drm/panel: jh057n0090: Add regulators and drop magic value in init

0xBF isn't in any ST7703 data sheet so mark it as unknown. This avoids confusion on whether there is a missing command in that dsi_generic_write_seq() call.

Signed-off-by Guido Günther <[email protected]>

---
 drivers/gpu/drm/panel/panel-rocktech-jh057n00900.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

drivers/gpu/drm/panel/panel-rocktech-jh057n00900.c +2 -1

index 6dcb692c4701..b8a069055fbc 100644
@@ -33,6 +33,7 @@
 #define ST7703_CMD_SETEXTC	 0xB9
 #define ST7703_CMD_SETMIPI	 0xBA
 #define ST7703_CMD_SETVDC	 0xBC
+#define ST7703_CMD_UNKNOWN0	 0xBF
 #define ST7703_CMD_SETSCR	 0xC0
 #define ST7703_CMD_SETPOWER	 0xC1
 #define ST7703_CMD_SETPANEL	 0xCC

@@ -94,7 +95,7 @@ static int jh057n_init_sequence(struct jh057n *ctx)
 	msleep(20);
 
 	dsi_generic_write_seq(dsi, ST7703_CMD_SETVCOM, 0x3F, 0x3F);
-	dsi_generic_write_seq(dsi, 0xBF, 0x02, 0x11, 0x00);
+	dsi_generic_write_seq(dsi, ST7703_CMD_UNKNOWN0, 0x02, 0x11, 0x00);
 	dsi_generic_write_seq(dsi, ST7703_CMD_SETGIP1,
 			      0x82, 0x10, 0x06, 0x05, 0x9E, 0x0A, 0xA5, 0x12,
 			      0x31, 0x23, 0x37, 0x83, 0x04, 0xBC, 0x27, 0x38,

Signature · 1 line

2.20.1

Document the vcc-supply and iovcc-supply propertes of the Rocktech jh057n0090 panel.

Signed-off-by Guido Günther <[email protected]>

---
 .../bindings/display/panel/rocktech,jh057n00900.txt          | 5 +++++
 1 file changed, 5 insertions(+)

Documentation/devicetree/bindings/display/panel/rocktech,jh057n00900.txt +5 -0

index 1b5763200cf6..a372c5d84695 100644
@@ -5,6 +5,9 @@ Required properties:
 - reg: DSI virtual channel of the peripheral
 - reset-gpios: panel reset gpio
 - backlight: phandle of the backlight device attached to the panel
+- vcc-supply: phandle of the regulator that provides the vcc supply voltage.
+- iovcc-supply: phandle of the regulator that provides the iovcc supply
+  voltage.
 
 Example:
 

@@ -14,5 +17,7 @@ Example:
 			reg = <0>;
 			backlight = <&backlight>;
 			reset-gpios = <&gpio3 13 GPIO_ACTIVE_LOW>;
+			vcc-supply = <&reg_2v8_p>;
+			iovcc-supply = <&reg_1v8_p>;
 		};
 	};

Signature · 1 line

2.20.1

Allow to specify regulators for vcc and iovcc. According to the data sheet the panel wants vcc (2.8V) and iovcc (1.8V) and there's no startup dependency between the two.

Signed-off-by Guido Günther <[email protected]>

---
 .../drm/panel/panel-rocktech-jh057n00900.c    | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

drivers/gpu/drm/panel/panel-rocktech-jh057n00900.c +12 -0

index b8a069055fbc..f8f6f087b9bc 100644
@@ -15,6 +15,7 @@
 #include <linux/gpio/consumer.h>
 #include <linux/media-bus-format.h>
 #include <linux/module.h>
+#include <linux/regulator/consumer.h>
 #include <video/display_timing.h>
 #include <video/mipi_display.h>
 

@@ -47,6 +48,8 @@ struct jh057n {
 	struct drm_panel panel;
 	struct gpio_desc *reset_gpio;
 	struct backlight_device *backlight;
+	struct regulator *vcc;
+	struct regulator *iovcc;
 	bool prepared;
 
 	struct dentry *debugfs;

