ti-fpdlink/ti-fpdlink.c:

  - A wrapper bridge driver for TI FPD LINK serializer and deserializer.

  - This driver takes care of initilizing FPD link connection between
  serializer and deserializer.

  - of_drm_find_bridge() looks up matching serializer/deserializer bridges
  from given serializer/deserializer device node.

ti-fpdlink/ti-ub927.c:

  - drm bridge driver for TI DS90UB927 FPD-Link III Serializer

ti-fpdlink/ti-ub949.c:

  - drm bridge driver for TI DS90UB949 FPD-Link III Serializer

ti-fpdlink/ti-ub948.c:

  - drm bridge driver for TI DS90UB948 FPD-Link III Deserializer

Signed-off-by: Vince Kim <vince.k....@gmail.com>
---
 drivers/gpu/drm/bridge/Kconfig                |   2 +
 drivers/gpu/drm/bridge/Makefile               |   1 +
 drivers/gpu/drm/bridge/ti-fpdlink/Kconfig     |  32 ++
 drivers/gpu/drm/bridge/ti-fpdlink/Makefile    |   5 +
 .../gpu/drm/bridge/ti-fpdlink/ti-ds90ub927.c  | 421 +++++++++++++++++
 .../gpu/drm/bridge/ti-fpdlink/ti-ds90ub948.c  | 333 ++++++++++++++
 .../gpu/drm/bridge/ti-fpdlink/ti-ds90ub949.c  | 435 ++++++++++++++++++
 .../gpu/drm/bridge/ti-fpdlink/ti-fpdlink.c    | 396 ++++++++++++++++
 .../gpu/drm/bridge/ti-fpdlink/ti-fpdlink.h    |  70 +++
 9 files changed, 1695 insertions(+)
 create mode 100644 drivers/gpu/drm/bridge/ti-fpdlink/Kconfig
 create mode 100644 drivers/gpu/drm/bridge/ti-fpdlink/Makefile
 create mode 100644 drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub927.c
 create mode 100644 drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub948.c
 create mode 100644 drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub949.c
 create mode 100644 drivers/gpu/drm/bridge/ti-fpdlink/ti-fpdlink.c
 create mode 100644 drivers/gpu/drm/bridge/ti-fpdlink/ti-fpdlink.h

diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index 8840f396a7b6..f37a3c50dc69 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -154,4 +154,6 @@ source "drivers/gpu/drm/bridge/adv7511/Kconfig"
 
 source "drivers/gpu/drm/bridge/synopsys/Kconfig"
 
+source "drivers/gpu/drm/bridge/ti-fpdlink/Kconfig"
+
 endmenu
diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
index 4934fcf5a6f8..6d251aba65d4 100644
--- a/drivers/gpu/drm/bridge/Makefile
+++ b/drivers/gpu/drm/bridge/Makefile
@@ -16,4 +16,5 @@ obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix/
 obj-$(CONFIG_DRM_I2C_ADV7511) += adv7511/
 obj-$(CONFIG_DRM_TI_SN65DSI86) += ti-sn65dsi86.o
 obj-$(CONFIG_DRM_TI_TFP410) += ti-tfp410.o
+obj-$(CONFIG_DRM_TI_FPDLINK) += ti-fpdlink/
 obj-y += synopsys/
diff --git a/drivers/gpu/drm/bridge/ti-fpdlink/Kconfig 
b/drivers/gpu/drm/bridge/ti-fpdlink/Kconfig
new file mode 100644
index 000000000000..4e81e6454cfe
--- /dev/null
+++ b/drivers/gpu/drm/bridge/ti-fpdlink/Kconfig
@@ -0,0 +1,32 @@
+
+config DRM_TI_FPDLINK
+       tristate "TI FPD-Link III bridge"
+       depends on OF
+       select DRM_KMS_HELPER
+       help
+          Support wrapper bridge driver for Texas Instruments FPD-Link
+          Serializer and Deserializer chip.
+
+config DRM_TI_UB949
+       tristate "TI FPD-Link III UB949 Serializer"
+       depends on DRM_TI_FPDLINK
+       select DRM_KMS_HELPER
+       help
+          Support Texas Instruments FPD-Link III DS90UB949
+          Serializer which converts HDMI input to FPD-link output.
+
+config DRM_TI_UB948
+       tristate "TI FPD-Link III UB948 Deserializer"
+       depends on DRM_TI_FPDLINK
+       select DRM_KMS_HELPER
+       help
+          Supports Texas Instruments FPD-Link III DS90UB948
+          Deserializer which converts FPD-link input to LVDS output.
+
+config DRM_TI_UB927
+       tristate "TI FPD-Link III UB927 Serializer"
+       depends on DRM_TI_FPDLINK
+       select DRM_KMS_HELPER
+       help
+          Support Texas Instruments FPD-Link III DS90UB927
+          Serializer which converts LVDS input to FPD-link output.
diff --git a/drivers/gpu/drm/bridge/ti-fpdlink/Makefile 
b/drivers/gpu/drm/bridge/ti-fpdlink/Makefile
new file mode 100644
index 000000000000..a176a388f872
--- /dev/null
+++ b/drivers/gpu/drm/bridge/ti-fpdlink/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_DRM_TI_FPDLINK) += ti-fpdlink.o
+obj-$(CONFIG_DRM_TI_UB949) += ti-ds90ub949.o
+obj-$(CONFIG_DRM_TI_UB948) += ti-ds90ub948.o
+obj-$(CONFIG_DRM_TI_UB927) += ti-ds90ub927.o
diff --git a/drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub927.c 
b/drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub927.c
new file mode 100644
index 000000000000..88173f8b18ae
--- /dev/null
+++ b/drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub927.c
@@ -0,0 +1,421 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TI FPD-LinkIII DS90UB927 driver
+ *
+ * Copyright (C) 2019 Lucid Motors Inc.
