Synaptics TDDI (Touch/Display Integration) panels utilize a single chip
for display and touch controllers. Implement a simple device driver for
such panels, along with its built-in LED backlight controller, and add
support for TD4101 and TD4300 panels in the driver.
Signed-off-by: Kaustabh Chakraborty <kauschl...@disroot.org>
---
drivers/gpu/drm/panel/Kconfig | 11 ++
drivers/gpu/drm/panel/Makefile | 1 +
drivers/gpu/drm/panel/panel-synaptics-tddi.c | 276 +++++++++++++++++++++++++++
3 files changed, 288 insertions(+)
diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index
407c5f6a268b2ec66e5d0eddae26b3368e4cb2cb..98708979ab45281628620bbe803fe8b597eb812d
100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -1045,6 +1045,17 @@ config DRM_PANEL_SYNAPTICS_R63353
Say Y if you want to enable support for panels based on the
Synaptics R63353 controller.
+config DRM_PANEL_SYNAPTICS_TDDI
+ tristate "Synaptics TDDI display panels"
+ depends on OF
+ depends on DRM_MIPI_DSI
+ depends on BACKLIGHT_CLASS_DEVICE
+ help
+ Say Y if you want to enable support for the Synaptics TDDI display
+ panels. There are multiple MIPI DSI panels manufactured under the TDDI
+ namesake, with varying resolutions and data lanes. They also have a
+ built-in LED backlight and a touch controller.
+
config DRM_PANEL_TDO_TL070WSH30
tristate "TDO TL070WSH30 DSI panel"
depends on OF
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index
3615a761b44f9de0b4a653be157d8e0bcbc8f6b7..2535e1c9df76451d1c66d7d211ac9bfbf18dc80e
100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -100,6 +100,7 @@ obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7703) +=
panel-sitronix-st7703.o
obj-$(CONFIG_DRM_PANEL_SITRONIX_ST7789V) += panel-sitronix-st7789v.o
obj-$(CONFIG_DRM_PANEL_SUMMIT) += panel-summit.o
obj-$(CONFIG_DRM_PANEL_SYNAPTICS_R63353) += panel-synaptics-r63353.o
+obj-$(CONFIG_DRM_PANEL_SYNAPTICS_TDDI) += panel-synaptics-tddi.o
obj-$(CONFIG_DRM_PANEL_SONY_ACX565AKM) += panel-sony-acx565akm.o
obj-$(CONFIG_DRM_PANEL_SONY_TD4353_JDI) += panel-sony-td4353-jdi.o
obj-$(CONFIG_DRM_PANEL_SONY_TULIP_TRULY_NT35521) +=
panel-sony-tulip-truly-nt35521.o
diff --git a/drivers/gpu/drm/panel/panel-synaptics-tddi.c
b/drivers/gpu/drm/panel/panel-synaptics-tddi.c
new file mode 100644
index
0000000000000000000000000000000000000000..a4b3cbdebb6ca4062c02c6e7ac184f3ec245926a
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-synaptics-tddi.c
@@ -0,0 +1,276 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Synaptics TDDI display panel driver.