@@ -160,6 +163,8 @@ static int jh057n_unprepare(struct drm_panel *panel)
 		return 0;
 
 	mipi_dsi_dcs_set_display_off(dsi);
+	regulator_disable(ctx->iovcc);
+	regulator_disable(ctx->vcc);
 	ctx->prepared = false;
 
 	return 0;

@@ -174,6 +179,13 @@ static int jh057n_prepare(struct drm_panel *panel)
 		return 0;
 
 	DRM_DEV_DEBUG_DRIVER(ctx->dev, "Resetting the panel\n");
+	ret = regulator_enable(ctx->vcc);
+	if (ret < 0)
+		return ret;
+	ret = regulator_enable(ctx->iovcc);
+	if (ret < 0)
+		return ret;
+
 	gpiod_set_value_cansleep(ctx->reset_gpio, 1);
 	usleep_range(20, 40);
 	gpiod_set_value_cansleep(ctx->reset_gpio, 0);

Quoted 3 lines · Guido Günther

Allow to specify regulators for vcc and iovcc. According to the data sheet the panel wants vcc (2.8V) and iovcc (1.8V) and there's no startup dependency between the two.

s/jh057n0090/jh057n00900

Quoted 54 lines

Signed-off-by Guido Günther <[email protected]>

---
 .../drm/panel/panel-rocktech-jh057n00900.c    | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

drivers/gpu/drm/panel/panel-rocktech-jh057n00900.c +12 -0

index b8a069055fbc..f8f6f087b9bc 100644
@@ -15,6 +15,7 @@
 #include <linux/gpio/consumer.h>
 #include <linux/media-bus-format.h>
 #include <linux/module.h>
+#include <linux/regulator/consumer.h>
 #include <video/display_timing.h>
 #include <video/mipi_display.h>
 

@@ -47,6 +48,8 @@ struct jh057n {
 	struct drm_panel panel;
 	struct gpio_desc *reset_gpio;
 	struct backlight_device *backlight;
+	struct regulator *vcc;
+	struct regulator *iovcc;
 	bool prepared;
 
 	struct dentry *debugfs;

@@ -160,6 +163,8 @@ static int jh057n_unprepare(struct drm_panel *panel)
 		return 0;
 
 	mipi_dsi_dcs_set_display_off(dsi);
+	regulator_disable(ctx->iovcc);
+	regulator_disable(ctx->vcc);
 	ctx->prepared = false;
 
 	return 0;

@@ -174,6 +179,13 @@ static int jh057n_prepare(struct drm_panel *panel)
 		return 0;
 
 	DRM_DEV_DEBUG_DRIVER(ctx->dev, "Resetting the panel\n");
+	ret = regulator_enable(ctx->vcc);
+	if (ret < 0)
+		return ret;
+	ret = regulator_enable(ctx->iovcc);
+	if (ret < 0)
+		return ret;
+
 	gpiod_set_value_cansleep(ctx->reset_gpio, 1);
 	usleep_range(20, 40);
 	gpiod_set_value_cansleep(ctx->reset_gpio, 0);

@@ -301,6 +313,13 @@ static int jh057n_probe(struct mipi_dsi_device *dsi)
 	if (IS_ERR(ctx->backlight))
 		return PTR_ERR(ctx->backlight);
 

drivers/gpu/drm/panel/panel-rocktech-jh057n00900.c static int jh057n_probe(struct mipi_dsi_device *dsi) · line 322

Quoted 7 lines

drivers/gpu/drm/panel/panel-rocktech-jh057n00900.c +7 -0

+	ctx->vcc = devm_regulator_get(dev, "vcc");
+	if (IS_ERR(ctx->vcc))
+		return PTR_ERR(ctx->vcc);
+	ctx->iovcc = devm_regulator_get(dev, "iovcc");
+	if (IS_ERR(ctx->iovcc))
+		return PTR_ERR(ctx->iovcc);
+

Consider to write an error message.
The regulators are now mandatory, but they be missing in some device trees. So it would be good to help them to understand why it fails.

With this considered:

Reviewed-by Sam Ravnborg <[email protected]>

Sam