2023-05-19 14:32:11

by Paulo Pavacic

[permalink] [raw]
Subject: [PATCH 2/2] drm/panel-fannal-c3004: Add fannal c3004 DSI panel


Fannal C3004 is a 480x800 display made by fannal that requires
DCS initialization sequences.

Signed-off-by: Paulo Pavacic <[email protected]>
---
v2 changelog:
- renamed from panel-mipi-dsi-bringup
- only one MAINTAINER e-mail
---
MAINTAINERS | 1 +
drivers/gpu/drm/panel/Kconfig | 11 +
drivers/gpu/drm/panel/Makefile | 1 +
drivers/gpu/drm/panel/panel-fannal-c3004.c | 405 +++++++++++++++++++++
4 files changed, 418 insertions(+)
create mode 100644 drivers/gpu/drm/panel/panel-fannal-c3004.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 62374c8424b9..93fc1ae6832f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6432,6 +6432,7 @@ M: Paulo Pavacic <[email protected]>
S: Maintained
C: matrix:r/mipi-dsi-bringup:matrix.org
F: Documentation/devicetree/bindings/display/panel/panel-fannal,c3004.yaml
+F: drivers/gpu/drm/panel/panel-fannal-c3004.c

DRM DRIVER FOR FARADAY TVE200 TV ENCODER
M: Linus Walleij <[email protected]>
diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 2b9d6db7860b..a1041c1e6bf6 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -144,6 +144,17 @@ config DRM_PANEL_ELIDA_KD35T133
KD35T133 controller for 320x480 LCD panels with MIPI-DSI
system interfaces.

