[PATCH 0/4] Add simple-dbi tinydrm driver

[PATCH 0/4] Add simple-dbi tinydrm driver

[Icenowy Zheng]

This patchset adds a tinydrm driver called simple-dbi, which is a driver
that utilizes only standardized commands in MIPI DCS to activate a MIPI
DBI panel that requires no extra configuration, usually because the
configuration is pre-programmed into the OTP of the LCD controller.

Icenowy Zheng (4):
  dt-bindings: vendor-prefixes: add Zhishengxin
  dt-bindings: display: add binding for simple-dbi panels
  drm/tiny: add simple-dbi driver
  MAINTAINERS: add simple-dbi driver

 .../bindings/display/simple-dbi.yaml          |  72 ++++++
 .../devicetree/bindings/vendor-prefixes.yaml  |   2 +
 MAINTAINERS                                   |   7 +
 drivers/gpu/drm/tiny/Kconfig                  |  12 +
 drivers/gpu/drm/tiny/Makefile                 |   1 +
 drivers/gpu/drm/tiny/simple-dbi.c             | 244 ++++++++++++++++++
 6 files changed, 338 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/simple-dbi.yaml
 create mode 100644 drivers/gpu/drm/tiny/simple-dbi.c

-- 
2.30.2

[PATCH 1/4] dt-bindings: vendor-prefixes: add Zhishengxin

[Icenowy Zheng]

Shenzhen Zhishengxin Technology Co., Ltd. is a LCD module supplier.

Add vendor prefix for it.

Signed-off-by: Icenowy Zheng <icenowy@sipeed.com>
---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index 62cb1d9341f5..d8fdec851f38 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -1334,6 +1334,8 @@ patternProperties:
     description: Zinitix Co., Ltd
   "^zkmagic,.*":
     description: Shenzhen Zkmagic Technology Co., Ltd.
+  "^zsx,.*":
+    description: Shenzhen Zhishengxin Technology Co., Ltd.
   "^zte,.*":
     description: ZTE Corp.
   "^zyxel,.*":
-- 
2.30.2

[PATCH 2/4] dt-bindings: display: add binding for simple-dbi panels

[Icenowy Zheng]

As we're going to introduce a driver for MIPI DBI panels that need only
standard MIPI-DCS commands to initialize (usually because the controller
has some configuration pre-programmed), add a DT binding file for it,
which now includes only one DBI Type C Option 3 panel, ZSX154-B1206.

Signed-off-by: Icenowy Zheng <icenowy@sipeed.com>
---
 .../bindings/display/simple-dbi.yaml          | 72 +++++++++++++++++++
 1 file changed, 72 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/simple-dbi.yaml

diff --git a/Documentation/devicetree/bindings/display/simple-dbi.yaml b/Documentation/devicetree/bindings/display/simple-dbi.yaml
new file mode 100644
index 000000000000..f49b0fda0935
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/simple-dbi.yaml
@@ -0,0 +1,72 @@
+# SPDX-License-Identifier: GPL-2.0-only
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/simple-dbi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Generic MIPI DCS-compatible DBI panels Device Tree Bindings
+
+maintainers:
+  - Icenowy Zheng <icenowy@sipeed.com>
+
+description:
+  This binding is for display panels that utilizes MIPI DBI Type C, follows
+  MIPI DCS and needs no vendor-specific initialization commands.
+
+properties:
+  compatible:
+    oneOf:
+      - description:
+          Zhishengxin ZSX154-B1206 1.54" 240x240 SPI LCD
+        items:
+          - const: zsx,zsx154-b1206
+
+  spi-max-frequency:
+    maximum: 30000000
+
+  dc-gpios:
+    maxItems: 1
+    description: Display data/command selection (D/CX)
+
+  backlight: true
+  reg: true
+  reset-gpios: true
+  rotation: true
+
+required:
+  - compatible
+  - reg
+
+allOf:
+  - $ref: panel/panel-common.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: zsx,zsx154-b1206
+
+    then:
+      required:
+        - dc-gpios
+        - reset-gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    spi {
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            display@0 {
+                    compatible = "zsx,zsx154-b1206";
+                    reg = <0>;
+                    spi-max-frequency = <30000000>;
+                    dc-gpios = <&pio 7 4 GPIO_ACTIVE_HIGH>;
+                    reset-gpios = <&r_pio 2 21 GPIO_ACTIVE_HIGH>;
+            };
+    };
+
+...
-- 
2.30.2

[PATCH 3/4] drm/tiny: add simple-dbi driver

[Icenowy Zheng]

Add a driver for generic MIPI DBI panels initialized with MIPI DCS
commands.

Currently a ST7789V-based panel is added to it. This panel has its
configuration pre-programmed into the controller, so no vendor-specific
configuration is needed.

Signed-off-by: Icenowy Zheng <icenowy@sipeed.com>
---
 drivers/gpu/drm/tiny/Kconfig      |  12 ++
 drivers/gpu/drm/tiny/Makefile     |   1 +
 drivers/gpu/drm/tiny/simple-dbi.c | 244 ++++++++++++++++++++++++++++++
 3 files changed, 257 insertions(+)
 create mode 100644 drivers/gpu/drm/tiny/simple-dbi.c

diff --git a/drivers/gpu/drm/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig
index d31be274a2bd..6cfc57b68a46 100644
--- a/drivers/gpu/drm/tiny/Kconfig
+++ b/drivers/gpu/drm/tiny/Kconfig
@@ -144,6 +144,18 @@ config TINYDRM_REPAPER
 
 	  If M is selected the module will be called repaper.
 
