[PATCH 0/2] Add Truly NT35521 panel driver support

STALE1888d

9 messages, 3 authors, 2021-08-13 · open the first message on its own page

[PATCH 0/2] Add Truly NT35521 panel driver support

From: Shawn Guo <hidden>
Date: 2021-08-04 08:14:25

It adds a drm driver for Truly NT35521 5.24" 1280x720 DSI panel, which
can be found on Sony Xperia M4 Aqua phone.

Shawn Guo (2):
  dt-bindings: display: panel: Add Truly NT35521 panel support
  drm/panel: Add Truly NT35521 panel driver

 .../bindings/display/panel/truly,nt35521.yaml |  62 +++
 drivers/gpu/drm/panel/Kconfig                 |   9 +
 drivers/gpu/drm/panel/Makefile                |   1 +
 drivers/gpu/drm/panel/panel-truly-nt35521.c   | 491 ++++++++++++++++++
 4 files changed, 563 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml
 create mode 100644 drivers/gpu/drm/panel/panel-truly-nt35521.c

-- 
2.17.1

[PATCH 1/2] dt-bindings: display: panel: Add Truly NT35521 panel support

From: Shawn Guo <hidden>
Date: 2021-08-04 08:14:25

The Truly NT35521 is a 5.24" 1280x720 DSI panel, and the backlight is
managed through DSI link.

Signed-off-by: Shawn Guo <redacted>
---
 .../bindings/display/panel/truly,nt35521.yaml | 62 +++++++++++++++++++
 1 file changed, 62 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml

diff --git a/Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml b/Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml
new file mode 100644
index 000000000000..4727c3df6eb8
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml

@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/truly,nt35521.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Truly NT35521 5.24" 1280x720 MIPI-DSI Panel
+
+maintainers:
+  - Shawn Guo <shawn.guo@linaro.org>
+
+description: |
+  The Truly NT35521 is a 5.24" 1280x720 MIPI-DSI panel.  The panel backlight
+  is managed through DSI link.
+
+allOf:
+  - $ref: panel-common.yaml#
+
+properties:
+  compatible:
+    const: truly,nt35521
+
+  reg: true
+
+  reset-gpios: true
+
+  enable-gpios: true
+
+  pwr-positive5-gpios:
+    maxItems: 1
+
+  pwr-negative5-gpios:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - reset-gpios
+  - enable-gpios
+  - pwr-positive5-gpios
+  - pwr-negative5-gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    dsi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        panel@0 {
+            compatible = "truly,nt35521";
+            reg = <0>;
+            reset-gpios = <&msmgpio 25 GPIO_ACTIVE_LOW>;
+            pwr-positive5-gpios = <&msmgpio 114 GPIO_ACTIVE_HIGH>;
+            pwr-negative5-gpios = <&msmgpio 17 GPIO_ACTIVE_HIGH>;
+            enable-gpios = <&msmgpio 10 GPIO_ACTIVE_HIGH>;
+        };
+    };
+...

-- 
2.17.1

[PATCH 2/2] drm/panel: Add Truly NT35521 panel driver

From: Shawn Guo <hidden>
Date: 2021-08-04 08:14:28

It adds a drm driver for Truly NT35521 5.24" 1280x720 DSI panel, which
can be found on Sony Xperia M4 Aqua phone.  The panel backlight is
managed through DSI link.

Signed-off-by: Shawn Guo <redacted>
---
 drivers/gpu/drm/panel/Kconfig               |   9 +
 drivers/gpu/drm/panel/Makefile              |   1 +
 drivers/gpu/drm/panel/panel-truly-nt35521.c | 491 ++++++++++++++++++++
 3 files changed, 501 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-truly-nt35521.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index ef87d92cdf49..cdc4abd5c40c 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig

@@ -537,6 +537,15 @@ config DRM_PANEL_TPO_TPG110
 	  400CH LTPS TFT LCD Single Chip Digital Driver for up to
 	  800x400 LCD panels.
 
+config DRM_PANEL_TRULY_NT35521
+	tristate "Truly NT35521 panel"
+	depends on OF
+	depends on DRM_MIPI_DSI
+	depends on BACKLIGHT_CLASS_DEVICE
+	help
+	  Say Y here if you want to enable support for Truly NT35521
+	  1280x720 DSI panel.
+
 config DRM_PANEL_TRULY_NT35597_WQXGA
 	tristate "Truly WQXGA"
 	depends on OF

diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index cae4d976c069..3d3c98cb7a7b 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile

@@ -56,6 +56,7 @@ obj-$(CONFIG_DRM_PANEL_TDO_TL070WSH30) += panel-tdo-tl070wsh30.o
 obj-$(CONFIG_DRM_PANEL_TPO_TD028TTEC1) += panel-tpo-td028ttec1.o
 obj-$(CONFIG_DRM_PANEL_TPO_TD043MTEA1) += panel-tpo-td043mtea1.o
 obj-$(CONFIG_DRM_PANEL_TPO_TPG110) += panel-tpo-tpg110.o
+obj-$(CONFIG_DRM_PANEL_TRULY_NT35521) += panel-truly-nt35521.o
 obj-$(CONFIG_DRM_PANEL_TRULY_NT35597_WQXGA) += panel-truly-nt35597.o
 obj-$(CONFIG_DRM_PANEL_VISIONOX_RM69299) += panel-visionox-rm69299.o
 obj-$(CONFIG_DRM_PANEL_XINPENG_XPP055C272) += panel-xinpeng-xpp055c272.o

diff --git a/drivers/gpu/drm/panel/panel-truly-nt35521.c b/drivers/gpu/drm/panel/panel-truly-nt35521.c
new file mode 100644
index 000000000000..ea3cfb46be7e
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-truly-nt35521.c