+config DRM_PANEL_FANNAL_C3004
+ tristate "Fannal C3004 panel"
+ depends on OF
+ depends on DRM_MIPI_DSI
+ help
+ Say Y here if you want to enable support for the Fannal C3004
+ 2-lane 480x800 MIPI DSI panel which requires initialization
+ sequence.
+
+ If M is selected the module will be called panel-fannal-c3004.
+
config DRM_PANEL_FEIXIN_K101_IM2BA02
tristate "Feixin K101 IM2BA02 panel"
depends on OF
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index ff169781e82d..13c0f00038b5 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_DRM_PANEL_SIMPLE) += panel-simple.o
obj-$(CONFIG_DRM_PANEL_EDP) += panel-edp.o
obj-$(CONFIG_DRM_PANEL_EBBG_FT8719) += panel-ebbg-ft8719.o
obj-$(CONFIG_DRM_PANEL_ELIDA_KD35T133) += panel-elida-kd35t133.o
+obj-$(CONFIG_DRM_PANEL_FANNAL_C3004) += panel-fannal-c3004.o
obj-$(CONFIG_DRM_PANEL_FEIXIN_K101_IM2BA02) += panel-feixin-k101-im2ba02.o
obj-$(CONFIG_DRM_PANEL_FEIYANG_FY07024DI26A30D) += panel-feiyang-fy07024di26a30d.o
obj-$(CONFIG_DRM_PANEL_HIMAX_HX8394) += panel-himax-hx8394.o
diff --git a/drivers/gpu/drm/panel/panel-fannal-c3004.c b/drivers/gpu/drm/panel/panel-fannal-c3004.c
new file mode 100644
index 000000000000..decbd0c59093
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-fannal-c3004.c
@@ -0,0 +1,405 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MIPI DSI driver for Fannal C3004.
+ * Copyright (C) 2023, Zenitel
+ * Author: Paulo Pavacic <[email protected]>
+ */
+
+// ↓ include headers, static values, static functions ↓
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/media-bus-format.h>
+
+#include <video/mipi_display.h>
+#include <video/of_videomode.h>
+#include <video/videomode.h>
+
+#include <drm/drm_crtc.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_panel.h>
+
+static const struct fann_panel_info fann_c3004_panel_info;
+
+struct fann_panel_info {
+ const struct drm_display_mode *display_mode;
+ u32 num_of_dsi_lanes;
+ u32 mipi_dsi_format;
+ u32 mipi_dsi_mode_flags;
+ u32 bus_flags;
+ u32 video_mode;
+ void (*panel_enable_function)(struct mipi_dsi_device *dsi);
+};
+
+struct fann_panel_data {
+ const struct fann_panel_info *panel_info;
+ struct drm_panel panel;
+ struct gpio_desc *reset;
+};
+
+static struct fann_panel_data *
+get_fann_panel_data_from_panel(struct drm_panel *panel)
+{
+ return container_of(panel, struct fann_panel_data, panel);
+}
+
+static const struct fann_panel_info *
+get_fann_panel_info_from_panel(struct drm_panel *panel)
+{
+ return get_fann_panel_data_from_panel(panel)->panel_info;
+}
+
+enum FANN_VIDEO_MODES_ENUM {
+ FANN_BURST,
+ FANN_SYNC_EVENT,
+ FANN_SYNC_PULSE,
+ FANN_COMMAND,
+};
+
+static const u32 FANN_VIDEO_MODES[] = {
+ MIPI_DSI_MODE_VIDEO_BURST | MIPI_DSI_MODE_VIDEO, //BURST
+ MIPI_DSI_MODE_VIDEO, //SYNC_EVENT
+ MIPI_DSI_MODE_VIDEO_SYNC_PULSE | MIPI_DSI_MODE_VIDEO, //SYNC_PULSE
+ MIPI_DSI_CLOCK_NON_CONTINUOUS | MIPI_DSI_MODE_VSYNC_FLUSH //COMMAND MODE
+};
+
+//macro for writing to DSI
+#define WRITE_DSI(dsi, seq...) \
+ { \
+ const u8 d[] = { seq }; \
+ int ret = mipi_dsi_generic_write(dsi, d, ARRAY_SIZE(d)); \
+ if (ret < 0) { \
+ dev_err(&dsi->dev, \
+ "Error (%d) occurred while trying to" \
+ " write MIPI DSI command: %s (decimal value)\n", \
+ ret, d); \
+ } \
+ }
+
+// ↑ include headers, static values, static functions ↑
+// ↓ INTERACTION whole section: panel specific values, add panel as is shown ↓
+
+/**
+ * @brief Adding new panel
+ * Includes but isn't limited to following steps:
+ * 1. define new `fann__yourpanel_display_mode` with correct timings
+ * 2. define new `fann_panel_yourpanel_enable_function`
+ * 3. glue everything with fann_yourpanel_panel_info and set that srtucts values
+ * 4. add .compatible = "you,yourpanel", .data = &fann_yourpanel_panel_info }
+ */
+
+static const u32 fann_bus_formats[] = {
+ MEDIA_BUS_FMT_RGB888_1X24,
+};
+
+// resolution 480p x 800p, 56mmx93mm
+static const struct drm_display_mode fann_c3004_display_mode = {
+ .clock = 27000,
+ .hdisplay = 480, // display height pixels
+ .hsync_start = 480 + 30, // hdisplay + HBP
+ .hsync_end = 480 + 30 + 8, // hdisplay + HBP + HSync
+ .htotal = 480 + 30 + 8 + 30, // hdisplay + HBP + HSync + HFP
+ .vdisplay = 800, // display width pixels
+ .vsync_start = 800 + 20, // vdisplay + VBP
+ .vsync_end = 800 + 20 + 8, // vdisplay + VBP + VSync
+ .vtotal = 800 + 20 + 8 + 20, // vdisplay + VBP + VSync + VFP
+ .width_mm = 93,
+ .height_mm = 56,
