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* [PATCH 0/2] Add support of Lontium lt8912 MIPI to HDMI bridge
@ 2021-01-24 15:08 ` Adrien Grassein
  0 siblings, 0 replies; 10+ messages in thread
From: Adrien Grassein @ 2021-01-24 15:08 UTC (permalink / raw)
  Cc: airlied, daniel, robh+dt, a.hajda, narmstrong, Laurent.pinchart,
	jonas, jernej.skrabec, dri-devel, devicetree, linux-kernel,
	Adrien Grassein

Hello,

this patch set adds the support of the Lontium lt8912 MIPI to HDMI
bridge in the kernel.

It's only support the video part, not the audio part yet
since I don't have the datasheet of this component.
I get the current i2c configuration from Digi and
Boundary drivers.
Developed using the DB_DSIHD board from BoundaryDevices.

Thanks,
Adrien Grassein

Adrien Grassein (2):
  dt-bindings: display: bridge: Add documentation for LT8912
  drm/bridge: Introduce LT8912 DSI to HDMI bridge

 .../display/bridge/lontium,lt8912.yaml        |  92 +++
 MAINTAINERS                                   |   6 +
 drivers/gpu/drm/bridge/Kconfig                |  14 +
 drivers/gpu/drm/bridge/Makefile               |   1 +
 drivers/gpu/drm/bridge/lontium-lt8912.c       | 749 ++++++++++++++++++
 5 files changed, 862 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
 create mode 100644 drivers/gpu/drm/bridge/lontium-lt8912.c

-- 
2.25.1


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH 0/2] Add support of Lontium lt8912 MIPI to HDMI bridge
@ 2021-01-24 15:08 ` Adrien Grassein
  0 siblings, 0 replies; 10+ messages in thread
From: Adrien Grassein @ 2021-01-24 15:08 UTC (permalink / raw)
  Cc: devicetree, jernej.skrabec, narmstrong, airlied, jonas,
	linux-kernel, dri-devel, a.hajda, robh+dt, Laurent.pinchart,
	Adrien Grassein

Hello,

this patch set adds the support of the Lontium lt8912 MIPI to HDMI
bridge in the kernel.

It's only support the video part, not the audio part yet
since I don't have the datasheet of this component.
I get the current i2c configuration from Digi and
Boundary drivers.
Developed using the DB_DSIHD board from BoundaryDevices.

Thanks,
Adrien Grassein

Adrien Grassein (2):
  dt-bindings: display: bridge: Add documentation for LT8912
  drm/bridge: Introduce LT8912 DSI to HDMI bridge

 .../display/bridge/lontium,lt8912.yaml        |  92 +++
 MAINTAINERS                                   |   6 +
 drivers/gpu/drm/bridge/Kconfig                |  14 +
 drivers/gpu/drm/bridge/Makefile               |   1 +
 drivers/gpu/drm/bridge/lontium-lt8912.c       | 749 ++++++++++++++++++
 5 files changed, 862 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
 create mode 100644 drivers/gpu/drm/bridge/lontium-lt8912.c

-- 
2.25.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH 1/2] dt-bindings: display: bridge: Add documentation for LT8912
  2021-01-24 15:08 ` Adrien Grassein
@ 2021-01-24 15:08   ` Adrien Grassein
  -1 siblings, 0 replies; 10+ messages in thread
From: Adrien Grassein @ 2021-01-24 15:08 UTC (permalink / raw)
  Cc: airlied, daniel, robh+dt, a.hajda, narmstrong, Laurent.pinchart,
	jonas, jernej.skrabec, dri-devel, devicetree, linux-kernel,
	Adrien Grassein

Lontium LT8912 is a DSI to HDMI bridge.

Signed-off-by: Adrien Grassein <adrien.grassein@gmail.com>
---
 .../display/bridge/lontium,lt8912.yaml        | 92 +++++++++++++++++++
 MAINTAINERS                                   |  5 +
 2 files changed, 97 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml

diff --git a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
new file mode 100644
index 000000000000..ed1a6ddaab2f
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
@@ -0,0 +1,92 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/bridge/lontium,lt8912.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Lontium LT8912 MIPI to HDMI Bridge
+
+maintainers:
+  - Adrien Grassein <adrien.grassein@gmail.com>
+
+description: |
+  The LT8912 is a bridge device which convert DSI to HDMI
+
+properties:
+  compatible:
+    enum:
+      - lontium,lt8912
+
+  reg:
+    maxItems: 1
+
+  ddc-i2c-bus:
+    maxItems: 1
+    description: i2c bus used to read EDID of the connected display.
+
+  dsi-lanes:
+    maxItems: 1
+    description: dsi lanes count interconnected with lt8912.
+
+  reset-gpios:
+    maxItems: 1
+    description: GPIO connected to active high RESET pin.
+
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+
+    properties:
+      port@0:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Primary MIPI port-1 for MIPI input
+
+    required:
+      - port@0
+
+required:
+  - compatible
+  - ddc-i2c-bus
+  - dsi-lanes
+  - reg
+  - reset-gpios
+  - ports
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    i2c4 {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      hdmi-bridge@48 {
+        compatible = "lontium,lt8912";
+        reg = <0x48>;
+        reset-gpios = <&max7323 0 GPIO_ACTIVE_LOW>;
+        dsi-lanes = <4>;
+        ddc-i2c-bus = <&ddc_i2c_bus>;
+
+        ports {
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          port@0 {
+            reg = <0>;
+
+            hdmi_out_in: endpoint {
+              remote-endpoint = <&mipi_dsi_out>;
+            };
+          };
+        };
+      };
+    };
+
+    ddc_i2c_bus: i2c5 {
+      #address-cells = <1>;
+      #size-cells = <0>;
+    };
+
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index 5aa18cbfb883..01e7e356bfac 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10472,6 +10472,11 @@ S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git
 F:	drivers/hid/hid-lg-g15.c
 
+LONTIUM LT8912 MIPI TO HDMI BRIDGE
+M:	Adrien Grassein <adrien.grassein@gmail.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
+
 LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
 M:	Sathya Prakash <sathya.prakash@broadcom.com>
 M:	Sreekanth Reddy <sreekanth.reddy@broadcom.com>
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH 1/2] dt-bindings: display: bridge: Add documentation for LT8912
@ 2021-01-24 15:08   ` Adrien Grassein
  0 siblings, 0 replies; 10+ messages in thread
From: Adrien Grassein @ 2021-01-24 15:08 UTC (permalink / raw)
  Cc: devicetree, jernej.skrabec, narmstrong, airlied, jonas,
	linux-kernel, dri-devel, a.hajda, robh+dt, Laurent.pinchart,
	Adrien Grassein

Lontium LT8912 is a DSI to HDMI bridge.

Signed-off-by: Adrien Grassein <adrien.grassein@gmail.com>
---
 .../display/bridge/lontium,lt8912.yaml        | 92 +++++++++++++++++++
 MAINTAINERS                                   |  5 +
 2 files changed, 97 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml

diff --git a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
new file mode 100644
index 000000000000..ed1a6ddaab2f
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
@@ -0,0 +1,92 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/bridge/lontium,lt8912.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Lontium LT8912 MIPI to HDMI Bridge
+
+maintainers:
+  - Adrien Grassein <adrien.grassein@gmail.com>
+
+description: |
+  The LT8912 is a bridge device which convert DSI to HDMI
+
+properties:
+  compatible:
+    enum:
+      - lontium,lt8912
+
+  reg:
+    maxItems: 1
+
+  ddc-i2c-bus:
+    maxItems: 1
+    description: i2c bus used to read EDID of the connected display.
+
+  dsi-lanes:
+    maxItems: 1
+    description: dsi lanes count interconnected with lt8912.
+
+  reset-gpios:
+    maxItems: 1
+    description: GPIO connected to active high RESET pin.
+
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+
+    properties:
+      port@0:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Primary MIPI port-1 for MIPI input
+
+    required:
+      - port@0
+
+required:
+  - compatible
+  - ddc-i2c-bus
+  - dsi-lanes
+  - reg
+  - reset-gpios
+  - ports
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    i2c4 {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      hdmi-bridge@48 {
+        compatible = "lontium,lt8912";
+        reg = <0x48>;
+        reset-gpios = <&max7323 0 GPIO_ACTIVE_LOW>;
+        dsi-lanes = <4>;
+        ddc-i2c-bus = <&ddc_i2c_bus>;
+
+        ports {
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          port@0 {
+            reg = <0>;
+
+            hdmi_out_in: endpoint {
+              remote-endpoint = <&mipi_dsi_out>;
+            };
+          };
+        };
+      };
+    };
+
+    ddc_i2c_bus: i2c5 {
+      #address-cells = <1>;
+      #size-cells = <0>;
+    };
+
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index 5aa18cbfb883..01e7e356bfac 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10472,6 +10472,11 @@ S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git
 F:	drivers/hid/hid-lg-g15.c
 
+LONTIUM LT8912 MIPI TO HDMI BRIDGE
+M:	Adrien Grassein <adrien.grassein@gmail.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
+
 LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
 M:	Sathya Prakash <sathya.prakash@broadcom.com>
 M:	Sreekanth Reddy <sreekanth.reddy@broadcom.com>
-- 
2.25.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH 1/2] dt-bindings: display: bridge: Add documentation for LT8912
  2021-01-24 15:08 ` Adrien Grassein
@ 2021-01-24 15:08   ` Adrien Grassein
  -1 siblings, 0 replies; 10+ messages in thread
From: Adrien Grassein @ 2021-01-24 15:08 UTC (permalink / raw)
  Cc: airlied, daniel, robh+dt, a.hajda, narmstrong, Laurent.pinchart,
	jonas, jernej.skrabec, dri-devel, devicetree, linux-kernel,
	Adrien Grassein

Lontium LT8912 is a DSI to HDMI bridge.