+config TINYDRM_SIMPLE_DBI
+	tristate "DRM support for generic MIPI DBI panels"
+	depends on DRM && SPI
+	select DRM_KMS_HELPER
+	select DRM_KMS_CMA_HELPER
+	select DRM_MIPI_DBI
+	help
+	  DRM driver for generic DBI panels that are MIPI DCS compatible
+	  and needs no vendor-specific setup commands.
+
+	  If M is selected the module will be called simple-dbi.
+
 config TINYDRM_ST7586
 	tristate "DRM support for Sitronix ST7586 display panels"
 	depends on DRM && SPI
diff --git a/drivers/gpu/drm/tiny/Makefile b/drivers/gpu/drm/tiny/Makefile
index e09942895c77..2553de651aa3 100644
--- a/drivers/gpu/drm/tiny/Makefile
+++ b/drivers/gpu/drm/tiny/Makefile
@@ -13,3 +13,4 @@ obj-$(CONFIG_TINYDRM_MI0283QT)		+= mi0283qt.o
 obj-$(CONFIG_TINYDRM_REPAPER)		+= repaper.o
 obj-$(CONFIG_TINYDRM_ST7586)		+= st7586.o
 obj-$(CONFIG_TINYDRM_ST7735R)		+= st7735r.o
+obj-$(CONFIG_TINYDRM_SIMPLE_DBI)	+= simple-dbi.o
diff --git a/drivers/gpu/drm/tiny/simple-dbi.c b/drivers/gpu/drm/tiny/simple-dbi.c
new file mode 100644
index 000000000000..2b207e43d500
--- /dev/null
+++ b/drivers/gpu/drm/tiny/simple-dbi.c
@@ -0,0 +1,244 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * DRM driver for display panels with configuration preset and needs only
+ * standard MIPI DCS commands to bring up.
+ *
+ * Copyright (C) 2021 Sipeed
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/dma-buf.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/spi/spi.h>
+#include <video/mipi_display.h>
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_gem_atomic_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_managed.h>
+#include <drm/drm_mipi_dbi.h>
+
+#define MIPI_DCS_ADDRESS_MODE_BGR		BIT(3)
+#define MIPI_DCS_ADDRESS_MODE_REVERSE		BIT(5)
+#define MIPI_DCS_ADDRESS_MODE_RTL		BIT(6)
+#define MIPI_DCS_ADDRESS_MODE_BTT		BIT(7)
+
+struct simple_dbi_cfg {
+	const struct drm_display_mode mode;
+	unsigned int left_offset;
+	unsigned int top_offset;
+	bool inverted;
+	bool write_only;
+	bool bgr;
+	bool right_to_left;
+	bool bottom_to_top;
+};
+
+struct simple_dbi_priv {
+	struct mipi_dbi_dev dbidev;	/* Must be first for .release() */
+	const struct simple_dbi_cfg *cfg;
+};
+
+static void simple_dbi_pipe_enable(struct drm_simple_display_pipe *pipe,
+				struct drm_crtc_state *crtc_state,
+				struct drm_plane_state *plane_state)
+{
+	struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
+	struct simple_dbi_priv *priv = container_of(dbidev,
+						    struct simple_dbi_priv,
+						    dbidev);
+	struct mipi_dbi *dbi = &dbidev->dbi;
+	int ret, idx;
+	u8 addr_mode = 0x00;
+
+	if (!drm_dev_enter(pipe->crtc.dev, &idx))
+		return;
+
+	DRM_DEBUG_KMS("\n");
+
+	ret = mipi_dbi_poweron_reset(dbidev);
+	if (ret)
+		goto out_exit;
+
+	mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
+	msleep(5);
+
+	/* Currently tinydrm supports 16bit only now */
+	mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT,
+			 MIPI_DCS_PIXEL_FMT_16BIT);
+
+	if (priv->cfg->inverted)
+		mipi_dbi_command(dbi, MIPI_DCS_ENTER_INVERT_MODE);
+	else
+		mipi_dbi_command(dbi, MIPI_DCS_EXIT_INVERT_MODE);
+
+	if (priv->cfg->bgr)
+		addr_mode |= MIPI_DCS_ADDRESS_MODE_BGR;
+
+	if (priv->cfg->right_to_left)
+		addr_mode |= MIPI_DCS_ADDRESS_MODE_RTL;
+
+	if (priv->cfg->bottom_to_top)
+		addr_mode |= MIPI_DCS_ADDRESS_MODE_BTT;
+
+	switch (dbidev->rotation) {
+	default:
+		break;
+	case 90:
+		addr_mode ^= MIPI_DCS_ADDRESS_MODE_REVERSE;
+		addr_mode ^= MIPI_DCS_ADDRESS_MODE_RTL;
+		break;
+	case 180:
+		addr_mode ^= MIPI_DCS_ADDRESS_MODE_RTL;
+		addr_mode ^= MIPI_DCS_ADDRESS_MODE_BTT;
+		break;
+	case 270:
+		addr_mode ^= MIPI_DCS_ADDRESS_MODE_REVERSE;
+		addr_mode ^= MIPI_DCS_ADDRESS_MODE_BTT;
+		break;
+	}
+
+	mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
+
+	mipi_dbi_command(dbi, MIPI_DCS_ENTER_NORMAL_MODE);
+
+	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
+
+	mipi_dbi_enable_flush(dbidev, crtc_state, plane_state);
+out_exit:
+	drm_dev_exit(idx);
+}
+
+static const struct drm_simple_display_pipe_funcs simple_dbi_pipe_funcs = {
+	.enable		= simple_dbi_pipe_enable,
+	.disable	= mipi_dbi_pipe_disable,
+	.update		= mipi_dbi_pipe_update,
+	.prepare_fb	= drm_gem_simple_display_pipe_prepare_fb,
+};
+
+static const struct simple_dbi_cfg zsx154_b1206_cfg = {
+	.mode		= { DRM_SIMPLE_MODE(240, 240, 28, 28) },
+	.inverted	= true,
+	.write_only	= true,
+};
+
+DEFINE_DRM_GEM_CMA_FOPS(simple_dbi_fops);
+
+static const struct drm_driver simple_dbi_driver = {
+	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
+	.fops			= &simple_dbi_fops,
+	DRM_GEM_CMA_DRIVER_OPS_VMAP,
+	.debugfs_init		= mipi_dbi_debugfs_init,
+	.name			= "simple-dbi",
+	.desc			= "Generic MIPI-DCS compatible DBI panel",
+	.date			= "20210723",
+	.major			= 1,
+	.minor			= 0,
+};
+
+static const struct of_device_id simple_dbi_of_match[] = {
+	{ .compatible = "zsx,zsx154-b1206", .data = &zsx154_b1206_cfg },
+	{ },
+}
+MODULE_DEVICE_TABLE(of, simple_dbi_of_match);
+
+static int simple_dbi_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	const struct simple_dbi_cfg *cfg;
+	struct mipi_dbi_dev *dbidev;
+	struct simple_dbi_priv *priv;
+	struct drm_device *drm;
+	struct mipi_dbi *dbi;
+	struct gpio_desc *dc;
+	u32 rotation = 0;
+	int ret;
+
+	cfg = device_get_match_data(&spi->dev);
+	if (!cfg)
+		cfg = (void *)spi_get_device_id(spi)->driver_data;
+
+	priv = devm_drm_dev_alloc(dev, &simple_dbi_driver,
+				  struct simple_dbi_priv, dbidev.drm);
+	if (IS_ERR(priv))
+		return PTR_ERR(priv);
+
+	dbidev = &priv->dbidev;
+	priv->cfg = cfg;
+
+	dbi = &dbidev->dbi;
+	drm = &dbidev->drm;
+
+	dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(dbi->reset))
+		return dev_err_probe(dev, PTR_ERR(dbi->reset), "Failed to get reset GPIO\n");
+
+	dc = devm_gpiod_get_optional(dev, "dc", GPIOD_OUT_LOW);
+	if (IS_ERR(dc))
+		return dev_err_probe(dev, PTR_ERR(dc), "Failed to get D/C GPIO\n");
+
+	dbidev->backlight = devm_of_find_backlight(dev);
+	if (IS_ERR(dbidev->backlight))
+		return PTR_ERR(dbidev->backlight);
+
+	device_property_read_u32(dev, "rotation", &rotation);
+
+	ret = mipi_dbi_spi_init(spi, dbi, dc);
+	if (ret)
+		return ret;
+
+	if (cfg->write_only)
+		dbi->read_commands = NULL;
+
+	ret = mipi_dbi_dev_init(dbidev, &simple_dbi_pipe_funcs, &cfg->mode,
+				rotation);
+	if (ret)
+		return ret;
+
+	drm_mode_config_reset(drm);
+
+	ret = drm_dev_register(drm, 0);
+	if (ret)
+		return ret;
+
+	spi_set_drvdata(spi, drm);
+
+	drm_fbdev_generic_setup(drm, 0);
+
+	return 0;
+}
+
+static int simple_dbi_remove(struct spi_device *spi)
+{
+	struct drm_device *drm = spi_get_drvdata(spi);
+
+	drm_dev_unplug(drm);
+	drm_atomic_helper_shutdown(drm);
+
+	return 0;
+}
+
+static void simple_dbi_shutdown(struct spi_device *spi)
+{
+	drm_atomic_helper_shutdown(spi_get_drvdata(spi));
+}
+
+static struct spi_driver simple_dbi_spi_driver = {
+	.driver = {
+		.name = "simple-dbi",
+		.of_match_table = simple_dbi_of_match,
+	},
+	.probe = simple_dbi_probe,
+	.remove = simple_dbi_remove,
+	.shutdown = simple_dbi_shutdown,
+};
+module_spi_driver(simple_dbi_spi_driver);
+
+MODULE_DESCRIPTION("Simple DBI panel DRM driver");
+MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>");
+MODULE_LICENSE("GPL");
-- 
2.30.2

