Lontium LT8912B is a DSI to HDMI bridge.
Signed-off-by: Adrien Grassein adrien.grassein@gmail.com --- MAINTAINERS | 1 + drivers/gpu/drm/bridge/Kconfig | 14 + drivers/gpu/drm/bridge/Makefile | 1 + drivers/gpu/drm/bridge/lontium-lt8912b.c | 817 +++++++++++++++++++++++ 4 files changed, 833 insertions(+) create mode 100644 drivers/gpu/drm/bridge/lontium-lt8912b.c
diff --git a/MAINTAINERS b/MAINTAINERS index 6366b8eac3f6..e075a74f57dd 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -10464,6 +10464,7 @@ LONTIUM LT8912B MIPI TO HDMI BRIDGE M: Adrien Grassein adrien.grassein@gmail.com S: Maintained F: Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml +F: drivers/gpu/drm/bridge/lontium-lt8912b.c
LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI) M: Sathya Prakash sathya.prakash@broadcom.com diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig index e4110d6ca7b3..f2c5ec75d2f5 100644 --- a/drivers/gpu/drm/bridge/Kconfig +++ b/drivers/gpu/drm/bridge/Kconfig @@ -48,6 +48,20 @@ config DRM_DISPLAY_CONNECTOR on ARM-based platforms. Saying Y here when this driver is not needed will not cause any issue.
+config DRM_LONTIUM_LT8912B + tristate "Lontium LT8912B DSI/HDMI bridge" + depends on OF + select DRM_PANEL_BRIDGE + select DRM_KMS_HELPER + select REGMAP_I2C + help + Driver for Lontium LT8912B DSI to HDMI bridge + chip driver. + Please say Y if you have such hardware. + + Say M here if you want to support this hardware as a module. + The module will be named "lontium-lt8912b". + config DRM_LONTIUM_LT9611 tristate "Lontium LT9611 DSI/HDMI bridge" select SND_SOC_HDMI_CODEC if SND_SOC diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile index 86e7acc76f8d..756ce401aad3 100644 --- a/drivers/gpu/drm/bridge/Makefile +++ b/drivers/gpu/drm/bridge/Makefile @@ -2,6 +2,7 @@ obj-$(CONFIG_DRM_CDNS_DSI) += cdns-dsi.o obj-$(CONFIG_DRM_CHRONTEL_CH7033) += chrontel-ch7033.o obj-$(CONFIG_DRM_DISPLAY_CONNECTOR) += display-connector.o +obj-$(CONFIG_DRM_LONTIUM_LT8912B) += lontium-lt8912b.o obj-$(CONFIG_DRM_LONTIUM_LT9611) += lontium-lt9611.o obj-$(CONFIG_DRM_LONTIUM_LT9611UXC) += lontium-lt9611uxc.o obj-$(CONFIG_DRM_LVDS_CODEC) += lvds-codec.o diff --git a/drivers/gpu/drm/bridge/lontium-lt8912b.c b/drivers/gpu/drm/bridge/lontium-lt8912b.c new file mode 100644 index 000000000000..f3ed8d8b7a64 --- /dev/null +++ b/drivers/gpu/drm/bridge/lontium-lt8912b.c @@ -0,0 +1,817 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2018, The Linux Foundation. All rights reserved. + */ + +#include <linux/device.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/gpio.h> +#include <linux/of_gpio.h> +#include <linux/regmap.h> + +#include <drm/drm_probe_helper.h> +#include <drm/drm_atomic_helper.h> +#include <drm/drm_mipi_dsi.h> +#include <drm/drm_of.h> + +#include <video/videomode.h> + +#define I2C_MAIN 0 +#define I2C_ADDR_MAIN 0x48 + +#define I2C_CEC_DSI 1 +#define I2C_ADDR_CEC_DSI 0x49 + +#define I2C_MAX_IDX 2 + +#define HPD_WORK_DELAY_MS 1000 + +struct lt8912 { + struct device *dev; + struct drm_bridge bridge; + struct drm_connector connector; + + struct i2c_client *i2c_client[I2C_MAX_IDX]; + struct regmap *regmap[I2C_MAX_IDX]; + + struct device_node *host_node; + struct drm_bridge *hdmi_port; + + struct mipi_dsi_device *dsi; + + struct gpio_desc *gp_reset; + + struct videomode mode; + + u8 data_lanes; + bool is_power_on; + bool is_attached; + + enum drm_connector_status cable_status; + struct workqueue_struct *workq; + struct delayed_work