Signed-off-by: Adrien Grassein <adrien.grassein@gmail.com>
---
 .../display/bridge/lontium,lt8912.yaml        | 92 +++++++++++++++++++
 MAINTAINERS                                   |  5 +
 2 files changed, 97 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml

diff --git a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
new file mode 100644
index 000000000000..ed1a6ddaab2f
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
@@ -0,0 +1,92 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/bridge/lontium,lt8912.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Lontium LT8912 MIPI to HDMI Bridge
+
+maintainers:
+  - Adrien Grassein <adrien.grassein@gmail.com>
+
+description: |
+  The LT8912 is a bridge device which convert DSI to HDMI
+
+properties:
+  compatible:
+    enum:
+      - lontium,lt8912
+
+  reg:
+    maxItems: 1
+
+  ddc-i2c-bus:
+    maxItems: 1
+    description: i2c bus used to read EDID of the connected display.
+
+  dsi-lanes:
+    maxItems: 1
+    description: dsi lanes count interconnected with lt8912.
+
+  reset-gpios:
+    maxItems: 1
+    description: GPIO connected to active high RESET pin.
+
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+
+    properties:
+      port@0:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Primary MIPI port-1 for MIPI input
+
+    required:
+      - port@0
+
+required:
+  - compatible
+  - ddc-i2c-bus
+  - dsi-lanes
+  - reg
+  - reset-gpios
+  - ports
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    i2c4 {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      hdmi-bridge@48 {
+        compatible = "lontium,lt8912";
+        reg = <0x48>;
+        reset-gpios = <&max7323 0 GPIO_ACTIVE_LOW>;
+        dsi-lanes = <4>;
+        ddc-i2c-bus = <&ddc_i2c_bus>;
+
+        ports {
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          port@0 {
+            reg = <0>;
+
+            hdmi_out_in: endpoint {
+              remote-endpoint = <&mipi_dsi_out>;
+            };
+          };
+        };
+      };
+    };
+
+    ddc_i2c_bus: i2c5 {
+      #address-cells = <1>;
+      #size-cells = <0>;
+    };
+
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index 5aa18cbfb883..01e7e356bfac 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10472,6 +10472,11 @@ S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git
 F:	drivers/hid/hid-lg-g15.c
 
+LONTIUM LT8912 MIPI TO HDMI BRIDGE
+M:	Adrien Grassein <adrien.grassein@gmail.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
+
 LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
 M:	Sathya Prakash <sathya.prakash@broadcom.com>
 M:	Sreekanth Reddy <sreekanth.reddy@broadcom.com>
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH 1/2] dt-bindings: display: bridge: Add documentation for LT8912
@ 2021-01-24 15:08   ` Adrien Grassein
  0 siblings, 0 replies; 10+ messages in thread
From: Adrien Grassein @ 2021-01-24 15:08 UTC (permalink / raw)
  Cc: devicetree, jernej.skrabec, narmstrong, airlied, jonas,
	linux-kernel, dri-devel, a.hajda, robh+dt, Laurent.pinchart,
	Adrien Grassein

Lontium LT8912 is a DSI to HDMI bridge.

Signed-off-by: Adrien Grassein <adrien.grassein@gmail.com>
---
 .../display/bridge/lontium,lt8912.yaml        | 92 +++++++++++++++++++
 MAINTAINERS                                   |  5 +
 2 files changed, 97 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml

diff --git a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
new file mode 100644
index 000000000000..ed1a6ddaab2f
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
@@ -0,0 +1,92 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/bridge/lontium,lt8912.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Lontium LT8912 MIPI to HDMI Bridge
+
+maintainers:
+  - Adrien Grassein <adrien.grassein@gmail.com>
+
+description: |
+  The LT8912 is a bridge device which convert DSI to HDMI
+
+properties:
+  compatible:
+    enum:
+      - lontium,lt8912
+
+  reg:
+    maxItems: 1
+
+  ddc-i2c-bus:
+    maxItems: 1
+    description: i2c bus used to read EDID of the connected display.
+
+  dsi-lanes:
+    maxItems: 1
+    description: dsi lanes count interconnected with lt8912.
+
+  reset-gpios:
+    maxItems: 1
+    description: GPIO connected to active high RESET pin.
+
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+
+    properties:
+      port@0:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Primary MIPI port-1 for MIPI input
+
+    required:
+      - port@0
+
+required:
+  - compatible
+  - ddc-i2c-bus
+  - dsi-lanes
+  - reg
+  - reset-gpios
+  - ports
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    i2c4 {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      hdmi-bridge@48 {
+        compatible = "lontium,lt8912";
+        reg = <0x48>;
+        reset-gpios = <&max7323 0 GPIO_ACTIVE_LOW>;
+        dsi-lanes = <4>;
+        ddc-i2c-bus = <&ddc_i2c_bus>;
+
+        ports {
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          port@0 {
+            reg = <0>;
+
+            hdmi_out_in: endpoint {
+              remote-endpoint = <&mipi_dsi_out>;
+            };
+          };
+        };
+      };
+    };
+
+    ddc_i2c_bus: i2c5 {
+      #address-cells = <1>;
+      #size-cells = <0>;
+    };
+
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index 5aa18cbfb883..01e7e356bfac 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10472,6 +10472,11 @@ S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git
 F:	drivers/hid/hid-lg-g15.c
 
+LONTIUM LT8912 MIPI TO HDMI BRIDGE
+M:	Adrien Grassein <adrien.grassein@gmail.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
+
 LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
 M:	Sathya Prakash <sathya.prakash@broadcom.com>
 M:	Sreekanth Reddy <sreekanth.reddy@broadcom.com>
-- 
2.25.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH 2/2] drm/bridge: Introduce LT8912 DSI to HDMI bridge
  2021-01-24 15:08 ` Adrien Grassein
@ 2021-01-24 15:08   ` Adrien Grassein
  -1 siblings, 0 replies; 10+ messages in thread
From: Adrien Grassein @ 2021-01-24 15:08 UTC (permalink / raw)
  Cc: airlied, daniel, robh+dt, a.hajda, narmstrong, Laurent.pinchart,
	jonas, jernej.skrabec, dri-devel, devicetree, linux-kernel,
	Adrien Grassein

Lontium Lt8912 is a DSI to HDMI bridge.

Signed-off-by: Adrien Grassein <adrien.grassein@gmail.com>
---
 MAINTAINERS                             |   1 +
 drivers/gpu/drm/bridge/Kconfig          |  14 +
 drivers/gpu/drm/bridge/Makefile         |   1 +
 drivers/gpu/drm/bridge/lontium-lt8912.c | 749 ++++++++++++++++++++++++
 4 files changed, 765 insertions(+)
 create mode 100644 drivers/gpu/drm/bridge/lontium-lt8912.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 01e7e356bfac..65fb19382e40 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10476,6 +10476,7 @@ LONTIUM LT8912 MIPI TO HDMI BRIDGE
 M:	Adrien Grassein <adrien.grassein@gmail.com>
 S:	Maintained
 F:	Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
+F:	drivers/gpu/drm/bridge/lontium-lt8912.c
 
 LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
 M:	Sathya Prakash <sathya.prakash@broadcom.com>
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index e4110d6ca7b3..5b36d4b86e3c 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -48,6 +48,20 @@ config DRM_DISPLAY_CONNECTOR
 	  on ARM-based platforms. Saying Y here when this driver is not needed
 	  will not cause any issue.
 
