Re: [PATCH v3 3/5] drm: panel: Add Xingbangda XBD599 panel (ST7703 controller)

From: Samuel Holland
Date: Wed May 27 2020 - 23:31:56 EST

On 5/13/20 4:24 PM, Ondrej Jirman wrote:
> From: Icenowy Zheng <icenowy@xxxxxxx>
>
> Xingbangda XBD599 is a 5.99" 720x1440 MIPI-DSI IPS LCD panel made by
> Xingbangda, which is used on PinePhone final assembled phones.
>
> It is based on Sitronix ST7703 LCD controller.
>
> Add support for it.
>
> Signed-off-by: Icenowy Zheng <icenowy@xxxxxxx>
> Signed-off-by: Ondrej Jirman <megous@xxxxxxxxxx>
> ---
> drivers/gpu/drm/panel/Kconfig | 10 +
> drivers/gpu/drm/panel/Makefile | 1 +
> drivers/gpu/drm/panel/panel-sitronix-st7703.c | 386 ++++++++++++++++++
> 3 files changed, 397 insertions(+)
> create mode 100644 drivers/gpu/drm/panel/panel-sitronix-st7703.c
>
> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
> index 39055c1f0e2f..b7bc157b0612 100644
> --- a/drivers/gpu/drm/panel/Kconfig
> +++ b/drivers/gpu/drm/panel/Kconfig
> @@ -395,6 +395,16 @@ config DRM_PANEL_SITRONIX_ST7701
> ST7701 controller for 480X864 LCD panels with MIPI/RGB/SPI
> system interfaces.
>
> +config DRM_PANEL_SITRONIX_ST7703
> + tristate "Sitronix ST7703 panel driver"
> + depends on OF
> + depends on DRM_MIPI_DSI
> + depends on BACKLIGHT_CLASS_DEVICE
> + help
> + Say Y here if you want to enable support for the Sitronix
> + ST7703 controller for 720X1440 LCD panels with MIPI/RGB/SPI
> + system interfaces.
> +
> config DRM_PANEL_SITRONIX_ST7789V
> tristate "Sitronix ST7789V panel"
> depends on OF && SPI
> diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
> index de74f282c433..47f4789a8685 100644
> --- a/drivers/gpu/drm/panel/Makefile
> +++ b/drivers/gpu/drm/panel/Makefile
> @@ -41,6 +41,7 @@ obj-$(CONFIG_DRM_PANEL_SHARP_LQ101R1SX01) += panel-sharp-lq101r1sx01.o
> obj-$(CONFIG_DRM_PANEL_SHARP_LS037V7DW01) += panel-sharp-ls037v7dw01.o
> obj-$(CONFIG_DRM_PANEL_SHARP_LS043T1LE01) += panel-sharp-ls043t1le01.o
> obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7701) += panel-sitronix-st7701.o
> +obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7703) += panel-sitronix-st7703.o
> obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7789V) += panel-sitronix-st7789v.o
> obj-$(CONFIG_DRM_PANEL_SONY_ACX424AKP) += panel-sony-acx424akp.o
> obj-$(CONFIG_DRM_PANEL_SONY_ACX565AKM) += panel-sony-acx565akm.o
> diff --git a/drivers/gpu/drm/panel/panel-sitronix-st7703.c b/drivers/gpu/drm/panel/panel-sitronix-st7703.c
> new file mode 100644
> index 000000000000..092dd73c86d0
> --- /dev/null
> +++ b/drivers/gpu/drm/panel/panel-sitronix-st7703.c
> @@ -0,0 +1,386 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * DRM driver for Sitronix ST7703 MIPI DSI panel
> + *
> + * Copyright (C) 2020 Ondrej Jirman <megous@xxxxxxxxxx>
> + * Copyright (C) 2019-2020 Icenowy Zheng <icenowy@xxxxxxx>
> + *
> + * Based on panel-rocktech-jh057n00900.c, which is:
> + * Copyright (C) Purism SPC 2019
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include <drm/drm_mipi_dsi.h>
> +#include <drm/drm_modes.h>
> +#include <drm/drm_panel.h>
> +#include <drm/drm_print.h>
> +
> +/* Manufacturer specific Commands send via DSI */
> +#define ST7703_CMD_ALL_PIXEL_OFF 0x22
> +#define ST7703_CMD_ALL_PIXEL_ON 0x23
> +#define ST7703_CMD_SETDISP 0xB2
> +#define ST7703_CMD_SETRGBIF 0xB3
> +#define ST7703_CMD_SETCYC 0xB4
> +#define ST7703_CMD_SETBGP 0xB5
> +#define ST7703_CMD_SETVCOM 0xB6
> +#define ST7703_CMD_SETOTP 0xB7
> +#define ST7703_CMD_SETPOWER_EXT 0xB8
> +#define ST7703_CMD_SETEXTC 0xB9
> +#define ST7703_CMD_SETMIPI 0xBA
> +#define ST7703_CMD_SETVDC 0xBC
> +#define ST7703_CMD_SETSCR 0xC0
> +#define ST7703_CMD_SETPOWER 0xC1
> +#define ST7703_CMD_UNK_C6 0xC6
> +#define ST7703_CMD_SETPANEL 0xCC
> +#define ST7703_CMD_SETGAMMA 0xE0
> +#define ST7703_CMD_SETEQ 0xE3
> +#define ST7703_CMD_SETGIP1 0xE9
> +#define ST7703_CMD_SETGIP2 0xEA
> +
> +struct st7703_panel_desc {
