE(ams495qa01_gamma[tmp]));
+	mipi_dbi_command(dbi, MCS_SET_GAMMA, 0x00);
+
+	/* Undocumented command */
+	mipi_dbi_command(dbi, 0x26, 0x00);
+
+	mipi_dbi_command(dbi, MCS_TEMP_SWIRE, ams495qa01_elvss[tmp]);
+
+	return 0;
+}
+
+static int ams495qa01_prepare(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	struct mipi_dbi *dbi = &db->dbi;
+	int ret;
+
+	/* Power up */
+	ret = regulator_enable(db->reg_vdd);
+	if (ret) {
+		dev_err(db->dev, "failed to enable vdd regulator: %d\n", ret);
+		return ret;
+	}
+
+	if (db->reg_elvdd) {
+		ret = regulator_enable(db->reg_elvdd);
+		if (ret) {
+			dev_err(db->dev,
+				"failed to enable elvdd regulator: %d\n", ret);
+			regulator_disable(db->reg_vdd);
+			return ret;
+		}
+	}
+
+	/* Enable */
+	if (db->enable)
+		gpiod_set_value_cansleep(db->enable, 1);
+
+	msleep(50);
+
+	/* Reset */
+	gpiod_set_value_cansleep(db->reset, 1);
+	usleep_range(1000, 5000);
+	gpiod_set_value_cansleep(db->reset, 0);
+	msleep(20);
+
+	/* Panel Init Sequence */
+
+	mipi_dbi_command(dbi, MCS_PASSWORD_0, 0x5a, 0x5a);
+	mipi_dbi_command(dbi, MCS_PASSWORD_1, 0x5a, 0x5a);
+	/* Undocumented commands */
+	mipi_dbi_command(dbi, 0xb0, 0x02);
+	mipi_dbi_command(dbi, 0xf3, 0x3b);
+
+	mipi_dbi_command(dbi, MCS_ANALOG_PWR_CTL_0, 0x33, 0x42, 0x00, 0x08);
+	mipi_dbi_command(dbi, MCS_ANALOG_PWR_CTL_1, 0x00, 0x06, 0x26, 0x35, 0x03);
+
+	/* Undocumented commands */
+	mipi_dbi_command(dbi, 0xf6, 0x02);
+	mipi_dbi_command(dbi, 0xc6, 0x0b, 0x00, 0x00, 0x3c, 0x00, 0x22,
+			 0x00, 0x00, 0x00, 0x00);
+
+	mipi_dbi_command(dbi, MCS_GTCON_SET, 0x20);
+	mipi_dbi_command(dbi, MCS_TEMP_SWIRE, 0x06, 0x06, 0x06, 0x06);
+	mipi_dbi_command(dbi, MCS_ELVSS_ON, 0x07, 0x00, 0x10);
+	mipi_dbi_command(dbi, MCS_GATELESS_SIGNAL_SET, 0x7f, 0x7a,
+			 0x89, 0x67, 0x26, 0x38, 0x00, 0x00, 0x09,
+			 0x67, 0x70, 0x88, 0x7a, 0x76, 0x05, 0x09,
+			 0x23, 0x23, 0x23);
+
+	/* Undocumented commands */
+	mipi_dbi_command(dbi, 0xb5, 0xff, 0xef, 0x35, 0x42, 0x0d, 0xd7,
+			 0xff, 0x07, 0xff, 0xff, 0xfd, 0x00, 0x01,
+			 0xff, 0x05, 0x12, 0x0f, 0xff, 0xff, 0xff,
+			 0xff);
+	mipi_dbi_command(dbi, 0xb4, 0x15);
+	mipi_dbi_command(dbi, 0xb3, 0x00);
+
+	ams495qa01_update_gamma(dbi, MAX_BRIGHTNESS);
+
+	return 0;
+}
+
+static int ams495qa01_enable(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	struct mipi_dbi *dbi = &db->dbi;
+
+	mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
+	msleep(200);
+	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
+	usleep_range(10000, 15000);
+
+	return 0;
+}
+
+static int ams495qa01_disable(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	struct mipi_dbi *dbi = &db->dbi;
+
+	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_OFF);
+	msleep(20);
+	mipi_dbi_command(dbi, MIPI_DCS_ENTER_SLEEP_MODE);
+	msleep(100);
+
+	return 0;
+}
+
+static int ams495qa01_unprepare(struct drm_panel *panel)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+
+	if (db->enable)
+		gpiod_set_value_cansleep(db->enable, 0);
+
+	gpiod_set_value_cansleep(db->reset, 1);
+
+	if (db->reg_elvdd)
+		regulator_disable(db->reg_elvdd);
+
+	regulator_disable(db->reg_vdd);
+	msleep(100);
+
+	return 0;
+}
+
+static int ams495qa01_get_modes(struct drm_panel *panel,