[PATCH 4/4] MAINTAINERS: add simple-dbi driver

[Icenowy Zheng]

As I pushed the simple-dbi driver, add myself as the maintainer now.

Signed-off-by: Icenowy Zheng <icenowy@sipeed.com>
---
 MAINTAINERS | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 3a00771b9fe2..e05c4910c062 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5803,6 +5803,13 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/display/panel/feiyang,fy07024di26a30d.yaml
 F:	drivers/gpu/drm/panel/panel-feiyang-fy07024di26a30d.c
 
+DRM DRIVER FOR GENERIC MIPI-DBI LCD PANELS
+M:	Icenowy Zheng <icenowy@sipeed.com>
+S:	Maintained
+T:	git git://anongit.freedesktop.org/drm/drm-misc
+F:	Documentation/devicetree/bindings/display/simple-dbi.yaml
+F:	drivers/gpu/drm/tiny/simple-dbi.c
+
 DRM DRIVER FOR GENERIC USB DISPLAY
 M:	Noralf Trønnes <noralf@tronnes.org>
 S:	Maintained
-- 
2.30.2

Re: [PATCH 3/4] drm/tiny: add simple-dbi driver

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 3201 bytes --]

Hi Icenowy,

I love your patch! Yet something to improve:

[auto build test ERROR on robh/for-next]
[also build test ERROR on drm-intel/for-linux-next drm-tip/drm-tip linus/master v5.14-rc3 next-20210730]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Icenowy-Zheng/Add-simple-dbi-tinydrm-driver/20210802-144017
base:   https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
config: m68k-allmodconfig (attached as .config)
compiler: m68k-linux-gcc (GCC) 10.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/257b1975790880588d1ec7cfec4ebde54d23d63a
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Icenowy-Zheng/Add-simple-dbi-tinydrm-driver/20210802-144017
        git checkout 257b1975790880588d1ec7cfec4ebde54d23d63a
        # save the attached .config to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross O=build_dir ARCH=m68k SHELL=/bin/bash drivers/gpu/drm/tiny/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from include/linux/kallsyms.h:14,
                    from include/linux/ftrace.h:12,
                    from include/linux/kprobes.h:29,
                    from include/linux/kgdb.h:19,
                    from include/linux/fb.h:5,
                    from include/linux/backlight.h:13,
                    from drivers/gpu/drm/tiny/simple-dbi.c:9:
>> include/linux/module.h:244:1: error: expected ',' or ';' before 'extern'
     244 | extern typeof(name) __mod_##type##__##name##_device_table  \
         | ^~~~~~
   drivers/gpu/drm/tiny/simple-dbi.c:148:1: note: in expansion of macro 'MODULE_DEVICE_TABLE'
     148 | MODULE_DEVICE_TABLE(of, simple_dbi_of_match);
         | ^~~~~~~~~~~~~~~~~~~


vim +244 include/linux/module.h

^1da177e4c3f41 Linus Torvalds    2005-04-16  240  
cff26a51da5d20 Rusty Russell     2014-02-03  241  #ifdef MODULE
cff26a51da5d20 Rusty Russell     2014-02-03  242  /* Creates an alias so file2alias.c can find device table. */
^1da177e4c3f41 Linus Torvalds    2005-04-16  243  #define MODULE_DEVICE_TABLE(type, name)					\
0bf8bf50eddc75 Matthias Kaehlcke 2017-07-24 @244  extern typeof(name) __mod_##type##__##name##_device_table		\
cff26a51da5d20 Rusty Russell     2014-02-03  245    __attribute__ ((unused, alias(__stringify(name))))
cff26a51da5d20 Rusty Russell     2014-02-03  246  #else  /* !MODULE */
cff26a51da5d20 Rusty Russell     2014-02-03  247  #define MODULE_DEVICE_TABLE(type, name)
cff26a51da5d20 Rusty Russell     2014-02-03  248  #endif
^1da177e4c3f41 Linus Torvalds    2005-04-16  249  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
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Re: [PATCH 3/4] drm/tiny: add simple-dbi driver