lt8912_check_hpd_work_id; +}; + +static int lt8912_write_init_config(struct lt8912 *lt) +{ + const struct reg_sequence seq[] = { + /* Digital clock en*/ + {0x08, 0xff}, + {0x09, 0xff}, + {0x0a, 0xff}, + {0x0b, 0x7c}, + {0x0c, 0xff}, + {0x42, 0x04}, + + /*Tx Analog*/ + {0x31, 0xb1}, + {0x32, 0xb1}, + {0x33, 0x0e}, + {0x37, 0x00}, + {0x38, 0x22}, + {0x60, 0x82}, + + /*Cbus Analog*/ + {0x39, 0x45}, + {0x3a, 0x00}, + {0x3b, 0x00}, + + /*HDMI Pll Analog*/ + {0x44, 0x31}, + {0x55, 0x44}, + {0x57, 0x01}, + {0x5a, 0x02}, + + /*MIPI Analog*/ + {0x3e, 0xd6}, + {0x3f, 0xd4}, + {0x41, 0x3c}, + {0xB2, 0x00}, + }; + + return regmap_multi_reg_write(lt->regmap[I2C_MAIN], seq, ARRAY_SIZE(seq)); +} + +static int lt8912_write_mipi_basic_config(struct lt8912 *lt) +{ + const struct reg_sequence seq[] = { + {0x12, 0x04}, + {0x14, 0x00}, + {0x15, 0x00}, + {0x1a, 0x03}, + {0x1b, 0x03}, + }; + + return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq)); +}; + +static int lt8912_write_dds_config(struct lt8912 *lt) +{ + const struct reg_sequence seq[] = { + {0x4e, 0xff}, + {0x4f, 0x56}, + {0x50, 0x69}, + {0x51, 0x80}, + {0x1f, 0x5e}, + {0x20, 0x01}, + {0x21, 0x2c}, + {0x22, 0x01}, + {0x23, 0xfa}, + {0x24, 0x00}, + {0x25, 0xc8}, + {0x26, 0x00}, + {0x27, 0x5e}, + {0x28, 0x01}, + {0x29, 0x2c}, + {0x2a, 0x01}, + {0x2b, 0xfa}, + {0x2c, 0x00}, + {0x2d, 0xc8}, + {0x2e, 0x00}, + {0x42, 0x64}, + {0x43, 0x00}, + {0x44, 0x04}, + {0x45, 0x00}, + {0x46, 0x59}, + {0x47, 0x00}, + {0x48, 0xf2}, + {0x49, 0x06}, + {0x4a, 0x00}, + {0x4b, 0x72}, + {0x4c, 0x45}, + {0x4d, 0x00}, + {0x52, 0x08}, + {0x53, 0x00}, + {0x54, 0xb2}, + {0x55, 0x00}, + {0x56, 0xe4}, + {0x57, 0x0d}, + {0x58, 0x00}, + {0x59, 0xe4}, + {0x5a, 0x8a}, + {0x5b, 0x00}, + {0x5c, 0x34}, + {0x1e, 0x4f}, + {0x51, 0x00}, + }; + + return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq)); +} + +static int lt8912_write_rxlogicres_config(struct lt8912 *lt) +{ + int ret; + + ret = regmap_write(lt->regmap[I2C_MAIN], 0x03, 0x7f); + usleep_range(10000, 20000); + ret |= regmap_write(lt->regmap[I2C_MAIN], 0x03, 0xff); + + return ret; +}; + +static int lt8912_write_lvds_config(struct lt8912 *lt) +{ + const struct reg_sequence seq[] = { + {0x44, 0x30}, + {0x51, 0x05}, + {0x50, 0x24}, + {0x51, 0x2d}, + {0x52, 0x04}, + {0x69, 0x0e}, + {0x69, 0x8e}, + {0x6a, 0x00}, + {0x6c, 0xb8}, + {0x6b, 0x51}, + {0x04, 0xfb}, + {0x04, 0xff}, + {0x7f, 0x00}, + {0xa8, 0x13}, + {0x02, 0xf7}, + {0x02, 0xff}, + {0x03, 0xcf}, + {0x03, 0xff}, + }; + + return regmap_multi_reg_write(lt->regmap[I2C_CEC_DSI], seq, ARRAY_SIZE(seq)); +}; + +static inline struct lt8912 *bridge_to_lt8912(struct drm_bridge *b) +{ + return container_of(b, struct lt8912, bridge); +} + +static inline struct lt8912 *connector_to_lt8912(struct drm_connector *c) +{ + return container_of(c, struct lt8912, connector); +} + +static const struct regmap_config lt8912_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = 0xff, +}; + +static int lt8912_init_i2c(struct lt8912 *lt, struct i2c_client *client) +{ + unsigned int i; + /* + * At this time we only initialize 2 chips, but the lt8912 provides + * a third interface for the audio over HDMI configuration. + */ + struct i2c_board_info info[] = { + { I2C_BOARD_INFO("lt8912p0", I2C_ADDR_MAIN), }, + { I2C_BOARD_INFO("lt8912p1", I2C_ADDR_CEC_DSI), }, + }; + + if (!lt) + return -ENODEV; + + for (i = 0; i < ARRAY_SIZE(info); i++) { + if (i > 0) { + lt->i2c_client[i] = i2c_new_dummy_device(client->adapter, + info[i].addr); + if (IS_ERR(lt->i2c_client[i])) + return PTR_ERR(lt->i2c_client[i]); + } + + lt->regmap[i] = devm_regmap_init_i2c(lt->i2c_client[i], + <8912_regmap_config); + if (IS_ERR(lt->regmap[i])) + return PTR_ERR(lt->regmap[i]); + } + return 0; +} + +static int lt8912_free_i2c(struct lt8912 *lt) +{ + unsigned int i; + + for (i = 1; i < I2C_MAX_IDX; i++) + i2c_unregister_device(lt->i2c_client[i]); + + return 0; +} + +static int lt8912_hard_power_on(struct lt8912 *lt) +{ + gpiod_set_value_cansleep(lt->gp_reset, 0); + msleep(20); + + return 0; +} + +static void lt8912_hard_power_off(struct lt8912 *lt) +{ + gpiod_set_value_cansleep(lt->gp_reset, 1); + msleep(20); + lt->is_power_on = false; +} + +static int lt8912_video_setup(struct lt8912 *lt) +{ + u32 hactive, h_total, hpw, hfp, hbp; + u32 vactive, v_total, vpw, vfp, vbp; + u8 settle = 0x08; + int ret; + + if (!lt) + return -EINVAL; + + hactive = lt->mode.hactive; + hfp = lt->mode.hfront_porch; + hpw = lt->mode.hsync_len; + hbp = lt->mode.hback_porch; + h_total = hactive + hfp + hpw + hbp; + + vactive = lt->mode.vactive; + vfp = lt->mode.vfront_porch; + vpw = lt->mode.vsync_len; + vbp = lt->mode.vback_porch; + v_total = vactive + vfp + vpw + vbp; + + if (vactive <= 600) + settle = 0x04; + else if (vactive == 1080) + settle = 0x0a; + + ret = regmap_write(lt->regmap[I2C_CEC_DSI], 0x10, 0x01); + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x11, settle); + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x18, hpw); + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x19, vpw); + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x1c, hactive & 0xff); + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x1d, hactive >> 8); + + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x2f, 0x0c); + + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x34, h_total & 0xff); + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x35, h_total >> 8); + + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x36, v_total & 0xff); + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x37, v_total >> 8); + + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x38, vbp & 0xff); + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x39, vbp >> 8); + + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3a, vfp & 0xff); + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3b, vfp >> 8); + + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3c, hbp & 0xff); + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3d, hbp >> 8); + + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3e, hfp & 0xff); + ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3f, hfp >> 8); + + return ret; +} + +static int lt8912_soft_power_on(struct lt8912 *lt) +{ + if (!lt->is_power_on) { + u32 lanes = lt->data_lanes; + + lt8912_write_init_config(lt); + regmap_write(lt->regmap[I2C_CEC_DSI], 0x13, lanes & 3); + + lt8912_write_mipi_basic_config(lt); + + lt->is_power_on = true; + } + + return 0; +} + +static int lt8912_video_on(struct lt8912 *lt) +{ + int ret; + + ret = lt8912_video_setup(lt); + if (ret < 0) + goto end; + + ret = lt8912_write_dds_config(lt); + if (ret < 0) + goto end; + + ret = lt8912_write_rxlogicres_config(lt); + if (ret < 0) + goto end; + + ret = lt8912_write_lvds_config(lt); + if (ret < 0) + goto end; + +end: + return ret; +} + + +static enum drm_connector_status lt8912_check_cable_status(struct lt8912 *lt) +{ + int ret; + unsigned int reg_val; + + ret = regmap_read(lt->regmap[I2C_MAIN], 0xC1, ®_val); + if (ret) + return connector_status_unknown; + + if (reg_val & BIT(7)) + return connector_status_connected; + + return connector_status_disconnected; +} + +static void lt8912_check_hpd_work(struct work_struct *work) +{ + struct delayed_work *dw = to_delayed_work(work); + struct lt8912 *lt = container_of(dw, struct lt8912, + lt8912_check_hpd_work_id); + struct drm_connector *connector = <->connector; + + enum drm_connector_status current_state = lt8912_check_cable_status(lt); + + if (current_state != lt->cable_status) { + drm_kms_helper_hotplug_event(connector->dev); + lt->cable_status = current_state; + } + + queue_delayed_work(lt->workq, + <->lt8912_check_hpd_work_id, + msecs_to_jiffies(HPD_WORK_DELAY_MS)); +} + +static void lt8912_setup_hpd(struct lt8912 *lt) +{ + INIT_DELAYED_WORK(<->lt8912_check_hpd_work_id, + lt8912_check_hpd_work); + queue_delayed_work(lt->workq, + <->lt8912_check_hpd_work_id, + msecs_to_jiffies(HPD_WORK_DELAY_MS)); +} + + +static enum drm_connector_status +lt8912_connector_detect(struct drm_connector *connector, bool force) +{ + struct lt8912 *lt = connector_to_lt8912(connector); + + if (lt->hdmi_port->ops & DRM_BRIDGE_OP_DETECT) + return drm_bridge_detect(lt->hdmi_port); + + return lt8912_check_cable_status(lt); +} + +static const struct drm_connector_funcs lt8912_connector_funcs = { + .detect = lt8912_connector_detect, + .fill_modes = drm_helper_probe_single_connector_modes, + .destroy = drm_connector_cleanup, + .reset = drm_atomic_helper_connector_reset, + .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, +}; + +static enum drm_mode_status +lt8912_connector_mode_valid(struct drm_connector *connector, + struct drm_display_mode *mode) +{ + if (mode->clock > 150000) + return MODE_CLOCK_HIGH; + + if (mode->hdisplay > 1920) + return MODE_BAD_HVALUE; + + if (mode->vdisplay > 1080) + return MODE_BAD_VVALUE; + + return MODE_OK; +} + +static int lt8912_connector_get_modes(struct drm_connector *connector) +{ + struct edid *edid; + int ret, num = 0; + struct lt8912 *lt = connector_to_lt8912(connector); + u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24; + + edid = drm_bridge_get_edid(lt->hdmi_port, connector); + if (edid) { + drm_connector_update_edid_property(connector, edid); + num = drm_add_edid_modes(connector, edid); + } else + return ret; + + ret = drm_display_info_set_bus_formats(&connector->display_info, + &bus_format, 1); + if (ret) + num = ret; + + kfree(edid); + return num; +} + +static const struct drm_connector_helper_funcs lt8912_connector_helper_funcs = { + .get_modes = lt8912_connector_get_modes, + .mode_valid = lt8912_connector_mode_valid, +}; + +static void lt8912_bridge_mode_set(struct drm_bridge *bridge, + const struct drm_display_mode *mode, + const struct drm_display_mode *adj) +{ + struct lt8912 *lt = bridge_to_lt8912(bridge); + + drm_display_mode_to_videomode(adj, <->mode); +} + +static void lt8912_bridge_enable(struct drm_bridge *bridge) +{ + struct lt8912 *lt = bridge_to_lt8912(bridge); + + lt8912_video_on(lt); +} + +static int lt8912_attach_dsi(struct lt8912 *lt) +{ + struct device *dev = lt->dev; + struct mipi_dsi_host *host; + struct mipi_dsi_device *dsi; + int ret = -1; + const struct mipi_dsi_device_info info = { .type = "lt8912", + .channel = 0, + .node = NULL, + }; + + host = of_find_mipi_dsi_host_by_node(lt->host_node); + if (!host) { + dev_err(dev, "failed to find dsi host\n"); + return -EPROBE_DEFER; + } + + dsi = mipi_dsi_device_register_full(host, &info); + if (IS_ERR(dsi)) { + ret = PTR_ERR(dsi); + dev_err(dev, "failed to create dsi device (%d)\n", ret); + goto err_dsi_device; + } + + lt->dsi = dsi; + + dsi->lanes = lt->data_lanes; + dsi->format = MIPI_DSI_FMT_RGB888; + + dsi->mode_flags = MIPI_DSI_MODE_VIDEO | + MIPI_DSI_MODE_VIDEO_BURST | + MIPI_DSI_MODE_LPM | + MIPI_DSI_MODE_EOT_PACKET; + + ret = mipi_dsi_attach(dsi); + if (ret < 0) { + dev_err(dev, "failed to attach dsi to host\n"); + goto err_dsi_attach; + } + + return 0; + +err_dsi_attach: + mipi_dsi_device_unregister(dsi); +err_dsi_device: + return ret; +} + +static void lt8912_detach_dsi(struct lt8912 *lt) +{ + mipi_dsi_detach(lt->dsi); + mipi_dsi_device_unregister(lt->dsi); +} + +static int lt8912_bridge_connector_init(struct drm_bridge *bridge) +{ + int ret; + struct lt8912 *lt = bridge_to_lt8912(bridge); + struct drm_connector *connector = <->connector; + + connector->polled = DRM_CONNECTOR_POLL_HPD; + + ret = drm_connector_init(bridge->dev, connector, + <8912_connector_funcs, + lt->hdmi_port->type); + if (ret) + goto exit; + + drm_connector_helper_add(connector, <8912_connector_helper_funcs); + + connector->dpms = DRM_MODE_DPMS_OFF; + drm_connector_attach_encoder(connector, bridge->encoder); + + lt8912_setup_hpd(lt); + +exit: + return ret; +} + +static int lt8912_bridge_attach(struct drm_bridge *bridge, + enum drm_bridge_attach_flags flags) +{ + struct lt8912 *lt = bridge_to_lt8912(bridge); + int ret; + + if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)) { + ret = lt8912_bridge_connector_init(bridge); + if (ret) { + dev_err(lt->dev, "Failed to init bridge ! (%d)\n", ret); + return ret; + } + } + + + ret = lt8912_hard_power_on(lt); + if (ret) + return ret; + + ret = lt8912_soft_power_on(lt); + if (ret) + goto error; + + ret = lt8912_attach_dsi(lt); + if (ret) + goto error; + + lt->is_attached = true; + + return 0; + +error: + lt8912_hard_power_off(lt); + return ret; +} + +static void lt8912_bridge_detach(struct drm_bridge *bridge) +{ + struct lt8912 *lt = bridge_to_lt8912(bridge); + + if (lt->is_attached) { + if (lt->hdmi_port->ops & DRM_BRIDGE_OP_HPD) + drm_bridge_hpd_disable(lt->hdmi_port); + lt8912_detach_dsi(lt); + lt8912_hard_power_off(lt); + } + + cancel_delayed_work_sync(<->lt8912_check_hpd_work_id); +} + +static enum drm_connector_status +lt8912_bridge_detect(struct drm_bridge *bridge) +{ + struct lt8912 *lt = bridge_to_lt8912(bridge); + + if (lt->hdmi_port->ops & DRM_BRIDGE_OP_DETECT) + return drm_bridge_detect(lt->hdmi_port); + + return lt8912_check_cable_status(lt); +} + +static struct edid *lt8912_bridge_get_edid(struct drm_bridge *bridge, + struct drm_connector *connector) +{ + struct lt8912 *lt = bridge_to_lt8912(bridge); + + /* + * edid must be read through the ddc bus but it must be + * given to the hdmi connector node. + */ + if (lt->hdmi_port->ops & DRM_BRIDGE_OP_EDID) + return drm_bridge_get_edid(lt->hdmi_port, connector); + + dev_warn(lt->dev, "The connected bridge does not supports DRM_BRIDGE_OP_EDID\n"); + return NULL; +} + +static void lt8912_bridge_hpd_enable(struct drm_bridge *bridge) +{ + struct lt8912 *lt = bridge_to_lt8912(bridge); + + if (!(lt->hdmi_port->ops & DRM_BRIDGE_OP_EDID)) + lt8912_setup_hpd(lt); +} + +static const struct drm_bridge_funcs lt8912_bridge_funcs = { + .attach = lt8912_bridge_attach, + .detach = lt8912_bridge_detach, + .mode_set = lt8912_bridge_mode_set, + .enable = lt8912_bridge_enable, + .detect = lt8912_bridge_detect, + .get_edid = lt8912_bridge_get_edid, + .hpd_enable = lt8912_bridge_hpd_enable +}; + +static int lt8912_parse_dt(struct lt8912 *lt) +{ + struct gpio_desc *gp_reset; + struct device *dev = lt->dev; + int ret = 0; + struct device_node *port_node; + struct device_node *endpoint; + + gp_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(gp_reset)) { + ret = PTR_ERR(gp_reset); + if (ret != -EPROBE_DEFER) + dev_err(dev, "Failed to get reset gpio: %d\n", ret); + return ret; + } + lt->gp_reset = gp_reset; + + + endpoint = of_graph_get_endpoint_by_regs(dev->of_node, 0, -1); + if (IS_ERR(endpoint)) { + ret = PTR_ERR(endpoint); + goto end; + } + + lt->data_lanes = of_property_count_u32_elems(endpoint, "data-lanes"); + of_node_put(endpoint); + + lt->host_node = of_graph_get_remote_node(dev->of_node, 0, -1); + if (!lt->host_node) { + dev_err(lt->dev, "%s: Failed to get remote port\n", __func__); + ret = -ENODEV; + goto end; + } + + port_node = of_graph_get_remote_node(dev->of_node, 1, -1); + if (!port_node) { + dev_err(lt->dev, "%s: Failed to get connector port\n", __func__); + ret = -ENODEV; + goto err_free_host_node; + } + + lt->hdmi_port = of_drm_find_bridge(port_node); + if (IS_ERR(lt->hdmi_port)) { + dev_err(lt->dev, "%s: Failed to get hdmi port\n", __func__); + ret = PTR_ERR(lt->hdmi_port); + of_node_put(lt->host_node); + goto end; + } + + if (!of_device_is_compatible(port_node, "hdmi-connector")) { + dev_err(lt->dev, "%s: Failed to get hdmi port\n", __func__); + ret = -EINVAL; + } + + of_node_put(port_node); + +end: + return ret; + +err_free_host_node: + of_node_put(lt->host_node); + return ret; +} + +static int lt8912_put_dt(struct lt8912 *lt) +{ + of_node_put(lt->host_node); + return 0; +} + +static int lt8912_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + static struct lt8912 *lt; + int ret = 0; + struct device *dev = &client->dev; + + lt = devm_kzalloc(dev, sizeof(struct lt8912), GFP_KERNEL); + if (!lt) + return -ENOMEM; + + lt->dev = dev; + lt->i2c_client[0] = client; + lt->cable_status = connector_status_unknown; + lt->workq = create_workqueue("lt8912_workq"); + + ret = lt8912_parse_dt(lt); + if (ret) + goto err_dt_parse; + + ret = lt8912_init_i2c(lt, client); + if (ret) + goto err_i2c; + + i2c_set_clientdata(client, lt); + + lt->bridge.funcs = <8912_bridge_funcs; + lt->bridge.of_node = dev->of_node; + lt->bridge.ops = (DRM_BRIDGE_OP_EDID | + DRM_BRIDGE_OP_DETECT | + DRM_BRIDGE_OP_HPD); + + drm_bridge_add(<->bridge); + + return 0; + +err_i2c: + lt8912_put_dt(lt); +err_dt_parse: + return ret; +} + +static int lt8912_remove(struct i2c_client *client) +{ + struct lt8912 *lt = i2c_get_clientdata(client); + + lt8912_bridge_detach(<->bridge); + drm_bridge_remove(<->bridge); + lt8912_free_i2c(lt); + lt8912_put_dt(lt); + destroy_workqueue(lt->workq); + return 0; +} + +static const struct of_device_id lt8912_dt_match[] = { + {.compatible = "lontium,lt8912b"}, + {} +}; +MODULE_DEVICE_TABLE(of, lt8912_dt_match); + +static const struct i2c_device_id lt8912_id[] = { + {"lt8912", 0}, + {}, +}; +MODULE_DEVICE_TABLE(i2c, lt8912_id); + +static struct i2c_driver lt8912_i2c_driver = { + .driver = { + .name = "lt8912", + .of_match_table = lt8912_dt_match, + .owner = THIS_MODULE, + }, + .probe = lt8912_probe, + .remove = lt8912_remove, + .id_table = lt8912_id, +}; +module_i2c_driver(lt8912_i2c_driver); + +MODULE_AUTHOR("Adrien Grassein adrien.grassein@gmail.com"); +MODULE_DESCRIPTION("lt8912 drm driver"); +MODULE_LICENSE("GPL v2");