+ *
+ * Contact: Vince Kim <vince.k....@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/of_gpio.h>
+#include <drm/drmP.h>
+#include "ti-fpdlink.h"
+
+#define UB927_RESET_REG                                0x01
+#define UB927_RESET_DGTL_RST1                  (1<<1)
+
+#define UB927_GS_REG                           0x0c
+#define UB927_GS_BIST_CRC_ERROR                        (1<<3)
+#define UB927_GS_PCLK_DETECT                   (1<<2)
+#define UB927_GS_DES_CRC_ERROR                 (1<<1)
+#define UB927_GS_LINK_DETECT                   (1<<0)
+
+#define UB927_I2C_CTRL_REG                     0x17
+#define UB927_I2C_CTRL_PASS_ALL                        (1<<7)
+
+#define MAX_I2C_RETRY 10
+
+
+static inline struct fpdlink_dev *
+drm_bridge_to_ub927(struct drm_bridge *bridge)
+{
+       return container_of(bridge, struct fpdlink_dev, bridge);
+}
+
+static inline int
+regmap_write_fpdlink(struct regmap *map, unsigned int reg, unsigned int val)
+{
+       int count = MAX_I2C_RETRY;
+       int ret = -1;
+
+       while (count-- && (ret = regmap_write(map, reg, val)))
+               usleep_range(1000, 1100);
+
+       return ret;
+}
+
+static const struct regmap_config ub927_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 8,
+       .cache_type = REGCACHE_NONE,
+       .max_register = 0xff,
+};
+
+static int ub927_enable(struct fpdlink_dev *ub927)
+{
+       if (gpio_is_valid(ub927->gpio_power_en)) {
+               gpio_set_value(ub927->gpio_power_en, 1);
+       } else {
+               if (ub927->gpio_power_en > 0) {
+                       dev_err(ub927->dev, "invalid gpio for gpio_disp_en 
%s\n",
+                               ub927->gpio_name);
+                       return -ENXIO;
+               }
+       }
+       msleep(200);
+       return 0;
+}
+
+static void ub927_disable(struct fpdlink_dev *ub927)
+{
+       regmap_write_fpdlink(ub927->regmap, UB927_RESET_REG,
+                       UB927_RESET_DGTL_RST1);
+}
+
+static int ub927_reset(struct fpdlink_dev *ub927)
+{
+       int ret;
+
+       ret = regmap_write_fpdlink(ub927->regmap, UB927_RESET_REG,
+                                  UB927_RESET_DGTL_RST1);
+       usleep_range(1000, 1500);
+       return ret;
+}
+
+static int ub927_enable_i2c_passthrough(struct fpdlink_dev *ub927)
+{
+       int ret;
+       unsigned int val;
+
+       ret = regmap_read(ub927->regmap, UB927_I2C_CTRL_REG, &val);
+       if (ret < 0) {
+               dev_err(ub927->dev, "failed on regmap_read at %s()\n",
+                               __func__);
+               return ret;
+       }
+
+       ret = regmap_write_fpdlink(ub927->regmap, UB927_I2C_CTRL_REG,
+                                  (val | UB927_I2C_CTRL_PASS_ALL));
+       if (ret < 0) {
+               dev_err(ub927->dev, "failed onregmap_write_fpdlink at %s()\n",
+                       __func__);
+               return ret;
+       }
+
+       msleep(100);
+       return ret;
+}
+
+static int ub927_reg_write(struct fpdlink_dev *ub927, u8 reg, u8 val)
+{
+       return regmap_write_fpdlink(ub927->regmap, reg, val);
+}
+
+static int ub927_update_config(struct fpdlink_dev *ub927)
+{
+       int i = 0;
+       int size;
+       u8 *config_array;
+       int ret = 0;
+
+       size = ub927->config_array_size;
+       config_array = ub927->config_array;
+
+       if (!config_array)
+               return 0;
+
+       while (i < size) {
+               ret = regmap_write_fpdlink(ub927->regmap, config_array[i],
+                                          config_array[i+1]);
+               if (ret) {
+                       dev_err(ub927->dev,
+                               "%s: failed to update register\n", __func__);
+                       return -EINVAL;
+               }
+               i += 2;
+       }
+       return 0;
+}
+
+static bool ub927_link_detect(struct fpdlink_dev *ub927)
+{
+       unsigned int val;
+       int count, ret;
+
+       mutex_lock(&ub927->lock);
+       ub927->link_status = not_detected;
+
+       for (count = 0; count < MAX_I2C_RETRY; count++) {
+               usleep_range(10000, 15000);
+               ret = regmap_read(ub927->regmap, UB927_GS_REG, &val);
+               if (!ret && (val & UB927_GS_LINK_DETECT)) {
+                       dev_info(ub927->dev,
+                                "LVDS: %d Serializer FPD link ready!\n",
+                                ub927->index);
+                       ub927->link_status = detected;
+                       ret = true;
+                       goto done;
+               }
+       }
+
+       dev_info(ub927->dev, "LVDS: %d Serializer FPD link failed!!\n",
+                       ub927->index);
+
+done:
+       mutex_unlock(&ub927->lock);
+
+       if (ret < 0) {
+               dev_info(ub927->dev,
+                               "failed on regmap_read at %s()\n", __func__);
+       }
+       return (ub927->link_status ? true : false);
+}
+
+static bool ub927_pixel_clk_detect(struct fpdlink_dev *ub927)
+{
+       unsigned int val;
+       int count, ret;
+
+       mutex_lock(&ub927->lock);
+
+       for (count = 0; count < MAX_I2C_RETRY; count++) {
+               ret = regmap_read(ub927->regmap, UB927_GS_REG, &val);
+               if (!ret && (val & UB927_GS_PCLK_DETECT)) {
+                       dev_info(ub927->dev,
+                                       "LVDS: %d, Serializer LVDS CLK OK!!\n",
+                                       ub927->index);
+                       ub927->pixel_clk_status = detected;
+                       ret = true;
+                       goto done;
+               }
+       }
+       dev_info(ub927->dev,
+                       "LVDS:%d LVDS CLK is not detected at Serializer !!\n",
+                       ub927->index);
+       ub927->pixel_clk_status = not_detected;
+
+done:
+       mutex_unlock(&ub927->lock);
+       if (ret < 0) {
+               dev_info(ub927->dev,
+                               "failed on regmap_read at %s()\n", __func__);
+       }
+       return (ub927->pixel_clk_status ? true : false);
+
+}
+
+static int parse_config_val(struct fpdlink_dev *ub927, struct device_node *np)
+{
+       const u32 *config_property;
+       int len;
+       u8 *config_array;
+       int config_array_size;
+       int i = 0;
+
+       config_property = of_get_property(np, "reg_config", &len);
+       config_array_size = len/sizeof(u32);
+
+       /*config value must be pair of register offset and value */