+config DRM_LONTIUM_LT8912
+	tristate "Lontium LT8912 DSI/HDMI bridge"
+	depends on OF
+	select DRM_PANEL_BRIDGE
+	select DRM_KMS_HELPER
+	select REGMAP_I2C
+	help
+	  Driver for Lontium LT8912 DSI to HDMI bridge
+	  chip driver.
+	  Please say Y if you have such hardware.
+
+	  Say M here if you want to support this hardware as a module.
+	  The module will be named "lontium-lt8912".
+
 config DRM_LONTIUM_LT9611
 	tristate "Lontium LT9611 DSI/HDMI bridge"
 	select SND_SOC_HDMI_CODEC if SND_SOC
diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
index 86e7acc76f8d..5a1b201cea1f 100644
--- a/drivers/gpu/drm/bridge/Makefile
+++ b/drivers/gpu/drm/bridge/Makefile
@@ -2,6 +2,7 @@
 obj-$(CONFIG_DRM_CDNS_DSI) += cdns-dsi.o
 obj-$(CONFIG_DRM_CHRONTEL_CH7033) += chrontel-ch7033.o
 obj-$(CONFIG_DRM_DISPLAY_CONNECTOR) += display-connector.o
+obj-$(CONFIG_DRM_LONTIUM_LT8912) += lontium-lt8912.o
 obj-$(CONFIG_DRM_LONTIUM_LT9611) += lontium-lt9611.o
 obj-$(CONFIG_DRM_LONTIUM_LT9611UXC) += lontium-lt9611uxc.o
 obj-$(CONFIG_DRM_LVDS_CODEC) += lvds-codec.o
diff --git a/drivers/gpu/drm/bridge/lontium-lt8912.c b/drivers/gpu/drm/bridge/lontium-lt8912.c
new file mode 100644
index 000000000000..dd2ac92a5730
--- /dev/null
+++ b/drivers/gpu/drm/bridge/lontium-lt8912.c
@@ -0,0 +1,749 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
+#include <linux/regmap.h>
+
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_of.h>
+
+#include <video/videomode.h>
+
+#define I2C_MAIN 0
+#define I2C_ADDR_MAIN 0x48
+
+#define I2C_CEC_DSI 1
+#define I2C_ADDR_CEC_DSI 0x49
+
+#define I2C_MAX_IDX 2
+
+#define HPD_WORK_DELAY_MS 1000
+
+struct lt8912 {
+	struct device *dev;
+	struct drm_bridge bridge;
+	struct drm_connector connector;
+
+	struct i2c_adapter *ddc;
+	struct i2c_client *i2c_client[I2C_MAX_IDX];
+	struct regmap *regmap[I2C_MAX_IDX];
+
+	struct device_node *host_node;
+	struct mipi_dsi_device *dsi;
+
+	struct gpio_desc *gp_reset;
+
+	struct videomode mode;
+
+	u8 dsi_lanes;
+	bool is_power_on;
+	bool is_attached;
+	bool cable_is_attached;
+
+	struct workqueue_struct *workq;
+	struct delayed_work lt8912_check_hpd_work_id;
+};
+
+static int lt8912_write_init_config(struct lt8912 *lt)
+{
+	const struct reg_sequence seq[] = {
+		/* Digital clock en*/
+		{0x08, 0xff},
+		{0x09, 0xff},
+		{0x0a, 0xff},
+		{0x0b, 0x7c},
+		{0x0c, 0xff},
+		{0x42, 0x04},
+
+		/*Tx Analog*/
+		{0x31, 0xb1},
+		{0x32, 0xb1},
+		{0x33, 0x0e},
+		{0x37, 0x00},
+		{0x38, 0x22},
+		{0x60, 0x82},
+
+		/*Cbus Analog*/
+		{0x39, 0x45},
+		{0x3a, 0x00},
+		{0x3b, 0x00},
+
+		/*HDMI Pll Analog*/
+		{0x44, 0x31},
+		{0x55, 0x44},
+		{0x57, 0x01},
+		{0x5a, 0x02},
+
+		/*MIPI Analog*/
+		{0x3e, 0xd6},
+		{0x3f, 0xd4},
+		{0x41, 0x3c},
+		{0xB2, 0x00},
+	};
+
+	return regmap_multi_reg_write(lt->regmap[I2C_MAIN], seq, ARRAY_SIZE(seq));
+}
+
+static int lt8912_write_mipi_basic_config(struct lt8912 *lt)
+{
+	const struct reg_sequence seq[] = {
+		{0x12, 0x04},
+		{0x14, 0x00},
+		{0x15, 0x00},
+		{0x1a, 0x03},
+		{0x1b, 0x03},
+	};
+
+	return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq));
+};
+
+static int lt8912_write_dds_config(struct lt8912 *lt)
+{
+	const struct reg_sequence seq[] = {
+		{0x4e, 0xff},
+		{0x4f, 0x56},
+		{0x50, 0x69},
+		{0x51, 0x80},
+		{0x1f, 0x5e},
+		{0x20, 0x01},
+		{0x21, 0x2c},
+		{0x22, 0x01},
+		{0x23, 0xfa},
+		{0x24, 0x00},
+		{0x25, 0xc8},
+		{0x26, 0x00},
+		{0x27, 0x5e},
+		{0x28, 0x01},
+		{0x29, 0x2c},
+		{0x2a, 0x01},
+		{0x2b, 0xfa},
+		{0x2c, 0x00},
+		{0x2d, 0xc8},
+		{0x2e, 0x00},
+		{0x42, 0x64},
+		{0x43, 0x00},
+		{0x44, 0x04},
+		{0x45, 0x00},
+		{0x46, 0x59},
+		{0x47, 0x00},
+		{0x48, 0xf2},
+		{0x49, 0x06},
+		{0x4a, 0x00},
+		{0x4b, 0x72},
+		{0x4c, 0x45},
+		{0x4d, 0x00},
+		{0x52, 0x08},
+		{0x53, 0x00},
+		{0x54, 0xb2},
+		{0x55, 0x00},
+		{0x56, 0xe4},
+		{0x57, 0x0d},
+		{0x58, 0x00},
+		{0x59, 0xe4},
+		{0x5a, 0x8a},
+		{0x5b, 0x00},
+		{0x5c, 0x34},
+		{0x1e, 0x4f},
+		{0x51, 0x00},
+	};
+
+	return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq));
+}
+
+static int lt8912_write_rxlogicres_config(struct lt8912 *lt)
+{
+	int ret;
+
+	ret = regmap_write(lt->regmap[I2C_MAIN], 0x03, 0x7f);
+	usleep_range(10000, 20000);
+	ret |= regmap_write(lt->regmap[I2C_MAIN], 0x03, 0xff);
+
+	return ret;
+};
+
+static int lt8912_write_lvds_config(struct lt8912 *lt)
+{
+	const struct reg_sequence seq[] = {
+		{0x44, 0x30},
+		{0x51, 0x05},
+		{0x50, 0x24},
+		{0x51, 0x2d},
+		{0x52, 0x04},
+		{0x69, 0x0e},
+		{0x69, 0x8e},
+		{0x6a, 0x00},
+		{0x6c, 0xb8},
+		{0x6b, 0x51},
+		{0x04, 0xfb},
+		{0x04, 0xff},
+		{0x7f, 0x00},
+		{0xa8, 0x13},
+		{0x02, 0xf7},
+		{0x02, 0xff},
+		{0x03, 0xcf},
+		{0x03, 0xff},
+	};
+
+	return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq));
+};
+
+static inline struct lt8912 *bridge_to_lt8912(struct drm_bridge *b)
+{
+	return container_of(b, struct lt8912, bridge);
+}
+
+static inline struct lt8912 *connector_to_lt8912(struct drm_connector *c)
+{
+	return container_of(c, struct lt8912, connector);
+}
+
+static const struct regmap_config lt8912_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0xff,
+};
+
+static int lt8912_init_i2c(struct lt8912 *lt)
+{
+	unsigned int i;
+	int ret;
+	struct i2c_board_info info[] = {
+		{ I2C_BOARD_INFO("lt8912p0", I2C_ADDR_MAIN), },
+		{ I2C_BOARD_INFO("lt8912p1", I2C_ADDR_CEC_DSI), },
+	};
+
+	if (!lt)
+		return -ENODEV;
+
+	for (i = 0; i < ARRAY_SIZE(info); i++) {
+		if (i > 0) {
+			lt->i2c_client[i] = i2c_new_dummy_device(lt->i2c_client[0]->adapter,
+										info[i].addr);
+			if (!lt->i2c_client[i])
+				return -ENODEV;
+		}
+		lt->regmap[i] = devm_regmap_init_i2c(lt->i2c_client[i],
+							&lt8912_regmap_config);
+		if (IS_ERR(lt->regmap[i])) {
+			ret = PTR_ERR(lt->regmap[i]);
+			return ret;
+		}
+	}
+	return 0;
+}
+
+static int lt8912_free_i2c(struct lt8912 *lt)
+{
+	unsigned int i;
+
+	for (i = 1; i < I2C_MAX_IDX; i++)
+		i2c_unregister_device(lt->i2c_client[i]);
+
+	return 0;
+}
+
+static int lt8912_hard_power_on(struct lt8912 *lt)
+{
+	gpiod_set_value_cansleep(lt->gp_reset, 0);
+	msleep(20);
+
+	return 0;
+}
+
+static void lt8912_hard_power_off(struct lt8912 *lt)
+{
+	gpiod_set_value_cansleep(lt->gp_reset, 1);
+	msleep(20);
+	lt->is_power_on = false;
+}
+
+static int lt8912_video_setup(struct lt8912 *lt)
+{
+	u32 hactive, h_total, hpw, hfp, hbp;
+	u32 vactive, v_total, vpw, vfp, vbp;
+	u8 settle = 0x08;
+	int ret;
+
+	if (!lt)
+		return -EINVAL;
+
+	hactive = lt->mode.hactive;
+	hfp = lt->mode.hfront_porch;
+	hpw = lt->mode.hsync_len;
+	hbp = lt->mode.hback_porch;
+	h_total = hactive + hfp + hpw + hbp;
+
+	vactive = lt->mode.vactive;
+	vfp = lt->mode.vfront_porch;
+	vpw = lt->mode.vsync_len;
+	vbp = lt->mode.vback_porch;
+	v_total = vactive + vfp + vpw + vbp;
+
+	if (vactive <= 600)
+		settle = 0x04;
+	else if (vactive == 1080)
+		settle = 0x0a;
+
+	ret = regmap_write(lt->regmap[I2C_CEC_DSI], 0x10, 0x01);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x11, settle);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x18, hpw);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x19, vpw);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x1c, hactive & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x1d, hactive >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x2f, 0x0c);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x34, h_total & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x35, h_total >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x36, v_total & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x37, v_total >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x38, vbp & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x39, vbp >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3a, vfp & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3b, vfp >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3c, hbp & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3d, hbp >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3e, hfp & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3f, hfp >> 8);
+
+	return ret;
+}
+
+static int lt8912_soft_power_on(struct lt8912 *lt)
+{
+	if (!lt->is_power_on) {
+		u32 lanes = lt->dsi_lanes;
+
+		lt8912_write_init_config(lt);
+		regmap_write(lt->regmap[I2C_CEC_DSI], 0x13, lanes & 3);
+
+		lt8912_write_mipi_basic_config(lt);
+
+		queue_delayed_work(lt->workq,
+						   &lt->lt8912_check_hpd_work_id,
+						   msecs_to_jiffies(HPD_WORK_DELAY_MS));
+
+		lt->is_power_on = true;
+	}
+
+	return 0;
+}
+
+static int lt8912_video_on(struct lt8912 *lt)
+{
+	int ret;
+
+	ret = lt8912_video_setup(lt);
+	if (ret < 0)
+		goto end;
+
+	ret = lt8912_write_dds_config(lt);
+	if (ret < 0)
+		goto end;
+
+	ret = lt8912_write_rxlogicres_config(lt);
+	if (ret < 0)
+		goto end;
+
+	ret = lt8912_write_lvds_config(lt);
+	if (ret < 0)
+		goto end;
+
+end:
+	return ret;
+}
+
+static bool lt8912_cable_is_connected(struct lt8912 *lt)
+{
+	int ret;
+	unsigned int reg_val;
+
+	ret = regmap_read(lt->regmap[I2C_MAIN], 0xC1, &reg_val);
+	if (ret)
+		return 0;
+
+	return (reg_val & BIT(7));
+}
+
+static enum drm_connector_status
