Add ilitek ili9341 panel driver

From: Dillon Min <[email protected]>

Since the st,sf-tc240t-9370-t dts binding already exist in stm32f429-disco.dts but, the panel driver didn't get accepted from mainline. it's time to submit patch fot it.

This driver can support two different interface by different dts bindings:
- spi+dpi, use spi to configure register, dpi for graphic data. st,sf-tc240t-9370-t
- only spi, just like tiny/ili9341.c (actually, this part is copy from tiny) adafruit,yx240qv29

I submited the first patch last year, you can find it at [1]. this patch has one major difference from that one, which is replace the low level communication way, from spi_sync() to mipi_dbi_{command, command_stackbuf}() interface, referred from Linus's patch [2].

both the two dpi/dbi interface was tested on stm32f429-disco board, if anyone want to verify this patch, you need apply the clk patch for this board first, you can get it from [3]

[1] "drm/panel: Add ilitek ili9341 panel driver"
https://lore.kernel.org/lkml/[email protected]/

[2] "drm/panel: s6e63m0: Switch to DBI abstraction for SPI"
https://lore.kernel.org/dri-devel/[email protected]/

[3]
https://lore.kernel.org/lkml/[email protected]/

v3:
- add Fixes tags.
- collect reviewed-by tags from linus and jagan.
- replace DRM_ERROR() with dev_err() or drm_err().
- remove kernel-doc markers from struct ili9341_config{}.
- reorder include headers.
- remove the struct device *dev from struct ili9341{}.
- restructure the ili9341_probe() function, add two ili9341_{dbi,dpi)_probe() to make it more readable according to jagan's suggestion, thanks.

for the full drm driver exist in drm/panel need Sam and Laurent's feedback. so, not cover this part at this time, will be update in v4.

v2 link:
https://lore.kernel.org/lkml/[email protected]/

v2:
- replace vcc regulator to bulk regulators in driver, from linus suggestion.
- fix dtbs_check warnings on ili9341 dts binding check.
- add bulk regulation node in ilitek,ili9341.yaml.
v1 link:
https://lore.kernel.org/lkml/[email protected]/

Dillon Min (3):
dt-bindings: display: panel: Add ilitek ili9341 panel bindings
ARM: dts: stm32: fix dtbs_check warning on ili9341 dts binding drm/panel: Add ilitek ili9341 panel driver

 .../bindings/display/panel/ilitek,ili9341.yaml     |  78 ++
 arch/arm/boot/dts/stm32f429-disco.dts              |   2 +-
 drivers/gpu/drm/panel/Kconfig                      |  12 +
 drivers/gpu/drm/panel/Makefile                     |   1 +
 drivers/gpu/drm/panel/panel-ilitek-ili9341.c       | 786 +++++++++++++++++++++
 5 files changed, 878 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/devicetree/bindings/display/panel/ilitek,ili9341.yaml
 create mode 100644 drivers/gpu/drm/panel/panel-ilitek-ili9341.c

2.7.4

From: Dillon Min <[email protected]>

Add documentation for "ilitek,ili9341" panel.

---
v3:
- collect reviewed-by tags from linus.
- add link address.

 .../bindings/display/panel/ilitek,ili9341.yaml     | 78 ++++++++++++++++++++++
 1 file changed, 78 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/ilitek,ili9341.yaml

new file mode 100644
index 000000000000..2ed010f91e2d
@@ -0,0 +1,78 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/ilitek,ili9341.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Ilitek-9341 Display Panel
+
+maintainers:
+  - Dillon Min <[email protected]>
+
+description: |
+  Ilitek ILI9341 TFT panel driver with SPI control bus
+  This is a driver for 320x240 TFT panels, accepting a rgb input
+  streams with 16 bits or 18 bits.
+
+allOf:
+  - $ref: panel-common.yaml#
+
+properties:
+  compatible:
+    items:
+      - enum:
+          # ili9341 240*320 Color on stm32f429-disco board
+        - st,sf-tc240t-9370-t
+      - const: ilitek,ili9341
+
+  reg: true
+
+  dc-gpios:
+    maxItems: 1
+    description: Display data/command selection (D/CX) of this DBI panel
+
+  spi-3wire: true
+
+  spi-max-frequency:
+    const: 10000000
+
+  port: true
+
+  vci-supply:
+    description: Analog voltage supply (2.5 .. 3.3V)
+
+  vddi-supply:
+    description: Voltage supply for interface logic (1.65 .. 3.3 V)
+
+  vddi-led-supply:
+    description: Voltage supply for the LED driver (1.65 .. 3.3 V)
+
+additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - dc-gpios
+  - port
+
+examples:
+  - |+
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+        panel: display@0 {
+                 compatible = "st,sf-tc240t-9370-t",
+                              "ilitek,ili9341";
+                 reg = <0>;
+                 spi-3wire;
+                 spi-max-frequency = <10000000>;
+                 dc-gpios = <&gpiod 13 0>;
+                 port {
+                         panel_in: endpoint {
+                           remote-endpoint = <&display_out>;
+                      };
+                 };
+             };
+        };
+...
+