+ .flags = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
+};
+
+static void fann_panel_fannal_c3004_enable_function(struct mipi_dsi_device *dsi)
+{
+ WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x13);
+ WRITE_DSI(dsi, 0xEF, 0x08);
+
+ WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x10);
+ WRITE_DSI(dsi, 0xC0, 0x63, 0x00);
+ WRITE_DSI(dsi, 0xC1, 0x0A, 0x0C);
+ WRITE_DSI(dsi, 0xC2, 0x31, 0x08);
+ WRITE_DSI(dsi, 0xCC, 0x18);
+
+ WRITE_DSI(dsi, 0xB0, 0x00, 0x08, 0x10, 0x0E, 0x11, 0x07, 0x08, 0x08,
+ 0x08, 0x25, 0x04, 0x12, 0x0F, 0x2C, 0x30, 0x1F);
+ WRITE_DSI(dsi, 0xB1, 0x00, 0x11, 0x18, 0x0C, 0x10, 0x05, 0x07, 0x09,
+ 0x08, 0x24, 0x04, 0x11, 0x10, 0x2B, 0x30, 0x1F);
+
+ WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x11);
+ WRITE_DSI(dsi, 0xB0, 0x4D);
+ WRITE_DSI(dsi, 0xB1, 0x39);
+ WRITE_DSI(dsi, 0xB2, 0x87);
+ WRITE_DSI(dsi, 0xB3, 0x80);
+ WRITE_DSI(dsi, 0xB5, 0x47);
+ WRITE_DSI(dsi, 0xB7, 0x8A);
+ WRITE_DSI(dsi, 0xB8, 0x20);
+ WRITE_DSI(dsi, 0xB9, 0x10, 0x13);
+ WRITE_DSI(dsi, 0xC1, 0x78);
+ WRITE_DSI(dsi, 0xC2, 0x78);
+ WRITE_DSI(dsi, 0xD0, 0x88);
+
+ //PANEL
+ WRITE_DSI(dsi, 0xE0, 0x00, 0x00, 0x02);
+ WRITE_DSI(dsi, 0xE1, 0x04, 0x00, 0x00, 0x00, 0x05, 0x00, 0x00, 0x00,
+ 0x00, 0x20, 0x20);
+ WRITE_DSI(dsi, 0xE2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00);
+ WRITE_DSI(dsi, 0xE3, 0x00, 0x00, 0x33, 0x00);
+ WRITE_DSI(dsi, 0xE4, 0x22, 0x00);
+ WRITE_DSI(dsi, 0xE5, 0x04, 0x34, 0xAA, 0xAA, 0x06, 0x34, 0xAA, 0xAA,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
+ WRITE_DSI(dsi, 0xE6, 0x00, 0x00, 0x33, 0x00);
+ WRITE_DSI(dsi, 0xE7, 0x22, 0x00);
+ WRITE_DSI(dsi, 0xE8, 0x05, 0x34, 0xAA, 0xAA, 0x07, 0x34, 0xAA, 0xAA,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
+ WRITE_DSI(dsi, 0xEB, 0x02, 0x00, 0x40, 0x40, 0x00, 0x00, 0x00);
+ WRITE_DSI(dsi, 0xEC, 0x00, 0x00);
+ WRITE_DSI(dsi, 0xED, 0xFA, 0x45, 0x0B, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xB0, 0x54, 0xAF);
+ WRITE_DSI(dsi, 0xEF, 0x10, 0x0D, 0x04, 0x08, 0x3F, 0x1F);
+
+ WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x13);
+ WRITE_DSI(dsi, 0xE8, 0x00, 0x0E);
+
+ WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x00);
+ WRITE_DSI(dsi, 0x11); //MIPI_DCS_EXIT_SLEEP_MODE
+
+ msleep(600);
+
+ WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x13);
+ WRITE_DSI(dsi, 0xE8, 0x00, 0x0C);
+ msleep(50);
+ WRITE_DSI(dsi, 0xE8, 0x00, 0x00);
+
+ WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x00);
+ WRITE_DSI(dsi, 0x29); //MIPI_DCS_SET_DISPLAY_ON
+ msleep(100);
+}
+
+static const struct fann_panel_info fann_c3004_panel_info = {
+ .display_mode = &fann_c3004_display_mode,
+ .num_of_dsi_lanes = 2, //how many wires are connected to the panel
+ .video_mode = FANN_VIDEO_MODES[FANN_SYNC_PULSE],
+ .mipi_dsi_format = MIPI_DSI_FMT_RGB888,
+ .mipi_dsi_mode_flags =
+ MIPI_DSI_CLOCK_NON_CONTINUOUS | MIPI_DSI_MODE_VSYNC_FLUSH |
+ MIPI_DSI_MODE_VIDEO_HSE | MIPI_DSI_MODE_NO_EOT_PACKET,
+ .bus_flags = DRM_BUS_FLAG_DE_LOW | DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,
+ .panel_enable_function = &fann_panel_fannal_c3004_enable_function
+};
+
+// ↑ INTERACTION: panel specific values, add panel as is show in the example ↑
+// ↓ remove driver/cleanup ↓
+static void fann_panel_remove(struct mipi_dsi_device *dsi)
+{
+ struct fann_panel_data *panel_data = mipi_dsi_get_drvdata(dsi);
+ struct device *dev = &dsi->dev;
+ int ret;
+
+ ret = mipi_dsi_detach(dsi);
+ if (ret)
+ dev_err(dev, "error: disable: mipi detach (%d)\n", ret);
+
+ drm_panel_remove(&panel_data->panel);
+}
+
+static int fann_panel_disable(struct drm_panel *panel)
+{
+ struct mipi_dsi_device *dsi = to_mipi_dsi_device(panel->dev);
+ struct device *dev = panel->dev;
+ int ret;
+
+ dsi->mode_flags |= MIPI_DSI_MODE_LPM;
+
+ ret = mipi_dsi_dcs_set_display_off(dsi);
+ if (ret < 0) {
+ dev_err(dev, "error: disable: turn display OFF (%d)\n", ret);
+ return ret;
+ }
+
+ usleep_range(5000, 10000);
+
+ ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
+ if (ret < 0) {
+ dev_err(dev, "error: disable: enter sleep mode (%d)\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int fann_panel_unprepare(struct drm_panel *panel)
+{
+ struct fann_panel_data *panel_data =
+ get_fann_panel_data_from_panel(panel);
+
+ if (panel_data->reset) {
+ gpiod_set_value_cansleep(panel_data->reset, 1);
+ usleep_range(15000, 17000);
+ gpiod_set_value_cansleep(panel_data->reset, 0);
+ }
+
+ return 0;
+}
+
+static void fann_panel_shutdown(struct mipi_dsi_device *dsi)