+				struct drm_connector *connector)
+{
+	struct d53e6ea8966 *db = to_d53e6ea8966(panel);
+	const struct d53e6ea8966_panel_info *panel_info = db->panel_info;
+	struct drm_display_mode *mode;
+	static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+	unsigned int i;
+
+	for (i = 0; i < panel_info->num_modes; i++) {
+		mode = drm_mode_duplicate(connector->dev,
+					  &panel_info->display_modes[i]);
+		if (!mode)
+			return -ENOMEM;
+
+		drm_mode_set_name(mode);
+		drm_mode_probed_add(connector, mode);
+	}
+
+	connector->display_info.bpc = 8;
+	connector->display_info.width_mm = panel_info->width_mm;
+	connector->display_info.height_mm = panel_info->height_mm;
+	connector->display_info.bus_flags = panel_info->bus_flags;
+
+	drm_display_info_set_bus_formats(&connector->display_info,
+					 &bus_format, 1);
+
+	return 1;
+}
+
+static const struct drm_panel_funcs ams495qa01_panel_funcs = {
+	.disable = ams495qa01_disable,
+	.enable = ams495qa01_enable,
+	.get_modes = ams495qa01_get_modes,
+	.prepare = ams495qa01_prepare,
+	.unprepare = ams495qa01_unprepare,
+};
+
+static int ams495qa01_set_brightness(struct backlight_device *bd)
+{
+	struct d53e6ea8966 *db = bl_get_data(bd);
+	struct mipi_dbi *dbi = &db->dbi;
+	int brightness = bd->props.brightness;
+
+	ams495qa01_update_gamma(dbi, brightness);
+
+	return 0;
+}
+
+static const struct backlight_ops ams495qa01_backlight_ops = {
+	.update_status	= ams495qa01_set_brightness,
+};
+
+static int ams495qa01_backlight_register(struct d53e6ea8966 *db)
+{
+	struct backlight_properties props = {
+		.type		= BACKLIGHT_RAW,
+		.brightness	= MAX_BRIGHTNESS,
+		.max_brightness = MAX_BRIGHTNESS,
+	};
+	struct device *dev = db->dev;
+	int ret = 0;
+
+	db->bl_dev = devm_backlight_device_register(dev, "panel", dev, db,
+						     &ams495qa01_backlight_ops,
+						     &props);
+	if (IS_ERR(db->bl_dev)) {
+		ret = PTR_ERR(db->bl_dev);
+		dev_err(dev, "error registering backlight device (%d)\n", ret);
+	}
+
+	return ret;
+}
+
+static int d53e6ea8966_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct mipi_dsi_host *dsi_host;
+	struct d53e6ea8966 *db;
+	int ret;
+	struct mipi_dsi_device_info info = {
+		.type = "d53e6ea8966",
+		.channel = 0,
+		.node = NULL,
+	};
+
+	db = devm_kzalloc(dev, sizeof(*db), GFP_KERNEL);
+	if (!db)
+		return -ENOMEM;
+
+	spi_set_drvdata(spi, db);
+
+	db->dev = dev;
+
+	db->panel_info = of_device_get_match_data(dev);
+	if (!db->panel_info)
+		return -EINVAL;
+
+	db->reg_vdd = devm_regulator_get(dev, "vdd");
+	if (IS_ERR(db->reg_vdd))
+		return dev_err_probe(dev, PTR_ERR(db->reg_vdd),
+				     "Failed to get vdd supply\n");
+
+	db->reg_elvdd = devm_regulator_get_optional(dev, "elvdd");
+	if (IS_ERR(db->reg_elvdd))
+		db->reg_elvdd = NULL;
+
+	db->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(db->reset)) {
+		ret = PTR_ERR(db->reset);
+		return dev_err_probe(dev, ret, "no RESET GPIO\n");
+	}
+
+	db->enable = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
+	if (IS_ERR(db->enable)) {
+		ret = PTR_ERR(db->enable);
+		return dev_err_probe(dev, ret, "cannot get ENABLE GPIO\n");
+	}
+
+	ret = mipi_dbi_spi_init(spi, &db->dbi, NULL);
+	if (ret)
