[PATCH v2 0/2] Add support for the AUO A030JTN01 TFT LCD

[PATCH v2 0/2] Add support for the AUO A030JTN01 TFT LCD

[Christophe Branchereau]

Changes since v1:
 reworked the dt-bindings to add a spi node, dropped properties already 
 present in panel-common.yaml

Christophe Branchereau (1):
  drm/panel: Add driver for the AUO A030JTN01 TFT LCD

Paul Cercueil (1):
  dt-bindings: display/panel: Add AUO A030JTN01

 .../bindings/display/panel/auo,a030jtn01.yaml |  61 ++++
 drivers/gpu/drm/panel/Kconfig                 |   8 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 drivers/gpu/drm/panel/panel-auo-a030jtn01.c   | 295 ++++++++++++++++++
 4 files changed, 365 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/auo,a030jtn01.yaml
 create mode 100644 drivers/gpu/drm/panel/panel-auo-a030jtn01.c

-- 
2.35.1

[PATCH v2 1/2] drm/panel: Add driver for the AUO A030JTN01 TFT LCD

[Christophe Branchereau]

Add driver for the AUO A030JTN01 panel, which is a 320x480 3.0" 4:3
24-bit TFT LCD panel with non-square pixels and a delta-RGB 8-bit
interface.

Signed-off-by: Christophe Branchereau <cbranchereau@gmail.com>
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
---
 drivers/gpu/drm/panel/Kconfig               |   8 +
 drivers/gpu/drm/panel/Makefile              |   1 +
 drivers/gpu/drm/panel/panel-auo-a030jtn01.c | 295 ++++++++++++++++++++
 3 files changed, 304 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-auo-a030jtn01.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index a582ddd583c2..3db85c68d182 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -8,6 +8,14 @@ config DRM_PANEL
 menu "Display Panels"
 	depends on DRM && DRM_PANEL
 