[Thomas Zimmermann]

[-- Attachment #1.1: Type: text/plain, Size: 9669 bytes --]

Hi

Am 02.08.21 um 08:35 schrieb Icenowy Zheng:
> Add a driver for generic MIPI DBI panels initialized with MIPI DCS
> commands.
> 
> Currently a ST7789V-based panel is added to it. This panel has its
> configuration pre-programmed into the controller, so no vendor-specific
> configuration is needed.
> 
> Signed-off-by: Icenowy Zheng <icenowy@sipeed.com>
> ---
>   drivers/gpu/drm/tiny/Kconfig      |  12 ++
>   drivers/gpu/drm/tiny/Makefile     |   1 +
>   drivers/gpu/drm/tiny/simple-dbi.c | 244 ++++++++++++++++++++++++++++++
>   3 files changed, 257 insertions(+)
>   create mode 100644 drivers/gpu/drm/tiny/simple-dbi.c
> 
> diff --git a/drivers/gpu/drm/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig
> index d31be274a2bd..6cfc57b68a46 100644
> --- a/drivers/gpu/drm/tiny/Kconfig
> +++ b/drivers/gpu/drm/tiny/Kconfig
> @@ -144,6 +144,18 @@ config TINYDRM_REPAPER
>   
>   	  If M is selected the module will be called repaper.
>   
> +config TINYDRM_SIMPLE_DBI
> +	tristate "DRM support for generic MIPI DBI panels"
> +	depends on DRM && SPI
> +	select DRM_KMS_HELPER
> +	select DRM_KMS_CMA_HELPER
> +	select DRM_MIPI_DBI
> +	help
> +	  DRM driver for generic DBI panels that are MIPI DCS compatible
> +	  and needs no vendor-specific setup commands.
> +
> +	  If M is selected the module will be called simple-dbi.
> +
>   config TINYDRM_ST7586
>   	tristate "DRM support for Sitronix ST7586 display panels"
>   	depends on DRM && SPI
> diff --git a/drivers/gpu/drm/tiny/Makefile b/drivers/gpu/drm/tiny/Makefile
> index e09942895c77..2553de651aa3 100644
> --- a/drivers/gpu/drm/tiny/Makefile
> +++ b/drivers/gpu/drm/tiny/Makefile
> @@ -13,3 +13,4 @@ obj-$(CONFIG_TINYDRM_MI0283QT)		+= mi0283qt.o
>   obj-$(CONFIG_TINYDRM_REPAPER)		+= repaper.o
>   obj-$(CONFIG_TINYDRM_ST7586)		+= st7586.o
>   obj-$(CONFIG_TINYDRM_ST7735R)		+= st7735r.o
> +obj-$(CONFIG_TINYDRM_SIMPLE_DBI)	+= simple-dbi.o
> diff --git a/drivers/gpu/drm/tiny/simple-dbi.c b/drivers/gpu/drm/tiny/simple-dbi.c
> new file mode 100644
> index 000000000000..2b207e43d500
> --- /dev/null
> +++ b/drivers/gpu/drm/tiny/simple-dbi.c
> @@ -0,0 +1,244 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * DRM driver for display panels with configuration preset and needs only
> + * standard MIPI DCS commands to bring up.
> + *
> + * Copyright (C) 2021 Sipeed
> + */
> +
> +#include <linux/backlight.h>
> +#include <linux/delay.h>
> +#include <linux/dma-buf.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/module.h>
> +#include <linux/property.h>
> +#include <linux/spi/spi.h>
> +#include <video/mipi_display.h>
> +
> +#include <drm/drm_atomic_helper.h>
> +#include <drm/drm_drv.h>
> +#include <drm/drm_fb_helper.h>
> +#include <drm/drm_gem_atomic_helper.h>
> +#include <drm/drm_gem_cma_helper.h>
> +#include <drm/drm_managed.h>
> +#include <drm/drm_mipi_dbi.h>
> +
> +#define MIPI_DCS_ADDRESS_MODE_BGR		BIT(3)
> +#define MIPI_DCS_ADDRESS_MODE_REVERSE		BIT(5)
> +#define MIPI_DCS_ADDRESS_MODE_RTL		BIT(6)
> +#define MIPI_DCS_ADDRESS_MODE_BTT		BIT(7)
> +
> +struct simple_dbi_cfg {
> +	const struct drm_display_mode mode;
> +	unsigned int left_offset;
> +	unsigned int top_offset;
> +	bool inverted;
> +	bool write_only;
> +	bool bgr;
> +	bool right_to_left;
> +	bool bottom_to_top;
> +};
> +
> +struct simple_dbi_priv {
> +	struct mipi_dbi_dev dbidev;	/* Must be first for .release() */

Which release?

> +	const struct simple_dbi_cfg *cfg;
> +};
> +
> +static void simple_dbi_pipe_enable(struct drm_simple_display_pipe *pipe,
> +				struct drm_crtc_state *crtc_state,
> +				struct drm_plane_state *plane_state)
> +{
> +	struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe->crtc.dev);
> +	struct simple_dbi_priv *priv = container_of(dbidev,
> +						    struct simple_dbi_priv,
> +						    dbidev);
> +	struct mipi_dbi *dbi = &dbidev->dbi;
> +	int ret, idx;
> +	u8 addr_mode = 0x00;
> +
> +	if (!drm_dev_enter(pipe->crtc.dev, &idx))
> +		return;
> +
> +	DRM_DEBUG_KMS("\n");

I'm not a friend of such debugging statements. If you absolutely want to 
keep it, rather use drm_dbg_kms().