+       if (!config_property || config_array_size <= 1 || config_array_size%2)
+               return -EINVAL;
+
+       config_array = kcalloc(config_array_size, sizeof(u8), GFP_KERNEL);
+       if (!config_array_size)
+               return -ENOMEM;
+
+       for (i = 0; i < config_array_size; i++)
+               config_array[i] = (u8)be32_to_cpu(config_property[i]);
+
+       ub927->config_array_size = config_array_size;
+       ub927->config_array = config_array;
+       return 0;
+}
+
+static const struct fpdlink_dev_funcs ub927_fpdlink_dev_funcs = {
+       .enable                         = ub927_enable,
+       .reset                          = ub927_reset,
+       .enable_i2c_passthrough         = ub927_enable_i2c_passthrough,
+       .reg_write                      = ub927_reg_write,
+       .link_detect                    = ub927_link_detect,
+       .pixel_clk_detect               = ub927_pixel_clk_detect,
+       .config                         = ub927_update_config,
+};
+
+static void ub927_shutdown(struct i2c_client *client)
+{
+       struct fpdlink_dev *ub927 = i2c_get_clientdata(client);
+
+       ub927_disable(ub927);
+}
+
+static ssize_t link_status_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       struct fpdlink_dev *ub927 = dev_get_drvdata(dev);
+       int ret = 0;
+       int count, status;
+       unsigned int val;
+
+       ret = mutex_lock_interruptible(&ub927->lock);
+       if (ret)
+               return ret;
+
+       ub927->link_status = not_detected;
+       for (count = 0; count < MAX_I2C_RETRY; count++) {
+               usleep_range(10000, 15000);
+               ret = regmap_read(ub927->regmap, UB927_GS_REG, &val);
+               if (!ret && (val & UB927_GS_LINK_DETECT)) {
+                       ub927->link_status = detected;
+                       break;
+               }
+               usleep_range(10000, 15000);
+       }
+       status = ub927->link_status;
+       mutex_unlock(&ub927->lock);
+
+       if (ret < 0) {
+               dev_info(ub927->dev, "failed on regmap_read at %s()\n",
+                               __func__);
+       }
+
+       return snprintf(buf, PAGE_SIZE, "%s\n",
+                       status ? "connected":"disconnected");
+}
+
+static ssize_t pixel_clk_status_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       struct fpdlink_dev *ub927 = dev_get_drvdata(dev);
+       int count, status;
+       int ret = 0;
+       unsigned int val;
+
+       ret = mutex_lock_interruptible(&ub927->lock);
+       if (ret)
+               return ret;
+
+       ub927->pixel_clk_status = not_detected;
+       for (count = 0; count < MAX_I2C_RETRY; count++) {
+               ret = regmap_read(ub927->regmap, UB927_GS_REG, &val);
+               if (!ret && (val & UB927_GS_PCLK_DETECT)) {
+                       ub927->pixel_clk_status = detected;
+                       break;
+               }
+               usleep_range(10000, 15000);
+       }
+
+       status = ub927->pixel_clk_status;
+       mutex_unlock(&ub927->lock);
+
+       if (ret < 0) {
+               dev_info(ub927->dev, "failed on regmap_read at %s()\n",
+                               __func__);
+       }
+       return snprintf(buf, PAGE_SIZE, "%s\n", status ? "on":"off");
+}
+
+static DEVICE_ATTR_RO(link_status);
+static DEVICE_ATTR_RO(pixel_clk_status);
+
+
+static int ub927_probe(struct i2c_client *client,
+               const struct i2c_device_id *id)
+{
+       struct device *dev = &client->dev;
+       struct fpdlink_dev *ub927;
+       struct device_node *node_ptr;
+
+       int ret = 0;
+
+       ub927 = devm_kzalloc(dev, sizeof(*ub927), GFP_KERNEL);
+       if (!ub927)
+               return -ENOMEM;
+
+       ub927->dev = dev;
+       node_ptr = dev->of_node;
+
+       ub927->gpio_power_en = of_get_named_gpio(node_ptr, "power-en-pin", 0);
+       if (ub927->gpio_power_en > 0) {
+               sprintf(ub927->gpio_name, "ub927 %d", ub927->index);
+               if (!gpio_is_valid(ub927->gpio_power_en)) {
+                       dev_err(dev, "invalid gpio for gpio_power_en %s\n",
+                                       ub927->gpio_name);
+                       ret = -ENXIO;
+                       goto done;
+               }
+       }
+
+       ub927->client = client;
+       ub927->regmap = devm_regmap_init_i2c(client, &ub927_regmap_config);
+       if (IS_ERR(ub927->regmap)) {
+               dev_err(dev, "failed to allocate register map\n");
+               ret = PTR_ERR(ub927->regmap);
+               goto done;
+       }
+
+       ub927->bridge.of_node = node_ptr;
+       ub927_disable(ub927);
+
+       mutex_init(&ub927->lock);
+       ub927->funcs = &ub927_fpdlink_dev_funcs;
+       parse_config_val(ub927, node_ptr);
+       i2c_set_clientdata(client, ub927);
+
+       drm_bridge_add(&ub927->bridge);
+
+       device_create_file(dev, &dev_attr_link_status);
+       device_create_file(dev, &dev_attr_pixel_clk_status);
+
+done:
+       if (ret < 0)
+               devm_kfree(&client->dev, ub927);
+       return ret;
+}
+
+static int ub927_remove(struct i2c_client *client)
+{
+       struct fpdlink_dev *ub927 =  i2c_get_clientdata(client);
+
+       drm_bridge_remove(&ub927->bridge);
+       return 0;
+}
+
+static const struct i2c_device_id ub927_id[] = {
+       { "ds90ub927", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, ub927_id);
+
+static const struct of_device_id ub927_match[] = {
+       { .compatible = "ti,ds90ub927" },
+       {},
+};
+MODULE_DEVICE_TABLE(of, ub927_match);
+
+static struct i2c_driver ti_ub927_driver = {
+       .id_table       = ub927_id,
+       .probe          = ub927_probe,
+       .remove         = ub927_remove,
+       .shutdown       = ub927_shutdown,
+       .driver         = {
+       .name           = "ti-ub927",
+       .of_match_table = ub927_match,
+       },
+};
+module_i2c_driver(ti_ub927_driver);
+
+MODULE_AUTHOR("Vince Kim <vince.k....@gmail.com>");
+MODULE_DESCRIPTION("TI UB927 Serializer driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub948.c 
b/drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub948.c
new file mode 100644
index 000000000000..f42130a19533
--- /dev/null
+++ b/drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub948.c
@@ -0,0 +1,333 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TI FPD-LinkIII DS90UB948 driver
+ *
+ * Copyright (C) 2019 Lucid Motors Inc.