+config DRM_PANEL_AUO_A030JTN01
+	tristate "AUO A030JTN01"
+	depends on OF && SPI
+	select REGMAP_SPI
+	help
+	  Say Y here to enable support for the AUO A030JTN01 320x480 3.0" panel
+	  as found in the YLM RS-97 handheld gaming console.
+
 config DRM_PANEL_ABT_Y030XX067A
 	tristate "ABT Y030XX067A 320x480 LCD panel"
 	depends on OF && SPI
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index 34e717382dbb..f425599c2717 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_DRM_PANEL_AUO_A030JTN01) += panel-auo-a030jtn01.o
 obj-$(CONFIG_DRM_PANEL_ABT_Y030XX067A) += panel-abt-y030xx067a.o
 obj-$(CONFIG_DRM_PANEL_ARM_VERSATILE) += panel-arm-versatile.o
 obj-$(CONFIG_DRM_PANEL_ASUS_Z00T_TM5P5_NT35596) += panel-asus-z00t-tm5p5-n35596.o
diff --git a/drivers/gpu/drm/panel/panel-auo-a030jtn01.c b/drivers/gpu/drm/panel/panel-auo-a030jtn01.c
new file mode 100644
index 000000000000..1c4f812e9483
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-auo-a030jtn01.c
@@ -0,0 +1,295 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AU Optronics A030JTN01.0 TFT LCD panel driver
+ *
+ * Copyright (C) 2020, Paul Cercueil <paul@crapouillou.net>
+ * Copyright (C) 2020, Christophe Branchereau <cbranchereau@gmail.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/media-bus-format.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+
+struct a030jtn01_info {
+	const struct drm_display_mode *display_modes;
+	unsigned int num_modes;
+	u16 width_mm, height_mm;
+	u32 bus_format, bus_flags;
+};
+
+struct a030jtn01 {
+	struct drm_panel panel;
+	struct spi_device *spi;
+	struct regmap *map;
+
+	const struct a030jtn01_info *panel_info;
+
+	struct regulator *supply;
+	struct gpio_desc *reset_gpio;
+};
+
+static inline struct a030jtn01 *to_a030jtn01(struct drm_panel *panel)
+{
+	return container_of(panel, struct a030jtn01, panel);
+}
+
+static int a030jtn01_prepare(struct drm_panel *panel)
+{
+	struct a030jtn01 *priv = to_a030jtn01(panel);
+	struct device *dev = &priv->spi->dev;
+	int err;
+
+	err = regulator_enable(priv->supply);
+	if (err) {
+		dev_err(dev, "Failed to enable power supply: %d\n", err);
+		return err;
+	}
+
+	usleep_range(1000, 8000);
+
+	/* Reset the chip */
+	gpiod_set_value_cansleep(priv->reset_gpio, 1);
+	usleep_range(100, 8000);
+	gpiod_set_value_cansleep(priv->reset_gpio, 0);
+	usleep_range(2000, 8000);
+
+	/*
+	 * No idea why two writes are needed. If this write is commented,
+	 * the colors are wrong. Doesn't seem to be timing-related, since
+	 * a msleep(200) doesn't fix it.
+	 */
+	regmap_write(priv->map, 0x06, 0x00);
+
+	/* Use (24 + 6) == 0x1e as the vertical back porch */
+	err = regmap_write(priv->map, 0x06, 0x1e);
+	if (err)
+		goto err_disable_regulator;
+
+	/* Use (42 + 30) * 3 == 0xd8 as the horizontal back porch */
+	err = regmap_write(priv->map, 0x07, 0xd8);
+	if (err)
+		goto err_disable_regulator;
+
+	regmap_write(priv->map, 0x05, 0x74);
+
+	return 0;
+
+err_disable_regulator:
+	gpiod_set_value_cansleep(priv->reset_gpio, 1);
+	regulator_disable(priv->supply);
+	return err;
+}
+
+static int a030jtn01_unprepare(struct drm_panel *panel)
+{
+	struct a030jtn01 *priv = to_a030jtn01(panel);
+
+	gpiod_set_value_cansleep(priv->reset_gpio, 1);
+	regulator_disable(priv->supply);
+
+	return 0;
+}
+
+static int a030jtn01_enable(struct drm_panel *panel)
+{
+	struct a030jtn01 *priv = to_a030jtn01(panel);
+	int ret;
+
+	ret = regmap_write(priv->map, 0x05, 0x75);
+	if (ret)
+		return ret;
+
+	/* Wait for the picture to be stable */
+	if (panel->backlight)
+		msleep(100);
+
+	return 0;
+}
+
+static int a030jtn01_disable(struct drm_panel *panel)
+{
+	struct a030jtn01 *priv = to_a030jtn01(panel);
+
+	return regmap_write(priv->map, 0x05, 0x74);
+}
+
+static int a030jtn01_get_modes(struct drm_panel *panel,
+				struct drm_connector *connector)
+{
+	struct a030jtn01 *priv = to_a030jtn01(panel);
+	const struct a030jtn01_info *panel_info = priv->panel_info;
+	struct drm_display_mode *mode;