> +
> +	ret = mipi_dbi_poweron_reset(dbidev);
> +	if (ret)
> +		goto out_exit;
> +
> +	mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
> +	msleep(5);
> +
> +	/* Currently tinydrm supports 16bit only now */
> +	mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT,
> +			 MIPI_DCS_PIXEL_FMT_16BIT);
> +
> +	if (priv->cfg->inverted)
> +		mipi_dbi_command(dbi, MIPI_DCS_ENTER_INVERT_MODE);
> +	else
> +		mipi_dbi_command(dbi, MIPI_DCS_EXIT_INVERT_MODE);
> +
> +	if (priv->cfg->bgr)
> +		addr_mode |= MIPI_DCS_ADDRESS_MODE_BGR;
> +
> +	if (priv->cfg->right_to_left)
> +		addr_mode |= MIPI_DCS_ADDRESS_MODE_RTL;
> +
> +	if (priv->cfg->bottom_to_top)
> +		addr_mode |= MIPI_DCS_ADDRESS_MODE_BTT;
> +
> +	switch (dbidev->rotation) {
> +	default:
> +		break;
> +	case 90:
> +		addr_mode ^= MIPI_DCS_ADDRESS_MODE_REVERSE;
> +		addr_mode ^= MIPI_DCS_ADDRESS_MODE_RTL;
> +		break;
> +	case 180:
> +		addr_mode ^= MIPI_DCS_ADDRESS_MODE_RTL;
> +		addr_mode ^= MIPI_DCS_ADDRESS_MODE_BTT;
> +		break;
> +	case 270:
> +		addr_mode ^= MIPI_DCS_ADDRESS_MODE_REVERSE;
> +		addr_mode ^= MIPI_DCS_ADDRESS_MODE_BTT;
> +		break;
> +	}
> +
> +	mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
> +
> +	mipi_dbi_command(dbi, MIPI_DCS_ENTER_NORMAL_MODE);
> +
> +	mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
> +
> +	mipi_dbi_enable_flush(dbidev, crtc_state, plane_state);
> +out_exit:
> +	drm_dev_exit(idx);
> +}
> +
> +static const struct drm_simple_display_pipe_funcs simple_dbi_pipe_funcs = {
> +	.enable		= simple_dbi_pipe_enable,
> +	.disable	= mipi_dbi_pipe_disable,
> +	.update		= mipi_dbi_pipe_update,
> +	.prepare_fb	= drm_gem_simple_display_pipe_prepare_fb,
> +};
> +
> +static const struct simple_dbi_cfg zsx154_b1206_cfg = {
> +	.mode		= { DRM_SIMPLE_MODE(240, 240, 28, 28) },
> +	.inverted	= true,
> +	.write_only	= true,
> +};
> +
> +DEFINE_DRM_GEM_CMA_FOPS(simple_dbi_fops);
> +
> +static const struct drm_driver simple_dbi_driver = {
> +	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
> +	.fops			= &simple_dbi_fops,
> +	DRM_GEM_CMA_DRIVER_OPS_VMAP,
> +	.debugfs_init		= mipi_dbi_debugfs_init,
> +	.name			= "simple-dbi",
> +	.desc			= "Generic MIPI-DCS compatible DBI panel",
> +	.date			= "20210723",
> +	.major			= 1,
> +	.minor			= 0,
> +};
> +
> +static const struct of_device_id simple_dbi_of_match[] = {
> +	{ .compatible = "zsx,zsx154-b1206", .data = &zsx154_b1206_cfg },
> +	{ },
> +}
> +MODULE_DEVICE_TABLE(of, simple_dbi_of_match);
> +
> +static int simple_dbi_probe(struct spi_device *spi)
> +{
> +	struct device *dev = &spi->dev;
> +	const struct simple_dbi_cfg *cfg;
> +	struct mipi_dbi_dev *dbidev;
> +	struct simple_dbi_priv *priv;
> +	struct drm_device *drm;
> +	struct mipi_dbi *dbi;
> +	struct gpio_desc *dc;
> +	u32 rotation = 0;
> +	int ret;
> +
> +	cfg = device_get_match_data(&spi->dev);
> +	if (!cfg)
> +		cfg = (void *)spi_get_device_id(spi)->driver_data;
> +
> +	priv = devm_drm_dev_alloc(dev, &simple_dbi_driver,
> +				  struct simple_dbi_priv, dbidev.drm);
> +	if (IS_ERR(priv))
> +		return PTR_ERR(priv);
> +
> +	dbidev = &priv->dbidev;
> +	priv->cfg = cfg;
> +
> +	dbi = &dbidev->dbi;
> +	drm = &dbidev->drm;
> +
> +	dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
> +	if (IS_ERR(dbi->reset))
> +		return dev_err_probe(dev, PTR_ERR(dbi->reset), "Failed to get reset GPIO\n");
> +
> +	dc = devm_gpiod_get_optional(dev, "dc", GPIOD_OUT_LOW);
> +	if (IS_ERR(dc))
> +		return dev_err_probe(dev, PTR_ERR(dc), "Failed to get D/C GPIO\n");
> +
> +	dbidev->backlight = devm_of_find_backlight(dev);
> +	if (IS_ERR(dbidev->backlight))
> +		return PTR_ERR(dbidev->backlight);
> +
> +	device_property_read_u32(dev, "rotation", &rotation);
> +
> +	ret = mipi_dbi_spi_init(spi, dbi, dc);
> +	if (ret)
> +		return ret;
> +
> +	if (cfg->write_only)
> +		dbi->read_commands = NULL;
> +
> +	ret = mipi_dbi_dev_init(dbidev, &simple_dbi_pipe_funcs, &cfg->mode,
> +				rotation);
> +	if (ret)
> +		return ret;
> +
> +	drm_mode_config_reset(drm);
> +
> +	ret = drm_dev_register(drm, 0);
> +	if (ret)
> +		return ret;
> +
> +	spi_set_drvdata(spi, drm);

AFAIK dev files are being created during drm_dev_register(). It's 
probably safer to set the drvdata before.