+		return dev_err_probe(dev, ret, "MIPI DBI init failed\n");
+
+	ret = drm_of_get_dsi_bus(dev, &dsi_host, &info);
+	if (ret)
+		return dev_err_probe(dev, ret, "Error attaching DSI bus\n");
+
+	db->dsi_dev = devm_mipi_dsi_device_register_full(dev, dsi_host, &info);
+	if (IS_ERR(db->dsi_dev)) {
+		dev_err(dev, "failed to register dsi device: %ld\n",
+			PTR_ERR(db->dsi_dev));
+		ret = PTR_ERR(db->dsi_dev);
+	}
+
+	db->dsi_dev->lanes = 2;
+	db->dsi_dev->format = MIPI_DSI_FMT_RGB888;
+	db->dsi_dev->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
+			  MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_NO_EOT_PACKET;
+
+	drm_panel_init(&db->panel, dev, db->panel_info->panel_funcs,
+		       DRM_MODE_CONNECTOR_DSI);
+
+	if (db->panel_info->backlight_register != NULL) {
+		ret = db->panel_info->backlight_register(db);
+		if (ret < 0)
+			return ret;
+	}
+
+	drm_panel_add(&db->panel);
+
+	ret = devm_mipi_dsi_attach(dev, db->dsi_dev);
+	if (ret < 0) {
+		dev_err(dev, "mipi_dsi_attach failed: %d\n", ret);
+		drm_panel_remove(&db->panel);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void d53e6ea8966_remove(struct spi_device *spi)
+{
+	struct d53e6ea8966 *db = spi_get_drvdata(spi);
+
+	drm_panel_remove(&db->panel);
+}
+
+static const struct drm_display_mode ams495qa01_modes[] = {
+	{ /* 60hz */
+		.clock = 33500,
+		.hdisplay = 960,
+		.hsync_start = 960 + 10,
+		.hsync_end = 960 + 10 + 2,
+		.htotal = 960 + 10 + 2 + 10,
+		.vdisplay = 544,
+		.vsync_start = 544 + 10,
+		.vsync_end = 544 + 10 + 2,
+		.vtotal = 544 + 10 + 2 + 10,
+		.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
+		.type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
+		},
+	{ /* 50hz */
+		.clock = 27800,
+		.hdisplay = 960,
+		.hsync_start = 960 + 10,
+		.hsync_end = 960 + 10 + 2,
+		.htotal = 960 + 10 + 2 + 10,
+		.vdisplay = 544,
+		.vsync_start = 544 + 10,
+		.vsync_end = 544 + 10 + 2,
+		.vtotal = 544 + 10 + 2 + 10,
+		.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
+		.type = DRM_MODE_TYPE_DRIVER,
+	},
+};
+
+static const struct d53e6ea8966_panel_info ams495qa01_info = {
+	.display_modes = ams495qa01_modes,
+	.num_modes = ARRAY_SIZE(ams495qa01_modes),
+	.width_mm = 117,
+	.height_mm = 74,
+	.bus_flags = DRM_BUS_FLAG_DE_LOW | DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE,
+	.panel_funcs = &ams495qa01_panel_funcs,
+	.backlight_register = ams495qa01_backlight_register,
+};
+
+static const struct of_device_id d53e6ea8966_match[] = {
+	{ .compatible = "samsung,ams495qa01", .data = &ams495qa01_info },
+	{},
+};
+MODULE_DEVICE_TABLE(of, d53e6ea8966_match);
+
+static const struct spi_device_id d53e6ea8966_ids[] = {
+	{ "ams495qa01", 0 },
+	{},
+};
+MODULE_DEVICE_TABLE(spi, d53e6ea8966_ids);
+
+static struct spi_driver d53e6ea8966_driver = {
+	.driver		= {
+		.name	= "d53e6ea8966-panel",
+		.of_match_table = d53e6ea8966_match,
+	},
+	.id_table	= d53e6ea8966_ids,
+	.probe		= d53e6ea8966_probe,
+	.remove		= d53e6ea8966_remove,
+};
+module_spi_driver(d53e6ea8966_driver);
+
+MODULE_AUTHOR("Chris Morgan <macromorgan@hotmail.com>");
+MODULE_DESCRIPTION("Magnachip d53e6ea8966 panel driver");
+MODULE_LICENSE("GPL");
-- 
2.34.1