+lt8912_connector_detect(struct drm_connector *connector, bool force)
+{
+	struct lt8912 *lt = connector_to_lt8912(connector);
+
+	if (lt8912_cable_is_connected(lt))
+		return connector_status_connected;
+	else
+		return connector_status_disconnected;
+}
+
+static const struct drm_connector_funcs lt8912_connector_funcs = {
+	.detect = lt8912_connector_detect,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.destroy = drm_connector_cleanup,
+	.reset = drm_atomic_helper_connector_reset,
+	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static void lt8912_bridge_mode_set(struct drm_bridge *bridge,
+				   const struct drm_display_mode *mode,
+				   const struct drm_display_mode *adj)
+{
+	struct lt8912 *lt = bridge_to_lt8912(bridge);
+
+	drm_display_mode_to_videomode(adj, &lt->mode);
+}
+
+static enum drm_mode_status
+lt8912_connector_mode_valid(struct drm_connector *connector,
+			    struct drm_display_mode *mode)
+{
+	if (mode->clock > 150000)
+		return MODE_CLOCK_HIGH;
+
+	if (mode->hdisplay > 1920)
+		return MODE_BAD_HVALUE;
+
+	if (mode->vdisplay > 1080)
+		return MODE_BAD_VVALUE;
+
+	return MODE_OK;
+}
+
+static int lt8912_connector_get_modes(struct drm_connector *connector)
+{
+	struct edid *edid;
+	int ret, num = 0;
+	struct lt8912 *lt = connector_to_lt8912(connector);
+	u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+
+	edid = drm_get_edid(connector, lt->ddc);
+	if (edid) {
+		drm_connector_update_edid_property(connector, edid);
+		num = drm_add_edid_modes(connector, edid);
+	} else
+		return ret;
+
+	ret = drm_display_info_set_bus_formats(&connector->display_info,
+				&bus_format, 1);
+	if (ret)
+		return ret;
+
+	return num;
+}
+
+static const struct drm_connector_helper_funcs lt8912_connector_helper_funcs = {
+	.get_modes = lt8912_connector_get_modes,
+	.mode_valid = lt8912_connector_mode_valid,
+};
+
+static void lt8912_bridge_enable(struct drm_bridge *bridge)
+{
+	struct lt8912 *lt = bridge_to_lt8912(bridge);
+
+	lt8912_video_on(lt);
+}
+
+static void lt8912_check_hpd_work(struct work_struct *work)
+{
+	struct delayed_work *dw = to_delayed_work(work);
+	struct lt8912 *lt = container_of(dw, struct lt8912,
+			lt8912_check_hpd_work_id);
+	struct drm_connector *connector = &lt->connector;
+
+	bool current_state = lt8912_cable_is_connected(lt);
+
+	if (current_state != lt->cable_is_attached) {
+		drm_kms_helper_hotplug_event(connector->dev);
+		lt->cable_is_attached = current_state;
+	}
+
+	queue_delayed_work(lt->workq,
+					   &lt->lt8912_check_hpd_work_id,
+					  msecs_to_jiffies(HPD_WORK_DELAY_MS));
+}
+
+static int lt8912_attach_dsi(struct lt8912 *lt)
+{
+	struct device *dev = lt->dev;
+	struct mipi_dsi_host *host;
+	struct mipi_dsi_device *dsi;
+	int ret = -1;
+	const struct mipi_dsi_device_info info = { .type = "lt8912",
+						   .channel = 0,
+						   .node = NULL,
+						 };
+
+	host = of_find_mipi_dsi_host_by_node(lt->host_node);
+	if (!host) {
+		dev_err(dev, "failed to find dsi host\n");
+		return -EPROBE_DEFER;
+	}
+
+	dsi = mipi_dsi_device_register_full(host, &info);
+	if (IS_ERR(dsi)) {
+		ret = PTR_ERR(dsi);
+		dev_err(dev, "failed to create dsi device (%d)\n", ret);
+		goto err_dsi_device;
+	}
+
+	lt->dsi = dsi;
+
+	dsi->lanes = lt->dsi_lanes;
+	dsi->format = MIPI_DSI_FMT_RGB888;
+
+	dsi->mode_flags = MIPI_DSI_MODE_VIDEO |
+			MIPI_DSI_MODE_VIDEO_BURST |
+			MIPI_DSI_MODE_LPM |
+			MIPI_DSI_MODE_EOT_PACKET;
+
+	ret = mipi_dsi_attach(dsi);
+	if (ret < 0) {
+		dev_err(dev, "failed to attach dsi to host\n");
+		goto err_dsi_attach;
+	}
+
+	return 0;
+
+err_dsi_attach:
+	mipi_dsi_device_unregister(dsi);
+err_dsi_device:
+	return ret;
+}
+
+static void lt8912_detach_dsi(struct lt8912 *lt)
+{
+	mipi_dsi_detach(lt->dsi);
+	mipi_dsi_device_unregister(lt->dsi);
+}
+
+static int lt8912_bridge_init(struct drm_bridge *bridge)
+{
+	int ret;
+	struct lt8912 *lt = bridge_to_lt8912(bridge);
+	struct drm_connector *connector = &lt->connector;
+
+	lt->connector.polled = DRM_CONNECTOR_POLL_HPD;
+
+	ret = drm_connector_init(bridge->dev, connector,
+				 &lt8912_connector_funcs,
+				 DRM_MODE_CONNECTOR_HDMIA);
+	if (ret)
+		goto exit;
+
+	drm_connector_helper_add(connector, &lt8912_connector_helper_funcs);
+	connector->dpms = DRM_MODE_DPMS_OFF;
+	drm_connector_attach_encoder(connector, bridge->encoder);
+
+	ret = lt8912_hard_power_on(lt);
+	if (ret)
+		goto exit;
+
+	ret = lt8912_soft_power_on(lt);
+
+exit:
+	return ret;
+}
+
+static int lt8912_bridge_attach(struct drm_bridge *bridge,
+								enum drm_bridge_attach_flags flags)
+{
+	struct lt8912 *lt = bridge_to_lt8912(bridge);
+	int ret;
+
+	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
+		lt8912_bridge_init(bridge);
+
+	ret = lt8912_attach_dsi(lt);
+	if (ret)
+		return ret;
+
+	lt->is_attached = true;
+
+	return ret;
+}
+
+static void lt8912_bridge_detach(struct drm_bridge *bridge)
+{
+	struct lt8912 *lt = bridge_to_lt8912(bridge);
+
+	if (lt->is_attached) {
+		lt8912_detach_dsi(lt);
+		cancel_delayed_work_sync(&lt->lt8912_check_hpd_work_id);
+		lt8912_hard_power_off(lt);
+	}
+}
+
+static const struct drm_bridge_funcs lt8912_bridge_funcs = {
+	.attach = lt8912_bridge_attach,
+	.detach = lt8912_bridge_detach,
+	.mode_set = lt8912_bridge_mode_set,
+	.enable = lt8912_bridge_enable,
+};
+
+static int lt8912_parse_dt(struct lt8912 *lt)
+{
+	struct gpio_desc *gp_reset;
+	struct device_node *endpoint;
+	struct device *dev = lt->dev;
+	struct device_node *ddc;
+	u32 dsi_lanes;
+	int ret = 0;
+
+	gp_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(gp_reset)) {
+		ret = PTR_ERR(gp_reset);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Failed to get reset gpio: %d\n", ret);
+		return ret;
+	}
+	lt->gp_reset = gp_reset;
+
+	ret = of_property_read_u32(dev->of_node, "dsi-lanes", &dsi_lanes);
+	if (ret) {
+		dev_err(dev, "Failed to get dsi lanes count: %d\n", ret);
+		goto end;
+	}
+	lt->dsi_lanes = dsi_lanes;
+
+	ddc = of_parse_phandle(dev->of_node, "ddc-i2c-bus", 0);
+	if (ddc) {
+		lt->ddc = of_find_i2c_adapter_by_node(ddc);
+		of_node_put(ddc);
+		if (!lt->ddc) {
+			ret = -EPROBE_DEFER;
+			goto end;
+		}
+	} else
+		dev_err(lt->dev, "%s: no ddc-i2c-bus\n", __func__);
+
+	endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
+	if (!endpoint) {
+		dev_err(lt->dev, "%s: Failed to get endpoint\n", __func__);
+		ret = -ENODEV;
+		goto end;
+	}
+
+	lt->host_node = of_graph_get_remote_port_parent(endpoint);
+	if (!lt->host_node) {
+		dev_err(lt->dev, "%s: Failed to get remote port\n", __func__);
+		ret = -ENODEV;
+		goto error_remote_port;
+	}
+	of_node_put(endpoint);
+
+	return 0;
+
+error_remote_port:
+	of_node_put(endpoint);
+end:
+	return ret;
+}
+
+static int lt8912_put_dt(struct lt8912 *lt)
+{
+	of_node_put(lt->host_node);
+	return 0;
+}
+
+static int lt8912_probe(struct i2c_client *client,
+	 const struct i2c_device_id *id)
+{
+	static struct lt8912 *lt;
+	int ret = 0;
+	struct device *dev = &client->dev;
+
+	lt = devm_kzalloc(dev, sizeof(struct lt8912), GFP_KERNEL);
+	if (!lt)
+		return -ENOMEM;
+
+	lt->dev = dev;
+	lt->i2c_client[0] = client;
+
+	ret = lt8912_parse_dt(lt);
+	if (ret)
+		goto err_dt_parse;
+
+	ret = lt8912_init_i2c(lt);
+	if (ret)
+		goto err_i2c;
+
+	/* At this point of dev, my board has an issue with IRQ. So I decided to
+	 * replace to irq by a workqueue.
+	 */
+	lt->workq = create_workqueue("lt8912_workq");
+	if (!lt->workq) {
+		ret = -EPERM;
+		goto err_workqueue;
+	}
+
+	INIT_DELAYED_WORK(&lt->lt8912_check_hpd_work_id, lt8912_check_hpd_work);
+
+	i2c_set_clientdata(client, lt);
+
+	lt->bridge.funcs = &lt8912_bridge_funcs;
+	lt->bridge.of_node = dev->of_node;
+	drm_bridge_add(&lt->bridge);
+
+	return 0;
+
+err_workqueue:
+	lt8912_free_i2c(lt);
+err_i2c:
+	lt8912_put_dt(lt);
+err_dt_parse:
+	return ret;
+}
+
+static int lt8912_remove(struct i2c_client *client)
+{
+	struct lt8912 *lt = i2c_get_clientdata(client);
+
+	lt8912_bridge_detach(&lt->bridge);
+	drm_bridge_remove(&lt->bridge);
+	lt8912_free_i2c(lt);
+	lt8912_put_dt(lt);
+
+	return 0;
+}
+
+static const struct of_device_id lt8912_dt_match[] = {
+	{.compatible = "lontium,lt8912"},
+	{}
+};
+MODULE_DEVICE_TABLE(of, lt8912_dt_match);
+
+static const struct i2c_device_id lt8912_id[] = {
+	{"lt8912", 0},
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, lt8912_id);
+
+static struct i2c_driver lt8912_i2c_driver = {
+	.driver = {
+		.name = "lt8912",
+		.of_match_table = lt8912_dt_match,
+		.owner = THIS_MODULE,
+	},
+	.probe = lt8912_probe,
+	.remove = lt8912_remove,
+	.id_table = lt8912_id,
+};
+module_i2c_driver(lt8912_i2c_driver);
+
+MODULE_AUTHOR("Adrien Grassein <adrien.grassein@gmail.com>");
+MODULE_DESCRIPTION("lt8912 drm driver");
+MODULE_LICENSE("GPL v2");
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH 2/2] drm/bridge: Introduce LT8912 DSI to HDMI bridge
@ 2021-01-24 15:08   ` Adrien Grassein
  0 siblings, 0 replies; 10+ messages in thread
From: Adrien Grassein @ 2021-01-24 15:08 UTC (permalink / raw)
  Cc: devicetree, jernej.skrabec, narmstrong, airlied, jonas,
	linux-kernel, dri-devel, a.hajda, robh+dt, Laurent.pinchart,
	Adrien Grassein