> +
> +	drm_fbdev_generic_setup(drm, 0);
> +
> +	return 0;
> +}
> +
> +static int simple_dbi_remove(struct spi_device *spi)
> +{
> +	struct drm_device *drm = spi_get_drvdata(spi);
> +
> +	drm_dev_unplug(drm);
> +	drm_atomic_helper_shutdown(drm);
> +
> +	return 0;
> +}
> +
> +static void simple_dbi_shutdown(struct spi_device *spi)
> +{
> +	drm_atomic_helper_shutdown(spi_get_drvdata(spi));
> +}
> +
> +static struct spi_driver simple_dbi_spi_driver = {
> +	.driver = {
> +		.name = "simple-dbi",
> +		.of_match_table = simple_dbi_of_match,
> +	},
> +	.probe = simple_dbi_probe,
> +	.remove = simple_dbi_remove,
> +	.shutdown = simple_dbi_shutdown,
> +};
> +module_spi_driver(simple_dbi_spi_driver);
> +
> +MODULE_DESCRIPTION("Simple DBI panel DRM driver");
> +MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>");
> +MODULE_LICENSE("GPL");
> 

Trailing blank line. (?)

Best regards
Thomas

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer


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Re: [PATCH 3/4] drm/tiny: add simple-dbi driver

[Thomas Zimmermann]