+	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);
+
+		mode->type = DRM_MODE_TYPE_DRIVER;
+		if (panel_info->num_modes == 1)
+			mode->type |= DRM_MODE_TYPE_PREFERRED;
+
+		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;
+
+	drm_display_info_set_bus_formats(&connector->display_info,
+					 &panel_info->bus_format, 1);
+	connector->display_info.bus_flags = panel_info->bus_flags;
+
+	return panel_info->num_modes;
+}
+
+static const struct drm_panel_funcs a030jtn01_funcs = {
+	.prepare	= a030jtn01_prepare,
+	.unprepare	= a030jtn01_unprepare,
+	.enable		= a030jtn01_enable,
+	.disable	= a030jtn01_disable,
+	.get_modes	= a030jtn01_get_modes,
+};
+
+static bool a030jtn01_has_reg(struct device *dev, unsigned int reg)
+{
+	static const u32 a030jtn01_regs_mask = 0x001823f1fb;
+
+	return a030jtn01_regs_mask & BIT(reg);
+};
+
+static const struct regmap_config a030jtn01_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.read_flag_mask = 0x40,
+	.max_register = 0x1c,
+	.readable_reg = a030jtn01_has_reg,
+	.writeable_reg = a030jtn01_has_reg,
+};
+
+static int a030jtn01_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct a030jtn01 *priv;
+	int err;
+
+	spi->mode |= SPI_MODE_3 | SPI_3WIRE;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->spi = spi;
+	spi_set_drvdata(spi, priv);
+
+	priv->map = devm_regmap_init_spi(spi, &a030jtn01_regmap_config);
+	if (IS_ERR(priv->map)) {
+		dev_err(dev, "Unable to init regmap\n");
+		return PTR_ERR(priv->map);
+	}
+
+	priv->panel_info = of_device_get_match_data(dev);
+	if (!priv->panel_info)
+		return -EINVAL;
+
+	priv->supply = devm_regulator_get(dev, "power");
+	if (IS_ERR(priv->supply)) {
+		dev_err(dev, "Failed to get power supply\n");
+		return PTR_ERR(priv->supply);
+	}
+
+	priv->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(priv->reset_gpio)) {
+		dev_err(dev, "Failed to get reset GPIO\n");
+		return PTR_ERR(priv->reset_gpio);
+	}
+
+	drm_panel_init(&priv->panel, dev, &a030jtn01_funcs,
+		       DRM_MODE_CONNECTOR_DPI);
+
+	err = drm_panel_of_backlight(&priv->panel);
+	if (err)
+		return err;
+
+	drm_panel_add(&priv->panel);
+
+	return 0;
+}
+
+static void a030jtn01_remove(struct spi_device *spi)
+{
+	struct a030jtn01 *priv = spi_get_drvdata(spi);
+
+	drm_panel_remove(&priv->panel);
+	drm_panel_disable(&priv->panel);
+	drm_panel_unprepare(&priv->panel);
+}
+
+static const struct drm_display_mode a030jtn01_modes[] = {
+	{ /* 60 Hz */
+		.clock = 14400,
+		.hdisplay = 320,
+		.hsync_start = 320 + 8,
+		.hsync_end = 320 + 8 + 42,
+		.htotal = 320 + 8 + 42 + 30,
+		.vdisplay = 480,
+		.vsync_start = 480 + 90,
+		.vsync_end = 480 + 90 + 24,
+		.vtotal = 480 + 90 + 24 + 6,
+		.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
+	},
+	{ /* 50 Hz */
+		.clock = 12000,
+		.hdisplay = 320,
+		.hsync_start = 320 + 8,
+		.hsync_end = 320 + 8 + 42,
+		.htotal = 320 + 8 + 42 + 30,
+		.vdisplay = 480,
+		.vsync_start = 480 + 90,
+		.vsync_end = 480 + 90 + 24,
+		.vtotal = 480 + 90 + 24 + 6,
+		.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
+	},
+};
+
+static const struct a030jtn01_info a030jtn01_info = {
+	.display_modes = a030jtn01_modes,
+	.num_modes = ARRAY_SIZE(a030jtn01_modes),
+	.width_mm = 70,
+	.height_mm = 51,
+	.bus_format = MEDIA_BUS_FMT_RGB888_3X8_DELTA,
+	.bus_flags = DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE,
+};
+
+static const struct of_device_id a030jtn01_of_match[] = {
+	{ .compatible = "auo,a030jtn01", .data = &a030jtn01_info },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, a030jtn01_of_match);
+
+static struct spi_driver a030jtn01_driver = {
+	.driver = {
+		.name = "auo-a030jtn01",
+		.of_match_table = a030jtn01_of_match,
+	},
+	.probe = a030jtn01_probe,
+	.remove = a030jtn01_remove,
+};
+module_spi_driver(a030jtn01_driver);
+
+MODULE_AUTHOR("Paul Cercueil <paul@crapouillou.net>");
+MODULE_AUTHOR("Christophe Branchereau <cbranchereau@gmail.com>");
+MODULE_LICENSE("GPL v2");
-- 
2.35.1