+ *
+ * Contact: Vince Kim <vince.k....@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/of_gpio.h>
+#include <drm/drmP.h>
+#include "ti-fpdlink.h"
+
+#define UB948_RESET_REG                                0x01
+#define UB948_RESET_DGTL_RST0                  (1<<2)
+
+#define UB948_GS_REG                           0x1c
+#define UB948_GS_LOCK_DETECT                   (1<<0)
+
+#define UB948_DUAL_CTL1_REG                    0x5b
+
+#define UB948_DUAL_STS_REG                     0x5a
+#define UB948_DUAL_STS_FPD3_LINK_READY         (1<<7)
+
+#define MAX_I2C_RETRY 10
+
+static inline struct fpdlink_dev *
+drm_bridge_to_ub948(struct drm_bridge *bridge)
+{
+       return container_of(bridge, struct fpdlink_dev, bridge);
+}
+
+static inline int regmap_write_fpdlink(struct regmap *map, unsigned int reg,
+                                       unsigned int val)
+{
+       int count = MAX_I2C_RETRY;
+       int ret = -1;
+
+       while (count-- && (ret = regmap_write(map, reg, val)))
+               usleep_range(1000, 1100);
+
+       return ret;
+}
+
+static const struct regmap_config ub948_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 8,
+       .cache_type = REGCACHE_NONE,
+       .max_register = 0xff,
+};
+
+static int ub948_enable(struct fpdlink_dev *ub948)
+{
+       if (gpio_is_valid(ub948->gpio_power_en)) {
+               gpio_set_value(ub948->gpio_power_en, 1);
+       } else {
+               if (ub948->gpio_power_en > 0) {
+                       dev_err(ub948->dev,
+                               "invalid gpio for gpio_disp_en %s\n",
+                               ub948->gpio_name);
+                       return -ENXIO;
+               }
+       }
+       msleep(200);
+       return 0;
+}
+
+static void ub948_disable(struct fpdlink_dev *ub948)
+{
+       if (gpio_is_valid(ub948->gpio_power_en))
+               gpio_set_value(ub948->gpio_power_en, 0);
+}
+
+static int ub948_reset(struct fpdlink_dev *ub948)
+{
+       int ret;
+
+       ret = regmap_write_fpdlink(ub948->regmap,
+                       UB948_RESET_REG, UB948_RESET_DGTL_RST0);
+       msleep(100);
+       if (ret == 0)
+               ub948->detected = true;
+       return ret;
+}
+
+static int ub948_reg_write(struct fpdlink_dev *ub948, u8 reg, u8 val)
+{
+       return regmap_write_fpdlink(ub948->regmap, reg, val);
+}
+
+static int ub948_update_config(struct fpdlink_dev *ub948)
+{
+       int i = 0;
+       int size;
+       u8 *config_array;
+       int ret = 0;
+
+       size = ub948->config_array_size;
+       config_array = ub948->config_array;
+
+       if (!config_array)
+               return 0;
+
+       while (i < size) {
+               ret = regmap_write_fpdlink(ub948->regmap, config_array[i],
+                               config_array[i+1]);
+               if (ret) {
+                       dev_err(ub948->dev,
+                               "%s: failed to update register\n", __func__);
+                       return -EINVAL;
+               }
+               i += 2;
+       }
+       return 0;
+}
+
+static bool ub948_link_detect(struct fpdlink_dev *ub948)
+{
+       unsigned int val;
+       int count, ret;
+
+       if (ub948->detected == false)
+               return false;
+
+       mutex_lock(&ub948->lock);
+       ub948->link_status = not_detected;
+       for (count = 0; count < MAX_I2C_RETRY; count++) {
+               ret = regmap_read(ub948->regmap, UB948_GS_REG, &val);
+
+               if (!ret && (val & UB948_GS_LOCK_DETECT)) {
+                       dev_info(ub948->dev,
+                               "HDMI: %d DeSerializer FPD link ready!\n",
+                               ub948->index);
+                       ub948->link_status = detected;
+                       ret = true;
+                       goto done;
+               }
+               usleep_range(10000, 11000);
+       }
+       dev_info(ub948->dev, "HDMI: %d DeSerializer FPD link failed!!\n",
+                       ub948->index);
+
+done:
+       mutex_unlock(&ub948->lock);
+
+       if (ret < 0)
+               dev_info(ub948->dev, "failed on regmap_read at %s()\n",
+                               __func__);
+
+       return ub948->link_status ? true : false;
+}
+
+static int parse_config_val(struct fpdlink_dev *ub948,
+               struct device_node *node_ptr)
+{
+       const u32 *config_property;
+       int len;
+       u8 *config_array;
+       int config_array_size;
+       int i = 0;
+
+       config_property = of_get_property(node_ptr, "reg_config", &len);
+       config_array_size = len/sizeof(u32);
+
+       /*config value must be pair of register offset and value */
+       if (!config_property || config_array_size <= 1 || config_array_size%2)
+               return -EINVAL;
+
+       config_array = kcalloc(config_array_size, sizeof(u8), GFP_KERNEL);
+       if (!config_array_size)
+               return -ENOMEM;
+
+       for (i = 0; i < config_array_size; i++)
+               config_array[i] = (u8)be32_to_cpu(config_property[i]);
+
+       ub948->config_array_size = config_array_size;
+       ub948->config_array = config_array;
+       return 0;
+}
+
+static const struct fpdlink_dev_funcs ub948_fpdlink_dev_funcs = {
+       .enable                         = ub948_enable,
+       .reset                          = ub948_reset,
+       .reg_write                      = ub948_reg_write,
+       .link_detect                    = ub948_link_detect,
+       .config                         = ub948_update_config,
+};
+
+static void ub948_shutdown(struct i2c_client *client)
+{
+       struct fpdlink_dev *ub948 = i2c_get_clientdata(client);
+
+       ub948_disable(ub948);
+}
+
+static ssize_t lock_status_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       struct fpdlink_dev *ub948 = dev_get_drvdata(dev);
+       int ret = 0;
+       int status;
+       unsigned int val;
+       int count;
+
+       if (ub948->detected == false)
+               return snprintf(buf, PAGE_SIZE, "%s\n", "off");
+
+       ret = mutex_lock_interruptible(&ub948->lock);
+       if (ret)
+               return ret;
+
+       ub948->link_status = not_detected;
+       for (count = 0; count < MAX_I2C_RETRY; count++) {
+               ret = regmap_read(ub948->regmap, UB948_GS_REG, &val);
+               if (!ret && (val & UB948_GS_LOCK_DETECT)) {
+                       ub948->link_status = detected;
+                       break;
+               }
+               usleep_range(10000, 11000);
+       }
+       status = ub948->link_status;
+       mutex_unlock(&ub948->lock);
+
+       if (ret < 0) {
+               dev_info(ub948->dev, "failed on regmap_read at %s()\n",
+                               __func__);
+       }
+
+       return snprintf(buf, PAGE_SIZE, "%s\n", status ? "on":"off");
+}
+static DEVICE_ATTR_RO(lock_status);
+
+static int ub948_probe(struct i2c_client *client,
+               const struct i2c_device_id *id)
+{
+       struct device *dev = &client->dev;
+       struct fpdlink_dev *ub948;
+       struct device_node *node_ptr;
+
+       int ret = 0;
+
+       ub948 = devm_kzalloc(dev, sizeof(*ub948), GFP_KERNEL);
+       if (!ub948)
+               return -ENOMEM;
+
+       ub948->dev = dev;
+       node_ptr = dev->of_node;
+
+       ub948->gpio_power_en = of_get_named_gpio(node_ptr, "power-en-pin", 0);
+       if (ub948->gpio_power_en > 0) {
+               sprintf(ub948->gpio_name, "ub948 %d", ub948->index);
+               if (!gpio_is_valid(ub948->gpio_power_en)) {
+                       dev_err(dev, "invalid gpio for gpio_power_en %s\n",
+                                       ub948->gpio_name);
+                       ret = -ENXIO;
+                       goto done;
+               }
+       }
+
+       ub948->client = client;
+       ub948->regmap = devm_regmap_init_i2c(client, &ub948_regmap_config);
+       if (IS_ERR(ub948->regmap)) {
+               dev_err(dev, "failed to allocate register map\n");
+               ret = PTR_ERR(ub948->regmap);
+               goto done;
+       }
+
+       mutex_init(&ub948->lock);
+       ub948->bridge.of_node = node_ptr;
+       ub948_disable(ub948);
+
+       ub948->funcs = &ub948_fpdlink_dev_funcs;
+       parse_config_val(ub948, node_ptr);
+       i2c_set_clientdata(client, ub948);
+
+       drm_bridge_add(&ub948->bridge);
+       device_create_file(dev, &dev_attr_lock_status);
+       /*
+        * we don't know if deserializer is attached until serializer is ready.