+{
+ struct fann_panel_data *panel_data = mipi_dsi_get_drvdata(dsi);
+
+ fann_panel_disable(&panel_data->panel);
+ fann_panel_unprepare(&panel_data->panel);
+}
+
+// ↑ remove driver/cleanup ↑
+// ↓ probe/create functions ↓
+
+static int fann_panel_get_modes(struct drm_panel *panel,
+ struct drm_connector *connector)
+{
+ struct drm_display_mode *mode;
+ const struct fann_panel_info *panel_info =
+ get_fann_panel_info_from_panel(panel);
+ const struct drm_display_mode *panel_display_mode =
+ panel_info->display_mode;
+
+ mode = drm_mode_duplicate(connector->dev, panel_display_mode);
+ if (!mode) {
+ dev_err(panel->dev, "error: get_modes: add drm mode %ux%u@%u\n",
+ panel_display_mode->hdisplay,
+ panel_display_mode->vdisplay,
+ drm_mode_vrefresh(panel_display_mode));
+ return -ENOMEM;
+ }
+
+ drm_mode_set_name(mode);
+ mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
+ drm_mode_probed_add(connector, mode);
+
+ connector->display_info.width_mm = mode->width_mm;
+ connector->display_info.height_mm = mode->height_mm;
+ connector->display_info.bus_flags = panel_info->bus_flags;
+
+ drm_display_info_set_bus_formats(&connector->display_info,
+ fann_bus_formats,
+ ARRAY_SIZE(fann_bus_formats));
+ return 1;
+}
+
+static const struct of_device_id fann_of_match[] = {
+ { .compatible = "fannal,c3004", .data = &fann_c3004_panel_info },
+ { /* sentinel */ }
+};
+
+static int fann_panel_enable(struct drm_panel *panel)
+{
+ struct mipi_dsi_device *dsi = to_mipi_dsi_device(panel->dev);
+ const struct fann_panel_info *panel_info =
+ get_fann_panel_info_from_panel(panel);
+ panel_info->panel_enable_function(dsi);
+
+ return 0;
+}
+
+static int fann_panel_prepare(struct drm_panel *panel)
+{
+ struct fann_panel_data *panel_data =
+ get_fann_panel_data_from_panel(panel);
+
+ /* At lest 10ms needed between power-on and reset-out as RM specifies */
+ usleep_range(10000, 12000);
+
+ if (panel_data->reset) {
+ gpiod_set_value_cansleep(panel_data->reset, 0);
+ /*
+ * 50ms delay after reset-out, as per manufacturer initalization
+ * sequence.
+ */
+ msleep(50);
+ }
+
+ return 0;
+}
+
+static const struct drm_panel_funcs fann_panel_funcs = {
+ .prepare = fann_panel_prepare,
+ .unprepare = fann_panel_unprepare,
+ .enable = fann_panel_enable,
+ .disable = fann_panel_disable,
+ .get_modes = fann_panel_get_modes,
+};
+
+static int fann_panel_probe(struct mipi_dsi_device *dsi)
+{
+ struct device *dev = &dsi->dev;
+ const struct of_device_id *of_id = of_match_device(fann_of_match, dev);
+ const struct fann_panel_info *panel_info = of_id->data;
+ struct fann_panel_data *panel_data;
+ int ret;
+
+ dev_notice(dev, "probe driver called\n");
+ if (!panel_info) {
+ dev_err(dev, "error: probe: get panel_data!\n");
+ return -ENODEV;
+ }
+
+ panel_data = devm_kzalloc(&dsi->dev, sizeof(*panel_data), GFP_KERNEL);
+
+ if (!panel_data)
+ return -ENOMEM;
+
+ panel_data->panel_info = panel_info;
+ panel_data->reset = devm_gpiod_get_optional(
+ dev, "reset", GPIOD_OUT_LOW | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
+
+ if (IS_ERR(panel_data->reset)) {
+ ret = PTR_ERR(panel_data->reset);
+ dev_err(dev,
+ "error: probe: get reset GPIO: (%d) Check the fdt\n",
+ ret);
+ return ret;
+ }
+
+ mipi_dsi_set_drvdata(dsi, panel_data);
+
+ dsi->format = panel_info->mipi_dsi_format;
+ dsi->mode_flags = panel_info->mipi_dsi_mode_flags |
+ panel_info->video_mode;
+ dsi->lanes = panel_info->num_of_dsi_lanes;
+
+ gpiod_set_value_cansleep(panel_data->reset, 1);
+
+ drm_panel_init(&panel_data->panel, dev, &fann_panel_funcs,
+ DRM_MODE_CONNECTOR_DSI);
+ dev_set_drvdata(dev, panel_data);
+
+ drm_panel_add(&panel_data->panel);
+
+ ret = mipi_dsi_attach(dsi);
+ if (ret) {
+ drm_panel_remove(&panel_data->panel);
+ dev_err(dev, "error: probe fail: can't attach mipi_dsi!\n");
+ } else
+ dev_notice(dev, "probe driver success. Good job!\n");
+
+ return ret;
+}
+
+// ↑ probe/create functions ↑
+// ↓ generic driver stuff ↓
+
+static struct mipi_dsi_driver fann_panel_driver = {
+ .driver = {
+ .name = "panel-fannal-c3004",
+ .of_match_table = fann_of_match,
+ },
+ .probe = fann_panel_probe,
+ .remove = fann_panel_remove,
+ .shutdown = fann_panel_shutdown,
+};
+
+module_mipi_dsi_driver(fann_panel_driver);
+
+MODULE_AUTHOR("Paulo Pavacic <[email protected]>");
+MODULE_DESCRIPTION("Fannal C3004 panel driver");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(of, fann_of_match);
--
2.40.1