+ *
+ * Copyright (C) 2025 Kaustabh Chakraborty <kauschl...@disroot.org>
+ */
+
+#include <linux/backlight.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/of.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_probe_helper.h>
+
+struct tddi_panel_data {
+ u8 lanes;
+ /* wait timings for panel enable */
+ u8 delay_ms_sleep_exit;
+ u8 delay_ms_display_on;
+ /* wait timings for panel disable */
+ u8 delay_ms_display_off;
+ u8 delay_ms_sleep_enter;
+};
+
+struct tddi_ctx {
+ struct drm_panel panel;
+ struct mipi_dsi_device *dsi;
+ struct drm_display_mode mode;
+ struct backlight_device *backlight;
+ const struct tddi_panel_data *data;
+ struct regulator_bulk_data *supplies;
+ struct gpio_desc *reset_gpio;
+ struct gpio_desc *backlight_gpio;
+};
+
+static const struct regulator_bulk_data tddi_supplies[] = {
+ { .supply = "vio" },
+ { .supply = "vsn" },
+ { .supply = "vsp" },
+};
+
+static inline struct tddi_ctx *to_tddi_ctx(struct drm_panel *panel)
+{
+ return container_of(panel, struct tddi_ctx, panel);
+}
+
+static int tddi_update_status(struct backlight_device *backlight)
+{
+ struct tddi_ctx *ctx = bl_get_data(backlight);
+ struct mipi_dsi_multi_context dsi = { .dsi = ctx->dsi };
+ u8 brightness = backlight_get_brightness(backlight);
+
+ if (!ctx->panel.enabled)
+ return 0;
+
+ mipi_dsi_dcs_set_display_brightness_multi(&dsi, brightness);
+
+ return dsi.accum_err;
+}
+
+static int tddi_prepare(struct drm_panel *panel)
+{
+ struct tddi_ctx *ctx = to_tddi_ctx(panel);
+ struct device *dev = &ctx->dsi->dev;
+ int ret;
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(tddi_supplies), ctx->supplies);
+ if (ret < 0) {
+ dev_err(dev, "failed to enable regulators: %d\n", ret);
+ return ret;
+ }
+
+ gpiod_set_value_cansleep(ctx->reset_gpio, 0);
+ usleep_range(5000, 6000);
+ gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+ usleep_range(5000, 6000);
+ gpiod_set_value_cansleep(ctx->reset_gpio, 0);
+ usleep_range(10000, 11000);
+
+ gpiod_set_value_cansleep(ctx->backlight_gpio, 0);
+ usleep_range(5000, 6000);
+
+ return 0;
+}
+
+static int tddi_unprepare(struct drm_panel *panel)
+{
+ struct tddi_ctx *ctx = to_tddi_ctx(panel);
+
+ gpiod_set_value_cansleep(ctx->backlight_gpio, 1);
+ usleep_range(5000, 6000);
+
+ gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+ usleep_range(5000, 6000);
+
+ regulator_bulk_disable(ARRAY_SIZE(tddi_supplies), ctx->supplies);
+
+ return 0;
+}
+
+static int tddi_enable(struct drm_panel *panel)
+{
+ struct tddi_ctx *ctx = to_tddi_ctx(panel);
+ struct mipi_dsi_multi_context dsi = { .dsi = ctx->dsi };
+ u8 brightness = ctx->backlight->props.brightness;
+
+ mipi_dsi_dcs_write_seq_multi(&dsi, MIPI_DCS_WRITE_POWER_SAVE, 0x00);
+ mipi_dsi_dcs_write_seq_multi(&dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
0x0c);
+
+ mipi_dsi_dcs_exit_sleep_mode_multi(&dsi);
+ mipi_dsi_msleep(&dsi, ctx->data->delay_ms_sleep_exit);
+
+ /* sync the panel with the backlight's brightness level */
+ mipi_dsi_dcs_set_display_brightness_multi(&dsi, brightness);
+
+ mipi_dsi_dcs_set_display_on_multi(&dsi);
+ mipi_dsi_msleep(&dsi, ctx->data->delay_ms_display_on);
+
+ return dsi.accum_err;
+};
+
+static int tddi_disable(struct drm_panel *panel)
+{
+ struct tddi_ctx *ctx = to_tddi_ctx(panel);
+ struct mipi_dsi_multi_context dsi = { .dsi = ctx->dsi };
+
+ mipi_dsi_dcs_set_display_off_multi(&dsi);
+ mipi_dsi_msleep(&dsi, ctx->data->delay_ms_display_off);
+
+ mipi_dsi_dcs_enter_sleep_mode_multi(&dsi);
+ mipi_dsi_msleep(&dsi, ctx->data->delay_ms_sleep_enter);
+
+ return dsi.accum_err;
+}
+
+static int tddi_get_modes(struct drm_panel *panel,
+ struct drm_connector *connector)
+{
+ struct tddi_ctx *ctx = to_tddi_ctx(panel);
+
+ return drm_connector_helper_get_modes_fixed(connector, &ctx->mode);
+}
+
+static const struct backlight_ops tddi_bl_ops = {
+ .update_status = tddi_update_status,
+};
+
+static const struct backlight_properties tddi_bl_props = {
+ .type = BACKLIGHT_PLATFORM,
+ .brightness = 255,
+ .max_brightness = 255,
+};
+
+static const struct drm_panel_funcs tddi_drm_panel_funcs = {
+ .prepare = tddi_prepare,
+ .unprepare = tddi_unprepare,
+ .enable = tddi_enable,
+ .disable = tddi_disable,
+ .get_modes = tddi_get_modes,
+};
+
+static int tddi_probe(struct mipi_dsi_device *dsi)
+{
+ struct device *dev = &dsi->dev;
+ struct tddi_ctx *ctx;
+ int ret;
+
+ ctx = devm_drm_panel_alloc(dev, struct tddi_ctx, panel,
+ &tddi_drm_panel_funcs,
DRM_MODE_CONNECTOR_DSI);
+ if (IS_ERR(ctx))
+ return PTR_ERR(ctx);
+
+ ctx->data = of_device_get_match_data(dev);
+
+ ctx->dsi = dsi;
+ mipi_dsi_set_drvdata(dsi, ctx);
+
+ ret = devm_regulator_bulk_get_const(dev, ARRAY_SIZE(tddi_supplies),
+ tddi_supplies, &ctx->supplies);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "failed to get regulators\n");
+
+ ctx->backlight_gpio = devm_gpiod_get_optional(dev, "backlight",
GPIOD_ASIS);
+ if (IS_ERR(ctx->backlight_gpio))
+ return dev_err_probe(dev, PTR_ERR(ctx->backlight_gpio),
+ "failed to get backlight-gpios\n");
+
+ ctx->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_ASIS);
+ if (IS_ERR(ctx->reset_gpio))
+ return dev_err_probe(dev, PTR_ERR(ctx->reset_gpio),
+ "failed to get reset-gpios\n");
+
+ ret = of_get_drm_panel_display_mode(dev->of_node, &ctx->mode, NULL);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "failed to get panel timings\n");
+
+ ctx->backlight = devm_backlight_device_register(dev, dev_name(dev), dev,
+ ctx, &tddi_bl_ops,
+ &tddi_bl_props);
+ if (IS_ERR(ctx->backlight))
+ return dev_err_probe(dev, PTR_ERR(ctx->backlight),
+ "failed to register backlight device");
+
+ dsi->lanes = ctx->data->lanes;
+ dsi->format = MIPI_DSI_FMT_RGB888;
+ dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
+ MIPI_DSI_MODE_VIDEO_NO_HFP;
+
+ ctx->panel.prepare_prev_first = true;
+ drm_panel_add(&ctx->panel);
+
+ ret = devm_mipi_dsi_attach(dev, dsi);
+ if (ret < 0) {
+ drm_panel_remove(&ctx->panel);
+ return dev_err_probe(dev, ret, "failed to attach to DSI
host\n");
+ }
+
+ return 0;
+}
+
+static void tddi_remove(struct mipi_dsi_device *dsi)
+{
+ struct tddi_ctx *ctx = mipi_dsi_get_drvdata(dsi);
+
+ drm_panel_remove(&ctx->panel);
+}
+
+static const struct tddi_panel_data td4101_panel_data = {
+ .lanes = 2,
+ /* wait timings for panel enable */
+ .delay_ms_sleep_exit = 100,
+ .delay_ms_display_on = 0,
+ /* wait timings for panel disable */
+ .delay_ms_display_off = 20,
+ .delay_ms_sleep_enter = 90,
+};
+
+static const struct tddi_panel_data td4300_panel_data = {
+ .lanes = 4,
+ /* wait timings for panel enable */
+ .delay_ms_sleep_exit = 100,
+ .delay_ms_display_on = 0,
+ /* wait timings for panel disable */
+ .delay_ms_display_off = 0,
+ .delay_ms_sleep_enter = 0,
+};
+
+static const struct of_device_id tddi_of_device_id[] = {
+ {
+ .compatible = "syna,td4101-panel",
+ .data = &td4101_panel_data,
+ }, {
+ .compatible = "syna,td4300-panel",
+ .data = &td4300_panel_data,
+ }, { }
+};
+MODULE_DEVICE_TABLE(of, tddi_of_device_id);
+
+static struct mipi_dsi_driver tddi_dsi_driver = {
+ .probe = tddi_probe,
+ .remove = tddi_remove,
+ .driver = {
+ .name = "panel-synaptics-tddi",
+ .of_match_table = tddi_of_device_id,
+ },
+};
+module_mipi_dsi_driver(tddi_dsi_driver);
+
+MODULE_AUTHOR("Kaustabh Chakraborty <kauschl...@disroot.org>");
+MODULE_DESCRIPTION("Synaptics TDDI Display Panel Driver");
+MODULE_LICENSE("GPL");
--
2.50.0