> + const struct drm_display_mode *mode;
> + unsigned int lanes;
> + unsigned long flags;
> + enum mipi_dsi_pixel_format format;
> + const char *const *supply_names;
> + unsigned int num_supplies;
> +};
> +
> +struct st7703 {
> + struct device *dev;
> + struct drm_panel panel;
> + struct gpio_desc *reset_gpio;
> + struct regulator_bulk_data *supplies;
> + const struct st7703_panel_desc *desc;
> + bool prepared;
> +};
> +
> +static inline struct st7703 *panel_to_st7703(struct drm_panel *panel)
> +{
> + return container_of(panel, struct st7703, panel);
> +}
> +
> +#define dsi_dcs_write_seq(dsi, cmd, seq...) do { \
> + static const u8 d[] = { seq }; \
> + int ret; \
> + ret = mipi_dsi_dcs_write(dsi, cmd, d, ARRAY_SIZE(d)); \
> + if (ret < 0) \
> + return ret; \
> + } while (0)
> +
> +static int st7703_init_sequence(struct st7703 *ctx)
> +{
> + struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
> + struct device *dev = ctx->dev;
> + int ret;
> +
> + /*
> + * Init sequence was supplied by the panel vendor.
> + */
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETEXTC,
> + 0xF1, 0x12, 0x83);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETMIPI,
> + 0x33, 0x81, 0x05, 0xF9, 0x0E, 0x0E, 0x20, 0x00,
> + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x44, 0x25,
> + 0x00, 0x91, 0x0a, 0x00, 0x00, 0x02, 0x4F, 0x11,
> + 0x00, 0x00, 0x37);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETPOWER_EXT,
> + 0x25, 0x22, 0x20, 0x03);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETRGBIF,
> + 0x10, 0x10, 0x05, 0x05, 0x03, 0xFF, 0x00, 0x00,
> + 0x00, 0x00);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETSCR,
> + 0x73, 0x73, 0x50, 0x50, 0x00, 0xC0, 0x08, 0x70,
> + 0x00);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETVDC, 0x4E);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETPANEL, 0x0B);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETCYC, 0x80);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETDISP, 0xF0, 0x12, 0xF0);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETEQ,
> + 0x00, 0x00, 0x0B, 0x0B, 0x10, 0x10, 0x00, 0x00,
> + 0x00, 0x00, 0xFF, 0x00, 0xC0, 0x10);
> + dsi_dcs_write_seq(dsi, 0xC6, 0x01, 0x00, 0xFF, 0xFF, 0x00);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETPOWER,
> + 0x74, 0x00, 0x32, 0x32, 0x77, 0xF1, 0xFF, 0xFF,
> + 0xCC, 0xCC, 0x77, 0x77);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETBGP, 0x07, 0x07);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETVCOM, 0x2C, 0x2C);
> + dsi_dcs_write_seq(dsi, 0xBF, 0x02, 0x11, 0x00);
> +
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETGIP1,
> + 0x82, 0x10, 0x06, 0x05, 0xA2, 0x0A, 0xA5, 0x12,
> + 0x31, 0x23, 0x37, 0x83, 0x04, 0xBC, 0x27, 0x38,
> + 0x0C, 0x00, 0x03, 0x00, 0x00, 0x00, 0x0C, 0x00,
> + 0x03, 0x00, 0x00, 0x00, 0x75, 0x75, 0x31, 0x88,
> + 0x88, 0x88, 0x88, 0x88, 0x88, 0x13, 0x88, 0x64,
> + 0x64, 0x20, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88,
> + 0x02, 0x88, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETGIP2,
> + 0x02, 0x21, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> + 0x00, 0x00, 0x00, 0x00, 0x02, 0x46, 0x02, 0x88,
> + 0x88, 0x88, 0x88, 0x88, 0x88, 0x64, 0x88, 0x13,
> + 0x57, 0x13, 0x88, 0x88, 0x88, 0x88, 0x88, 0x88,
> + 0x75, 0x88, 0x23, 0x14, 0x00, 0x00, 0x02, 0x00,
> + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
> + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0x0A,
> + 0xA5, 0x00, 0x00, 0x00, 0x00);
> + dsi_dcs_write_seq(dsi, ST7703_CMD_SETGAMMA,
> + 0x00, 0x09, 0x0D, 0x23, 0x27, 0x3C, 0x41, 0x35,
> + 0x07, 0x0D, 0x0E, 0x12, 0x13, 0x10, 0x12, 0x12,
> + 0x18, 0x00, 0x09, 0x0D, 0x23, 0x27, 0x3C, 0x41,
> + 0x35, 0x07, 0x0D, 0x0E, 0x12, 0x13, 0x10, 0x12,
> + 0x12, 0x18);
> + msleep(20);
> +
> + ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dev, "Failed to exit sleep mode\n");
> + return ret;
> + }
> + msleep(250);
> +
> + ret = mipi_dsi_dcs_set_display_on(dsi);