@@ -0,0 +1,491 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2021, Linaro Limited
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+
+#include <video/mipi_display.h>
+
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_print.h>
+
+struct nt35521_panel {
+	struct drm_panel panel;
+	struct device *dev;
+	struct gpio_desc *rst_gpio;
+	struct gpio_desc *pwrp5_gpio;
+	struct gpio_desc *pwrn5_gpio;
+	struct gpio_desc *en_gpio;
+	bool prepared;
+	bool enabled;
+};
+
+static inline struct nt35521_panel *panel_to_nt35521(struct drm_panel *panel)
+{
+	return container_of(panel, struct nt35521_panel, panel);
+}
+
+#define nt_dcs_write(seq...)						\
+({									\
+	const u8 d[] = { seq };						\
+	if (mipi_dsi_dcs_write_buffer(dsi, d, ARRAY_SIZE(d)) < 0)	\
+		DRM_DEV_ERROR(dev, "dcs write buffer failed\n");	\
+})
+
+#define nt_gen_write(seq...)						\
+({									\
+	const u8 d[] = { seq };						\
+	if (mipi_dsi_generic_write(dsi, d, ARRAY_SIZE(d)) < 0)		\
+		DRM_DEV_ERROR(dev, "generic write buffer failed\n");	\
+})
+
+static void nt35521_panel_on(struct nt35521_panel *nt)
+{
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
+	struct device *dev = nt->dev;
+
+	/* Transmit data in low power mode */
+	dsi->mode_flags |= MIPI_DSI_MODE_LPM;
+
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	nt_dcs_write(0xff, 0xaa, 0x55, 0xa5, 0x80);
+	nt_dcs_write(0x6f, 0x11, 0x00);
+	nt_dcs_write(0xf7, 0x20, 0x00);
+	nt_dcs_write(0x6f, 0x01);
+	nt_dcs_write(0xb1, 0x21);
+	nt_dcs_write(0xbd, 0x01, 0xa0, 0x10, 0x08, 0x01);
+	nt_dcs_write(0xb8, 0x01, 0x02, 0x0c, 0x02);
+	nt_dcs_write(0xbb, 0x11, 0x11);
+	nt_dcs_write(0xbc, 0x00, 0x00);
+	nt_dcs_write(0xb6, 0x02);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x01);
+	nt_dcs_write(0xb0, 0x09, 0x09);
+	nt_dcs_write(0xb1, 0x09, 0x09);
+	nt_dcs_write(0xbc, 0x8c, 0x00);
+	nt_dcs_write(0xbd, 0x8c, 0x00);
+	nt_dcs_write(0xca, 0x00);
+	nt_dcs_write(0xc0, 0x04);
+	nt_dcs_write(0xbe, 0xb5);
+	nt_dcs_write(0xb3, 0x35, 0x35);
+	nt_dcs_write(0xb4, 0x25, 0x25);
+	nt_dcs_write(0xb9, 0x43, 0x43);
+	nt_dcs_write(0xba, 0x24, 0x24);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x02);
+	nt_dcs_write(0xee, 0x03);
+	nt_dcs_write(0xb0, 0x00, 0xb2, 0x00, 0xb3, 0x00, 0xb6, 0x00,
+		     0xc3, 0x00, 0xce, 0x00, 0xe1, 0x00, 0xf3, 0x01,
+		     0x11);
+	nt_dcs_write(0xb1, 0x01, 0x2e, 0x01, 0x5c, 0x01, 0x82, 0x01,
+		     0xc3, 0x01, 0xfe, 0x02, 0x00, 0x02, 0x37, 0x02,
+		     0x77);
+	nt_dcs_write(0xb2, 0x02, 0xa1, 0x02, 0xd7, 0x02, 0xfe, 0x03,
+		     0x2c, 0x03, 0x4b, 0x03, 0x63, 0x03, 0x8f, 0x03,
+		     0x90);
+	nt_dcs_write(0xb3, 0x03, 0x96, 0x03, 0x98);
+	nt_dcs_write(0xb4, 0x00, 0x81, 0x00, 0x8b, 0x00, 0x9c, 0x00,
+		     0xa9, 0x00, 0xb5, 0x00, 0xcb, 0x00, 0xdf, 0x01,
+		     0x02);
+	nt_dcs_write(0xb5, 0x01, 0x1f, 0x01, 0x51, 0x01, 0x7a, 0x01,
+		     0xbf, 0x01, 0xfa, 0x01, 0xfc, 0x02, 0x34, 0x02, 0x76);
+	nt_dcs_write(0xb6, 0x02, 0x9f, 0x02, 0xd7, 0x02, 0xfc, 0x03, 0x2c,
+		     0x03, 0x4a, 0x03, 0x63, 0x03, 0x8f, 0x03, 0xa2);
+	nt_dcs_write(0xb7, 0x03, 0xb8, 0x03, 0xba);
+	nt_dcs_write(0xb8, 0x00, 0x01, 0x00, 0x02, 0x00, 0x0e, 0x00, 0x2a,
+		     0x00, 0x41, 0x00, 0x67, 0x00, 0x87, 0x00, 0xb9);
+	nt_dcs_write(0xb9, 0x00, 0xe2, 0x01, 0x22, 0x01, 0x54, 0x01, 0xa3,
+		     0x01, 0xe6, 0x01, 0xe7, 0x02, 0x24, 0x02, 0x67);
+	nt_dcs_write(0xba, 0x02, 0x93, 0x02, 0xcd, 0x02, 0xf6, 0x03, 0x31,
+		     0x03, 0x6c, 0x03, 0xe9, 0x03, 0xef, 0x03, 0xf4);
+	nt_dcs_write(0xbb, 0x03, 0xf6, 0x03, 0xf7);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x03);
+	nt_dcs_write(0xb0, 0x22, 0x00);
+	nt_dcs_write(0xb1, 0x22, 0x00);
+	nt_dcs_write(0xb2, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xb3, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xb4, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xb5, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xba, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xbb, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xbc, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xbd, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xc0, 0x00, 0x34, 0x00, 0x00);
+	nt_dcs_write(0xc1, 0x00, 0x00, 0x34, 0x00);
+	nt_dcs_write(0xc2, 0x00, 0x00, 0x34, 0x00);
+	nt_dcs_write(0xc3, 0x00, 0x00, 0x34, 0x00);
+	nt_dcs_write(0xc4, 0x60);
+	nt_dcs_write(0xc5, 0xc0);
+	nt_dcs_write(0xc6, 0x00);
+	nt_dcs_write(0xc7, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x05);
+	nt_dcs_write(0xb0, 0x17, 0x06);
+	nt_dcs_write(0xb1, 0x17, 0x06);
+	nt_dcs_write(0xb2, 0x17, 0x06);
+	nt_dcs_write(0xb3, 0x17, 0x06);
+	nt_dcs_write(0xb4, 0x17, 0x06);
+	nt_dcs_write(0xb5, 0x17, 0x06);
+	nt_dcs_write(0xb6, 0x17, 0x06);
+	nt_dcs_write(0xb7, 0x17, 0x06);
+	nt_dcs_write(0xb8, 0x00);
+	nt_dcs_write(0xb9, 0x00, 0x03);
+	nt_dcs_write(0xba, 0x00, 0x00);
+	nt_dcs_write(0xbb, 0x02, 0x03);
+	nt_dcs_write(0xbc, 0x02, 0x03);
+	nt_dcs_write(0xbd, 0x03, 0x03, 0x00, 0x03, 0x03);
+	nt_dcs_write(0xc0, 0x0b);
+	nt_dcs_write(0xc1, 0x09);
+	nt_dcs_write(0xc2, 0xa6);
+	nt_dcs_write(0xc3, 0x05);
+	nt_dcs_write(0xc4, 0x00);
+	nt_dcs_write(0xc5, 0x02);
+	nt_dcs_write(0xc6, 0x22);
+	nt_dcs_write(0xc7, 0x03);
+	nt_dcs_write(0xc8, 0x07, 0x20);
+	nt_dcs_write(0xc9, 0x03, 0x20);
+	nt_dcs_write(0xca, 0x01, 0x60);
+	nt_dcs_write(0xcb, 0x01, 0x60);
+	nt_dcs_write(0xcc, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xcd, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xce, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xcf, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xd1, 0x00, 0x05, 0x01, 0x07, 0x10);
+	nt_dcs_write(0xd2, 0x10, 0x05, 0x05, 0x03, 0x10);
+	nt_dcs_write(0xd3, 0x20, 0x00, 0x43, 0x07, 0x10);
+	nt_dcs_write(0xd4, 0x30, 0x00, 0x43, 0x07, 0x10);
+	nt_dcs_write(0xd0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd5, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		     0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd6, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		     0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd7, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		     0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd8, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xe5, 0x06);
+	nt_dcs_write(0xe6, 0x06);
+	nt_dcs_write(0xe7, 0x00);
+	nt_dcs_write(0xe8, 0x06);
+	nt_dcs_write(0xe9, 0x06);
+	nt_dcs_write(0xea, 0x06);
+	nt_dcs_write(0xeb, 0x00);
+	nt_dcs_write(0xec, 0x00);
+	nt_dcs_write(0xed, 0x30);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x06);
+	nt_dcs_write(0xb0, 0x31, 0x31);
+	nt_dcs_write(0xb1, 0x31, 0x31);
+	nt_dcs_write(0xb2, 0x2d, 0x2e);
+	nt_dcs_write(0xb3, 0x31, 0x34);
+	nt_dcs_write(0xb4, 0x29, 0x2a);
+	nt_dcs_write(0xb5, 0x12, 0x10);
+	nt_dcs_write(0xb6, 0x18, 0x16);
+	nt_dcs_write(0xb7, 0x00, 0x02);
+	nt_dcs_write(0xb8, 0x08, 0x31);
+	nt_dcs_write(0xb9, 0x31, 0x31);
+	nt_dcs_write(0xba, 0x31, 0x31);
+	nt_dcs_write(0xbb, 0x31, 0x08);
+	nt_dcs_write(0xbc, 0x03, 0x01);
+	nt_dcs_write(0xbd, 0x17, 0x19);
+	nt_dcs_write(0xbe, 0x11, 0x13);
+	nt_dcs_write(0xbf, 0x2a, 0x29);
+	nt_dcs_write(0xc0, 0x34, 0x31);
+	nt_dcs_write(0xc1, 0x2e, 0x2d);
+	nt_dcs_write(0xc2, 0x31, 0x31);
+	nt_dcs_write(0xc3, 0x31, 0x31);
+	nt_dcs_write(0xc4, 0x31, 0x31);
+	nt_dcs_write(0xc5, 0x31, 0x31);
+	nt_dcs_write(0xc6, 0x2e, 0x2d);
+	nt_dcs_write(0xc7, 0x31, 0x34);
+	nt_dcs_write(0xc8, 0x29, 0x2a);
+	nt_dcs_write(0xc9, 0x17, 0x19);
+	nt_dcs_write(0xca, 0x11, 0x13);
+	nt_dcs_write(0xcb, 0x03, 0x01);
+	nt_dcs_write(0xcc, 0x08, 0x31);
+	nt_dcs_write(0xcd, 0x31, 0x31);
+	nt_dcs_write(0xce, 0x31, 0x31);
+	nt_dcs_write(0xcf, 0x31, 0x08);
+	nt_dcs_write(0xd0, 0x00, 0x02);
+	nt_dcs_write(0xd1, 0x12, 0x10);
+	nt_dcs_write(0xd2, 0x18, 0x16);
+	nt_dcs_write(0xd3, 0x2a, 0x29);
+	nt_dcs_write(0xd4, 0x34, 0x31);
+	nt_dcs_write(0xd5, 0x2d, 0x2e);
+	nt_dcs_write(0xd6, 0x31, 0x31);
+	nt_dcs_write(0xd7, 0x31, 0x31);
+	nt_dcs_write(0xe5, 0x31, 0x31);
+	nt_dcs_write(0xe6, 0x31, 0x31);
+	nt_dcs_write(0xd8, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd9, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xe7, 0x00);
+	nt_dcs_write(0x6f, 0x02);
+	nt_dcs_write(0xf7, 0x47);
+	nt_dcs_write(0x6f, 0x0a);
+	nt_dcs_write(0xf7, 0x02);
+	nt_dcs_write(0x6f, 0x17);
+	nt_dcs_write(0xf4, 0x60);
+	nt_dcs_write(0x6f, 0x01);
+	nt_dcs_write(0xf9, 0x46);
+	nt_dcs_write(0x6f, 0x11);
+	nt_dcs_write(0xf3, 0x01);
+	nt_dcs_write(0x35, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	nt_dcs_write(0xd9, 0x02, 0x03, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x00, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	nt_dcs_write(0xb1, 0x6c, 0x21);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x00, 0x00);
+	nt_dcs_write(0x35, 0x00);
+	nt_gen_write(0x11, 0x00);
+	msleep(120);
+	nt_gen_write(0x29, 0x00);
+	usleep_range(1000, 1500);
+	nt_dcs_write(0x53, 0x24);
+}
+
+static void nt35521_panel_off(struct nt35521_panel *nt)
+{
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
+	struct device *dev = nt->dev;
+
+	/* Transmit data in high speed mode */
+	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
+
+	nt_dcs_write(0x28, 0x00);
+	msleep(50);
+	nt_dcs_write(0x10, 0x00);
+	msleep(150);
+}
+
+static int nt35521_prepare(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (nt->prepared)
+		return 0;
+
+	gpiod_set_value_cansleep(nt->pwrp5_gpio, 1);
+	usleep_range(1000, 1500);
+	gpiod_set_value_cansleep(nt->pwrn5_gpio, 1);
+	usleep_range(10000, 15000);
+	gpiod_set_value_cansleep(nt->rst_gpio, 0);
+	msleep(150);
+
+	nt35521_panel_on(nt);
+
+	nt->prepared = true;
+
+	return 0;
+}
+
+static int nt35521_unprepare(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (!nt->prepared)
+		return 0;
+
+	nt35521_panel_off(nt);
+
+	gpiod_set_value_cansleep(nt->rst_gpio, 1);
+
+	nt->prepared = false;
+
+	return 0;
+}
+
+static int nt35521_enable(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (nt->enabled)
+		return 0;
+
+	gpiod_set_value_cansleep(nt->en_gpio, 1);
+
+	nt->enabled = true;
+
+	return 0;
+}
+
+static int nt35521_disable(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (!nt->enabled)
+		return 0;
+
+	gpiod_set_value_cansleep(nt->en_gpio, 0);
+
+	nt->enabled = false;
+
+	return 0;
+}
+
+static const struct drm_display_mode nt35521_modes = {
+	.clock = 133306,
+	.hdisplay = 720,
+	.hsync_start = 720 + 632,
+	.hsync_end = 720 + 632 + 40,
+	.htotal = 720 + 632 + 40 + 295,
+	.vdisplay = 1280,
+	.vsync_start = 1280 + 18,
+	.vsync_end = 1280 + 18 + 1,
+	.vtotal = 1280 + 18 + 1 + 18,
+};
+
+static int nt35521_get_modes(struct drm_panel *panel,
+			      struct drm_connector *connector)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+	struct drm_display_mode *mode;
+
+	mode = drm_mode_duplicate(connector->dev, &nt35521_modes);
+	if (!mode) {
+		DRM_DEV_ERROR(nt->dev, "failed to add display mode\n");
+		return -ENOMEM;
+	}
+
+	drm_mode_set_name(mode);
+	drm_mode_probed_add(connector, mode);
+
+	connector->display_info.width_mm = 65;
+	connector->display_info.height_mm = 116;
+
+	return 1;
+}
+
+static const struct drm_panel_funcs nt35521_drm_funcs = {
+	.prepare = nt35521_prepare,
+	.unprepare = nt35521_unprepare,
+	.enable = nt35521_enable,
+	.disable = nt35521_disable,
+	.get_modes = nt35521_get_modes,
+};
+
+static int nt35521_backlight_update_status(struct backlight_device *bd)
+{
+	struct nt35521_panel *nt = bl_get_data(bd);
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
+	u8 brightness = bd->props.brightness;
+	int ret;
+
+	ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
+				 &brightness,
+				 sizeof(brightness));
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static const struct backlight_ops nt35521_backlight_ops = {
+	.update_status = nt35521_backlight_update_status,
+};
+
+static int nt35521_probe(struct mipi_dsi_device *dsi)
+{
+	struct backlight_properties props;
+	struct device *dev = &dsi->dev;
+	struct nt35521_panel *nt;
+	int ret;
+
+	nt = devm_kzalloc(dev, sizeof(*nt), GFP_KERNEL);
+	if (!nt)
+		return -ENOMEM;
+
+	nt->rst_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->rst_gpio)) {
+		ret = PTR_ERR(nt->rst_gpio);
+		DRM_DEV_ERROR(dev, "failed to get reset GPIO: %d\n", ret);
+		return ret;
+	}
+
+	nt->pwrp5_gpio = devm_gpiod_get(dev, "pwr-positive5", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->pwrp5_gpio)) {
+		ret = PTR_ERR(nt->pwrp5_gpio);
+		DRM_DEV_ERROR(dev, "failed to get positive5 GPIO: %d\n", ret);
+		return ret;
+	}
+
+	nt->pwrn5_gpio = devm_gpiod_get(dev, "pwr-negative5", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->pwrn5_gpio)) {
+		ret = PTR_ERR(nt->pwrn5_gpio);
+		DRM_DEV_ERROR(dev, "failed to get negative5 GPIO: %d\n", ret);
+		return ret;
+	}
+
+	nt->en_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->en_gpio)) {
+		ret = PTR_ERR(nt->en_gpio);
+		DRM_DEV_ERROR(dev, "failed to get enable GPIO: %d\n", ret);
+		return ret;
+	}
+
+	nt->dev = dev;
+
+	drm_panel_init(&nt->panel, dev, &nt35521_drm_funcs,
+		       DRM_MODE_CONNECTOR_DSI);
+
+	props.max_brightness = 255;
+	props.brightness = 240;
+	props.type = BACKLIGHT_RAW;
+
+	nt->panel.backlight = devm_backlight_device_register(dev, dev_name(dev),
+						dev, nt, &nt35521_backlight_ops,
+						&props);
+	if (IS_ERR(nt->panel.backlight)) {
+		ret = PTR_ERR(nt->panel.backlight);
+		DRM_DEV_ERROR(dev, "failed to register backlight: %d\n", ret);
+		return ret;
+	}
+
+	drm_panel_add(&nt->panel);
+
+	dsi->lanes = 4;
+	dsi->format = MIPI_DSI_FMT_RGB888;
+	dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
+			  MIPI_DSI_CLOCK_NON_CONTINUOUS;
+
+	ret = mipi_dsi_attach(dsi);
+	if (ret < 0) {
+		DRM_DEV_ERROR(dev, "failed to attach DSI device: %d\n", ret);
+		drm_panel_remove(&nt->panel);
+		return ret;
+	}
+
+	mipi_dsi_set_drvdata(dsi, nt);
+
+	return 0;
+}
+
+static int nt35521_remove(struct mipi_dsi_device *dsi)
+{
+	struct nt35521_panel *nt = mipi_dsi_get_drvdata(dsi);
+
+	mipi_dsi_detach(dsi);
+	drm_panel_remove(&nt->panel);
+
+	return 0;
+}
+
+static const struct of_device_id truly_nt35521_of_match[] = {
+	{ .compatible = "truly,nt35521" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, truly_nt35521_of_match);
+
+static struct mipi_dsi_driver truly_nt35521_driver = {
+	.driver = {
+		.name = "panel-truly-nt35521",
+		.of_match_table = truly_nt35521_of_match,
+	},
+	.probe  = nt35521_probe,
+	.remove = nt35521_remove,
+};
+module_mipi_dsi_driver(truly_nt35521_driver);
+
+MODULE_DESCRIPTION("Truly NT35521 DSI panel driver");
+MODULE_LICENSE("GPL v2");