2023-05-22 09:01:52

by Neil Armstrong

[permalink] [raw]
Subject: Re: [PATCH 2/2] drm/panel-fannal-c3004: Add fannal c3004 DSI panel

Hi,

On 19/05/2023 16:24, Paulo Pavacic wrote:
>
> Fannal C3004 is a 480x800 display made by fannal that requires
> DCS initialization sequences.
>
> Signed-off-by: Paulo Pavacic <[email protected]>
> ---
> v2 changelog:
> - renamed from panel-mipi-dsi-bringup
> - only one MAINTAINER e-mail
> ---
> MAINTAINERS | 1 +
> drivers/gpu/drm/panel/Kconfig | 11 +
> drivers/gpu/drm/panel/Makefile | 1 +
> drivers/gpu/drm/panel/panel-fannal-c3004.c | 405 +++++++++++++++++++++
> 4 files changed, 418 insertions(+)
> create mode 100644 drivers/gpu/drm/panel/panel-fannal-c3004.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 62374c8424b9..93fc1ae6832f 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -6432,6 +6432,7 @@ M: Paulo Pavacic <[email protected]>
> S: Maintained
> C: matrix:r/mipi-dsi-bringup:matrix.org
> F: Documentation/devicetree/bindings/display/panel/panel-fannal,c3004.yaml
> +F: drivers/gpu/drm/panel/panel-fannal-c3004.c
>
> DRM DRIVER FOR FARADAY TVE200 TV ENCODER
> M: Linus Walleij <[email protected]>
> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
> index 2b9d6db7860b..a1041c1e6bf6 100644
> --- a/drivers/gpu/drm/panel/Kconfig
> +++ b/drivers/gpu/drm/panel/Kconfig
> @@ -144,6 +144,17 @@ config DRM_PANEL_ELIDA_KD35T133
> KD35T133 controller for 320x480 LCD panels with MIPI-DSI
> system interfaces.
>
> +config DRM_PANEL_FANNAL_C3004
> + tristate "Fannal C3004 panel"
> + depends on OF
> + depends on DRM_MIPI_DSI
> + help
> + Say Y here if you want to enable support for the Fannal C3004
> + 2-lane 480x800 MIPI DSI panel which requires initialization
> + sequence.
> +
> + If M is selected the module will be called panel-fannal-c3004.
> +
> config DRM_PANEL_FEIXIN_K101_IM2BA02
> tristate "Feixin K101 IM2BA02 panel"
> depends on OF
> diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
> index ff169781e82d..13c0f00038b5 100644
> --- a/drivers/gpu/drm/panel/Makefile
> +++ b/drivers/gpu/drm/panel/Makefile
> @@ -12,6 +12,7 @@ obj-$(CONFIG_DRM_PANEL_SIMPLE) += panel-simple.o
> obj-$(CONFIG_DRM_PANEL_EDP) += panel-edp.o
> obj-$(CONFIG_DRM_PANEL_EBBG_FT8719) += panel-ebbg-ft8719.o
> obj-$(CONFIG_DRM_PANEL_ELIDA_KD35T133) += panel-elida-kd35t133.o
> +obj-$(CONFIG_DRM_PANEL_FANNAL_C3004) += panel-fannal-c3004.o
> obj-$(CONFIG_DRM_PANEL_FEIXIN_K101_IM2BA02) += panel-feixin-k101-im2ba02.o
> obj-$(CONFIG_DRM_PANEL_FEIYANG_FY07024DI26A30D) += panel-feiyang-fy07024di26a30d.o
> obj-$(CONFIG_DRM_PANEL_HIMAX_HX8394) += panel-himax-hx8394.o
> diff --git a/drivers/gpu/drm/panel/panel-fannal-c3004.c b/drivers/gpu/drm/panel/panel-fannal-c3004.c
> new file mode 100644
> index 000000000000..decbd0c59093
> --- /dev/null
> +++ b/drivers/gpu/drm/panel/panel-fannal-c3004.c
> @@ -0,0 +1,405 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * MIPI DSI driver for Fannal C3004.
> + * Copyright (C) 2023, Zenitel
> + * Author: Paulo Pavacic <[email protected]>
> + */
> +
> +// ↓ include headers, static values, static functions ↓

This comment is unneeded, please remove it

> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/media-bus-format.h>
> +
> +#include <video/mipi_display.h>
> +#include <video/of_videomode.h>
> +#include <video/videomode.h>
> +
> +#include <drm/drm_crtc.h>
> +#include <drm/drm_mipi_dsi.h>
> +#include <drm/drm_panel.h>
> +
> +static const struct fann_panel_info fann_c3004_panel_info;

Please use fannal everywhere instead of fann

> +
> +struct fann_panel_info {
> + const struct drm_display_mode *display_mode;
> + u32 num_of_dsi_lanes;
> + u32 mipi_dsi_format;
> + u32 mipi_dsi_mode_flags;
> + u32 bus_flags;
> + u32 video_mode;
> + void (*panel_enable_function)(struct mipi_dsi_device *dsi);
> +};
> +
> +struct fann_panel_data {
> + const struct fann_panel_info *panel_info;
> + struct drm_panel panel;
> + struct gpio_desc *reset;
> +};
> +
> +static struct fann_panel_data *
> +get_fann_panel_data_from_panel(struct drm_panel *panel)
> +{
> + return container_of(panel, struct fann_panel_data, panel);
> +}
> +
> +static const struct fann_panel_info *
> +get_fann_panel_info_from_panel(struct drm_panel *panel)
> +{
> + return get_fann_panel_data_from_panel(panel)->panel_info;
> +}
> +
> +enum FANN_VIDEO_MODES_ENUM {
> + FANN_BURST,
> + FANN_SYNC_EVENT,
> + FANN_SYNC_PULSE,
> + FANN_COMMAND,
> +};
> +
> +static const u32 FANN_VIDEO_MODES[] = {
> + MIPI_DSI_MODE_VIDEO_BURST | MIPI_DSI_MODE_VIDEO, //BURST
> + MIPI_DSI_MODE_VIDEO, //SYNC_EVENT
> + MIPI_DSI_MODE_VIDEO_SYNC_PULSE | MIPI_DSI_MODE_VIDEO, //SYNC_PULSE
> + MIPI_DSI_CLOCK_NON_CONTINUOUS | MIPI_DSI_MODE_VSYNC_FLUSH //COMMAND MODE
> +};

Do not use this, please use "MIPI_DSI_MODE_VIDEO_SYNC_PULSE | MIPI_DSI_MODE_VIDEO" directly instead
of this table and enums.

> +
> +//macro for writing to DSI
> +#define WRITE_DSI(dsi, seq...) \
> + { \
> + const u8 d[] = { seq }; \
> + int ret = mipi_dsi_generic_write(dsi, d, ARRAY_SIZE(d)); \
> + if (ret < 0) { \
> + dev_err(&dsi->dev, \
> + "Error (%d) occurred while trying to" \
> + " write MIPI DSI command: %s (decimal value)\n", \
> + ret, d); \
> + } \
> + }

Please use mipi_dsi_generic_write_seq() instead of this macro.

> +
> +// ↑ include headers, static values, static functions ↑
> +// ↓ INTERACTION whole section: panel specific values, add panel as is shown ↓

Remove all those comments

> +
> +/**
> + * @brief Adding new panel
> + * Includes but isn't limited to following steps:
> + * 1. define new `fann__yourpanel_display_mode` with correct timings
> + * 2. define new `fann_panel_yourpanel_enable_function`
> + * 3. glue everything with fann_yourpanel_panel_info and set that srtucts values
> + * 4. add .compatible = "you,yourpanel", .data = &fann_yourpanel_panel_info }
> + */
> +
> +static const u32 fann_bus_formats[] = {
> + MEDIA_BUS_FMT_RGB888_1X24,
> +};
> +
> +// resolution 480p x 800p, 56mmx93mm
> +static const struct drm_display_mode fann_c3004_display_mode = {
> + .clock = 27000,
> + .hdisplay = 480, // display height pixels
> + .hsync_start = 480 + 30, // hdisplay + HBP
> + .hsync_end = 480 + 30 + 8, // hdisplay + HBP + HSync
> + .htotal = 480 + 30 + 8 + 30, // hdisplay + HBP + HSync + HFP
> + .vdisplay = 800, // display width pixels
> + .vsync_start = 800 + 20, // vdisplay + VBP
> + .vsync_end = 800 + 20 + 8, // vdisplay + VBP + VSync
> + .vtotal = 800 + 20 + 8 + 20, // vdisplay + VBP + VSync + VFP
> + .width_mm = 93,
> + .height_mm = 56,
> + .flags = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
> +};
> +
> +static void fann_panel_fannal_c3004_enable_function(struct mipi_dsi_device *dsi)
> +{
> + WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x13);
> + WRITE_DSI(dsi, 0xEF, 0x08);
> +
> + WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x10);
> + WRITE_DSI(dsi, 0xC0, 0x63, 0x00);
> + WRITE_DSI(dsi, 0xC1, 0x0A, 0x0C);
> + WRITE_DSI(dsi, 0xC2, 0x31, 0x08);
> + WRITE_DSI(dsi, 0xCC, 0x18);
> +
> + WRITE_DSI(dsi, 0xB0, 0x00, 0x08, 0x10, 0x0E, 0x11, 0x07, 0x08, 0x08,
> + 0x08, 0x25, 0x04, 0x12, 0x0F, 0x2C, 0x30, 0x1F);
> + WRITE_DSI(dsi, 0xB1, 0x00, 0x11, 0x18, 0x0C, 0x10, 0x05, 0x07, 0x09,
> + 0x08, 0x24, 0x04, 0x11, 0x10, 0x2B, 0x30, 0x1F);
> +
> + WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x11);
> + WRITE_DSI(dsi, 0xB0, 0x4D);
> + WRITE_DSI(dsi, 0xB1, 0x39);
> + WRITE_DSI(dsi, 0xB2, 0x87);
> + WRITE_DSI(dsi, 0xB3, 0x80);
> + WRITE_DSI(dsi, 0xB5, 0x47);
> + WRITE_DSI(dsi, 0xB7, 0x8A);
> + WRITE_DSI(dsi, 0xB8, 0x20);
> + WRITE_DSI(dsi, 0xB9, 0x10, 0x13);
> + WRITE_DSI(dsi, 0xC1, 0x78);
> + WRITE_DSI(dsi, 0xC2, 0x78);
> + WRITE_DSI(dsi, 0xD0, 0x88);
> +
> + //PANEL
> + WRITE_DSI(dsi, 0xE0, 0x00, 0x00, 0x02);
> + WRITE_DSI(dsi, 0xE1, 0x04, 0x00, 0x00, 0x00, 0x05, 0x00, 0x00, 0x00,
> + 0x00, 0x20, 0x20);
> + WRITE_DSI(dsi, 0xE2, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> + 0x00, 0x00, 0x00, 0x00, 0x00);
> + WRITE_DSI(dsi, 0xE3, 0x00, 0x00, 0x33, 0x00);
> + WRITE_DSI(dsi, 0xE4, 0x22, 0x00);
> + WRITE_DSI(dsi, 0xE5, 0x04, 0x34, 0xAA, 0xAA, 0x06, 0x34, 0xAA, 0xAA,
> + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
> + WRITE_DSI(dsi, 0xE6, 0x00, 0x00, 0x33, 0x00);
> + WRITE_DSI(dsi, 0xE7, 0x22, 0x00);
> + WRITE_DSI(dsi, 0xE8, 0x05, 0x34, 0xAA, 0xAA, 0x07, 0x34, 0xAA, 0xAA,
> + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
> + WRITE_DSI(dsi, 0xEB, 0x02, 0x00, 0x40, 0x40, 0x00, 0x00, 0x00);
> + WRITE_DSI(dsi, 0xEC, 0x00, 0x00);
> + WRITE_DSI(dsi, 0xED, 0xFA, 0x45, 0x0B, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
> + 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xB0, 0x54, 0xAF);
> + WRITE_DSI(dsi, 0xEF, 0x10, 0x0D, 0x04, 0x08, 0x3F, 0x1F);
> +
> + WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x13);
> + WRITE_DSI(dsi, 0xE8, 0x00, 0x0E);
> +
> + WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x00);
> + WRITE_DSI(dsi, 0x11); //MIPI_DCS_EXIT_SLEEP_MODE
> +
> + msleep(600);
> +
> + WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x13);
> + WRITE_DSI(dsi, 0xE8, 0x00, 0x0C);
> + msleep(50);
> + WRITE_DSI(dsi, 0xE8, 0x00, 0x00);
> +
> + WRITE_DSI(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x00);
> + WRITE_DSI(dsi, 0x29); //MIPI_DCS_SET_DISPLAY_ON
> + msleep(100);
> +}
> +
> +static const struct fann_panel_info fann_c3004_panel_info = {
> + .display_mode = &fann_c3004_display_mode,
> + .num_of_dsi_lanes = 2, //how many wires are connected to the panel
> + .video_mode = FANN_VIDEO_MODES[FANN_SYNC_PULSE],
> + .mipi_dsi_format = MIPI_DSI_FMT_RGB888,
> + .mipi_dsi_mode_flags =
> + MIPI_DSI_CLOCK_NON_CONTINUOUS | MIPI_DSI_MODE_VSYNC_FLUSH |
> + MIPI_DSI_MODE_VIDEO_HSE | MIPI_DSI_MODE_NO_EOT_PACKET,
> + .bus_flags = DRM_BUS_FLAG_DE_LOW | DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,
> + .panel_enable_function = &fann_panel_fannal_c3004_enable_function
> +};