Since you have the complementary call to mipi_dsi_dcs_set_display_off in
st7703_disable, I would suggest calling this from st7703_enable, after the call
to st7703_init_sequence. [but see below about moving all of this to prepare.]

> + if (ret)
> + return ret;
> + msleep(50);

This is the last step of the init sequence. According to table 8-1 of the
manual, T10 needs no delay. What is this delay for?

> +
> + DRM_DEV_DEBUG_DRIVER(dev, "Panel init sequence done\n");
> + return 0;
> +}
> +
> +static int st7703_prepare(struct drm_panel *panel)
> +{
> + struct st7703 *ctx = panel_to_st7703(panel);
> + int ret;
> +
> + if (ctx->prepared)
> + return 0;
> +
> + ret = regulator_bulk_enable(ctx->desc->num_supplies, ctx->supplies);
> + if (ret)
> + return ret;
> +
> + DRM_DEV_DEBUG_DRIVER(ctx->dev, "Resetting the panel\n");
> + gpiod_set_value_cansleep(ctx->reset_gpio, 1);
> + usleep_range(20, 40);
> + gpiod_set_value_cansleep(ctx->reset_gpio, 0);
> + msleep(20);
> +
> + ctx->prepared = true;
> +
> + return 0;
> +}
> +
> +static int st7703_enable(struct drm_panel *panel)
> +{
> + struct st7703 *ctx = panel_to_st7703(panel);
> + int ret;
> +
> + ret = st7703_init_sequence(ctx);

v1 had this function called from prepare, not enable. From reading the comments
in drm_panel.h, that seems to be the right place for it.

> + if (ret < 0) {
> + DRM_DEV_ERROR(ctx->dev, "Panel init sequence failed: %d\n",
> + ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int st7703_disable(struct drm_panel *panel)
> +{
> + struct st7703 *ctx = panel_to_st7703(panel);
> + struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
> +
> + return mipi_dsi_dcs_set_display_off(dsi);

The datasheet suggests in "5.6 Power on/off Sequence" that there also needs to
be a call to mipi_dsi_dcs_enter_sleep_mode() here.

> +}
> +
> +static int st7703_unprepare(struct drm_panel *panel)
> +{
> + struct st7703 *ctx = panel_to_st7703(panel);
> +
> + if (!ctx->prepared)
> + return 0;
> +
> + gpiod_set_value_cansleep(ctx->reset_gpio, 1);
> + regulator_bulk_disable(ctx->desc->num_supplies, ctx->supplies);
> + ctx->prepared = false;
> +
> + return 0;
> +}
> +
> +static int st7703_get_modes(struct drm_panel *panel,
> + struct drm_connector *connector)
> +{
> + struct st7703 *ctx = panel_to_st7703(panel);
> + struct drm_display_mode *mode;
> +
> + mode = drm_mode_duplicate(connector->dev, ctx->desc->mode);
> + if (!mode) {
> + DRM_DEV_ERROR(ctx->dev, "Failed to add mode\n");
> + return -ENOMEM;
> + }
> +
> + drm_mode_set_name(mode);
> +
> + mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;

This line...

> + connector->display_info.width_mm = mode->width_mm;
> + connector->display_info.height_mm = mode->height_mm;
> + drm_mode_probed_add(connector, mode);
> +
> + return 1;
> +}
> +
> +static const struct drm_panel_funcs st7703_drm_funcs = {
> + .prepare = st7703_prepare,
> + .enable = st7703_enable,
> + .disable = st7703_disable,
> + .unprepare = st7703_unprepare,
> + .get_modes = st7703_get_modes,
> +};
> +
> +static const struct drm_display_mode xbd599_mode = {
> + .hdisplay = 720,
> + .hsync_start = 720 + 40,
> + .hsync_end = 720 + 40 + 40,
> + .htotal = 720 + 40 + 40 + 40,
> + .vdisplay = 1440,
> + .vsync_start = 1440 + 18,
> + .vsync_end = 1440 + 18 + 10,
> + .vtotal = 1440 + 18 + 10 + 17,
> + .vrefresh = 60,
> + .clock = 69000,
> + .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
> +
> + .width_mm = 68,
> + .height_mm = 136,
> + .type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,

...duplicates this line. I'm not sure which is the better place to put it; panel
drivers seem evenly split. But it doesn't need to be in both places.

Cheers,
Samuel

> +};
> +
> +static const char * const xbd599_supply_names[] = {
> + "iovcc",
> + "vcc",
> +};
> +
> +static const struct st7703_panel_desc xbd599_desc = {
> + .mode = &xbd599_mode,
> + .lanes = 4,
> + .flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_SYNC_PULSE,
> + .format = MIPI_DSI_FMT_RGB888,
> + .supply_names = xbd599_supply_names,
> + .num_supplies = ARRAY_SIZE(xbd599_supply_names),
> +};
> +
> +static int st7703_probe(struct mipi_dsi_device *dsi)
> +{
> + const struct st7703_panel_desc *desc;
> + struct device *dev = &dsi->dev;
> + struct st7703 *ctx;
> + int i, ret;
> +
> + ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
> + if (!ctx)
> + return -ENOMEM;
> +
> + ctx->dev = dev;
> + ctx->desc = desc = of_device_get_match_data(dev);
> +
> + dsi->mode_flags = desc->flags;
> + dsi->format = desc->format;
> + dsi->lanes = desc->lanes;
> +
> + ctx->supplies = devm_kcalloc(&dsi->dev, desc->num_supplies,
> + sizeof(*ctx->supplies),
> + GFP_KERNEL);
> + if (!ctx->supplies)
> + return -ENOMEM;
> +
> + for (i = 0; i < desc->num_supplies; i++)
> + ctx->supplies[i].supply = desc->supply_names[i];
> +
> + ret = devm_regulator_bulk_get(&dsi->dev, desc->num_supplies,
> + ctx->supplies);
> + if (ret < 0)
> + return ret;
> +
> + ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
> + if (IS_ERR(ctx->reset_gpio)) {
> + DRM_DEV_ERROR(dev, "Can't get reset gpio\n");
> + return PTR_ERR(ctx->reset_gpio);
> + }
> +
> + mipi_dsi_set_drvdata(dsi, ctx);
> +
> + drm_panel_init(&ctx->panel, &dsi->dev, &st7703_drm_funcs,
> + DRM_MODE_CONNECTOR_DSI);
> +
> + ret = drm_panel_of_backlight(&ctx->panel);
> + if (ret)
> + return ret;
> +
> + drm_panel_add(&ctx->panel);
> +
> + ret = mipi_dsi_attach(dsi);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dev, "mipi_dsi_attach failed. Is host ready?\n");
> + drm_panel_remove(&ctx->panel);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void st7703_shutdown(struct mipi_dsi_device *dsi)
> +{
> + struct st7703 *ctx = mipi_dsi_get_drvdata(dsi);
> + int ret;
> +
> + ret = drm_panel_unprepare(&ctx->panel);
> + if (ret < 0)
> + DRM_DEV_ERROR(&dsi->dev, "Failed to unprepare panel: %d\n",
> + ret);
> +}
> +
> +static int st7703_remove(struct mipi_dsi_device *dsi)
> +{
> + struct st7703 *ctx = mipi_dsi_get_drvdata(dsi);
> + int ret;
> +
> + st7703_shutdown(dsi);
> +
> + ret = mipi_dsi_detach(dsi);
> + if (ret < 0)
> + DRM_DEV_ERROR(&dsi->dev, "Failed to detach from DSI host: %d\n",
> + ret);
> +
> + drm_panel_remove(&ctx->panel);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id st7703_of_match[] = {
> + { .compatible = "xingbangda,xbd599", .data = &xbd599_desc },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, st7703_of_match);
> +
> +static struct mipi_dsi_driver st7703_driver = {
> + .probe = st7703_probe,
> + .remove = st7703_remove,
> + .shutdown = st7703_shutdown,
> + .driver = {
> + .name = "st7703",
> + .of_match_table = st7703_of_match,
> + },
> +};
> +module_mipi_dsi_driver(st7703_driver);
> +
> +MODULE_AUTHOR("Icenowy Zheng <icenowy@xxxxxxx>");
> +MODULE_DESCRIPTION("DRM driver for Sitronix ST7703 MIPI DSI panel");
> +MODULE_LICENSE("GPL v2");
>