-- 
2.17.1

Re: [PATCH 2/2] drm/panel: Add Truly NT35521 panel driver

From: Stephan Gerhold <stephan@gerhold.net>
Date: 2021-08-04 12:09:31

Hi Shawn,

Thanks for the patch!

On Wed, Aug 04, 2021 at 04:13:52PM +0800, Shawn Guo wrote:

quoted hunk

It adds a drm driver for Truly NT35521 5.24" 1280x720 DSI panel, which
can be found on Sony Xperia M4 Aqua phone.  The panel backlight is
managed through DSI link.

Signed-off-by: Shawn Guo <redacted>
---
 drivers/gpu/drm/panel/Kconfig               |   9 +
 drivers/gpu/drm/panel/Makefile              |   1 +
 drivers/gpu/drm/panel/panel-truly-nt35521.c | 491 ++++++++++++++++++++
 3 files changed, 501 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-truly-nt35521.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index ef87d92cdf49..cdc4abd5c40c 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig

@@ -537,6 +537,15 @@ config DRM_PANEL_TPO_TPG110
 	  400CH LTPS TFT LCD Single Chip Digital Driver for up to
 	  800x400 LCD panels.
 
+config DRM_PANEL_TRULY_NT35521
+	tristate "Truly NT35521 panel"

I think the name "Truly NT35521" is a bit too generic. AFAIK "Truly" is
a panel vendor and the NovaTek NT35521 is the panel controller. But
there are almost certainly other Truly panels that were also combined
with a NT35521 but need a slightly different configuration.

If you don't know more than "Truly NT35521" based on the Sony sources,
maybe do it similar to "asus,z00t-tm5p5-n35596" and use a compatible
like "sony,<device>-truly-nt35521". Would be good to clarify the Kconfig
option here too.

quoted hunk

+	depends on OF
+	depends on DRM_MIPI_DSI
+	depends on BACKLIGHT_CLASS_DEVICE
+	help
+	  Say Y here if you want to enable support for Truly NT35521
+	  1280x720 DSI panel.
+
 config DRM_PANEL_TRULY_NT35597_WQXGA
 	tristate "Truly WQXGA"
 	depends on OF

diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index cae4d976c069..3d3c98cb7a7b 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile

@@ -56,6 +56,7 @@ obj-$(CONFIG_DRM_PANEL_TDO_TL070WSH30) += panel-tdo-tl070wsh30.o
 obj-$(CONFIG_DRM_PANEL_TPO_TD028TTEC1) += panel-tpo-td028ttec1.o
 obj-$(CONFIG_DRM_PANEL_TPO_TD043MTEA1) += panel-tpo-td043mtea1.o
 obj-$(CONFIG_DRM_PANEL_TPO_TPG110) += panel-tpo-tpg110.o
+obj-$(CONFIG_DRM_PANEL_TRULY_NT35521) += panel-truly-nt35521.o
 obj-$(CONFIG_DRM_PANEL_TRULY_NT35597_WQXGA) += panel-truly-nt35597.o
 obj-$(CONFIG_DRM_PANEL_VISIONOX_RM69299) += panel-visionox-rm69299.o
 obj-$(CONFIG_DRM_PANEL_XINPENG_XPP055C272) += panel-xinpeng-xpp055c272.o

diff --git a/drivers/gpu/drm/panel/panel-truly-nt35521.c b/drivers/gpu/drm/panel/panel-truly-nt35521.c
new file mode 100644
index 000000000000..ea3cfb46be7e
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-truly-nt35521.c

@@ -0,0 +1,491 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2021, Linaro Limited
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+
+#include <video/mipi_display.h>
+
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_print.h>
+
+struct nt35521_panel {
+	struct drm_panel panel;
+	struct device *dev;
+	struct gpio_desc *rst_gpio;
+	struct gpio_desc *pwrp5_gpio;
+	struct gpio_desc *pwrn5_gpio;
+	struct gpio_desc *en_gpio;
+	bool prepared;
+	bool enabled;
+};
+
+static inline struct nt35521_panel *panel_to_nt35521(struct drm_panel *panel)
+{
+	return container_of(panel, struct nt35521_panel, panel);
+}
+
+#define nt_dcs_write(seq...)						\
+({									\
+	const u8 d[] = { seq };						\
+	if (mipi_dsi_dcs_write_buffer(dsi, d, ARRAY_SIZE(d)) < 0)	\
+		DRM_DEV_ERROR(dev, "dcs write buffer failed\n");	\
+})
+
+#define nt_gen_write(seq...)						\
+({									\
+	const u8 d[] = { seq };						\
+	if (mipi_dsi_generic_write(dsi, d, ARRAY_SIZE(d)) < 0)		\
+		DRM_DEV_ERROR(dev, "generic write buffer failed\n");	\
+})
+
+static void nt35521_panel_on(struct nt35521_panel *nt)
+{
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
+	struct device *dev = nt->dev;
+
+	/* Transmit data in low power mode */
+	dsi->mode_flags |= MIPI_DSI_MODE_LPM;
+
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	nt_dcs_write(0xff, 0xaa, 0x55, 0xa5, 0x80);
+	nt_dcs_write(0x6f, 0x11, 0x00);
+	nt_dcs_write(0xf7, 0x20, 0x00);
+	nt_dcs_write(0x6f, 0x01);
+	nt_dcs_write(0xb1, 0x21);
+	nt_dcs_write(0xbd, 0x01, 0xa0, 0x10, 0x08, 0x01);
+	nt_dcs_write(0xb8, 0x01, 0x02, 0x0c, 0x02);
+	nt_dcs_write(0xbb, 0x11, 0x11);
+	nt_dcs_write(0xbc, 0x00, 0x00);
+	nt_dcs_write(0xb6, 0x02);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x01);
+	nt_dcs_write(0xb0, 0x09, 0x09);
+	nt_dcs_write(0xb1, 0x09, 0x09);
+	nt_dcs_write(0xbc, 0x8c, 0x00);
+	nt_dcs_write(0xbd, 0x8c, 0x00);
+	nt_dcs_write(0xca, 0x00);
+	nt_dcs_write(0xc0, 0x04);
+	nt_dcs_write(0xbe, 0xb5);
+	nt_dcs_write(0xb3, 0x35, 0x35);
+	nt_dcs_write(0xb4, 0x25, 0x25);
+	nt_dcs_write(0xb9, 0x43, 0x43);
+	nt_dcs_write(0xba, 0x24, 0x24);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x02);
+	nt_dcs_write(0xee, 0x03);
+	nt_dcs_write(0xb0, 0x00, 0xb2, 0x00, 0xb3, 0x00, 0xb6, 0x00,
+		     0xc3, 0x00, 0xce, 0x00, 0xe1, 0x00, 0xf3, 0x01,
+		     0x11);
+	nt_dcs_write(0xb1, 0x01, 0x2e, 0x01, 0x5c, 0x01, 0x82, 0x01,
+		     0xc3, 0x01, 0xfe, 0x02, 0x00, 0x02, 0x37, 0x02,
+		     0x77);
+	nt_dcs_write(0xb2, 0x02, 0xa1, 0x02, 0xd7, 0x02, 0xfe, 0x03,
+		     0x2c, 0x03, 0x4b, 0x03, 0x63, 0x03, 0x8f, 0x03,
+		     0x90);
+	nt_dcs_write(0xb3, 0x03, 0x96, 0x03, 0x98);
+	nt_dcs_write(0xb4, 0x00, 0x81, 0x00, 0x8b, 0x00, 0x9c, 0x00,
+		     0xa9, 0x00, 0xb5, 0x00, 0xcb, 0x00, 0xdf, 0x01,
+		     0x02);
+	nt_dcs_write(0xb5, 0x01, 0x1f, 0x01, 0x51, 0x01, 0x7a, 0x01,
+		     0xbf, 0x01, 0xfa, 0x01, 0xfc, 0x02, 0x34, 0x02, 0x76);
+	nt_dcs_write(0xb6, 0x02, 0x9f, 0x02, 0xd7, 0x02, 0xfc, 0x03, 0x2c,
+		     0x03, 0x4a, 0x03, 0x63, 0x03, 0x8f, 0x03, 0xa2);
+	nt_dcs_write(0xb7, 0x03, 0xb8, 0x03, 0xba);
+	nt_dcs_write(0xb8, 0x00, 0x01, 0x00, 0x02, 0x00, 0x0e, 0x00, 0x2a,
+		     0x00, 0x41, 0x00, 0x67, 0x00, 0x87, 0x00, 0xb9);
+	nt_dcs_write(0xb9, 0x00, 0xe2, 0x01, 0x22, 0x01, 0x54, 0x01, 0xa3,
+		     0x01, 0xe6, 0x01, 0xe7, 0x02, 0x24, 0x02, 0x67);
+	nt_dcs_write(0xba, 0x02, 0x93, 0x02, 0xcd, 0x02, 0xf6, 0x03, 0x31,
+		     0x03, 0x6c, 0x03, 0xe9, 0x03, 0xef, 0x03, 0xf4);
+	nt_dcs_write(0xbb, 0x03, 0xf6, 0x03, 0xf7);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x03);
+	nt_dcs_write(0xb0, 0x22, 0x00);
+	nt_dcs_write(0xb1, 0x22, 0x00);
+	nt_dcs_write(0xb2, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xb3, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xb4, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xb5, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xba, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xbb, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xbc, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xbd, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xc0, 0x00, 0x34, 0x00, 0x00);
+	nt_dcs_write(0xc1, 0x00, 0x00, 0x34, 0x00);
+	nt_dcs_write(0xc2, 0x00, 0x00, 0x34, 0x00);
+	nt_dcs_write(0xc3, 0x00, 0x00, 0x34, 0x00);
+	nt_dcs_write(0xc4, 0x60);
+	nt_dcs_write(0xc5, 0xc0);
+	nt_dcs_write(0xc6, 0x00);
+	nt_dcs_write(0xc7, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x05);
+	nt_dcs_write(0xb0, 0x17, 0x06);
+	nt_dcs_write(0xb1, 0x17, 0x06);
+	nt_dcs_write(0xb2, 0x17, 0x06);
+	nt_dcs_write(0xb3, 0x17, 0x06);
+	nt_dcs_write(0xb4, 0x17, 0x06);
+	nt_dcs_write(0xb5, 0x17, 0x06);
+	nt_dcs_write(0xb6, 0x17, 0x06);
+	nt_dcs_write(0xb7, 0x17, 0x06);
+	nt_dcs_write(0xb8, 0x00);
+	nt_dcs_write(0xb9, 0x00, 0x03);
+	nt_dcs_write(0xba, 0x00, 0x00);
+	nt_dcs_write(0xbb, 0x02, 0x03);
+	nt_dcs_write(0xbc, 0x02, 0x03);
+	nt_dcs_write(0xbd, 0x03, 0x03, 0x00, 0x03, 0x03);
+	nt_dcs_write(0xc0, 0x0b);
+	nt_dcs_write(0xc1, 0x09);
+	nt_dcs_write(0xc2, 0xa6);
+	nt_dcs_write(0xc3, 0x05);
+	nt_dcs_write(0xc4, 0x00);
+	nt_dcs_write(0xc5, 0x02);
+	nt_dcs_write(0xc6, 0x22);
+	nt_dcs_write(0xc7, 0x03);
+	nt_dcs_write(0xc8, 0x07, 0x20);
+	nt_dcs_write(0xc9, 0x03, 0x20);
+	nt_dcs_write(0xca, 0x01, 0x60);
+	nt_dcs_write(0xcb, 0x01, 0x60);
+	nt_dcs_write(0xcc, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xcd, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xce, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xcf, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xd1, 0x00, 0x05, 0x01, 0x07, 0x10);
+	nt_dcs_write(0xd2, 0x10, 0x05, 0x05, 0x03, 0x10);
+	nt_dcs_write(0xd3, 0x20, 0x00, 0x43, 0x07, 0x10);
+	nt_dcs_write(0xd4, 0x30, 0x00, 0x43, 0x07, 0x10);
+	nt_dcs_write(0xd0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd5, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		     0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd6, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		     0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd7, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		     0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd8, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xe5, 0x06);
+	nt_dcs_write(0xe6, 0x06);
+	nt_dcs_write(0xe7, 0x00);
+	nt_dcs_write(0xe8, 0x06);
+	nt_dcs_write(0xe9, 0x06);
+	nt_dcs_write(0xea, 0x06);
+	nt_dcs_write(0xeb, 0x00);
+	nt_dcs_write(0xec, 0x00);
+	nt_dcs_write(0xed, 0x30);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x06);
+	nt_dcs_write(0xb0, 0x31, 0x31);
+	nt_dcs_write(0xb1, 0x31, 0x31);
+	nt_dcs_write(0xb2, 0x2d, 0x2e);
+	nt_dcs_write(0xb3, 0x31, 0x34);
+	nt_dcs_write(0xb4, 0x29, 0x2a);
+	nt_dcs_write(0xb5, 0x12, 0x10);
+	nt_dcs_write(0xb6, 0x18, 0x16);
+	nt_dcs_write(0xb7, 0x00, 0x02);
+	nt_dcs_write(0xb8, 0x08, 0x31);
+	nt_dcs_write(0xb9, 0x31, 0x31);
+	nt_dcs_write(0xba, 0x31, 0x31);
+	nt_dcs_write(0xbb, 0x31, 0x08);
+	nt_dcs_write(0xbc, 0x03, 0x01);
+	nt_dcs_write(0xbd, 0x17, 0x19);
+	nt_dcs_write(0xbe, 0x11, 0x13);
+	nt_dcs_write(0xbf, 0x2a, 0x29);
+	nt_dcs_write(0xc0, 0x34, 0x31);
+	nt_dcs_write(0xc1, 0x2e, 0x2d);
+	nt_dcs_write(0xc2, 0x31, 0x31);
+	nt_dcs_write(0xc3, 0x31, 0x31);
+	nt_dcs_write(0xc4, 0x31, 0x31);
+	nt_dcs_write(0xc5, 0x31, 0x31);
+	nt_dcs_write(0xc6, 0x2e, 0x2d);
+	nt_dcs_write(0xc7, 0x31, 0x34);
+	nt_dcs_write(0xc8, 0x29, 0x2a);
+	nt_dcs_write(0xc9, 0x17, 0x19);
+	nt_dcs_write(0xca, 0x11, 0x13);
+	nt_dcs_write(0xcb, 0x03, 0x01);
+	nt_dcs_write(0xcc, 0x08, 0x31);
+	nt_dcs_write(0xcd, 0x31, 0x31);
+	nt_dcs_write(0xce, 0x31, 0x31);
+	nt_dcs_write(0xcf, 0x31, 0x08);
+	nt_dcs_write(0xd0, 0x00, 0x02);
+	nt_dcs_write(0xd1, 0x12, 0x10);
+	nt_dcs_write(0xd2, 0x18, 0x16);
+	nt_dcs_write(0xd3, 0x2a, 0x29);
+	nt_dcs_write(0xd4, 0x34, 0x31);
+	nt_dcs_write(0xd5, 0x2d, 0x2e);
+	nt_dcs_write(0xd6, 0x31, 0x31);
+	nt_dcs_write(0xd7, 0x31, 0x31);
+	nt_dcs_write(0xe5, 0x31, 0x31);
+	nt_dcs_write(0xe6, 0x31, 0x31);
+	nt_dcs_write(0xd8, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd9, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xe7, 0x00);
+	nt_dcs_write(0x6f, 0x02);
+	nt_dcs_write(0xf7, 0x47);
+	nt_dcs_write(0x6f, 0x0a);
+	nt_dcs_write(0xf7, 0x02);
+	nt_dcs_write(0x6f, 0x17);
+	nt_dcs_write(0xf4, 0x60);
+	nt_dcs_write(0x6f, 0x01);
+	nt_dcs_write(0xf9, 0x46);
+	nt_dcs_write(0x6f, 0x11);
+	nt_dcs_write(0xf3, 0x01);
+	nt_dcs_write(0x35, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	nt_dcs_write(0xd9, 0x02, 0x03, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x00, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	nt_dcs_write(0xb1, 0x6c, 0x21);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x00, 0x00);
+	nt_dcs_write(0x35, 0x00);
+	nt_gen_write(0x11, 0x00);
+	msleep(120);
+	nt_gen_write(0x29, 0x00);
+	usleep_range(1000, 1500);
+	nt_dcs_write(0x53, 0x24);

Did you mix up "nt_dcs_write" and "nt_gen_write" here?
The nt_gen_write(0x11, 0x00); looks like MIPI_DCS_EXIT_SLEEP_MODE
and the nt_gen_write(0x29, 0x00); looks like MIPI_DCS_SET_DISPLAY_ON.