[PATCH v2 2/2] dt-bindings: display/panel: Add AUO A030JTN01

[Christophe Branchereau]

From: Paul Cercueil <paul@crapouillou.net>

Add binding for the AUO A030JTN01 panel, which is a 320x480 3.0" 4:3
24-bit TFT LCD panel with non-square pixels and a delta-RGB 8-bit
interface.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Christophe Branchereau <cbranchereau@gmail.com>
---
 .../bindings/display/panel/auo,a030jtn01.yaml | 61 +++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/auo,a030jtn01.yaml

diff --git a/Documentation/devicetree/bindings/display/panel/auo,a030jtn01.yaml b/Documentation/devicetree/bindings/display/panel/auo,a030jtn01.yaml
new file mode 100644
index 000000000000..6c099eb63434
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/panel/auo,a030jtn01.yaml
@@ -0,0 +1,61 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/auo,a030jtn01.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: AUO A030JTN01 3.0" (320x480 pixels) 24-bit TFT LCD panel
+
+description: |
+  The panel must obey the rules for a SPI slave device as specified in
+  spi/spi-controller.yaml
+
+maintainers:
+  - Paul Cercueil <paul@crapouillou.net>
+  - Christophe Branchereau <cbranchereau@gmail.com>
+
+allOf:
+  - $ref: panel-common.yaml#
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+  compatible:
+    const: auo,a030jtn01
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - power-supply
+  - reset-gpios
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        panel@0 {
+            compatible = "auo,a030jtn01";
+            reg = <0>;
+
+            spi-max-frequency = <10000000>;
+
+            reset-gpios = <&gpe 4 GPIO_ACTIVE_LOW>;
+            power-supply = <&lcd_power>;
+
+            backlight = <&backlight>;
+
+            port {
+                panel_input: endpoint {
+                    remote-endpoint = <&panel_output>;
+                };
+            };
+        };
+    };
-- 
2.35.1

Re: [PATCH v2 2/2] dt-bindings: display/panel: Add AUO A030JTN01

[Krzysztof Kozlowski]

On 14/12/2022 12:41, Christophe Branchereau wrote:
> From: Paul Cercueil <paul@crapouillou.net>
> 
> Add binding for the AUO A030JTN01 panel, which is a 320x480 3.0" 4:3
> 24-bit TFT LCD panel with non-square pixels and a delta-RGB 8-bit
> interface.
> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> Signed-off-by: Christophe Branchereau <cbranchereau@gmail.com>
> ---
>  .../bindings/display/panel/auo,a030jtn01.yaml | 61 +++++++++++++++++++
>  1 file changed, 61 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/panel/auo,a030jtn01.yaml
> 
> diff --git a/Documentation/devicetree/bindings/display/panel/auo,a030jtn01.yaml b/Documentation/devicetree/bindings/display/panel/auo,a030jtn01.yaml
> new file mode 100644
> index 000000000000..6c099eb63434
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/panel/auo,a030jtn01.yaml
> @@ -0,0 +1,61 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/panel/auo,a030jtn01.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: AUO A030JTN01 3.0" (320x480 pixels) 24-bit TFT LCD panel
> +
> +description: |
> +  The panel must obey the rules for a SPI slave device as specified in
> +  spi/spi-controller.yaml

Drop such description - it's obvious from referencing the schema below.
No need to open-write it in each binding. OTOH, you could describe here
the hardware more.

With adjusted description:

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof