[PATCH v1 2/3] drm/bridge: Add THine THC63LVD827 LVDS encoder
Francesco Dolcini
francesco at dolcini.it
Tue Sep 8 03:02:26 PDT 2026
From: Francesco Dolcini <francesco.dolcini at toradex.com>
Add THC63LVD827 DPI to LVDS bridge driver. The driver supports
configuring the LVDS data mapping. As of now only single link LVDS is
supported, dual link support can be added if/when needed.
Signed-off-by: Francesco Dolcini <francesco.dolcini at toradex.com>
---
MAINTAINERS | 1 +
drivers/gpu/drm/bridge/Kconfig | 11 ++
drivers/gpu/drm/bridge/Makefile | 1 +
drivers/gpu/drm/bridge/thc63lvd827.c | 193 +++++++++++++++++++++++++++
4 files changed, 206 insertions(+)
create mode 100644 drivers/gpu/drm/bridge/thc63lvd827.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 0b5a25a35367..ee24b15b26d3 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8584,6 +8584,7 @@ DRM DRIVER FOR THINE THC63LVD827 DPI TO LVDS BRIDGE
M: Francesco Dolcini <francesco at dolcini.it>
S: Maintained
F: Documentation/devicetree/bindings/display/bridge/thine,thc63lvd827.yaml
+F: drivers/gpu/drm/bridge/thc63lvd827.c
DRM DRIVER FOR TI DLPC3433 MIPI DSI TO DMD BRIDGE
M: Jagan Teki <jagan at amarulasolutions.com>
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index 4a57d49b4c6d..70ebc6b50e59 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -365,6 +365,17 @@ config DRM_THINE_THC63LVD1024
help
Thine THC63LVD1024 LVDS/parallel converter driver.
+config DRM_THINE_THC63LVD827
+ tristate "THine THC63LVD827 DPI/LVDS bridge"
+ depends on OF
+ select DRM_KMS_HELPER
+ help
+ Enable support for the THine THC63LVD827 DPI to LVDS bridge.
+
+ The device converts a parallel RGB display interface to an LVDS
+ output for connection to LVDS display panels.
+ The bridge supports configurable JEIDA and VESA LVDS data mapping.
+
config DRM_THEAD_TH1520_DW_HDMI
tristate "T-Head TH1520 DesignWare HDMI bridge"
depends on OF
diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
index 15cc821d85b7..5d578f7112c8 100644
--- a/drivers/gpu/drm/bridge/Makefile
+++ b/drivers/gpu/drm/bridge/Makefile
@@ -33,6 +33,7 @@ obj-$(CONFIG_DRM_SIMPLE_BRIDGE) += simple-bridge.o
obj-$(CONFIG_DRM_SOLOMON_SSD2825) += ssd2825.o
obj-$(CONFIG_DRM_THEAD_TH1520_DW_HDMI) += th1520-dw-hdmi.o
obj-$(CONFIG_DRM_THINE_THC63LVD1024) += thc63lvd1024.o
+obj-$(CONFIG_DRM_THINE_THC63LVD827) += thc63lvd827.o
obj-$(CONFIG_DRM_TOSHIBA_TC358762) += tc358762.o
obj-$(CONFIG_DRM_TOSHIBA_TC358764) += tc358764.o
obj-$(CONFIG_DRM_TOSHIBA_TC358767) += tc358767.o
diff --git a/drivers/gpu/drm/bridge/thc63lvd827.c b/drivers/gpu/drm/bridge/thc63lvd827.c
new file mode 100644
index 000000000000..d3c7e0fff126
--- /dev/null
+++ b/drivers/gpu/drm/bridge/thc63lvd827.c
@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) Toradex
+ * Author: Francesco Dolcini <francesco.dolcini at toradex.com>
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/media-bus-format.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_of.h>
+
+struct thc63lvd827 {
+ struct device *dev;
+ struct drm_bridge bridge;
+ struct drm_bridge *next_bridge;
+
+ struct gpio_desc *map_gpio;
+ struct gpio_desc *mode_gpio;
+ struct gpio_desc *b6b8_gpio;
+ struct gpio_desc *pd_gpio;
+
+ struct drm_bridge_timings timings;
+};
+
+static struct thc63lvd827 *bridge_to_thc63lvd827(struct drm_bridge *bridge)
+{
+ return container_of(bridge, struct thc63lvd827, bridge);
+}
+
+static int thc63lvd827_attach(struct drm_bridge *bridge,
+ struct drm_encoder *encoder,
+ enum drm_bridge_attach_flags flags)
+{
+ struct thc63lvd827 *thc63lvd827 = bridge_to_thc63lvd827(bridge);
+
+ return drm_bridge_attach(encoder, thc63lvd827->next_bridge, bridge, flags);
+}
+
+static u32 *
+thc63lvd827_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
+ struct drm_bridge_state *bridge_state,
+ struct drm_crtc_state *crtc_state,
+ struct drm_connector_state *conn_state,
+ u32 output_fmt,
+ unsigned int *num_input_fmts)
+{
+ u32 *input_fmts;
+
+ *num_input_fmts = 0;
+
+ input_fmts = kmalloc_obj(*input_fmts);
+ if (!input_fmts)
+ return NULL;
+
+ input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X24;
+ *num_input_fmts = 1;
+
+ return input_fmts;
+}
+
+static void thc63lvd827_atomic_pre_enable(struct drm_bridge *bridge,
+ struct drm_atomic_commit *state)
+{
+ struct thc63lvd827 *thc63lvd827 = bridge_to_thc63lvd827(bridge);
+ const struct drm_bridge_state *bridge_state;
+ int b6b8_val, map_val;
+
+ bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
+
+ /*
+ * 6B/8B: H = 6-bit (21-bit) mode, L = 8-bit (27-bit) mode.
+ * MAP: H = Mapping Mode 1, L = Mapping Mode 2.
+ */
+ switch (bridge_state->output_bus_cfg.format) {
+ case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
+ b6b8_val = 1;
+ map_val = 1;
+ break;
+ case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
+ b6b8_val = 0;
+ map_val = 1;
+ break;
+ default:
+ case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
+ b6b8_val = 0;
+ map_val = 0;
+ break;
+ }
+
+ gpiod_set_value_cansleep(thc63lvd827->b6b8_gpio, b6b8_val);
+ gpiod_set_value_cansleep(thc63lvd827->map_gpio, map_val);
+ gpiod_set_value_cansleep(thc63lvd827->pd_gpio, 0);
+}
+
+static void thc63lvd827_atomic_post_disable(struct drm_bridge *bridge,
+ struct drm_atomic_commit *state)
+{
+ struct thc63lvd827 *thc63lvd827 = bridge_to_thc63lvd827(bridge);
+
+ gpiod_set_value_cansleep(thc63lvd827->pd_gpio, 1);
+}
+
+static const struct drm_bridge_funcs thc63lvd827_bridge_funcs = {
+ .attach = thc63lvd827_attach,
+ .atomic_pre_enable = thc63lvd827_atomic_pre_enable,
+ .atomic_post_disable = thc63lvd827_atomic_post_disable,
+ .atomic_get_input_bus_fmts = thc63lvd827_atomic_get_input_bus_fmts,
+ .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
+ .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
+ .atomic_create_state = drm_atomic_helper_bridge_create_state,
+};
+
+static int thc63lvd827_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct thc63lvd827 *thc63lvd827;
+ struct device_node *ep;
+ u32 pclk_sample = 0;
+
+ thc63lvd827 = devm_drm_bridge_alloc(dev, struct thc63lvd827, bridge,
+ &thc63lvd827_bridge_funcs);
+ if (IS_ERR(thc63lvd827))
+ return PTR_ERR(thc63lvd827);
+
+ thc63lvd827->dev = dev;
+
+ thc63lvd827->map_gpio = devm_gpiod_get_optional(dev, "map", GPIOD_OUT_LOW);
+ if (IS_ERR(thc63lvd827->map_gpio))
+ return dev_err_probe(dev, PTR_ERR(thc63lvd827->map_gpio),
+ "failed to get MAP GPIO\n");
+
+ thc63lvd827->mode_gpio = devm_gpiod_get_optional(dev, "mode", GPIOD_OUT_HIGH);
+ if (IS_ERR(thc63lvd827->mode_gpio))
+ return dev_err_probe(dev, PTR_ERR(thc63lvd827->mode_gpio),
+ "failed to get MODE GPIO\n");
+
+ thc63lvd827->b6b8_gpio = devm_gpiod_get_optional(dev, "b6b8", GPIOD_OUT_LOW);
+ if (IS_ERR(thc63lvd827->b6b8_gpio))
+ return dev_err_probe(dev, PTR_ERR(thc63lvd827->b6b8_gpio),
+ "failed to get 6B/8B GPIO\n");
+
+ thc63lvd827->pd_gpio = devm_gpiod_get_optional(dev, "powerdown", GPIOD_OUT_HIGH);
+ if (IS_ERR(thc63lvd827->pd_gpio))
+ return dev_err_probe(dev, PTR_ERR(thc63lvd827->pd_gpio),
+ "failed to get /PDWN GPIO\n");
+
+ thc63lvd827->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0);
+ if (IS_ERR(thc63lvd827->next_bridge))
+ return dev_err_probe(dev, PTR_ERR(thc63lvd827->next_bridge),
+ "failed to get downstream bridge\n");
+
+ ep = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
+ of_property_read_u32(ep, "pclk-sample", &pclk_sample);
+ of_node_put(ep);
+
+ if (pclk_sample == 1)
+ thc63lvd827->timings.input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE;
+ else
+ thc63lvd827->timings.input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE;
+
+ thc63lvd827->bridge.of_node = dev->of_node;
+ thc63lvd827->bridge.timings = &thc63lvd827->timings;
+ thc63lvd827->bridge.type = DRM_MODE_CONNECTOR_LVDS;
+
+ platform_set_drvdata(pdev, thc63lvd827);
+
+ return devm_drm_bridge_add(dev, &thc63lvd827->bridge);
+}
+
+static const struct of_device_id thc63lvd827_of_match[] = {
+ { .compatible = "thine,thc63lvd827" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, thc63lvd827_of_match);
+
+static struct platform_driver thc63lvd827_driver = {
+ .probe = thc63lvd827_probe,
+ .driver = {
+ .name = "thc63lvd827",
+ .of_match_table = thc63lvd827_of_match,
+ },
+};
+module_platform_driver(thc63lvd827_driver);
+
+MODULE_DESCRIPTION("THine THC63LVD827 DPI to LVDS bridge driver");
+MODULE_LICENSE("GPL");
--
2.47.3
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