Re: [PATCH V5 3/4] drm/panel: Add Magnachip D53E6EA8966 Panel Driver

[Linus Walleij]

Hi Chris,

looks good to me, just very minor nitpicks:

On Wed, Dec 14, 2022 at 7:06 PM Chris Morgan <macroalpha82@gmail.com> wrote:
>
> From: Chris Morgan <macromorgan@hotmail.com>
>
> Support Magnachip D53E6EA8966 based panels such as the Samsung
> AMS495QA01 panel as found on the Anbernic RG503. Note this driver
> supports only the AMS495QA01 today which receives video signals via DSI,
> however it receives commands via 3-wire SPI.

using DBI.

>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>

Is your Kconfig snippet missing:

        depends on BACKLIGHT_CLASS_DEVICE

?

> +#include <linux/of_device.h>
> +#include <linux/of_graph.h>

Not needed anymore, right?

With these fixed:
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij

Re: [PATCH V5 3/4] drm/panel: Add Magnachip D53E6EA8966 Panel Driver

[Linus Walleij]

Hi Chris,

looks good to me, just very minor nitpicks:

On Wed, Dec 14, 2022 at 7:06 PM Chris Morgan <macroalpha82@gmail.com> wrote:
>
> From: Chris Morgan <macromorgan@hotmail.com>
>
> Support Magnachip D53E6EA8966 based panels such as the Samsung
> AMS495QA01 panel as found on the Anbernic RG503. Note this driver
> supports only the AMS495QA01 today which receives video signals via DSI,
> however it receives commands via 3-wire SPI.

using DBI.

>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>

Is your Kconfig snippet missing:

        depends on BACKLIGHT_CLASS_DEVICE

?

> +#include <linux/of_device.h>
> +#include <linux/of_graph.h>

Not needed anymore, right?

With these fixed:
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij

[PATCH V4 4/4] arm64: dts: rockchip: add display to RG503

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Add Samsung AMS495QA01 panel to RG503.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
---
 .../dts/rockchip/rk3566-anbernic-rg503.dts    | 55 +++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3566-anbernic-rg503.dts b/arch/arm64/boot/dts/rockchip/rk3566-anbernic-rg503.dts
index 5dafcc86296b..b4b2df821cba 100644
--- a/arch/arm64/boot/dts/rockchip/rk3566-anbernic-rg503.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3566-anbernic-rg503.dts
@@ -47,6 +47,21 @@ gpio_spi: spi {
 		mosi-gpios = <&gpio4 RK_PB0 GPIO_ACTIVE_HIGH>;
 		cs-gpios = <&gpio4 RK_PA7 GPIO_ACTIVE_HIGH>;
 		num-chipselects = <0>;
+
+		panel@0 {
+			compatible = "samsung,ams495qa01";
+			reg = <0>;
+			pinctrl-names = "default";
+			pinctrl-0 = <&lcd_reset>;
+			reset-gpios = <&gpio4 RK_PA0 GPIO_ACTIVE_LOW>;
+			vdd-supply = <&vcc_3v3>;
+
+			port {
+				mipi_in_panel: endpoint {
+					remote-endpoint = <&mipi_out_panel>;
+				};
+			};
+		};
 	};
 
 	/* Channels reversed for both headphones and speakers. */
@@ -94,6 +109,32 @@ &cru {
 	assigned-clock-rates = <1200000000>, <200000000>, <500000000>;
 };
 
+&dsi_dphy0 {
+	status = "okay";
+};
+
+&dsi0 {
+	status = "okay";
+
+	ports {
+		dsi0_in: port@0 {
+			reg = <0>;
+
+			dsi0_in_vp1: endpoint {
+				remote-endpoint = <&vp1_out_dsi0>;
+			};
+		};
+
+		dsi0_out: port@1 {
+			reg = <1>;
+
+			mipi_out_panel: endpoint {
+				remote-endpoint = <&mipi_in_panel>;
+			};
+		};
+	};
+};
+
 &gpio_keys_control {
 	button-a {
 		gpios = <&gpio3 RK_PC1 GPIO_ACTIVE_LOW>;
@@ -146,6 +187,13 @@ spk_amp_enable_h: spk-amp-enable-h {
 		};
 	};
 