If you handle a single panel, this isn't necessary and you should set all those
values into probe and panel ops

> +
> +// ↑ INTERACTION: panel specific values, add panel as is show in the example ↑
> +// ↓ remove driver/cleanup ↓
> +static void fann_panel_remove(struct mipi_dsi_device *dsi)
> +{
> + struct fann_panel_data *panel_data = mipi_dsi_get_drvdata(dsi);
> + struct device *dev = &dsi->dev;
> + int ret;
> +
> + ret = mipi_dsi_detach(dsi);
> + if (ret)
> + dev_err(dev, "error: disable: mipi detach (%d)\n", ret);
> +
> + drm_panel_remove(&panel_data->panel);
> +}
> +
> +static int fann_panel_disable(struct drm_panel *panel)
> +{
> + struct mipi_dsi_device *dsi = to_mipi_dsi_device(panel->dev);
> + struct device *dev = panel->dev;
> + int ret;
> +
> + dsi->mode_flags |= MIPI_DSI_MODE_LPM;
> +
> + ret = mipi_dsi_dcs_set_display_off(dsi);
> + if (ret < 0) {
> + dev_err(dev, "error: disable: turn display OFF (%d)\n", ret);
> + return ret;
> + }
> +
> + usleep_range(5000, 10000);
> +
> + ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
> + if (ret < 0) {
> + dev_err(dev, "error: disable: enter sleep mode (%d)\n", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int fann_panel_unprepare(struct drm_panel *panel)
> +{
> + struct fann_panel_data *panel_data =
> + get_fann_panel_data_from_panel(panel);
> +
> + if (panel_data->reset) {
> + gpiod_set_value_cansleep(panel_data->reset, 1);
> + usleep_range(15000, 17000);
> + gpiod_set_value_cansleep(panel_data->reset, 0);
> + }
> +
> + return 0;
> +}
> +
> +static void fann_panel_shutdown(struct mipi_dsi_device *dsi)
> +{
> + struct fann_panel_data *panel_data = mipi_dsi_get_drvdata(dsi);
> +
> + fann_panel_disable(&panel_data->panel);
> + fann_panel_unprepare(&panel_data->panel);
> +}
> +
> +// ↑ remove driver/cleanup ↑
> +// ↓ probe/create functions ↓
> +
> +static int fann_panel_get_modes(struct drm_panel *panel,
> + struct drm_connector *connector)
> +{
> + struct drm_display_mode *mode;
> + const struct fann_panel_info *panel_info =
> + get_fann_panel_info_from_panel(panel);
> + const struct drm_display_mode *panel_display_mode =
> + panel_info->display_mode;

Using this panel_display_mode makes it complex for nothing, please
directly use fann_c3004_display_mode here.

> +
> + mode = drm_mode_duplicate(connector->dev, panel_display_mode);
> + if (!mode) {
> + dev_err(panel->dev, "error: get_modes: add drm mode %ux%u@%u\n",
> + panel_display_mode->hdisplay,
> + panel_display_mode->vdisplay,
> + drm_mode_vrefresh(panel_display_mode));
> + return -ENOMEM;
> + }
> +
> + drm_mode_set_name(mode);
> + mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
> + drm_mode_probed_add(connector, mode);
> +
> + connector->display_info.width_mm = mode->width_mm;
> + connector->display_info.height_mm = mode->height_mm;
> + connector->display_info.bus_flags = panel_info->bus_flags;

Set the bus flasg directly here

> +
> + drm_display_info_set_bus_formats(&connector->display_info,
> + fann_bus_formats,
> + ARRAY_SIZE(fann_bus_formats)); > + return 1;
> +}
> +
> +static const struct of_device_id fann_of_match[] = {
> + { .compatible = "fannal,c3004", .data = &fann_c3004_panel_info },

Please introduce such data when you'll need to handle multiple panels,
for now it's mostly unnecessary code.