For reference you can pull your original reference DTB from Sony through
my panel driver generator: https://github.com/msm8916-mainline/linux-mdss-dsi-panel-driver-generator

It produces the following (I compiled "msm8939-kanuti_tulip.dtb"
from https://github.com/sonyxperiadev/kernel/tree/aosp/LA.BR.1.3.3_rb2.14,
not sure if that is right):

	// ...
	dsi_generic_write_seq(dsi, 0x35, 0x00);

	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
	if (ret < 0) {
		dev_err(dev, "Failed to exit sleep mode: %d\n", ret);
		return ret;
	}
	msleep(120);

	ret = mipi_dsi_dcs_set_display_on(dsi);
	if (ret < 0) {
		dev_err(dev, "Failed to set display on: %d\n", ret);
		return ret;
	}
	usleep_range(1000, 2000);

	dsi_generic_write_seq(dsi, 0x53, 0x24);

Which also suggests that generic and DCS writes are mixed up here.

Note however that you could not use the generated driver as-is,
because Sony seems to use their own display driver instead of Qualcomm's
and some things seem to be different.

quoted hunk

+}
+
+static void nt35521_panel_off(struct nt35521_panel *nt)
+{
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
+	struct device *dev = nt->dev;
+
+	/* Transmit data in high speed mode */
+	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
+
+	nt_dcs_write(0x28, 0x00);
+	msleep(50);
+	nt_dcs_write(0x10, 0x00);
+	msleep(150);

A bit more deobfuscated from the panel driver generator:

	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;

	ret = mipi_dsi_dcs_set_display_off(dsi);
	if (ret < 0) {
		dev_err(dev, "Failed to set display off: %d\n", ret);
		return ret;
	}
	msleep(50);

	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
	if (ret < 0) {
		dev_err(dev, "Failed to enter sleep mode: %d\n", ret);
		return ret;
	}
	msleep(150);

(I'm mainly referring to the mipi_dsi_dcs_*() here instead of the
 magic numbers...)

quoted hunk

+}
+
+static int nt35521_prepare(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (nt->prepared)
+		return 0;
+
+	gpiod_set_value_cansleep(nt->pwrp5_gpio, 1);
+	usleep_range(1000, 1500);
+	gpiod_set_value_cansleep(nt->pwrn5_gpio, 1);
+	usleep_range(10000, 15000);
+	gpiod_set_value_cansleep(nt->rst_gpio, 0);
+	msleep(150);
+
+	nt35521_panel_on(nt);
+
+	nt->prepared = true;
+
+	return 0;
+}
+
+static int nt35521_unprepare(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (!nt->prepared)
+		return 0;
+
+	nt35521_panel_off(nt);
+
+	gpiod_set_value_cansleep(nt->rst_gpio, 1);
+
+	nt->prepared = false;
+
+	return 0;
+}
+
+static int nt35521_enable(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (nt->enabled)
+		return 0;
+
+	gpiod_set_value_cansleep(nt->en_gpio, 1);
+
+	nt->enabled = true;
+
+	return 0;
+}
+
+static int nt35521_disable(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (!nt->enabled)
+		return 0;
+
+	gpiod_set_value_cansleep(nt->en_gpio, 0);
+
+	nt->enabled = false;
+
+	return 0;
+}
+
+static const struct drm_display_mode nt35521_modes = {
+	.clock = 133306,
+	.hdisplay = 720,
+	.hsync_start = 720 + 632,
+	.hsync_end = 720 + 632 + 40,
+	.htotal = 720 + 632 + 40 + 295,
+	.vdisplay = 1280,
+	.vsync_start = 1280 + 18,
+	.vsync_end = 1280 + 18 + 1,
+	.vtotal = 1280 + 18 + 1 + 18,
+};
+
+static int nt35521_get_modes(struct drm_panel *panel,
+			      struct drm_connector *connector)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+	struct drm_display_mode *mode;
+
+	mode = drm_mode_duplicate(connector->dev, &nt35521_modes);
+	if (!mode) {
+		DRM_DEV_ERROR(nt->dev, "failed to add display mode\n");
+		return -ENOMEM;
+	}
+
+	drm_mode_set_name(mode);
+	drm_mode_probed_add(connector, mode);
+
+	connector->display_info.width_mm = 65;
+	connector->display_info.height_mm = 116;
+
+	return 1;
+}
+
+static const struct drm_panel_funcs nt35521_drm_funcs = {
+	.prepare = nt35521_prepare,
+	.unprepare = nt35521_unprepare,
+	.enable = nt35521_enable,
+	.disable = nt35521_disable,
+	.get_modes = nt35521_get_modes,
+};
+
+static int nt35521_backlight_update_status(struct backlight_device *bd)
+{
+	struct nt35521_panel *nt = bl_get_data(bd);
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
+	u8 brightness = bd->props.brightness;

	u8 brightness = backlight_get_brightness(bl);

Is preferred now I think(?).

quoted hunk

+	int ret;
+
+	ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
+				 &brightness,
+				 sizeof(brightness));

Does this work too?

	ret = mipi_dsi_dcs_set_display_brightness(dsi, brightness);

quoted hunk

+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static const struct backlight_ops nt35521_backlight_ops = {
+	.update_status = nt35521_backlight_update_status,
+};
+
+static int nt35521_probe(struct mipi_dsi_device *dsi)
+{
+	struct backlight_properties props;
+	struct device *dev = &dsi->dev;
+	struct nt35521_panel *nt;
+	int ret;
+
+	nt = devm_kzalloc(dev, sizeof(*nt), GFP_KERNEL);
+	if (!nt)
+		return -ENOMEM;
+
+	nt->rst_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->rst_gpio)) {
+		ret = PTR_ERR(nt->rst_gpio);
+		DRM_DEV_ERROR(dev, "failed to get reset GPIO: %d\n", ret);
+		return ret;
+	}
+
+	nt->pwrp5_gpio = devm_gpiod_get(dev, "pwr-positive5", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->pwrp5_gpio)) {
+		ret = PTR_ERR(nt->pwrp5_gpio);
+		DRM_DEV_ERROR(dev, "failed to get positive5 GPIO: %d\n", ret);
+		return ret;
+	}
+
+	nt->pwrn5_gpio = devm_gpiod_get(dev, "pwr-negative5", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->pwrn5_gpio)) {
+		ret = PTR_ERR(nt->pwrn5_gpio);
+		DRM_DEV_ERROR(dev, "failed to get negative5 GPIO: %d\n", ret);
+		return ret;
+	}
+

These two GPIOs look a lot like typical 5V display regulators that would
be better described through the regulator subsystem. You can declare
them as fixed-regulator to toggle the GPIO.

quoted hunk

+	nt->en_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->en_gpio)) {
+		ret = PTR_ERR(nt->en_gpio);
+		DRM_DEV_ERROR(dev, "failed to get enable GPIO: %d\n", ret);
+		return ret;
+	}

Does this refer to the "platform-bklight-en-gpio" in the Sony sources?
Perhaps calling it "backlight-gpios" or something like that would be
more clear to show that it's related to the backlight.

Thanks!
Stephan

Re: [PATCH 2/2] drm/panel: Add Truly NT35521 panel driver

From: Shawn Guo <hidden>
Date: 2021-08-08 13:45:08

Hi Stephan,

Thanks for looking at the patch!

On Wed, Aug 04, 2021 at 02:09:19PM +0200, Stephan Gerhold wrote:

Hi Shawn,

Thanks for the patch!

On Wed, Aug 04, 2021 at 04:13:52PM +0800, Shawn Guo wrote:

quoted

It adds a drm driver for Truly NT35521 5.24" 1280x720 DSI panel, which
can be found on Sony Xperia M4 Aqua phone.  The panel backlight is
managed through DSI link.

Signed-off-by: Shawn Guo <redacted>
---
 drivers/gpu/drm/panel/Kconfig               |   9 +
 drivers/gpu/drm/panel/Makefile              |   1 +
 drivers/gpu/drm/panel/panel-truly-nt35521.c | 491 ++++++++++++++++++++
 3 files changed, 501 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-truly-nt35521.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index ef87d92cdf49..cdc4abd5c40c 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig

@@ -537,6 +537,15 @@ config DRM_PANEL_TPO_TPG110
 	  400CH LTPS TFT LCD Single Chip Digital Driver for up to
 	  800x400 LCD panels.
 
+config DRM_PANEL_TRULY_NT35521
+	tristate "Truly NT35521 panel"

I think the name "Truly NT35521" is a bit too generic. AFAIK "Truly" is
a panel vendor and the NovaTek NT35521 is the panel controller. But
there are almost certainly other Truly panels that were also combined
with a NT35521 but need a slightly different configuration.

If you don't know more than "Truly NT35521" based on the Sony sources,
maybe do it similar to "asus,z00t-tm5p5-n35596" and use a compatible
like "sony,<device>-truly-nt35521". Would be good to clarify the Kconfig
option here too.

Sounds good!

quoted

+	depends on OF
+	depends on DRM_MIPI_DSI
+	depends on BACKLIGHT_CLASS_DEVICE
+	help
+	  Say Y here if you want to enable support for Truly NT35521
+	  1280x720 DSI panel.
+
 config DRM_PANEL_TRULY_NT35597_WQXGA
 	tristate "Truly WQXGA"
 	depends on OF

diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index cae4d976c069..3d3c98cb7a7b 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile

@@ -56,6 +56,7 @@ obj-$(CONFIG_DRM_PANEL_TDO_TL070WSH30) += panel-tdo-tl070wsh30.o
 obj-$(CONFIG_DRM_PANEL_TPO_TD028TTEC1) += panel-tpo-td028ttec1.o
 obj-$(CONFIG_DRM_PANEL_TPO_TD043MTEA1) += panel-tpo-td043mtea1.o
 obj-$(CONFIG_DRM_PANEL_TPO_TPG110) += panel-tpo-tpg110.o
+obj-$(CONFIG_DRM_PANEL_TRULY_NT35521) += panel-truly-nt35521.o
 obj-$(CONFIG_DRM_PANEL_TRULY_NT35597_WQXGA) += panel-truly-nt35597.o
 obj-$(CONFIG_DRM_PANEL_VISIONOX_RM69299) += panel-visionox-rm69299.o
 obj-$(CONFIG_DRM_PANEL_XINPENG_XPP055C272) += panel-xinpeng-xpp055c272.o

diff --git a/drivers/gpu/drm/panel/panel-truly-nt35521.c b/drivers/gpu/drm/panel/panel-truly-nt35521.c
new file mode 100644
index 000000000000..ea3cfb46be7e
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-truly-nt35521.c