+	gpio-lcd {
+		lcd_reset: lcd-reset {
+			rockchip,pins =
+				<4 RK_PA0 RK_FUNC_GPIO &pcfg_pull_none>;
+		};
+	};
+
 	gpio-spi {
 		spi_pins: spi-pins {
 			rockchip,pins =
@@ -164,3 +212,10 @@ rk817_charger: charger {
 		rockchip,sleep-filter-current-microamp = <100000>;
 	};
 };
+
+&vp1 {
+	vp1_out_dsi0: endpoint@ROCKCHIP_VOP2_EP_MIPI0 {
+		reg = <ROCKCHIP_VOP2_EP_MIPI0>;
+		remote-endpoint = <&dsi0_in_vp1>;
+	};
+};
-- 
2.34.1

[PATCH V4 4/4] arm64: dts: rockchip: add display to RG503

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Add Samsung AMS495QA01 panel to RG503.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
---
 .../dts/rockchip/rk3566-anbernic-rg503.dts    | 55 +++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3566-anbernic-rg503.dts b/arch/arm64/boot/dts/rockchip/rk3566-anbernic-rg503.dts
index 5dafcc86296b..b4b2df821cba 100644
--- a/arch/arm64/boot/dts/rockchip/rk3566-anbernic-rg503.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3566-anbernic-rg503.dts
@@ -47,6 +47,21 @@ gpio_spi: spi {
 		mosi-gpios = <&gpio4 RK_PB0 GPIO_ACTIVE_HIGH>;
 		cs-gpios = <&gpio4 RK_PA7 GPIO_ACTIVE_HIGH>;
 		num-chipselects = <0>;
+
+		panel@0 {
+			compatible = "samsung,ams495qa01";
+			reg = <0>;
+			pinctrl-names = "default";
+			pinctrl-0 = <&lcd_reset>;
+			reset-gpios = <&gpio4 RK_PA0 GPIO_ACTIVE_LOW>;
+			vdd-supply = <&vcc_3v3>;
+
+			port {
+				mipi_in_panel: endpoint {
+					remote-endpoint = <&mipi_out_panel>;
+				};
+			};
+		};
 	};
 
 	/* Channels reversed for both headphones and speakers. */
@@ -94,6 +109,32 @@ &cru {
 	assigned-clock-rates = <1200000000>, <200000000>, <500000000>;
 };
 
+&dsi_dphy0 {
+	status = "okay";
+};
+
+&dsi0 {
+	status = "okay";
+
+	ports {
+		dsi0_in: port@0 {
+			reg = <0>;
+
+			dsi0_in_vp1: endpoint {
+				remote-endpoint = <&vp1_out_dsi0>;
+			};
+		};
+
+		dsi0_out: port@1 {
+			reg = <1>;
+
+			mipi_out_panel: endpoint {
+				remote-endpoint = <&mipi_in_panel>;
+			};
+		};
+	};
+};
+
 &gpio_keys_control {
 	button-a {
 		gpios = <&gpio3 RK_PC1 GPIO_ACTIVE_LOW>;
@@ -146,6 +187,13 @@ spk_amp_enable_h: spk-amp-enable-h {
 		};
 	};
 
+	gpio-lcd {
+		lcd_reset: lcd-reset {
+			rockchip,pins =
+				<4 RK_PA0 RK_FUNC_GPIO &pcfg_pull_none>;
+		};
+	};
+
 	gpio-spi {
 		spi_pins: spi-pins {
 			rockchip,pins =
@@ -164,3 +212,10 @@ rk817_charger: charger {
 		rockchip,sleep-filter-current-microamp = <100000>;
 	};
 };
+
+&vp1 {
+	vp1_out_dsi0: endpoint@ROCKCHIP_VOP2_EP_MIPI0 {
+		reg = <ROCKCHIP_VOP2_EP_MIPI0>;
+		remote-endpoint = <&dsi0_in_vp1>;
+	};
+};
-- 
2.34.1