Lontium Lt8912 is a DSI to HDMI bridge.

Signed-off-by: Adrien Grassein <adrien.grassein@gmail.com>
---
 MAINTAINERS                             |   1 +
 drivers/gpu/drm/bridge/Kconfig          |  14 +
 drivers/gpu/drm/bridge/Makefile         |   1 +
 drivers/gpu/drm/bridge/lontium-lt8912.c | 749 ++++++++++++++++++++++++
 4 files changed, 765 insertions(+)
 create mode 100644 drivers/gpu/drm/bridge/lontium-lt8912.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 01e7e356bfac..65fb19382e40 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10476,6 +10476,7 @@ LONTIUM LT8912 MIPI TO HDMI BRIDGE
 M:	Adrien Grassein <adrien.grassein@gmail.com>
 S:	Maintained
 F:	Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
+F:	drivers/gpu/drm/bridge/lontium-lt8912.c
 
 LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
 M:	Sathya Prakash <sathya.prakash@broadcom.com>
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index e4110d6ca7b3..5b36d4b86e3c 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -48,6 +48,20 @@ config DRM_DISPLAY_CONNECTOR
 	  on ARM-based platforms. Saying Y here when this driver is not needed
 	  will not cause any issue.
 
+config DRM_LONTIUM_LT8912
+	tristate "Lontium LT8912 DSI/HDMI bridge"
+	depends on OF
+	select DRM_PANEL_BRIDGE
+	select DRM_KMS_HELPER
+	select REGMAP_I2C
+	help
+	  Driver for Lontium LT8912 DSI to HDMI bridge
+	  chip driver.
+	  Please say Y if you have such hardware.
+
+	  Say M here if you want to support this hardware as a module.
+	  The module will be named "lontium-lt8912".
+
 config DRM_LONTIUM_LT9611
 	tristate "Lontium LT9611 DSI/HDMI bridge"
 	select SND_SOC_HDMI_CODEC if SND_SOC
diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
index 86e7acc76f8d..5a1b201cea1f 100644
--- a/drivers/gpu/drm/bridge/Makefile
+++ b/drivers/gpu/drm/bridge/Makefile
@@ -2,6 +2,7 @@
 obj-$(CONFIG_DRM_CDNS_DSI) += cdns-dsi.o
 obj-$(CONFIG_DRM_CHRONTEL_CH7033) += chrontel-ch7033.o
 obj-$(CONFIG_DRM_DISPLAY_CONNECTOR) += display-connector.o
+obj-$(CONFIG_DRM_LONTIUM_LT8912) += lontium-lt8912.o
 obj-$(CONFIG_DRM_LONTIUM_LT9611) += lontium-lt9611.o
 obj-$(CONFIG_DRM_LONTIUM_LT9611UXC) += lontium-lt9611uxc.o
 obj-$(CONFIG_DRM_LVDS_CODEC) += lvds-codec.o
diff --git a/drivers/gpu/drm/bridge/lontium-lt8912.c b/drivers/gpu/drm/bridge/lontium-lt8912.c
new file mode 100644
index 000000000000..dd2ac92a5730
--- /dev/null
+++ b/drivers/gpu/drm/bridge/lontium-lt8912.c
@@ -0,0 +1,749 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
+#include <linux/regmap.h>
+
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_of.h>
+
+#include <video/videomode.h>
+
+#define I2C_MAIN 0
+#define I2C_ADDR_MAIN 0x48
+
+#define I2C_CEC_DSI 1
+#define I2C_ADDR_CEC_DSI 0x49
+
+#define I2C_MAX_IDX 2
+
+#define HPD_WORK_DELAY_MS 1000
+
+struct lt8912 {
+	struct device *dev;
+	struct drm_bridge bridge;
+	struct drm_connector connector;
+
+	struct i2c_adapter *ddc;
+	struct i2c_client *i2c_client[I2C_MAX_IDX];
+	struct regmap *regmap[I2C_MAX_IDX];
+
+	struct device_node *host_node;
+	struct mipi_dsi_device *dsi;
+
+	struct gpio_desc *gp_reset;
+
+	struct videomode mode;
+
+	u8 dsi_lanes;
+	bool is_power_on;
+	bool is_attached;
+	bool cable_is_attached;
+
+	struct workqueue_struct *workq;
+	struct delayed_work lt8912_check_hpd_work_id;
+};
+
+static int lt8912_write_init_config(struct lt8912 *lt)
+{
+	const struct reg_sequence seq[] = {
+		/* Digital clock en*/
+		{0x08, 0xff},
+		{0x09, 0xff},
+		{0x0a, 0xff},
+		{0x0b, 0x7c},
+		{0x0c, 0xff},
+		{0x42, 0x04},
+
+		/*Tx Analog*/
+		{0x31, 0xb1},
+		{0x32, 0xb1},
+		{0x33, 0x0e},
+		{0x37, 0x00},
+		{0x38, 0x22},
+		{0x60, 0x82},
+
+		/*Cbus Analog*/
+		{0x39, 0x45},
+		{0x3a, 0x00},
+		{0x3b, 0x00},
+
+		/*HDMI Pll Analog*/
+		{0x44, 0x31},
+		{0x55, 0x44},
+		{0x57, 0x01},
+		{0x5a, 0x02},
+
+		/*MIPI Analog*/
+		{0x3e, 0xd6},
+		{0x3f, 0xd4},
+		{0x41, 0x3c},
+		{0xB2, 0x00},
+	};
+
+	return regmap_multi_reg_write(lt->regmap[I2C_MAIN], seq, ARRAY_SIZE(seq));
+}
+
+static int lt8912_write_mipi_basic_config(struct lt8912 *lt)
+{
+	const struct reg_sequence seq[] = {
+		{0x12, 0x04},
+		{0x14, 0x00},
+		{0x15, 0x00},
+		{0x1a, 0x03},
+		{0x1b, 0x03},
+	};
+
+	return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq));
+};
+
+static int lt8912_write_dds_config(struct lt8912 *lt)
+{
+	const struct reg_sequence seq[] = {
+		{0x4e, 0xff},
+		{0x4f, 0x56},
+		{0x50, 0x69},
+		{0x51, 0x80},
+		{0x1f, 0x5e},
+		{0x20, 0x01},
+		{0x21, 0x2c},
+		{0x22, 0x01},
+		{0x23, 0xfa},
+		{0x24, 0x00},
+		{0x25, 0xc8},
+		{0x26, 0x00},
+		{0x27, 0x5e},
+		{0x28, 0x01},
+		{0x29, 0x2c},
+		{0x2a, 0x01},
+		{0x2b, 0xfa},
+		{0x2c, 0x00},
+		{0x2d, 0xc8},
+		{0x2e, 0x00},
+		{0x42, 0x64},
+		{0x43, 0x00},
+		{0x44, 0x04},
+		{0x45, 0x00},
+		{0x46, 0x59},
+		{0x47, 0x00},
+		{0x48, 0xf2},
+		{0x49, 0x06},
+		{0x4a, 0x00},
+		{0x4b, 0x72},
+		{0x4c, 0x45},
+		{0x4d, 0x00},
+		{0x52, 0x08},
+		{0x53, 0x00},
+		{0x54, 0xb2},
+		{0x55, 0x00},
+		{0x56, 0xe4},
+		{0x57, 0x0d},
+		{0x58, 0x00},
+		{0x59, 0xe4},
+		{0x5a, 0x8a},
+		{0x5b, 0x00},
+		{0x5c, 0x34},
+		{0x1e, 0x4f},
+		{0x51, 0x00},
+	};
+
+	return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq));
+}
+
+static int lt8912_write_rxlogicres_config(struct lt8912 *lt)
+{
+	int ret;
+
+	ret = regmap_write(lt->regmap[I2C_MAIN], 0x03, 0x7f);
+	usleep_range(10000, 20000);
+	ret |= regmap_write(lt->regmap[I2C_MAIN], 0x03, 0xff);
+
+	return ret;
+};
+
+static int lt8912_write_lvds_config(struct lt8912 *lt)
+{
+	const struct reg_sequence seq[] = {
+		{0x44, 0x30},
+		{0x51, 0x05},
+		{0x50, 0x24},
+		{0x51, 0x2d},
+		{0x52, 0x04},
+		{0x69, 0x0e},
+		{0x69, 0x8e},
+		{0x6a, 0x00},
+		{0x6c, 0xb8},
+		{0x6b, 0x51},
+		{0x04, 0xfb},
+		{0x04, 0xff},
+		{0x7f, 0x00},
+		{0xa8, 0x13},
+		{0x02, 0xf7},
+		{0x02, 0xff},
+		{0x03, 0xcf},
+		{0x03, 0xff},
+	};
+
+	return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq));
+};
+
+static inline struct lt8912 *bridge_to_lt8912(struct drm_bridge *b)
+{
+	return container_of(b, struct lt8912, bridge);
+}
+
+static inline struct lt8912 *connector_to_lt8912(struct drm_connector *c)
+{
+	return container_of(c, struct lt8912, connector);
+}
+
+static const struct regmap_config lt8912_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0xff,
+};
+
+static int lt8912_init_i2c(struct lt8912 *lt)