@@ -0,0 +1,491 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2021, Linaro Limited
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+
+#include <video/mipi_display.h>
+
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_print.h>
+
+struct nt35521_panel {
+	struct drm_panel panel;
+	struct device *dev;
+	struct gpio_desc *rst_gpio;
+	struct gpio_desc *pwrp5_gpio;
+	struct gpio_desc *pwrn5_gpio;
+	struct gpio_desc *en_gpio;
+	bool prepared;
+	bool enabled;
+};
+
+static inline struct nt35521_panel *panel_to_nt35521(struct drm_panel *panel)
+{
+	return container_of(panel, struct nt35521_panel, panel);
+}
+
+#define nt_dcs_write(seq...)						\
+({									\
+	const u8 d[] = { seq };						\
+	if (mipi_dsi_dcs_write_buffer(dsi, d, ARRAY_SIZE(d)) < 0)	\
+		DRM_DEV_ERROR(dev, "dcs write buffer failed\n");	\
+})
+
+#define nt_gen_write(seq...)						\
+({									\
+	const u8 d[] = { seq };						\
+	if (mipi_dsi_generic_write(dsi, d, ARRAY_SIZE(d)) < 0)		\
+		DRM_DEV_ERROR(dev, "generic write buffer failed\n");	\
+})
+
+static void nt35521_panel_on(struct nt35521_panel *nt)
+{
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
+	struct device *dev = nt->dev;
+
+	/* Transmit data in low power mode */
+	dsi->mode_flags |= MIPI_DSI_MODE_LPM;
+
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	nt_dcs_write(0xff, 0xaa, 0x55, 0xa5, 0x80);
+	nt_dcs_write(0x6f, 0x11, 0x00);
+	nt_dcs_write(0xf7, 0x20, 0x00);
+	nt_dcs_write(0x6f, 0x01);
+	nt_dcs_write(0xb1, 0x21);
+	nt_dcs_write(0xbd, 0x01, 0xa0, 0x10, 0x08, 0x01);
+	nt_dcs_write(0xb8, 0x01, 0x02, 0x0c, 0x02);
+	nt_dcs_write(0xbb, 0x11, 0x11);
+	nt_dcs_write(0xbc, 0x00, 0x00);
+	nt_dcs_write(0xb6, 0x02);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x01);
+	nt_dcs_write(0xb0, 0x09, 0x09);
+	nt_dcs_write(0xb1, 0x09, 0x09);
+	nt_dcs_write(0xbc, 0x8c, 0x00);
+	nt_dcs_write(0xbd, 0x8c, 0x00);
+	nt_dcs_write(0xca, 0x00);
+	nt_dcs_write(0xc0, 0x04);
+	nt_dcs_write(0xbe, 0xb5);
+	nt_dcs_write(0xb3, 0x35, 0x35);
+	nt_dcs_write(0xb4, 0x25, 0x25);
+	nt_dcs_write(0xb9, 0x43, 0x43);
+	nt_dcs_write(0xba, 0x24, 0x24);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x02);
+	nt_dcs_write(0xee, 0x03);
+	nt_dcs_write(0xb0, 0x00, 0xb2, 0x00, 0xb3, 0x00, 0xb6, 0x00,
+		     0xc3, 0x00, 0xce, 0x00, 0xe1, 0x00, 0xf3, 0x01,
+		     0x11);
+	nt_dcs_write(0xb1, 0x01, 0x2e, 0x01, 0x5c, 0x01, 0x82, 0x01,
+		     0xc3, 0x01, 0xfe, 0x02, 0x00, 0x02, 0x37, 0x02,
+		     0x77);
+	nt_dcs_write(0xb2, 0x02, 0xa1, 0x02, 0xd7, 0x02, 0xfe, 0x03,
+		     0x2c, 0x03, 0x4b, 0x03, 0x63, 0x03, 0x8f, 0x03,
+		     0x90);
+	nt_dcs_write(0xb3, 0x03, 0x96, 0x03, 0x98);
+	nt_dcs_write(0xb4, 0x00, 0x81, 0x00, 0x8b, 0x00, 0x9c, 0x00,
+		     0xa9, 0x00, 0xb5, 0x00, 0xcb, 0x00, 0xdf, 0x01,
+		     0x02);
+	nt_dcs_write(0xb5, 0x01, 0x1f, 0x01, 0x51, 0x01, 0x7a, 0x01,
+		     0xbf, 0x01, 0xfa, 0x01, 0xfc, 0x02, 0x34, 0x02, 0x76);
+	nt_dcs_write(0xb6, 0x02, 0x9f, 0x02, 0xd7, 0x02, 0xfc, 0x03, 0x2c,
+		     0x03, 0x4a, 0x03, 0x63, 0x03, 0x8f, 0x03, 0xa2);
+	nt_dcs_write(0xb7, 0x03, 0xb8, 0x03, 0xba);
+	nt_dcs_write(0xb8, 0x00, 0x01, 0x00, 0x02, 0x00, 0x0e, 0x00, 0x2a,
+		     0x00, 0x41, 0x00, 0x67, 0x00, 0x87, 0x00, 0xb9);
+	nt_dcs_write(0xb9, 0x00, 0xe2, 0x01, 0x22, 0x01, 0x54, 0x01, 0xa3,
+		     0x01, 0xe6, 0x01, 0xe7, 0x02, 0x24, 0x02, 0x67);
+	nt_dcs_write(0xba, 0x02, 0x93, 0x02, 0xcd, 0x02, 0xf6, 0x03, 0x31,
+		     0x03, 0x6c, 0x03, 0xe9, 0x03, 0xef, 0x03, 0xf4);
+	nt_dcs_write(0xbb, 0x03, 0xf6, 0x03, 0xf7);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x03);
+	nt_dcs_write(0xb0, 0x22, 0x00);
+	nt_dcs_write(0xb1, 0x22, 0x00);
+	nt_dcs_write(0xb2, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xb3, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xb4, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xb5, 0x05, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xba, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xbb, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xbc, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xbd, 0x53, 0x00, 0x60, 0x00, 0x00);
+	nt_dcs_write(0xc0, 0x00, 0x34, 0x00, 0x00);
+	nt_dcs_write(0xc1, 0x00, 0x00, 0x34, 0x00);
+	nt_dcs_write(0xc2, 0x00, 0x00, 0x34, 0x00);
+	nt_dcs_write(0xc3, 0x00, 0x00, 0x34, 0x00);
+	nt_dcs_write(0xc4, 0x60);
+	nt_dcs_write(0xc5, 0xc0);
+	nt_dcs_write(0xc6, 0x00);
+	nt_dcs_write(0xc7, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x05);
+	nt_dcs_write(0xb0, 0x17, 0x06);
+	nt_dcs_write(0xb1, 0x17, 0x06);
+	nt_dcs_write(0xb2, 0x17, 0x06);
+	nt_dcs_write(0xb3, 0x17, 0x06);
+	nt_dcs_write(0xb4, 0x17, 0x06);
+	nt_dcs_write(0xb5, 0x17, 0x06);
+	nt_dcs_write(0xb6, 0x17, 0x06);
+	nt_dcs_write(0xb7, 0x17, 0x06);
+	nt_dcs_write(0xb8, 0x00);
+	nt_dcs_write(0xb9, 0x00, 0x03);
+	nt_dcs_write(0xba, 0x00, 0x00);
+	nt_dcs_write(0xbb, 0x02, 0x03);
+	nt_dcs_write(0xbc, 0x02, 0x03);
+	nt_dcs_write(0xbd, 0x03, 0x03, 0x00, 0x03, 0x03);
+	nt_dcs_write(0xc0, 0x0b);
+	nt_dcs_write(0xc1, 0x09);
+	nt_dcs_write(0xc2, 0xa6);
+	nt_dcs_write(0xc3, 0x05);
+	nt_dcs_write(0xc4, 0x00);
+	nt_dcs_write(0xc5, 0x02);
+	nt_dcs_write(0xc6, 0x22);
+	nt_dcs_write(0xc7, 0x03);
+	nt_dcs_write(0xc8, 0x07, 0x20);
+	nt_dcs_write(0xc9, 0x03, 0x20);
+	nt_dcs_write(0xca, 0x01, 0x60);
+	nt_dcs_write(0xcb, 0x01, 0x60);
+	nt_dcs_write(0xcc, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xcd, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xce, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xcf, 0x00, 0x00, 0x02);
+	nt_dcs_write(0xd1, 0x00, 0x05, 0x01, 0x07, 0x10);
+	nt_dcs_write(0xd2, 0x10, 0x05, 0x05, 0x03, 0x10);
+	nt_dcs_write(0xd3, 0x20, 0x00, 0x43, 0x07, 0x10);
+	nt_dcs_write(0xd4, 0x30, 0x00, 0x43, 0x07, 0x10);
+	nt_dcs_write(0xd0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd5, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		     0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd6, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		     0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd7, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+		     0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd8, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xe5, 0x06);
+	nt_dcs_write(0xe6, 0x06);
+	nt_dcs_write(0xe7, 0x00);
+	nt_dcs_write(0xe8, 0x06);
+	nt_dcs_write(0xe9, 0x06);
+	nt_dcs_write(0xea, 0x06);
+	nt_dcs_write(0xeb, 0x00);
+	nt_dcs_write(0xec, 0x00);
+	nt_dcs_write(0xed, 0x30);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x06);
+	nt_dcs_write(0xb0, 0x31, 0x31);
+	nt_dcs_write(0xb1, 0x31, 0x31);
+	nt_dcs_write(0xb2, 0x2d, 0x2e);
+	nt_dcs_write(0xb3, 0x31, 0x34);
+	nt_dcs_write(0xb4, 0x29, 0x2a);
+	nt_dcs_write(0xb5, 0x12, 0x10);
+	nt_dcs_write(0xb6, 0x18, 0x16);
+	nt_dcs_write(0xb7, 0x00, 0x02);
+	nt_dcs_write(0xb8, 0x08, 0x31);
+	nt_dcs_write(0xb9, 0x31, 0x31);
+	nt_dcs_write(0xba, 0x31, 0x31);
+	nt_dcs_write(0xbb, 0x31, 0x08);
+	nt_dcs_write(0xbc, 0x03, 0x01);
+	nt_dcs_write(0xbd, 0x17, 0x19);
+	nt_dcs_write(0xbe, 0x11, 0x13);
+	nt_dcs_write(0xbf, 0x2a, 0x29);
+	nt_dcs_write(0xc0, 0x34, 0x31);
+	nt_dcs_write(0xc1, 0x2e, 0x2d);
+	nt_dcs_write(0xc2, 0x31, 0x31);
+	nt_dcs_write(0xc3, 0x31, 0x31);
+	nt_dcs_write(0xc4, 0x31, 0x31);
+	nt_dcs_write(0xc5, 0x31, 0x31);
+	nt_dcs_write(0xc6, 0x2e, 0x2d);
+	nt_dcs_write(0xc7, 0x31, 0x34);
+	nt_dcs_write(0xc8, 0x29, 0x2a);
+	nt_dcs_write(0xc9, 0x17, 0x19);
+	nt_dcs_write(0xca, 0x11, 0x13);
+	nt_dcs_write(0xcb, 0x03, 0x01);
+	nt_dcs_write(0xcc, 0x08, 0x31);
+	nt_dcs_write(0xcd, 0x31, 0x31);
+	nt_dcs_write(0xce, 0x31, 0x31);
+	nt_dcs_write(0xcf, 0x31, 0x08);
+	nt_dcs_write(0xd0, 0x00, 0x02);
+	nt_dcs_write(0xd1, 0x12, 0x10);
+	nt_dcs_write(0xd2, 0x18, 0x16);
+	nt_dcs_write(0xd3, 0x2a, 0x29);
+	nt_dcs_write(0xd4, 0x34, 0x31);
+	nt_dcs_write(0xd5, 0x2d, 0x2e);
+	nt_dcs_write(0xd6, 0x31, 0x31);
+	nt_dcs_write(0xd7, 0x31, 0x31);
+	nt_dcs_write(0xe5, 0x31, 0x31);
+	nt_dcs_write(0xe6, 0x31, 0x31);
+	nt_dcs_write(0xd8, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xd9, 0x00, 0x00, 0x00, 0x00, 0x00);
+	nt_dcs_write(0xe7, 0x00);
+	nt_dcs_write(0x6f, 0x02);
+	nt_dcs_write(0xf7, 0x47);
+	nt_dcs_write(0x6f, 0x0a);
+	nt_dcs_write(0xf7, 0x02);
+	nt_dcs_write(0x6f, 0x17);
+	nt_dcs_write(0xf4, 0x60);
+	nt_dcs_write(0x6f, 0x01);
+	nt_dcs_write(0xf9, 0x46);
+	nt_dcs_write(0x6f, 0x11);
+	nt_dcs_write(0xf3, 0x01);
+	nt_dcs_write(0x35, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	nt_dcs_write(0xd9, 0x02, 0x03, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x00, 0x00);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x08, 0x00);
+	nt_dcs_write(0xb1, 0x6c, 0x21);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x00, 0x00);
+	nt_dcs_write(0x35, 0x00);
+	nt_gen_write(0x11, 0x00);
+	msleep(120);
+	nt_gen_write(0x29, 0x00);
+	usleep_range(1000, 1500);
+	nt_dcs_write(0x53, 0x24);