2.7.4

From: Dillon Min <[email protected]>

Since the compatible string defined from ilitek,ili9341.yaml is "st,sf-tc240t-9370-t", "ilitek,ili9341"

so, append "ilitek,ili9341" to avoid the below dtbs_check warning.

arch/arm/boot/dts/stm32f429-disco.dt.yaml: display@1: compatible:
['st,sf-tc240t-9370-t'] is too short

---
v3:
- add Fixes tags.

 arch/arm/boot/dts/stm32f429-disco.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 075ac57d0bf4..6435e099c632 100644
@@ -192,7 +192,7 @@
 
 	display: display@1{
 		/* Connect panel-ilitek-9341 to ltdc */
-		compatible = "st,sf-tc240t-9370-t";
+		compatible = "st,sf-tc240t-9370-t", "ilitek,ili9341";
 		reg = <1>;
 		spi-3wire;
 		spi-max-frequency = <10000000>;

2.7.4

From: Dillon Min <[email protected]>

This driver combines tiny/ili9341.c mipi_dbi_interface driver with mipi_dpi_interface driver, and can support ili9341 with serial mode or parallel rgb interface mode by register configuration.

---
v3:
all the v3 updates are based on Sam and Jagan's review.
- collect reviewed-by tags from linus and jagan.
- replace DRM_ERROR() with dev_err() or drm_err().
- remove kernel-doc markers from struct ili9341_config{}.
- reorder include headers.
- remove the struct device *dev from struct ili9341{}.
- restructure the ili9341_probe() function, add two ili9341_{dbi,dpi)_probe() to make it more readable according to jagan's suggestion, thanks.

For "So this is a full display driver. The more relevant home for this driver is inside drm/tiny/."

I'm not sure if this is to ask me move the dpi code to drm/tiny/ili9341.c, and remove this driver. or just remove the dbi code from this driver, but this will result in two drivers to support the same panel (as Noralf does not agree with it).

so, waiting for the decision from Sam, Laurent, then will update in v4, thanks.

 drivers/gpu/drm/panel/Kconfig                |  12 +
 drivers/gpu/drm/panel/Makefile               |   1 +
 drivers/gpu/drm/panel/panel-ilitek-ili9341.c | 786 +++++++++++++++++++++++++++
 3 files changed, 799 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-ilitek-ili9341.c

index ef87d92cdf49..eb34b8d1b19a 100644
@@ -124,6 +124,18 @@ config DRM_PANEL_ILITEK_IL9322
 	  Say Y here if you want to enable support for Ilitek IL9322
 	  QVGA (320x240) RGB, YUV and ITU-T BT.656 panels.
 
+config DRM_PANEL_ILITEK_ILI9341
+	tristate "Ilitek ILI9341 240x320 QVGA panels"
+	depends on OF && SPI
+	depends on DRM_KMS_HELPER
+	depends on DRM_KMS_CMA_HELPER
+	depends on BACKLIGHT_CLASS_DEVICE
+	select DRM_MIPI_DBI
+	help
+	  Say Y here if you want to enable support for Ilitek IL9341
+	  QVGA (240x320) RGB panels. support serial & parallel rgb
+	  interface.
+
 config DRM_PANEL_ILITEK_ILI9881C
 	tristate "Ilitek ILI9881C-based panels"
 	depends on OF

index cae4d976c069..0ecde184665d 100644
@@ -11,6 +11,7 @@ obj-$(CONFIG_DRM_PANEL_ELIDA_KD35T133) += panel-elida-kd35t133.o
 obj-$(CONFIG_DRM_PANEL_FEIXIN_K101_IM2BA02) += panel-feixin-k101-im2ba02.o
 obj-$(CONFIG_DRM_PANEL_FEIYANG_FY07024DI26A30D) += panel-feiyang-fy07024di26a30d.o
 obj-$(CONFIG_DRM_PANEL_ILITEK_IL9322) += panel-ilitek-ili9322.o
+obj-$(CONFIG_DRM_PANEL_ILITEK_ILI9341) += panel-ilitek-ili9341.o
 obj-$(CONFIG_DRM_PANEL_ILITEK_ILI9881C) += panel-ilitek-ili9881c.o
 obj-$(CONFIG_DRM_PANEL_INNOLUX_P079ZCA) += panel-innolux-p079zca.o
 obj-$(CONFIG_DRM_PANEL_JDI_LT070ME05000) += panel-jdi-lt070me05000.o

2.7.4

Hi lkp,

Thanks for pointing that out,
I missed "{}" at the end of struct of_device_id ili9341_of_match[].

I'll fix it in v4, with your Reported-by tags.

Thanks
Best Regards

Dillon