+{
+	unsigned int i;
+	int ret;
+	struct i2c_board_info info[] = {
+		{ I2C_BOARD_INFO("lt8912p0", I2C_ADDR_MAIN), },
+		{ I2C_BOARD_INFO("lt8912p1", I2C_ADDR_CEC_DSI), },
+	};
+
+	if (!lt)
+		return -ENODEV;
+
+	for (i = 0; i < ARRAY_SIZE(info); i++) {
+		if (i > 0) {
+			lt->i2c_client[i] = i2c_new_dummy_device(lt->i2c_client[0]->adapter,
+										info[i].addr);
+			if (!lt->i2c_client[i])
+				return -ENODEV;
+		}
+		lt->regmap[i] = devm_regmap_init_i2c(lt->i2c_client[i],
+							&lt8912_regmap_config);
+		if (IS_ERR(lt->regmap[i])) {
+			ret = PTR_ERR(lt->regmap[i]);
+			return ret;
+		}
+	}
+	return 0;
+}
+
+static int lt8912_free_i2c(struct lt8912 *lt)
+{
+	unsigned int i;
+
+	for (i = 1; i < I2C_MAX_IDX; i++)
+		i2c_unregister_device(lt->i2c_client[i]);
+
+	return 0;
+}
+
+static int lt8912_hard_power_on(struct lt8912 *lt)
+{
+	gpiod_set_value_cansleep(lt->gp_reset, 0);
+	msleep(20);
+
+	return 0;
+}
+
+static void lt8912_hard_power_off(struct lt8912 *lt)
+{
+	gpiod_set_value_cansleep(lt->gp_reset, 1);
+	msleep(20);
+	lt->is_power_on = false;
+}
+
+static int lt8912_video_setup(struct lt8912 *lt)
+{
+	u32 hactive, h_total, hpw, hfp, hbp;
+	u32 vactive, v_total, vpw, vfp, vbp;
+	u8 settle = 0x08;
+	int ret;
+
+	if (!lt)
+		return -EINVAL;
+
+	hactive = lt->mode.hactive;
+	hfp = lt->mode.hfront_porch;
+	hpw = lt->mode.hsync_len;
+	hbp = lt->mode.hback_porch;
+	h_total = hactive + hfp + hpw + hbp;
+
+	vactive = lt->mode.vactive;
+	vfp = lt->mode.vfront_porch;
+	vpw = lt->mode.vsync_len;
+	vbp = lt->mode.vback_porch;
+	v_total = vactive + vfp + vpw + vbp;
+
+	if (vactive <= 600)
+		settle = 0x04;
+	else if (vactive == 1080)
+		settle = 0x0a;
+
+	ret = regmap_write(lt->regmap[I2C_CEC_DSI], 0x10, 0x01);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x11, settle);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x18, hpw);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x19, vpw);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x1c, hactive & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x1d, hactive >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x2f, 0x0c);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x34, h_total & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x35, h_total >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x36, v_total & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x37, v_total >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x38, vbp & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x39, vbp >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3a, vfp & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3b, vfp >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3c, hbp & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3d, hbp >> 8);
+
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3e, hfp & 0xff);
+	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3f, hfp >> 8);
+
+	return ret;
+}
+
+static int lt8912_soft_power_on(struct lt8912 *lt)
+{
+	if (!lt->is_power_on) {
+		u32 lanes = lt->dsi_lanes;
+
+		lt8912_write_init_config(lt);
+		regmap_write(lt->regmap[I2C_CEC_DSI], 0x13, lanes & 3);
+
+		lt8912_write_mipi_basic_config(lt);
+
+		queue_delayed_work(lt->workq,
+						   &lt->lt8912_check_hpd_work_id,
+						   msecs_to_jiffies(HPD_WORK_DELAY_MS));
+
+		lt->is_power_on = true;
+	}
+
+	return 0;
+}
+
+static int lt8912_video_on(struct lt8912 *lt)
+{
+	int ret;
+
+	ret = lt8912_video_setup(lt);
+	if (ret < 0)
+		goto end;
+
+	ret = lt8912_write_dds_config(lt);
+	if (ret < 0)
+		goto end;
+
+	ret = lt8912_write_rxlogicres_config(lt);
+	if (ret < 0)
+		goto end;
+
+	ret = lt8912_write_lvds_config(lt);
+	if (ret < 0)
+		goto end;
+
+end:
+	return ret;
+}
+
+static bool lt8912_cable_is_connected(struct lt8912 *lt)
+{
+	int ret;
+	unsigned int reg_val;
+
+	ret = regmap_read(lt->regmap[I2C_MAIN], 0xC1, &reg_val);
+	if (ret)
+		return 0;
+
+	return (reg_val & BIT(7));
+}
+
+static enum drm_connector_status
+lt8912_connector_detect(struct drm_connector *connector, bool force)
+{
+	struct lt8912 *lt = connector_to_lt8912(connector);
+
+	if (lt8912_cable_is_connected(lt))
+		return connector_status_connected;
+	else
+		return connector_status_disconnected;
+}
+
+static const struct drm_connector_funcs lt8912_connector_funcs = {
+	.detect = lt8912_connector_detect,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.destroy = drm_connector_cleanup,
+	.reset = drm_atomic_helper_connector_reset,
+	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static void lt8912_bridge_mode_set(struct drm_bridge *bridge,
+				   const struct drm_display_mode *mode,
+				   const struct drm_display_mode *adj)
+{
+	struct lt8912 *lt = bridge_to_lt8912(bridge);
+
+	drm_display_mode_to_videomode(adj, &lt->mode);
+}
+
+static enum drm_mode_status
+lt8912_connector_mode_valid(struct drm_connector *connector,
+			    struct drm_display_mode *mode)
+{
+	if (mode->clock > 150000)
+		return MODE_CLOCK_HIGH;
+
+	if (mode->hdisplay > 1920)
+		return MODE_BAD_HVALUE;
+
+	if (mode->vdisplay > 1080)
+		return MODE_BAD_VVALUE;
+
+	return MODE_OK;
+}
+
+static int lt8912_connector_get_modes(struct drm_connector *connector)
+{
+	struct edid *edid;
+	int ret, num = 0;
+	struct lt8912 *lt = connector_to_lt8912(connector);
+	u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+
+	edid = drm_get_edid(connector, lt->ddc);
+	if (edid) {
+		drm_connector_update_edid_property(connector, edid);
+		num = drm_add_edid_modes(connector, edid);
+	} else
+		return ret;
+
+	ret = drm_display_info_set_bus_formats(&connector->display_info,
+				&bus_format, 1);
+	if (ret)
+		return ret;
+
+	return num;
+}
+
+static const struct drm_connector_helper_funcs lt8912_connector_helper_funcs = {
+	.get_modes = lt8912_connector_get_modes,
+	.mode_valid = lt8912_connector_mode_valid,
+};
+
+static void lt8912_bridge_enable(struct drm_bridge *bridge)
+{
+	struct lt8912 *lt = bridge_to_lt8912(bridge);
+
+	lt8912_video_on(lt);
+}
+
+static void lt8912_check_hpd_work(struct work_struct *work)
+{
+	struct delayed_work *dw = to_delayed_work(work);
+	struct lt8912 *lt = container_of(dw, struct lt8912,
+			lt8912_check_hpd_work_id);
+	struct drm_connector *connector = &lt->connector;
+
+	bool current_state = lt8912_cable_is_connected(lt);
+
+	if (current_state != lt->cable_is_attached) {