Did you mix up "nt_dcs_write" and "nt_gen_write" here?
The nt_gen_write(0x11, 0x00); looks like MIPI_DCS_EXIT_SLEEP_MODE
and the nt_gen_write(0x29, 0x00); looks like MIPI_DCS_SET_DISPLAY_ON.

For reference you can pull your original reference DTB from Sony through
my panel driver generator: https://github.com/msm8916-mainline/linux-mdss-dsi-panel-driver-generator

Wow, very nice!  It really deserves wider spread!

It produces the following (I compiled "msm8939-kanuti_tulip.dtb"
from https://github.com/sonyxperiadev/kernel/tree/aosp/LA.BR.1.3.3_rb2.14,
not sure if that is right):

	// ...
	dsi_generic_write_seq(dsi, 0x35, 0x00);

	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
	if (ret < 0) {
		dev_err(dev, "Failed to exit sleep mode: %d\n", ret);
		return ret;
	}
	msleep(120);

	ret = mipi_dsi_dcs_set_display_on(dsi);
	if (ret < 0) {
		dev_err(dev, "Failed to set display on: %d\n", ret);
		return ret;
	}
	usleep_range(1000, 2000);

	dsi_generic_write_seq(dsi, 0x53, 0x24);

Which also suggests that generic and DCS writes are mixed up here.

Note however that you could not use the generated driver as-is,
because Sony seems to use their own display driver instead of Qualcomm's
and some things seem to be different.

I re-created the driver using your generator.  With modeling the 5v
control GPIOs with regulators and adding backlight-gpios support, the
driver works quite nicely, except the following two problems:

1) I have to drop the MIPI_DSI_MODE_LPM configuration from .update_status
   hook. Otherwise brightness did not get updated to panel.

---8<------

diff --git a/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c b/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c
index 31e5f942a039..eba926c6f722 100644
--- a/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c
+++ b/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c

@@ -420,33 +420,23 @@ static int truly_nt35521_bl_update_status(struct backlight_device *bl)
        u16 brightness = backlight_get_brightness(bl);
        int ret;
 
-       dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
-
        ret = mipi_dsi_dcs_set_display_brightness(dsi, brightness);
        if (ret < 0)
                return ret;
 
-       dsi->mode_flags |= MIPI_DSI_MODE_LPM;
-
        return 0;
 }
------>8---

2) The driver works good, if the kernel is launched via "fastboot boot".
   But if the kernel is flashed to eMMC and launched by bootloader with
   splash screen, kernel will fail to bring up the panel.  After kernel
   boots up, a blank & unblank cycle can get panel work though.

The problem 2) is not driver generator related.  @Konrad, did you see
it on asus-z00t-tm5p5-n35596 driver?

Shawn

quoted

+}
+
+static void nt35521_panel_off(struct nt35521_panel *nt)
+{
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
+	struct device *dev = nt->dev;
+
+	/* Transmit data in high speed mode */
+	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
+
+	nt_dcs_write(0x28, 0x00);
+	msleep(50);
+	nt_dcs_write(0x10, 0x00);
+	msleep(150);

A bit more deobfuscated from the panel driver generator:

	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;

	ret = mipi_dsi_dcs_set_display_off(dsi);
	if (ret < 0) {
		dev_err(dev, "Failed to set display off: %d\n", ret);
		return ret;
	}
	msleep(50);

	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
	if (ret < 0) {
		dev_err(dev, "Failed to enter sleep mode: %d\n", ret);
		return ret;
	}
	msleep(150);

(I'm mainly referring to the mipi_dsi_dcs_*() here instead of the
 magic numbers...)

quoted

+}
+
+static int nt35521_prepare(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (nt->prepared)
+		return 0;
+
+	gpiod_set_value_cansleep(nt->pwrp5_gpio, 1);
+	usleep_range(1000, 1500);
+	gpiod_set_value_cansleep(nt->pwrn5_gpio, 1);
+	usleep_range(10000, 15000);
+	gpiod_set_value_cansleep(nt->rst_gpio, 0);
+	msleep(150);
+
+	nt35521_panel_on(nt);
+
+	nt->prepared = true;
+
+	return 0;
+}
+
+static int nt35521_unprepare(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (!nt->prepared)
+		return 0;
+
+	nt35521_panel_off(nt);
+
+	gpiod_set_value_cansleep(nt->rst_gpio, 1);
+
+	nt->prepared = false;
+
+	return 0;
+}
+
+static int nt35521_enable(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (nt->enabled)
+		return 0;
+
+	gpiod_set_value_cansleep(nt->en_gpio, 1);
+
+	nt->enabled = true;
+
+	return 0;
+}
+
+static int nt35521_disable(struct drm_panel *panel)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+
+	if (!nt->enabled)
+		return 0;
+
+	gpiod_set_value_cansleep(nt->en_gpio, 0);
+
+	nt->enabled = false;
+
+	return 0;
+}
+
+static const struct drm_display_mode nt35521_modes = {
+	.clock = 133306,
+	.hdisplay = 720,
+	.hsync_start = 720 + 632,
+	.hsync_end = 720 + 632 + 40,
+	.htotal = 720 + 632 + 40 + 295,
+	.vdisplay = 1280,
+	.vsync_start = 1280 + 18,
+	.vsync_end = 1280 + 18 + 1,
+	.vtotal = 1280 + 18 + 1 + 18,
+};
+
+static int nt35521_get_modes(struct drm_panel *panel,
+			      struct drm_connector *connector)
+{
+	struct nt35521_panel *nt = panel_to_nt35521(panel);
+	struct drm_display_mode *mode;
+
+	mode = drm_mode_duplicate(connector->dev, &nt35521_modes);
+	if (!mode) {
+		DRM_DEV_ERROR(nt->dev, "failed to add display mode\n");
+		return -ENOMEM;
+	}
+
+	drm_mode_set_name(mode);
+	drm_mode_probed_add(connector, mode);
+
+	connector->display_info.width_mm = 65;
+	connector->display_info.height_mm = 116;
+
+	return 1;
+}
+
+static const struct drm_panel_funcs nt35521_drm_funcs = {
+	.prepare = nt35521_prepare,
+	.unprepare = nt35521_unprepare,
+	.enable = nt35521_enable,
+	.disable = nt35521_disable,
+	.get_modes = nt35521_get_modes,
+};
+
+static int nt35521_backlight_update_status(struct backlight_device *bd)
+{
+	struct nt35521_panel *nt = bl_get_data(bd);
+	struct mipi_dsi_device *dsi = to_mipi_dsi_device(nt->dev);
+	u8 brightness = bd->props.brightness;

	u8 brightness = backlight_get_brightness(bl);

Is preferred now I think(?).

quoted

+	int ret;
+
+	ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
+				 &brightness,
+				 sizeof(brightness));

Does this work too?

	ret = mipi_dsi_dcs_set_display_brightness(dsi, brightness);

quoted

+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static const struct backlight_ops nt35521_backlight_ops = {
+	.update_status = nt35521_backlight_update_status,
+};
+
+static int nt35521_probe(struct mipi_dsi_device *dsi)
+{
+	struct backlight_properties props;
+	struct device *dev = &dsi->dev;
+	struct nt35521_panel *nt;
+	int ret;
+
+	nt = devm_kzalloc(dev, sizeof(*nt), GFP_KERNEL);
+	if (!nt)
+		return -ENOMEM;
+
+	nt->rst_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->rst_gpio)) {
+		ret = PTR_ERR(nt->rst_gpio);
+		DRM_DEV_ERROR(dev, "failed to get reset GPIO: %d\n", ret);
+		return ret;
+	}
+
+	nt->pwrp5_gpio = devm_gpiod_get(dev, "pwr-positive5", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->pwrp5_gpio)) {
+		ret = PTR_ERR(nt->pwrp5_gpio);
+		DRM_DEV_ERROR(dev, "failed to get positive5 GPIO: %d\n", ret);
+		return ret;
+	}
+
+	nt->pwrn5_gpio = devm_gpiod_get(dev, "pwr-negative5", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->pwrn5_gpio)) {
+		ret = PTR_ERR(nt->pwrn5_gpio);
+		DRM_DEV_ERROR(dev, "failed to get negative5 GPIO: %d\n", ret);
+		return ret;
+	}
+

These two GPIOs look a lot like typical 5V display regulators that would
be better described through the regulator subsystem. You can declare
them as fixed-regulator to toggle the GPIO.

quoted

+	nt->en_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
+	if (IS_ERR(nt->en_gpio)) {
+		ret = PTR_ERR(nt->en_gpio);
+		DRM_DEV_ERROR(dev, "failed to get enable GPIO: %d\n", ret);
+		return ret;
+	}

Does this refer to the "platform-bklight-en-gpio" in the Sony sources?
Perhaps calling it "backlight-gpios" or something like that would be
more clear to show that it's related to the backlight.