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Hi

Am 03.08.21 um 03:25 schrieb Icenowy Zheng:
> 在 2021-08-02星期一的 17:08 +0200，Thomas Zimmermann写道：
>> Hi
>>
>> Am 02.08.21 um 08:35 schrieb Icenowy Zheng:
>>> Add a driver for generic MIPI DBI panels initialized with MIPI DCS
>>> commands.
>>>
>>> Currently a ST7789V-based panel is added to it. This panel has its
>>> configuration pre-programmed into the controller, so no vendor-
>>> specific
>>> configuration is needed.
>>>
>>> Signed-off-by: Icenowy Zheng <icenowy@sipeed.com>
>>> ---
>>>    drivers/gpu/drm/tiny/Kconfig      |  12 ++
>>>    drivers/gpu/drm/tiny/Makefile     |   1 +
>>>    drivers/gpu/drm/tiny/simple-dbi.c | 244
>>> ++++++++++++++++++++++++++++++
>>>    3 files changed, 257 insertions(+)
>>>    create mode 100644 drivers/gpu/drm/tiny/simple-dbi.c
>>>
>>> diff --git a/drivers/gpu/drm/tiny/Kconfig
>>> b/drivers/gpu/drm/tiny/Kconfig
>>> index d31be274a2bd..6cfc57b68a46 100644
>>> --- a/drivers/gpu/drm/tiny/Kconfig
>>> +++ b/drivers/gpu/drm/tiny/Kconfig
>>> @@ -144,6 +144,18 @@ config TINYDRM_REPAPER
>>>    
>>>            If M is selected the module will be called repaper.
>>>    
>>> +config TINYDRM_SIMPLE_DBI
>>> +       tristate "DRM support for generic MIPI DBI panels"
>>> +       depends on DRM && SPI
>>> +       select DRM_KMS_HELPER
>>> +       select DRM_KMS_CMA_HELPER
>>> +       select DRM_MIPI_DBI
>>> +       help
>>> +         DRM driver for generic DBI panels that are MIPI DCS
>>> compatible
>>> +         and needs no vendor-specific setup commands.
>>> +
>>> +         If M is selected the module will be called simple-dbi.
>>> +
>>>    config TINYDRM_ST7586
>>>          tristate "DRM support for Sitronix ST7586 display panels"
>>>          depends on DRM && SPI
>>> diff --git a/drivers/gpu/drm/tiny/Makefile
>>> b/drivers/gpu/drm/tiny/Makefile
>>> index e09942895c77..2553de651aa3 100644
>>> --- a/drivers/gpu/drm/tiny/Makefile
>>> +++ b/drivers/gpu/drm/tiny/Makefile
>>> @@ -13,3 +13,4 @@ obj-$(CONFIG_TINYDRM_MI0283QT)                +=
>>> mi0283qt.o
>>>    obj-$(CONFIG_TINYDRM_REPAPER)         += repaper.o
>>>    obj-$(CONFIG_TINYDRM_ST7586)          += st7586.o
>>>    obj-$(CONFIG_TINYDRM_ST7735R)         += st7735r.o
>>> +obj-$(CONFIG_TINYDRM_SIMPLE_DBI)       += simple-dbi.o
>>> diff --git a/drivers/gpu/drm/tiny/simple-dbi.c
>>> b/drivers/gpu/drm/tiny/simple-dbi.c
>>> new file mode 100644
>>> index 000000000000..2b207e43d500
>>> --- /dev/null
>>> +++ b/drivers/gpu/drm/tiny/simple-dbi.c
>>> @@ -0,0 +1,244 @@
>>> +// SPDX-License-Identifier: GPL-2.0+
>>> +/*
>>> + * DRM driver for display panels with configuration preset and
>>> needs only
>>> + * standard MIPI DCS commands to bring up.
>>> + *
>>> + * Copyright (C) 2021 Sipeed
>>> + */
>>> +
>>> +#include <linux/backlight.h>
>>> +#include <linux/delay.h>
>>> +#include <linux/dma-buf.h>
>>> +#include <linux/gpio/consumer.h>
>>> +#include <linux/module.h>
>>> +#include <linux/property.h>
>>> +#include <linux/spi/spi.h>
>>> +#include <video/mipi_display.h>
>>> +
>>> +#include <drm/drm_atomic_helper.h>
>>> +#include <drm/drm_drv.h>
>>> +#include <drm/drm_fb_helper.h>
>>> +#include <drm/drm_gem_atomic_helper.h>
>>> +#include <drm/drm_gem_cma_helper.h>
>>> +#include <drm/drm_managed.h>
>>> +#include <drm/drm_mipi_dbi.h>
>>> +
>>> +#define MIPI_DCS_ADDRESS_MODE_BGR              BIT(3)
>>> +#define MIPI_DCS_ADDRESS_MODE_REVERSE          BIT(5)
>>> +#define MIPI_DCS_ADDRESS_MODE_RTL              BIT(6)
>>> +#define MIPI_DCS_ADDRESS_MODE_BTT              BIT(7)
>>> +
>>> +struct simple_dbi_cfg {
>>> +       const struct drm_display_mode mode;
>>> +       unsigned int left_offset;
>>> +       unsigned int top_offset;
>>> +       bool inverted;
>>> +       bool write_only;
>>> +       bool bgr;
>>> +       bool right_to_left;
>>> +       bool bottom_to_top;
>>> +};
>>> +
>>> +struct simple_dbi_priv {
>>> +       struct mipi_dbi_dev dbidev;     /* Must be first for
>>> .release() */
>>
>> Which release?
> 
> Ah, some copy-n-paste waste.
> 
> Will drop this in v2.
> 
>>
>>> +       const struct simple_dbi_cfg *cfg;
>>> +};
>>> +
>>> +static void simple_dbi_pipe_enable(struct drm_simple_display_pipe
>>> *pipe,
>>> +                               struct drm_crtc_state *crtc_state,
>>> +                               struct drm_plane_state
>>> *plane_state)
>>> +{
>>> +       struct mipi_dbi_dev *dbidev = drm_to_mipi_dbi_dev(pipe-
>>>> crtc.dev);
>>> +       struct simple_dbi_priv *priv = container_of(dbidev,
>>> +                                                   struct
>>> simple_dbi_priv,
>>> +                                                   dbidev);
>>> +       struct mipi_dbi *dbi = &dbidev->dbi;
>>> +       int ret, idx;
>>> +       u8 addr_mode = 0x00;
>>> +
>>> +       if (!drm_dev_enter(pipe->crtc.dev, &idx))
>>> +               return;
>>> +
>>> +       DRM_DEBUG_KMS("\n");
>>
>> I'm not a friend of such debugging statements. If you absolutely want
>> to
>> keep it, rather use drm_dbg_kms().
> 
> Should be copy-n-paste waste too.
> 
>>
>>> +
>>> +       ret = mipi_dbi_poweron_reset(dbidev);
>>> +       if (ret)
>>> +               goto out_exit;
>>> +
>>> +       mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
>>> +       msleep(5);
>>> +
>>> +       /* Currently tinydrm supports 16bit only now */
>>> +       mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT,
>>> +                        MIPI_DCS_PIXEL_FMT_16BIT);
>>> +
>>> +       if (priv->cfg->inverted)
>>> +               mipi_dbi_command(dbi, MIPI_DCS_ENTER_INVERT_MODE);
>>> +       else
>>> +               mipi_dbi_command(dbi, MIPI_DCS_EXIT_INVERT_MODE);
>>> +
>>> +       if (priv->cfg->bgr)
>>> +               addr_mode |= MIPI_DCS_ADDRESS_MODE_BGR;
>>> +
>>> +       if (priv->cfg->right_to_left)
>>> +               addr_mode |= MIPI_DCS_ADDRESS_MODE_RTL;
>>> +
>>> +       if (priv->cfg->bottom_to_top)
>>> +               addr_mode |= MIPI_DCS_ADDRESS_MODE_BTT;
>>> +
>>> +       switch (dbidev->rotation) {
>>> +       default:
>>> +               break;
>>> +       case 90:
>>> +               addr_mode ^= MIPI_DCS_ADDRESS_MODE_REVERSE;
>>> +               addr_mode ^= MIPI_DCS_ADDRESS_MODE_RTL;
>>> +               break;
>>> +       case 180:
>>> +               addr_mode ^= MIPI_DCS_ADDRESS_MODE_RTL;
>>> +               addr_mode ^= MIPI_DCS_ADDRESS_MODE_BTT;
>>> +               break;
>>> +       case 270:
>>> +               addr_mode ^= MIPI_DCS_ADDRESS_MODE_REVERSE;
>>> +               addr_mode ^= MIPI_DCS_ADDRESS_MODE_BTT;
>>> +               break;
>>> +       }
>>> +
>>> +       mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE,
>>> addr_mode);
>>> +
>>> +       mipi_dbi_command(dbi, MIPI_DCS_ENTER_NORMAL_MODE);
>>> +
>>> +       mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
>>> +
>>> +       mipi_dbi_enable_flush(dbidev, crtc_state, plane_state);
>>> +out_exit:
>>> +       drm_dev_exit(idx);
>>> +}
>>> +
>>> +static const struct drm_simple_display_pipe_funcs
>>> simple_dbi_pipe_funcs = {
>>> +       .enable         = simple_dbi_pipe_enable,
>>> +       .disable        = mipi_dbi_pipe_disable,
>>> +       .update         = mipi_dbi_pipe_update,
>>> +       .prepare_fb     = drm_gem_simple_display_pipe_prepare_fb,
>>> +};
>>> +
>>> +static const struct simple_dbi_cfg zsx154_b1206_cfg = {
>>> +       .mode           = { DRM_SIMPLE_MODE(240, 240, 28, 28) },
>>> +       .inverted       = true,
>>> +       .write_only     = true,
>>> +};
>>> +
>>> +DEFINE_DRM_GEM_CMA_FOPS(simple_dbi_fops);
>>> +
>>> +static const struct drm_driver simple_dbi_driver = {
>>> +       .driver_features        = DRIVER_GEM | DRIVER_MODESET |
>>> DRIVER_ATOMIC,
>>> +       .fops                   = &simple_dbi_fops,
>>> +       DRM_GEM_CMA_DRIVER_OPS_VMAP,
>>> +       .debugfs_init           = mipi_dbi_debugfs_init,
>>> +       .name                   = "simple-dbi",
>>> +       .desc                   = "Generic MIPI-DCS compatible DBI
>>> panel",
>>> +       .date                   = "20210723",
>>> +       .major                  = 1,
>>> +       .minor                  = 0,
>>> +};
>>> +
>>> +static const struct of_device_id simple_dbi_of_match[] = {
>>> +       { .compatible = "zsx,zsx154-b1206", .data =
>>> &zsx154_b1206_cfg },
>>> +       { },
>>> +}
>>> +MODULE_DEVICE_TABLE(of, simple_dbi_of_match);
>>> +
>>> +static int simple_dbi_probe(struct spi_device *spi)
>>> +{
>>> +       struct device *dev = &spi->dev;
>>> +       const struct simple_dbi_cfg *cfg;
>>> +       struct mipi_dbi_dev *dbidev;
>>> +       struct simple_dbi_priv *priv;
>>> +       struct drm_device *drm;
>>> +       struct mipi_dbi *dbi;
>>> +       struct gpio_desc *dc;
>>> +       u32 rotation = 0;
>>> +       int ret;
>>> +
>>> +       cfg = device_get_match_data(&spi->dev);
>>> +       if (!cfg)
>>> +               cfg = (void *)spi_get_device_id(spi)->driver_data;
>>> +
>>> +       priv = devm_drm_dev_alloc(dev, &simple_dbi_driver,
>>> +                                 struct simple_dbi_priv,
>>> dbidev.drm);
>>> +       if (IS_ERR(priv))
>>> +               return PTR_ERR(priv);
>>> +
>>> +       dbidev = &priv->dbidev;
>>> +       priv->cfg = cfg;
>>> +
>>> +       dbi = &dbidev->dbi;
>>> +       drm = &dbidev->drm;
>>> +
>>> +       dbi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
>>> +       if (IS_ERR(dbi->reset))
>>> +               return dev_err_probe(dev, PTR_ERR(dbi->reset),
>>> "Failed to get reset GPIO\n");
>>> +
>>> +       dc = devm_gpiod_get_optional(dev, "dc", GPIOD_OUT_LOW);
>>> +       if (IS_ERR(dc))
>>> +               return dev_err_probe(dev, PTR_ERR(dc), "Failed to
>>> get D/C GPIO\n");
>>> +
>>> +       dbidev->backlight = devm_of_find_backlight(dev);
>>> +       if (IS_ERR(dbidev->backlight))
>>> +               return PTR_ERR(dbidev->backlight);
>>> +
>>> +       device_property_read_u32(dev, "rotation", &rotation);
>>> +
>>> +       ret = mipi_dbi_spi_init(spi, dbi, dc);
>>> +       if (ret)
>>> +               return ret;
>>> +
>>> +       if (cfg->write_only)
>>> +               dbi->read_commands = NULL;
>>> +
>>> +       ret = mipi_dbi_dev_init(dbidev, &simple_dbi_pipe_funcs,
>>> &cfg->mode,
>>> +                               rotation);
>>> +       if (ret)
>>> +               return ret;
>>> +
>>> +       drm_mode_config_reset(drm);
>>> +
>>> +       ret = drm_dev_register(drm, 0);
>>> +       if (ret)
>>> +               return ret;
>>> +
>>> +       spi_set_drvdata(spi, drm);
>>
>> AFAIK dev files are being created during drm_dev_register(). It's
>> probably safer to set the drvdata before.
> 
> Okay, thanks.
> 
>>
>>> +
>>> +       drm_fbdev_generic_setup(drm, 0);
>>> +
>>> +       return 0;
>>> +}
>>> +
>>> +static int simple_dbi_remove(struct spi_device *spi)
>>> +{
>>> +       struct drm_device *drm = spi_get_drvdata(spi);
>>> +
>>> +       drm_dev_unplug(drm);
>>> +       drm_atomic_helper_shutdown(drm);
>>> +
>>> +       return 0;
>>> +}
>>> +
>>> +static void simple_dbi_shutdown(struct spi_device *spi)
>>> +{
>>> +       drm_atomic_helper_shutdown(spi_get_drvdata(spi));
>>> +}
>>> +
>>> +static struct spi_driver simple_dbi_spi_driver = {
>>> +       .driver = {
>>> +               .name = "simple-dbi",
>>> +               .of_match_table = simple_dbi_of_match,
>>> +       },
>>> +       .probe = simple_dbi_probe,
>>> +       .remove = simple_dbi_remove,
>>> +       .shutdown = simple_dbi_shutdown,
>>> +};
>>> +module_spi_driver(simple_dbi_spi_driver);
>>> +
>>> +MODULE_DESCRIPTION("Simple DBI panel DRM driver");
>>> +MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>");
>>> +MODULE_LICENSE("GPL");
>>>
>>
>> Trailing blank line. (?)
> 
> Ah I do not know what happened, I just `git format-patch` and then `git
> send-email`.
> 
> At least I have no trailing blank line in the file inside patch :-)