> + { /* sentinel */ }
> +};
> +
> +static int fann_panel_enable(struct drm_panel *panel)
> +{
> + struct mipi_dsi_device *dsi = to_mipi_dsi_device(panel->dev);
> + const struct fann_panel_info *panel_info =
> + get_fann_panel_info_from_panel(panel);
> + panel_info->panel_enable_function(dsi);
> +
> + return 0;
> +}
> +
> +static int fann_panel_prepare(struct drm_panel *panel)
> +{
> + struct fann_panel_data *panel_data =
> + get_fann_panel_data_from_panel(panel);
> +
> + /* At lest 10ms needed between power-on and reset-out as RM specifies */
> + usleep_range(10000, 12000);
> +
> + if (panel_data->reset) {
> + gpiod_set_value_cansleep(panel_data->reset, 0);
> + /*
> + * 50ms delay after reset-out, as per manufacturer initalization
> + * sequence.
> + */
> + msleep(50);
> + }
> +
> + return 0;
> +}
> +
> +static const struct drm_panel_funcs fann_panel_funcs = {
> + .prepare = fann_panel_prepare,
> + .unprepare = fann_panel_unprepare,
> + .enable = fann_panel_enable,
> + .disable = fann_panel_disable,
> + .get_modes = fann_panel_get_modes,
> +};
> +
> +static int fann_panel_probe(struct mipi_dsi_device *dsi)
> +{
> + struct device *dev = &dsi->dev;
> + const struct of_device_id *of_id = of_match_device(fann_of_match, dev);
> + const struct fann_panel_info *panel_info = of_id->data;
> + struct fann_panel_data *panel_data;
> + int ret;
> +
> + dev_notice(dev, "probe driver called\n");

Drop those prints.

> + if (!panel_info) {
> + dev_err(dev, "error: probe: get panel_data!\n");
> + return -ENODEV;
> + }
> +
> + panel_data = devm_kzalloc(&dsi->dev, sizeof(*panel_data), GFP_KERNEL);
> +
> + if (!panel_data)
> + return -ENOMEM;
> +
> + panel_data->panel_info = panel_info;
> + panel_data->reset = devm_gpiod_get_optional(
> + dev, "reset", GPIOD_OUT_LOW | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
> +
> + if (IS_ERR(panel_data->reset)) {
> + ret = PTR_ERR(panel_data->reset);
> + dev_err(dev,
> + "error: probe: get reset GPIO: (%d) Check the fdt\n",
> + ret);
> + return ret;
> + }
> +
> + mipi_dsi_set_drvdata(dsi, panel_data);
> +
> + dsi->format = panel_info->mipi_dsi_format;
> + dsi->mode_flags = panel_info->mipi_dsi_mode_flags |
> + panel_info->video_mode;
> + dsi->lanes = panel_info->num_of_dsi_lanes;
> +
> + gpiod_set_value_cansleep(panel_data->reset, 1);
> +
> + drm_panel_init(&panel_data->panel, dev, &fann_panel_funcs,
> + DRM_MODE_CONNECTOR_DSI);
> + dev_set_drvdata(dev, panel_data);
> +
> + drm_panel_add(&panel_data->panel);
> +
> + ret = mipi_dsi_attach(dsi);
> + if (ret) {
> + drm_panel_remove(&panel_data->panel);
> + dev_err(dev, "error: probe fail: can't attach mipi_dsi!\n");
> + } else
> + dev_notice(dev, "probe driver success. Good job!\n");
> +
> + return ret;
> +}
> +
> +// ↑ probe/create functions ↑
> +// ↓ generic driver stuff ↓
> +
> +static struct mipi_dsi_driver fann_panel_driver = {
> + .driver = {
> + .name = "panel-fannal-c3004",
> + .of_match_table = fann_of_match,
> + },
> + .probe = fann_panel_probe,
> + .remove = fann_panel_remove,
> + .shutdown = fann_panel_shutdown,
> +};
> +
> +module_mipi_dsi_driver(fann_panel_driver);
> +
> +MODULE_AUTHOR("Paulo Pavacic <[email protected]>");
> +MODULE_DESCRIPTION("Fannal C3004 panel driver");
> +MODULE_LICENSE("GPL");
> +MODULE_DEVICE_TABLE(of, fann_of_match);

I understand you want to write a clean panel driver for learning purposes,
but having unnecessary code isn't appreciated in the Linux codebase,
instead make a simple and readble driver with the state-of-the-art architecture
and helpers.


Thanks,
Neil


2023-05-23 17:45:12

by Linus Walleij

[permalink] [raw]
Subject: Re: [PATCH 2/2] drm/panel-fannal-c3004: Add fannal c3004 DSI panel

On Fri, May 19, 2023 at 4:25 PM Paulo Pavacic <[email protected]> wrote:

> +//macro for writing to DSI
> +#define WRITE_DSI(dsi, seq...) \
> + { \
> + const u8 d[] = { seq }; \
> + int ret = mipi_dsi_generic_write(dsi, d, ARRAY_SIZE(d)); \
> + if (ret < 0) { \
> + dev_err(&dsi->dev, \
> + "Error (%d) occurred while trying to" \
> + " write MIPI DSI command: %s (decimal value)\n", \
> + ret, d); \
> + } \
> + }

As said for the other patch, this reinvents mipi_dsi_dcs_write_seq()
so use that instead.

mipi_dsi_dcs_write_seq(dsi, 0xFF, 0x77, 0x01, 0x00, 0x00, 0x13);
etc.

Yours,
Linus Walleij