Thanks!
Stephan

Re: [PATCH 2/2] drm/panel: Add Truly NT35521 panel driver

From: Stephan Gerhold <stephan@gerhold.net>
Date: 2021-08-08 15:29:43

On Sun, Aug 08, 2021 at 09:44:57PM +0800, Shawn Guo wrote:

quoted hunk

On Wed, Aug 04, 2021 at 02:09:19PM +0200, Stephan Gerhold wrote:

quoted

On Wed, Aug 04, 2021 at 04:13:52PM +0800, Shawn Guo wrote:

quoted

+ ...
+	nt_dcs_write(0xb1, 0x6c, 0x21);
+	nt_dcs_write(0xf0, 0x55, 0xaa, 0x52, 0x00, 0x00);
+	nt_dcs_write(0x35, 0x00);
+	nt_gen_write(0x11, 0x00);
+	msleep(120);
+	nt_gen_write(0x29, 0x00);
+	usleep_range(1000, 1500);
+	nt_dcs_write(0x53, 0x24);

Did you mix up "nt_dcs_write" and "nt_gen_write" here?
The nt_gen_write(0x11, 0x00); looks like MIPI_DCS_EXIT_SLEEP_MODE
and the nt_gen_write(0x29, 0x00); looks like MIPI_DCS_SET_DISPLAY_ON.

For reference you can pull your original reference DTB from Sony through
my panel driver generator: https://github.com/msm8916-mainline/linux-mdss-dsi-panel-driver-generator

Wow, very nice!  It really deserves wider spread!

quoted

It produces the following (I compiled "msm8939-kanuti_tulip.dtb"
from https://github.com/sonyxperiadev/kernel/tree/aosp/LA.BR.1.3.3_rb2.14,
not sure if that is right):

	// ...
	dsi_generic_write_seq(dsi, 0x35, 0x00);

	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
	if (ret < 0) {
		dev_err(dev, "Failed to exit sleep mode: %d\n", ret);
		return ret;
	}
	msleep(120);

	ret = mipi_dsi_dcs_set_display_on(dsi);
	if (ret < 0) {
		dev_err(dev, "Failed to set display on: %d\n", ret);
		return ret;
	}
	usleep_range(1000, 2000);

	dsi_generic_write_seq(dsi, 0x53, 0x24);

Which also suggests that generic and DCS writes are mixed up here.

Note however that you could not use the generated driver as-is,
because Sony seems to use their own display driver instead of Qualcomm's
and some things seem to be different.

I re-created the driver using your generator.  With modeling the 5v
control GPIOs with regulators and adding backlight-gpios support, the
driver works quite nicely, except the following two problems:

1) I have to drop the MIPI_DSI_MODE_LPM configuration from .update_status
   hook. Otherwise brightness did not get updated to panel.

---8<------

diff --git a/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c b/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c
index 31e5f942a039..eba926c6f722 100644
--- a/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c
+++ b/drivers/gpu/drm/panel/panel-sony-tulip-truly-nt35521.c

@@ -420,33 +420,23 @@ static int truly_nt35521_bl_update_status(struct backlight_device *bl)
        u16 brightness = backlight_get_brightness(bl);
        int ret;
 
-       dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
-
        ret = mipi_dsi_dcs_set_display_brightness(dsi, brightness);
        if (ret < 0)
                return ret;
 
-       dsi->mode_flags |= MIPI_DSI_MODE_LPM;
-
        return 0;
 }
------>8---

I have to admit I don't know much about Low Power Mode vs High Speed
Mode. As long it works it is good I guess :-)

2) The driver works good, if the kernel is launched via "fastboot boot".
   But if the kernel is flashed to eMMC and launched by bootloader with
   splash screen, kernel will fail to bring up the panel.  After kernel
   boots up, a blank & unblank cycle can get panel work though.

The problem 2) is not driver generator related.  @Konrad, did you see
it on asus-z00t-tm5p5-n35596 driver?

Do you have CONFIG_DRM_MSM=y (built-in) instead of =m (module) maybe?
I think a similar issue exists on MSM8916 but it does not happen
for some reason if CONFIG_DRM_MSM=m instead of =y. Somehow having it
load later during the boot process fixes some things there.

Thanks,
Stephan

Re: [PATCH 2/2] drm/panel: Add Truly NT35521 panel driver

From: Shawn Guo <hidden>
Date: 2021-08-09 04:20:29

On Sun, Aug 08, 2021 at 05:29:30PM +0200, Stephan Gerhold wrote:

quoted

2) The driver works good, if the kernel is launched via "fastboot boot".
   But if the kernel is flashed to eMMC and launched by bootloader with
   splash screen, kernel will fail to bring up the panel.  After kernel
   boots up, a blank & unblank cycle can get panel work though.

The problem 2) is not driver generator related.  @Konrad, did you see
it on asus-z00t-tm5p5-n35596 driver?

Do you have CONFIG_DRM_MSM=y (built-in) instead of =m (module) maybe?
I think a similar issue exists on MSM8916 but it does not happen
for some reason if CONFIG_DRM_MSM=m instead of =y. Somehow having it
load later during the boot process fixes some things there.

Indeed!  I have CONFIG_DRM_MSM=y in my build, and changing it to module
removes the problem.  Thanks much for the hint, Stephan!

Shawn

Re: [PATCH 1/2] dt-bindings: display: panel: Add Truly NT35521 panel support

From: Rob Herring <robh@kernel.org>
Date: 2021-08-11 18:52:03

On Wed, Aug 04, 2021 at 04:13:51PM +0800, Shawn Guo wrote:

quoted hunk

The Truly NT35521 is a 5.24" 1280x720 DSI panel, and the backlight is
managed through DSI link.

Signed-off-by: Shawn Guo <redacted>
---
 .../bindings/display/panel/truly,nt35521.yaml | 62 +++++++++++++++++++
 1 file changed, 62 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml

diff --git a/Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml b/Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml
new file mode 100644
index 000000000000..4727c3df6eb8
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml

@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/truly,nt35521.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Truly NT35521 5.24" 1280x720 MIPI-DSI Panel
+
+maintainers:
+  - Shawn Guo <shawn.guo@linaro.org>
+
+description: |
+  The Truly NT35521 is a 5.24" 1280x720 MIPI-DSI panel.  The panel backlight
+  is managed through DSI link.
+
+allOf:
+  - $ref: panel-common.yaml#
+
+properties:
+  compatible:
+    const: truly,nt35521
+
+  reg: true
+
+  reset-gpios: true
+
+  enable-gpios: true
+
+  pwr-positive5-gpios:
+    maxItems: 1
+
+  pwr-negative5-gpios:
+    maxItems: 1

Are these +/-5V supplies? If so, they should be modeled with 
gpio-regulator perhaps unless the panel connection could only ever be 
GPIOs.

+
+required:
+  - compatible
+  - reg
+  - reset-gpios
+  - enable-gpios
+  - pwr-positive5-gpios
+  - pwr-negative5-gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    dsi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        panel@0 {
+            compatible = "truly,nt35521";
+            reg = <0>;
+            reset-gpios = <&msmgpio 25 GPIO_ACTIVE_LOW>;
+            pwr-positive5-gpios = <&msmgpio 114 GPIO_ACTIVE_HIGH>;
+            pwr-negative5-gpios = <&msmgpio 17 GPIO_ACTIVE_HIGH>;
+            enable-gpios = <&msmgpio 10 GPIO_ACTIVE_HIGH>;
+        };
+    };
+...
-- 
2.17.1

Re: [PATCH 1/2] dt-bindings: display: panel: Add Truly NT35521 panel support

From: Shawn Guo <hidden>
Date: 2021-08-13 13:59:53

On Wed, Aug 11, 2021 at 12:51:56PM -0600, Rob Herring wrote:

On Wed, Aug 04, 2021 at 04:13:51PM +0800, Shawn Guo wrote:

quoted

The Truly NT35521 is a 5.24" 1280x720 DSI panel, and the backlight is
managed through DSI link.

Signed-off-by: Shawn Guo <redacted>
---
 .../bindings/display/panel/truly,nt35521.yaml | 62 +++++++++++++++++++
 1 file changed, 62 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml

diff --git a/Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml b/Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml
new file mode 100644
index 000000000000..4727c3df6eb8
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/panel/truly,nt35521.yaml

@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/truly,nt35521.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Truly NT35521 5.24" 1280x720 MIPI-DSI Panel
+
+maintainers:
+  - Shawn Guo <shawn.guo@linaro.org>
+
+description: |
+  The Truly NT35521 is a 5.24" 1280x720 MIPI-DSI panel.  The panel backlight
+  is managed through DSI link.
+
+allOf:
+  - $ref: panel-common.yaml#
+
+properties:
+  compatible:
+    const: truly,nt35521
+
+  reg: true
+
+  reset-gpios: true
+
+  enable-gpios: true
+
+  pwr-positive5-gpios:
+    maxItems: 1
+
+  pwr-negative5-gpios:
+    maxItems: 1

Are these +/-5V supplies? If so, they should be modeled with 
gpio-regulator perhaps unless the panel connection could only ever be 
GPIOs.

Hi Rob,

The binding has been updated in v2 [1].  Please help review that.
Thanks!

Shawn

[1] https://lore.kernel.org/linux-arm-msm/20210809051008.6172-2-shawn.guo@linaro.org/T/#m587035a602b1be6c5326dcf24af01b3e8a5d2cc9

quoted

+
+required:
+  - compatible
+  - reg
+  - reset-gpios
+  - enable-gpios
+  - pwr-positive5-gpios
+  - pwr-negative5-gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    dsi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        panel@0 {
+            compatible = "truly,nt35521";
+            reg = <0>;
+            reset-gpios = <&msmgpio 25 GPIO_ACTIVE_LOW>;
+            pwr-positive5-gpios = <&msmgpio 114 GPIO_ACTIVE_HIGH>;
+            pwr-negative5-gpios = <&msmgpio 17 GPIO_ACTIVE_HIGH>;
+            enable-gpios = <&msmgpio 10 GPIO_ACTIVE_HIGH>;
+        };
+    };
+...
-- 
2.17.1

`h`	back out one level
`j`	next message in thread
`k`	previous message in thread
`l`	drill in
`Esc`	close help / fold thread tree
`?`	toggle this help