No problem. Could have been my email client.

After you cleaned up the patch as you outlined above, you can add

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>

to the patch. I don't have much insight into the MIPI code. Maybe ask 
for someone else's review as well.

Best regards
Thomas

> 
>>
>> Best regards
>> Thomas
>>
> 
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer


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Re: [PATCH 1/4] dt-bindings: vendor-prefixes: add Zhishengxin

[Rob Herring]

On Mon, 02 Aug 2021 14:35:35 +0800, Icenowy Zheng wrote:
> Shenzhen Zhishengxin Technology Co., Ltd. is a LCD module supplier.
> 
> Add vendor prefix for it.
> 
> Signed-off-by: Icenowy Zheng <icenowy@sipeed.com>
> ---
>  Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
>  1 file changed, 2 insertions(+)
> 

Acked-by: Rob Herring <robh@kernel.org>

Re: [PATCH 2/4] dt-bindings: display: add binding for simple-dbi panels

[Rob Herring]

On Mon, Aug 02, 2021 at 02:35:36PM +0800, Icenowy Zheng wrote:
> As we're going to introduce a driver for MIPI DBI panels that need only
> standard MIPI-DCS commands to initialize (usually because the controller
> has some configuration pre-programmed), add a DT binding file for it,
> which now includes only one DBI Type C Option 3 panel, ZSX154-B1206.
> 
> Signed-off-by: Icenowy Zheng <icenowy@sipeed.com>
> ---
>  .../bindings/display/simple-dbi.yaml          | 72 +++++++++++++++++++
>  1 file changed, 72 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/simple-dbi.yaml
> 
> diff --git a/Documentation/devicetree/bindings/display/simple-dbi.yaml b/Documentation/devicetree/bindings/display/simple-dbi.yaml
> new file mode 100644
> index 000000000000..f49b0fda0935
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/simple-dbi.yaml
> @@ -0,0 +1,72 @@
> +# SPDX-License-Identifier: GPL-2.0-only

checkpatch.pl will tell you this should be dual licensed.