+		drm_kms_helper_hotplug_event(connector->dev);
+		lt->cable_is_attached = current_state;
+	}
+
+	queue_delayed_work(lt->workq,
+					   &lt->lt8912_check_hpd_work_id,
+					  msecs_to_jiffies(HPD_WORK_DELAY_MS));
+}
+
+static int lt8912_attach_dsi(struct lt8912 *lt)
+{
+	struct device *dev = lt->dev;
+	struct mipi_dsi_host *host;
+	struct mipi_dsi_device *dsi;
+	int ret = -1;
+	const struct mipi_dsi_device_info info = { .type = "lt8912",
+						   .channel = 0,
+						   .node = NULL,
+						 };
+
+	host = of_find_mipi_dsi_host_by_node(lt->host_node);
+	if (!host) {
+		dev_err(dev, "failed to find dsi host\n");
+		return -EPROBE_DEFER;
+	}
+
+	dsi = mipi_dsi_device_register_full(host, &info);
+	if (IS_ERR(dsi)) {
+		ret = PTR_ERR(dsi);
+		dev_err(dev, "failed to create dsi device (%d)\n", ret);
+		goto err_dsi_device;
+	}
+
+	lt->dsi = dsi;
+
+	dsi->lanes = lt->dsi_lanes;
+	dsi->format = MIPI_DSI_FMT_RGB888;
+
+	dsi->mode_flags = MIPI_DSI_MODE_VIDEO |
+			MIPI_DSI_MODE_VIDEO_BURST |
+			MIPI_DSI_MODE_LPM |
+			MIPI_DSI_MODE_EOT_PACKET;
+
+	ret = mipi_dsi_attach(dsi);
+	if (ret < 0) {
+		dev_err(dev, "failed to attach dsi to host\n");
+		goto err_dsi_attach;
+	}
+
+	return 0;
+
+err_dsi_attach:
+	mipi_dsi_device_unregister(dsi);
+err_dsi_device:
+	return ret;
+}
+
+static void lt8912_detach_dsi(struct lt8912 *lt)
+{
+	mipi_dsi_detach(lt->dsi);
+	mipi_dsi_device_unregister(lt->dsi);
+}
+
+static int lt8912_bridge_init(struct drm_bridge *bridge)
+{
+	int ret;
+	struct lt8912 *lt = bridge_to_lt8912(bridge);
+	struct drm_connector *connector = &lt->connector;
+
+	lt->connector.polled = DRM_CONNECTOR_POLL_HPD;
+
+	ret = drm_connector_init(bridge->dev, connector,
+				 &lt8912_connector_funcs,
+				 DRM_MODE_CONNECTOR_HDMIA);
+	if (ret)
+		goto exit;
+
+	drm_connector_helper_add(connector, &lt8912_connector_helper_funcs);
+	connector->dpms = DRM_MODE_DPMS_OFF;
+	drm_connector_attach_encoder(connector, bridge->encoder);
+
+	ret = lt8912_hard_power_on(lt);
+	if (ret)
+		goto exit;
+
+	ret = lt8912_soft_power_on(lt);
+
+exit:
+	return ret;
+}
+
+static int lt8912_bridge_attach(struct drm_bridge *bridge,
+								enum drm_bridge_attach_flags flags)
+{
+	struct lt8912 *lt = bridge_to_lt8912(bridge);
+	int ret;
+
+	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
+		lt8912_bridge_init(bridge);
+
+	ret = lt8912_attach_dsi(lt);
+	if (ret)
+		return ret;
+
+	lt->is_attached = true;
+
+	return ret;
+}
+
+static void lt8912_bridge_detach(struct drm_bridge *bridge)
+{
+	struct lt8912 *lt = bridge_to_lt8912(bridge);
+
+	if (lt->is_attached) {
+		lt8912_detach_dsi(lt);
+		cancel_delayed_work_sync(&lt->lt8912_check_hpd_work_id);
+		lt8912_hard_power_off(lt);
+	}
+}
+
+static const struct drm_bridge_funcs lt8912_bridge_funcs = {
+	.attach = lt8912_bridge_attach,
+	.detach = lt8912_bridge_detach,
+	.mode_set = lt8912_bridge_mode_set,
+	.enable = lt8912_bridge_enable,
+};
+
+static int lt8912_parse_dt(struct lt8912 *lt)
+{
+	struct gpio_desc *gp_reset;
+	struct device_node *endpoint;
+	struct device *dev = lt->dev;
+	struct device_node *ddc;
+	u32 dsi_lanes;
+	int ret = 0;
+
+	gp_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(gp_reset)) {
+		ret = PTR_ERR(gp_reset);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Failed to get reset gpio: %d\n", ret);
+		return ret;
+	}
+	lt->gp_reset = gp_reset;
+
+	ret = of_property_read_u32(dev->of_node, "dsi-lanes", &dsi_lanes);
+	if (ret) {
+		dev_err(dev, "Failed to get dsi lanes count: %d\n", ret);
+		goto end;
+	}
+	lt->dsi_lanes = dsi_lanes;
+
+	ddc = of_parse_phandle(dev->of_node, "ddc-i2c-bus", 0);
+	if (ddc) {
+		lt->ddc = of_find_i2c_adapter_by_node(ddc);
+		of_node_put(ddc);
+		if (!lt->ddc) {
+			ret = -EPROBE_DEFER;
+			goto end;
+		}
+	} else
+		dev_err(lt->dev, "%s: no ddc-i2c-bus\n", __func__);
+
+	endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
+	if (!endpoint) {
+		dev_err(lt->dev, "%s: Failed to get endpoint\n", __func__);
+		ret = -ENODEV;
+		goto end;
+	}
+
+	lt->host_node = of_graph_get_remote_port_parent(endpoint);
+	if (!lt->host_node) {
+		dev_err(lt->dev, "%s: Failed to get remote port\n", __func__);
+		ret = -ENODEV;
+		goto error_remote_port;
+	}
+	of_node_put(endpoint);
+
+	return 0;
+
+error_remote_port:
+	of_node_put(endpoint);
+end:
+	return ret;
+}
+
+static int lt8912_put_dt(struct lt8912 *lt)
+{
+	of_node_put(lt->host_node);
+	return 0;
+}
+
+static int lt8912_probe(struct i2c_client *client,
+	 const struct i2c_device_id *id)
+{
+	static struct lt8912 *lt;
+	int ret = 0;
+	struct device *dev = &client->dev;
+
+	lt = devm_kzalloc(dev, sizeof(struct lt8912), GFP_KERNEL);
+	if (!lt)
+		return -ENOMEM;
+
+	lt->dev = dev;
+	lt->i2c_client[0] = client;
+
+	ret = lt8912_parse_dt(lt);
+	if (ret)
+		goto err_dt_parse;
+
+	ret = lt8912_init_i2c(lt);
+	if (ret)
+		goto err_i2c;
+
+	/* At this point of dev, my board has an issue with IRQ. So I decided to
+	 * replace to irq by a workqueue.
+	 */
+	lt->workq = create_workqueue("lt8912_workq");
+	if (!lt->workq) {
+		ret = -EPERM;
+		goto err_workqueue;
+	}
+
+	INIT_DELAYED_WORK(&lt->lt8912_check_hpd_work_id, lt8912_check_hpd_work);
+
+	i2c_set_clientdata(client, lt);
+
+	lt->bridge.funcs = &lt8912_bridge_funcs;
+	lt->bridge.of_node = dev->of_node;
+	drm_bridge_add(&lt->bridge);
+
+	return 0;
+
+err_workqueue:
+	lt8912_free_i2c(lt);
+err_i2c:
+	lt8912_put_dt(lt);
+err_dt_parse:
+	return ret;
+}
+
+static int lt8912_remove(struct i2c_client *client)
+{
+	struct lt8912 *lt = i2c_get_clientdata(client);
+
+	lt8912_bridge_detach(&lt->bridge);
+	drm_bridge_remove(&lt->bridge);
+	lt8912_free_i2c(lt);
+	lt8912_put_dt(lt);
+
+	return 0;
+}
+
+static const struct of_device_id lt8912_dt_match[] = {
+	{.compatible = "lontium,lt8912"},
+	{}
+};
+MODULE_DEVICE_TABLE(of, lt8912_dt_match);
+
+static const struct i2c_device_id lt8912_id[] = {
+	{"lt8912", 0},
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, lt8912_id);
+
+static struct i2c_driver lt8912_i2c_driver = {
+	.driver = {
+		.name = "lt8912",
+		.of_match_table = lt8912_dt_match,
+		.owner = THIS_MODULE,
+	},
+	.probe = lt8912_probe,
+	.remove = lt8912_remove,
+	.id_table = lt8912_id,
+};
+module_i2c_driver(lt8912_i2c_driver);
+
+MODULE_AUTHOR("Adrien Grassein <adrien.grassein@gmail.com>");
+MODULE_DESCRIPTION("lt8912 drm driver");
+MODULE_LICENSE("GPL v2");
-- 
2.25.1

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* Re: [PATCH 1/2] dt-bindings: display: bridge: Add documentation for LT8912
  2021-01-24 15:08   ` Adrien Grassein
@ 2021-02-09 16:38     ` Rob Herring
  -1 siblings, 0 replies; 10+ messages in thread
From: Rob Herring @ 2021-02-09 16:38 UTC (permalink / raw)
  To: Adrien Grassein
  Cc: airlied, daniel, a.hajda, narmstrong, Laurent.pinchart, jonas,
	jernej.skrabec, dri-devel, devicetree, linux-kernel

On Sun, Jan 24, 2021 at 04:08:34PM +0100, Adrien Grassein wrote:
> Lontium LT8912 is a DSI to HDMI bridge.
> 
> Signed-off-by: Adrien Grassein <adrien.grassein@gmail.com>
> ---
>  .../display/bridge/lontium,lt8912.yaml        | 92 +++++++++++++++++++
>  MAINTAINERS                                   |  5 +
>  2 files changed, 97 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
> new file mode 100644
> index 000000000000..ed1a6ddaab2f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
> @@ -0,0 +1,92 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/bridge/lontium,lt8912.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Lontium LT8912 MIPI to HDMI Bridge
> +
> +maintainers:
> +  - Adrien Grassein <adrien.grassein@gmail.com>
> +
> +description: |
> +  The LT8912 is a bridge device which convert DSI to HDMI
> +
> +properties:
> +  compatible:
> +    enum:
> +      - lontium,lt8912
> +
> +  reg:
> +    maxItems: 1
> +
> +  ddc-i2c-bus:

This belongs in an hdmi-connector node.

> +    maxItems: 1
> +    description: i2c bus used to read EDID of the connected display.
> +
> +  dsi-lanes:
> +    maxItems: 1
> +    description: dsi lanes count interconnected with lt8912.

'data-lanes' in the graph is the standard way to do this.

You'll need video-interfaces.yaml which is pending in the media tree.

> +
> +  reset-gpios:
> +    maxItems: 1
> +    description: GPIO connected to active high RESET pin.
> +
> +  ports:
> +    $ref: /schemas/graph.yaml#/properties/ports
> +
> +    properties:
> +      port@0:
> +        $ref: /schemas/graph.yaml#/properties/port
> +        description:
> +          Primary MIPI port-1 for MIPI input

You're going to need a port for the connector.

> +
> +    required:
> +      - port@0
> +
> +required:
> +  - compatible
> +  - ddc-i2c-bus
> +  - dsi-lanes
> +  - reg
> +  - reset-gpios
> +  - ports
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    i2c4 {
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +
> +      hdmi-bridge@48 {
> +        compatible = "lontium,lt8912";
> +        reg = <0x48>;
> +        reset-gpios = <&max7323 0 GPIO_ACTIVE_LOW>;
> +        dsi-lanes = <4>;
> +        ddc-i2c-bus = <&ddc_i2c_bus>;
> +
> +        ports {
> +          #address-cells = <1>;
> +          #size-cells = <0>;
> +
> +          port@0 {
> +            reg = <0>;
> +
> +            hdmi_out_in: endpoint {
> +              remote-endpoint = <&mipi_dsi_out>;
> +            };
> +          };
> +        };
> +      };
> +    };
> +
> +    ddc_i2c_bus: i2c5 {
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +    };
> +
> +...
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 5aa18cbfb883..01e7e356bfac 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -10472,6 +10472,11 @@ S:	Maintained
>  T:	git git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git
>  F:	drivers/hid/hid-lg-g15.c
>  
> +LONTIUM LT8912 MIPI TO HDMI BRIDGE
> +M:	Adrien Grassein <adrien.grassein@gmail.com>
> +S:	Maintained
> +F:	Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
> +
>  LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
>  M:	Sathya Prakash <sathya.prakash@broadcom.com>
>  M:	Sreekanth Reddy <sreekanth.reddy@broadcom.com>
> -- 
> 2.25.1
> 

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH 1/2] dt-bindings: display: bridge: Add documentation for LT8912
@ 2021-02-09 16:38     ` Rob Herring
  0 siblings, 0 replies; 10+ messages in thread
From: Rob Herring @ 2021-02-09 16:38 UTC (permalink / raw)
  To: Adrien Grassein
  Cc: devicetree, jernej.skrabec, jonas, airlied, narmstrong,
	linux-kernel, dri-devel, a.hajda, Laurent.pinchart

On Sun, Jan 24, 2021 at 04:08:34PM +0100, Adrien Grassein wrote:
> Lontium LT8912 is a DSI to HDMI bridge.
> 
> Signed-off-by: Adrien Grassein <adrien.grassein@gmail.com>
> ---
>  .../display/bridge/lontium,lt8912.yaml        | 92 +++++++++++++++++++
>  MAINTAINERS                                   |  5 +
>  2 files changed, 97 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
> new file mode 100644
> index 000000000000..ed1a6ddaab2f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
> @@ -0,0 +1,92 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/bridge/lontium,lt8912.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Lontium LT8912 MIPI to HDMI Bridge
> +
> +maintainers:
> +  - Adrien Grassein <adrien.grassein@gmail.com>
> +
> +description: |
> +  The LT8912 is a bridge device which convert DSI to HDMI
> +
> +properties:
> +  compatible:
> +    enum:
> +      - lontium,lt8912
> +
> +  reg:
> +    maxItems: 1
> +
> +  ddc-i2c-bus:

This belongs in an hdmi-connector node.

> +    maxItems: 1
> +    description: i2c bus used to read EDID of the connected display.
> +
> +  dsi-lanes:
> +    maxItems: 1
> +    description: dsi lanes count interconnected with lt8912.

'data-lanes' in the graph is the standard way to do this.

You'll need video-interfaces.yaml which is pending in the media tree.

> +
> +  reset-gpios:
> +    maxItems: 1
> +    description: GPIO connected to active high RESET pin.
> +
> +  ports:
> +    $ref: /schemas/graph.yaml#/properties/ports
> +
> +    properties:
> +      port@0:
> +        $ref: /schemas/graph.yaml#/properties/port
> +        description:
> +          Primary MIPI port-1 for MIPI input

You're going to need a port for the connector.

> +
> +    required:
> +      - port@0
> +
> +required:
> +  - compatible
> +  - ddc-i2c-bus
> +  - dsi-lanes
> +  - reg
> +  - reset-gpios
> +  - ports
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    i2c4 {
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +
> +      hdmi-bridge@48 {
> +        compatible = "lontium,lt8912";
> +        reg = <0x48>;
> +        reset-gpios = <&max7323 0 GPIO_ACTIVE_LOW>;
> +        dsi-lanes = <4>;
> +        ddc-i2c-bus = <&ddc_i2c_bus>;
> +
> +        ports {
> +          #address-cells = <1>;
> +          #size-cells = <0>;
> +
> +          port@0 {
> +            reg = <0>;
> +
> +            hdmi_out_in: endpoint {
> +              remote-endpoint = <&mipi_dsi_out>;
> +            };
> +          };
> +        };
> +      };
> +    };
> +
> +    ddc_i2c_bus: i2c5 {
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +    };
> +
> +...
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 5aa18cbfb883..01e7e356bfac 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -10472,6 +10472,11 @@ S:	Maintained
>  T:	git git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git
>  F:	drivers/hid/hid-lg-g15.c
>  
> +LONTIUM LT8912 MIPI TO HDMI BRIDGE
> +M:	Adrien Grassein <adrien.grassein@gmail.com>
> +S:	Maintained
> +F:	Documentation/devicetree/bindings/display/bridge/lontium,lt8912.yaml
> +
>  LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
>  M:	Sathya Prakash <sathya.prakash@broadcom.com>
>  M:	Sreekanth Reddy <sreekanth.reddy@broadcom.com>
> -- 
> 2.25.1
> 
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2021-02-09 16:39 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-01-24 15:08 [PATCH 0/2] Add support of Lontium lt8912 MIPI to HDMI bridge Adrien Grassein
2021-01-24 15:08 ` Adrien Grassein
2021-01-24 15:08 ` [PATCH 1/2] dt-bindings: display: bridge: Add documentation for LT8912 Adrien Grassein
2021-01-24 15:08   ` Adrien Grassein
2021-01-24 15:08 ` Adrien Grassein
2021-01-24 15:08   ` Adrien Grassein
2021-02-09 16:38   ` Rob Herring
2021-02-09 16:38     ` Rob Herring
2021-01-24 15:08 ` [PATCH 2/2] drm/bridge: Introduce LT8912 DSI to HDMI bridge Adrien Grassein
2021-01-24 15:08   ` Adrien Grassein

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