+        */
+       ub948->detected = false;
+
+done:
+       return ret;
+}
+
+static int ub948_remove(struct i2c_client *client)
+{
+       struct fpdlink_dev *ub948 =  i2c_get_clientdata(client);
+
+       drm_bridge_remove(&ub948->bridge);
+       return 0;
+}
+
+static const struct i2c_device_id ub948_id[] = {
+       { "ds90ub948", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, ub948_id);
+
+static const struct of_device_id ub948_match[] = {
+       { .compatible = "ti,ds90ub948" },
+       {},
+};
+MODULE_DEVICE_TABLE(of, ub948_match);
+
+static struct i2c_driver ti_ub948_driver = {
+       .id_table       = ub948_id,
+       .probe          = ub948_probe,
+       .remove         = ub948_remove,
+       .shutdown       = ub948_shutdown,
+       .driver         = {
+       .name           = "ti-ub948",
+       .of_match_table = ub948_match,
+       },
+};
+module_i2c_driver(ti_ub948_driver);
+
+MODULE_AUTHOR("Vince Kim <vince.k....@gmail.com>");
+MODULE_DESCRIPTION("TI UB948 Serializer driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub949.c 
b/drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub949.c
new file mode 100644
index 000000000000..bb99d296fbb8
--- /dev/null
+++ b/drivers/gpu/drm/bridge/ti-fpdlink/ti-ds90ub949.c
@@ -0,0 +1,435 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TI FPD-LinkIII DS90UB949 driver
+ *
+ * Copyright (C) 2019 Lucid Motors Inc.
+ *
+ * Contact: Vince Kim <vince.k....@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/of_gpio.h>
+#include <drm/drmP.h>
+#include "ti-fpdlink.h"
+
+#define UB949_RESET_REG                                0x01
+#define UB949_RESET_HDMI_RST                   (1<<4)
+#define UB949_RESET_DGTL_RST1                  (1<<1)
+
+#define UB949_GS_REG                           0x0c
+#define UB949_GS_BIST_CRC_ERROR                        (1<<3)
+#define UB949_GS_TMDS_CLK_DETECT               (1<<2)
+#define UB949_GS_DES_CRC_ERROR                 (1<<1)
+#define UB949_GS_LINK_DETECT                   (1<<0)
+
+#define UB949_I2C_CTRL_REG                     0x17
+#define UB949_I2C_CTRL_PASS_ALL                        (1<<7)
+
+#define UB949_DUAL_STS_REG                     0x5a
+#define UB949_DUAL_STS_FPD3_LINK_READY         (1<<7)
+#define UB949_DUAL_STS_FPD3_TX_STS             (1<<6)
+
+#define UB949_DUAL_CTL1_REG                    0x5b
+#define UB949_DUAL_CTL2_REG                    0x5c
+#define UB949_HDMI_FREQ                                0x5f
+
+#define MAX_I2C_RETRY 10
+
+
+static inline struct fpdlink_dev *
+drm_bridge_to_ub949(struct drm_bridge *bridge)
+{
+       return container_of(bridge, struct fpdlink_dev, bridge);
+}
+
+static inline int regmap_write_fpdlink(struct regmap *map, unsigned int reg,
+                                       unsigned int val)
+{
+       int count = MAX_I2C_RETRY;
+       int ret = -1;
+
+       while (count-- && (ret = regmap_write(map, reg, val)))
+               usleep_range(1000, 1100);
+
+       return ret;
+}
+
+static const struct regmap_config ub949_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 8,
+       .cache_type = REGCACHE_NONE,
+       .max_register = 0xff,
+};
+
+static int ub949_enable(struct fpdlink_dev *ub949)
+{
+       if (gpio_is_valid(ub949->gpio_power_en)) {
+               gpio_set_value(ub949->gpio_power_en, 1);
+       } else {
+               if (ub949->gpio_power_en > 0) {
+                       dev_err(ub949->dev,
+                               "invalid gpio for gpio_disp_en %s\n",
+                               ub949->gpio_name);
+                       return -ENXIO;
+               }
+       }
+
+       msleep(200);
+       return 0;
+}
+
+static void ub949_disable(struct fpdlink_dev *ub949)
+{
+       regmap_write_fpdlink(ub949->regmap, UB949_RESET_REG,
+                       (UB949_RESET_HDMI_RST|UB949_RESET_DGTL_RST1));
+}
+
+static int ub949_reset(struct fpdlink_dev *ub949)
+{
+       int ret;
+
+       ret = regmap_write_fpdlink(ub949->regmap, UB949_RESET_REG,
+                       (UB949_RESET_HDMI_RST|UB949_RESET_DGTL_RST1));
+       usleep_range(10000, 11000);
+
+       return ret;
+}
+
+static int ub949_enable_i2c_passthrough(struct fpdlink_dev *ub949)
+{
+       int ret;
+       unsigned int val;
+
+       ret = regmap_read(ub949->regmap, UB949_I2C_CTRL_REG, &val);
+       if (ret < 0) {
+               dev_err(ub949->dev, "failed on regmap_read at %s()\n",
+                               __func__);
+               return ret;
+       }
+
+       ret = regmap_write_fpdlink(ub949->regmap, UB949_I2C_CTRL_REG,
+                       (val | UB949_I2C_CTRL_PASS_ALL));
+       msleep(100);
+
+       return ret;
+}
+
+static int ub949_reg_write(struct fpdlink_dev *ub949, u8 reg, u8 val)
+{
+       return regmap_write_fpdlink(ub949->regmap, reg, val);
+}
+
+static int ub949_update_config(struct fpdlink_dev *ub949)
+{
+       int i = 0;
+       int size;
+       u8 *config_array;
+       int ret = 0;
+
+       size = ub949->config_array_size;
+       config_array = ub949->config_array;
+
+       if (!config_array)
+               return 0;
+
+       while (i < size) {
+               ret = regmap_write_fpdlink(ub949->regmap, config_array[i],
+                               config_array[i+1]);
+               if (ret) {
+                       dev_err(ub949->dev,
+                               "%s: failed to update register\n", __func__);
+                       return -EINVAL;
+               }
+               i += 2;
+       }
+
+       return 0;
+}
+
+static bool ub949_link_detect(struct fpdlink_dev *ub949)
+{
+       unsigned int val, val2;
+       int count, ret;
+
+       mutex_lock(&ub949->lock);
+       ub949->link_status = not_detected;
+
+       for (count = 0; count < MAX_I2C_RETRY; count++) {
+               usleep_range(10000, 11000);
+               ret = regmap_read(ub949->regmap, UB949_GS_REG, &val);
+               ret += regmap_read(ub949->regmap, UB949_DUAL_STS_REG, &val2);
+               if (!ret && (val & UB949_GS_LINK_DETECT) &&
+                               (val2 & UB949_DUAL_STS_FPD3_LINK_READY)) {
+                       dev_info(ub949->dev,
+                                       "HDMI: %d Serializer FPD link ready!\n",
+                                       ub949->index);
+                       ub949->link_status = detected;
+                       ret = true;
+                       goto done;
+               }
+       }
+       dev_info(ub949->dev,
+                       "HDMI:%d Serializer FPD link failed!!\n", ub949->index);
+
+done:
+       mutex_unlock(&ub949->lock);
+
+       if (ret < 0) {
+               dev_info(ub949->dev,
+                               "failed on regmap_read at %s()\n", __func__);
+       }
+
+       return (ub949->link_status ? true : false);
+}
+
+static bool ub949_pixel_clk_detect(struct fpdlink_dev *ub949)
+{
+       unsigned int val;
+       int count, ret;
+
+       mutex_lock(&ub949->lock);
+
+       for (count = 0; count < 1; count++) {
+               ret = regmap_read(ub949->regmap, UB949_HDMI_FREQ, &val);
+               if (!ret && val) {
+                       dev_info(ub949->dev,
+                                       "HDMI: %d,  Serializer HDMI CLK OK!!\n",
+                                       ub949->index);
+                       ub949->pixel_clk_status = detected;
+                       ret = true;
+                       goto done;
+               }
+       }
+       dev_info(ub949->dev,
+                       "HDMI:%d HDMI CLK is not detected at Serializer !!\n",
+                       ub949->index);
+       ub949->pixel_clk_status = not_detected;
+
+done:
+       mutex_unlock(&ub949->lock);
+
+       if (ret < 0)
+               dev_info(ub949->dev,
+                               "failed on regmap_read at %s()\n", __func__);
+
+       return ub949->pixel_clk_status ? true : false;
+
+}
+
+static int parse_config_val(struct fpdlink_dev *ub949,
+               struct device_node *node_ptr)
+{
+       const u32 *config_property;
+       int len;
+       u8 *config_array;
+       int config_array_size;
+       int i = 0;
+
+       config_property = of_get_property(node_ptr, "reg_config", &len);
+       config_array_size = len/sizeof(u32);
+
+       /*config value must be a pair of register offset and value */
+       if (!config_property || config_array_size <= 1 || config_array_size%2)
+               return -EINVAL;
+
+       config_array = kcalloc(config_array_size, sizeof(u8), GFP_KERNEL);
+       if (!config_array_size)
+               return -ENOMEM;
+
+       for (i = 0; i < config_array_size; i++)
+               config_array[i] = (u8)be32_to_cpu(config_property[i]);
+
+       ub949->config_array_size = config_array_size;
+       ub949->config_array = config_array;
+       return 0;
+}
+
+static const struct fpdlink_dev_funcs ub949_fpdlink_dev_funcs = {
+       .enable                         = ub949_enable,
+       .reset                          = ub949_reset,
+       .enable_i2c_passthrough         = ub949_enable_i2c_passthrough,
+       .reg_write                      = ub949_reg_write,
+       .link_detect                    = ub949_link_detect,
+       .pixel_clk_detect               = ub949_pixel_clk_detect,
+       .config                         = ub949_update_config,
+};
+
+static void ub949_shutdown(struct i2c_client *client)
+{
+       struct fpdlink_dev *ub949 = i2c_get_clientdata(client);
+
+       ub949_disable(ub949);
+}
+
+static ssize_t link_status_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       struct fpdlink_dev *ub949 = dev_get_drvdata(dev);
+       int status, ret;
+       unsigned int val, val2;
+       int count;
+
+       ret = mutex_lock_interruptible(&ub949->lock);
+       if (ret)
+               return ret;
+
+       ub949->link_status = not_detected;
+
+       for (count = 0; count < MAX_I2C_RETRY; count++) {
+               ret = regmap_read(ub949->regmap, UB949_GS_REG, &val);
+               ret += regmap_read(ub949->regmap, UB949_DUAL_STS_REG, &val2);
+               if (!ret && (val & UB949_GS_LINK_DETECT)
+                        && (val2 & UB949_DUAL_STS_FPD3_LINK_READY)) {
+                       ub949->link_status = detected;
+                       break;
+               }
+               usleep_range(10000, 11000);
+       }
+       status = ub949->link_status;
+       mutex_unlock(&ub949->lock);
+
+       if (ret < 0)
+               dev_err(ub949->dev,
+                               "failed on regmap_read at %s()\n", __func__);
+
+       return snprintf(buf, PAGE_SIZE, "%s\n",
+                       status ? "connected":"disconnected");
+}
+
+static ssize_t pixel_clk_status_show(struct device *dev,
+               struct device_attribute *attr, char *buf)
+{
+       struct fpdlink_dev *ub949 = dev_get_drvdata(dev);
+       int status, ret;
+       unsigned int val, val2;
+       int count;
+
+       ret = mutex_lock_interruptible(&ub949->lock);
+       if (ret)
+               return ret;
+
+       ub949->pixel_clk_status = not_detected;
+       for (count = 0; count < MAX_I2C_RETRY; count++) {
+               ret = regmap_read(ub949->regmap, UB949_HDMI_FREQ, &val);
+               ret += regmap_read(ub949->regmap, UB949_GS_REG, &val2);
+               if (!ret && val && (val2 & UB949_GS_TMDS_CLK_DETECT)) {
+                       ub949->pixel_clk_status = detected;
+                       break;
+               }
+               usleep_range(10000, 11000);
+       }
+       status = ub949->pixel_clk_status;
+       mutex_unlock(&ub949->lock);
+
+       if (ret < 0)
+               dev_err(ub949->dev,
+                               "failed on regmap_read at %s()\n", __func__);
+
+       return snprintf(buf, PAGE_SIZE, "%s\n", status ? "on":"off");
+}
+
+static DEVICE_ATTR_RO(link_status);
+static DEVICE_ATTR_RO(pixel_clk_status);
+
+static int ub949_probe(struct i2c_client *client,
+               const struct i2c_device_id *id)
+{
+       struct device *dev = &client->dev;
+       struct fpdlink_dev *ub949;
+       struct device_node *node_ptr;
+
+       int ret = 0;
+
+       ub949 = devm_kzalloc(dev, sizeof(*ub949), GFP_KERNEL);
+       if (!ub949)
+               return -ENOMEM;
+
+       ub949->dev = dev;
+       node_ptr = dev->of_node;
+
+       ub949->gpio_power_en = of_get_named_gpio(node_ptr, "power-en-pin", 0);
+       if (ub949->gpio_power_en > 0) {
+               sprintf(ub949->gpio_name, "ub949 %d", ub949->index);
+               if (!gpio_is_valid(ub949->gpio_power_en)) {
+                       dev_err(dev, "invalid gpio for gpio_power_en %s\n",
+                                       ub949->gpio_name);
+                       ret = -ENXIO;
+                       goto done;
+               }
+       }
+
+       ub949->client = client;
+       ub949->regmap = devm_regmap_init_i2c(client, &ub949_regmap_config);
+       if (IS_ERR(ub949->regmap)) {
+               dev_err(dev, "failed to allocate register map\n");
+               ret = PTR_ERR(ub949->regmap);
+               goto done;
+       }
+
+       mutex_init(&ub949->lock);
+
+       ub949->bridge.of_node = node_ptr;
+       ub949_disable(ub949);
+
+       ub949->funcs = &ub949_fpdlink_dev_funcs;
+       parse_config_val(ub949, node_ptr);
+       i2c_set_clientdata(client, ub949);
+
+       drm_bridge_add(&ub949->bridge);
+
+       device_create_file(dev, &dev_attr_link_status);
+       device_create_file(dev, &dev_attr_pixel_clk_status);
+
+done:
+       if (ret < 0)
+               devm_kfree(&client->dev, ub949);
+
+       return ret;
+}
+
+static int ub949_remove(struct i2c_client *client)
+{
+       struct fpdlink_dev *ub949 =  i2c_get_clientdata(client);
+
+       drm_bridge_remove(&ub949->bridge);
+       return 0;
+}
+
+static const struct i2c_device_id ub949_id[] = {
+       { "ds90ub949", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, ub949_id);
+
+static const struct of_device_id ub949_match[] = {
+       { .compatible = "ti,ds90ub949" },
+       {},
+};
+MODULE_DEVICE_TABLE(of, ub949_match);
+
+static struct i2c_driver ti_ub949_driver = {
+       .id_table       = ub949_id,
+       .probe          = ub949_probe,
+       .remove         = ub949_remove,
+       .shutdown       = ub949_shutdown,
+       .driver         = {
+               .name           = "ti-ub949",
+               .of_match_table = ub949_match,
+       },
+};
+module_i2c_driver(ti_ub949_driver);
+
+MODULE_AUTHOR("Vince Kim <vince.k....@gmail.com>");
+MODULE_DESCRIPTION("TI UB949 Serializer driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/gpu/drm/bridge/ti-fpdlink/ti-fpdlink.c 
b/drivers/gpu/drm/bridge/ti-fpdlink/ti-fpdlink.c
new file mode 100644
index 000000000000..fa4cd5806f19
--- /dev/null
+++ b/drivers/gpu/drm/bridge/ti-fpdlink/ti-fpdlink.c
@@ -0,0 +1,396 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TI FPD-LinkIII interface bridge driver
+ *
+ * Copyright (C) 2019 Lucid Motors Inc.
+ *
+ * Contact: Vince Kim <vince.k....@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_probe_helper.h>
+#include <linux/of_gpio.h>
+#include "ti-fpdlink.h"
+
+struct fpdlink {
+       struct drm_bridge       bridge;
+       struct drm_connector    connector;
+
+       struct fpdlink_dev      *serializer;
+       struct fpdlink_dev      *deserializer;
+       struct device_node      *fpdlink_node;
+       struct mutex lock;
+
+       unsigned int index;
+       enum clk_status pixel_clk_status;
+       enum clk_status link_status;
+       bool enabled;
+};
+
+
+static inline struct fpdlink *
+drm_bridge_to_fpdlink(struct drm_bridge *bridge)
+{
+       return container_of(bridge, struct fpdlink, bridge);
+}
+
+static inline struct fpdlink *
+drm_connector_to_fpdlink(struct drm_connector *connector)
+{
+       return container_of(connector, struct fpdlink, connector);
+}
+
+static int fpdlink_dev_enable(struct fpdlink_dev *dev)
+{
+       int ret;
+
+       if (!dev)
+               return -EINVAL;
+       if (!dev->funcs)
+               return -EINVAL;
+       if (!dev->funcs->enable)
+               return -EINVAL;
+
+       ret = dev->funcs->enable(dev);
+
+       return ret;
+}
+
+static int fpdlink_dev_reset(struct fpdlink_dev *dev)
+{
+       int ret;
+
+       if (!dev)
+               return -EINVAL;
+       if (!dev->funcs)
+               return -EINVAL;
+       if (!dev->funcs->reset)
+               return -EINVAL;
+
+       ret = dev->funcs->reset(dev);
+       return ret;
+}
+
+static int fpdlink_dev_enable_i2c_passthrough(struct fpdlink_dev *dev)
+{
+       int ret;
+
+       if (!dev)
+               return -EINVAL;
+       if (!dev->funcs)
+               return -EINVAL;
+       if (!dev->funcs->enable_i2c_passthrough)
+               return -EINVAL;
+
+       ret = dev->funcs->enable_i2c_passthrough(dev);
+       return ret;
+}
+
+static bool fpdlink_dev_link_detect(struct fpdlink_dev *dev)
+{
+       bool ret;
+
+       if (!dev)
+               return -EINVAL;
+       if (!dev->funcs)
+               return -EINVAL;
+       if (!dev->funcs->link_detect)
+               return -EINVAL;
+
+       ret = dev->funcs->link_detect(dev);
+       return ret;
+}
+
+static bool fpdlink_dev_pixel_clk_detect(struct fpdlink_dev *dev)
+{
+       bool ret;
+
+       if (!dev)
+               return -EINVAL;
+       if (!dev->funcs)
+               return -EINVAL;
+       if (!dev->funcs->pixel_clk_detect)
+               return -EINVAL;
+
+       ret = dev->funcs->pixel_clk_detect(dev);
+       return ret;
+}
+
+static int fpdlink_dev_config(struct fpdlink_dev *dev)
+{
+       int ret;
+
+       if (!dev)
+               return -EINVAL;
+       if (!dev->funcs)
+               return -EINVAL;
+       if (!dev->funcs->config)
+               return -EINVAL;
+
+       ret = dev->funcs->config(dev);
+       return ret;
+}
+
+static enum drm_connector_status
+fpdlink_connector_detect(struct drm_connector *connector, bool force)
+{
+       struct fpdlink *fpdlink_bridge = drm_connector_to_fpdlink(connector);
+
+       if (fpdlink_bridge->link_status == detected)
+               return connector_status_connected;
+
+       return connector_status_disconnected;
+}
+
+static const struct drm_connector_funcs fpdlink_con_funcs = {
+       .detect                 = fpdlink_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 void fpdlink_pre_enable(struct drm_bridge *bridge)
+{
+       struct fpdlink *fpdlink_bridge = drm_bridge_to_fpdlink(bridge);
+
+       struct fpdlink_dev *serializer = fpdlink_bridge->serializer;
+       struct fpdlink_dev *deserializer = fpdlink_bridge->deserializer;
+       int ret = 0;
+
+       mutex_lock(&fpdlink_bridge->lock);
+
+       if (fpdlink_bridge->link_status == detected)
+               goto done;
+
+       fpdlink_dev_enable(deserializer);
+       fpdlink_dev_enable(serializer);
+       fpdlink_dev_reset(serializer);
+       fpdlink_dev_enable_i2c_passthrough(serializer);
+       ret = fpdlink_dev_reset(deserializer);
+       if (ret != 0) {
+               fpdlink_bridge->connector.status =
+                               connector_status_disconnected;
+               DRM_INFO("Not able to detect Deserializer at %pOF\n",
+                               fpdlink_bridge->fpdlink_node);
+               goto done;
+       }
+
+       ret = fpdlink_dev_link_detect(serializer);
+       if (ret != true) {
+               fpdlink_bridge->connector.status =
+                               connector_status_disconnected;
+               goto done;
+       }
+
+       fpdlink_bridge->link_status = detected;
+       fpdlink_bridge->pixel_clk_status = not_detected;
+       fpdlink_bridge->connector.status = connector_status_connected;
+done:
+       mutex_unlock(&fpdlink_bridge->lock);
+}
+
+static void fpdlink_enable(struct drm_bridge *bridge)
+{
+       struct fpdlink *fpdlink_bridge = drm_bridge_to_fpdlink(bridge);
+       int ret = 0;
+       struct fpdlink_dev *serializer = fpdlink_bridge->serializer;
+       struct fpdlink_dev *deserializer = fpdlink_bridge->deserializer;
+
+       mutex_lock(&fpdlink_bridge->lock);
+
+       if (fpdlink_bridge->link_status == not_detected) {
+               fpdlink_bridge->connector.status =
+                               connector_status_disconnected;
+               fpdlink_bridge->pixel_clk_status = not_detected;
+               goto done;
+       }
+
+       if (fpdlink_bridge->enabled)
+               goto done;
+
+       ret = fpdlink_dev_pixel_clk_detect(serializer);
+
+       if (ret != true) {
+               fpdlink_bridge->connector.status =
+                               connector_status_disconnected;
+               fpdlink_bridge->pixel_clk_status = not_detected;
+               pr_err("pixel_clk_status not detected\n");
+               goto done;
+       }
+
+       fpdlink_bridge->pixel_clk_status = detected;
+       fpdlink_bridge->connector.status = connector_status_connected;
+       fpdlink_dev_config(serializer);
+       fpdlink_dev_config(deserializer);
+       fpdlink_bridge->enabled = 1;
+
+done:
+       mutex_unlock(&fpdlink_bridge->lock);
+}
+
+static int fpdlink_get_modes(struct drm_connector *connector)
+{
+       struct fpdlink *fpdlink_bridge = drm_connector_to_fpdlink(connector);
+
+       if (fpdlink_bridge->enabled == 0)
+               fpdlink_enable(&fpdlink_bridge->bridge);
+
+       return 0;
+}
+static const struct drm_connector_helper_funcs fpdlink_con_helper_funcs = {
+       .get_modes      = fpdlink_get_modes,
+};
+
+
+static int fpdlink_attach(struct drm_bridge *bridge)
+{
+       struct fpdlink *fpdlink_bridge = drm_bridge_to_fpdlink(bridge);
+       struct device_node *fpdlink_node = bridge->of_node;
+       struct device_node *serializer_node;
+       struct device_node *deserializer_node;
+       struct drm_bridge *serializer_bridge = NULL;
+       struct drm_bridge *deserializer_bridge = NULL;
+       struct drm_connector *connector;
+       int ret;
+
+       if (!bridge->encoder) {
+               DRM_ERROR("Missing encoder\n");
+               return -ENODEV;
+       }
+       connector = dev_get_drvdata(bridge->dev->dev);
+       fpdlink_node = fpdlink_bridge->fpdlink_node;
+
+       drm_connector_helper_add(&fpdlink_bridge->connector,
+                                &fpdlink_con_helper_funcs);
+
+       ret = drm_connector_init(bridge->dev, &fpdlink_bridge->connector,
+                                &fpdlink_con_funcs, DRM_MODE_CONNECTOR_VGA);
+       if (ret) {
+               DRM_ERROR("Failed to initialize connector\n");
+               return ret;
+       }
+
+       drm_connector_attach_encoder(&fpdlink_bridge->connector,
+                                         bridge->encoder);
+
+       serializer_node = of_parse_phandle(fpdlink_node,
+                                          "fpdlink-serializer-i2c-handle", 0);
+       if (!serializer_node) {
+               DRM_INFO("failed to find fpdlink-serializer-i2c-handle node at 
%pOF\n",
+                               fpdlink_node);
+               return -ENODEV;
+       }
+
+       serializer_bridge = of_drm_find_bridge(serializer_node);
+
+
+       if (!serializer_bridge) {
+               DRM_INFO("failed to find serializer bridge for %pOF\n",
+                               serializer_node);
+               return -ENODEV;
+       }
+
+       fpdlink_bridge->serializer =
+                               drm_bridge_to_fpdlink_dev(serializer_bridge);
+       fpdlink_bridge->serializer->index = bridge->encoder->index;
+
+       deserializer_node = of_parse_phandle(fpdlink_node,
+                       "fpdlink-deserializer-i2c-handle", 0);
+       if (!deserializer_node) {
+               DRM_INFO("failed to find fpdlink-deserializer-i2c-handle node 
at %pOF\n",
+                               fpdlink_node);
+               return -ENODEV;
+       }
+
+       deserializer_bridge = of_drm_find_bridge(deserializer_node);
+       if (!deserializer_bridge) {
+               DRM_INFO("failed to find deserializer bridge for %pOF\n",
+                               deserializer_node);
+               return -ENODEV;
+       }
+
+       fpdlink_bridge->deserializer =
+                               drm_bridge_to_fpdlink_dev(deserializer_bridge);
+       fpdlink_bridge->deserializer->index = bridge->encoder->index;
+       fpdlink_bridge->index = bridge->encoder->index;
+       fpdlink_bridge->link_status = not_detected;
+       fpdlink_bridge->pixel_clk_status = not_detected;
+       return ret;
+}
+
+static const struct drm_bridge_funcs fpdlink_bridge_funcs = {
+       .attach         = fpdlink_attach,
+       .pre_enable     = fpdlink_pre_enable,
+       .enable         = fpdlink_enable,
+};
+
+
+
+static int fpdlink_probe(struct platform_device *pdev)
+{
+       struct fpdlink *fpdlink_bridge;
+       int gpio_pin;
+       struct device_node *np;
+
+       fpdlink_bridge = devm_kzalloc(&pdev->dev, sizeof(*fpdlink_bridge),
+                                       GFP_KERNEL);
+       if (!fpdlink_bridge)
+               return -ENOMEM;
+
+       mutex_init(&fpdlink_bridge->lock);
+
+
+       platform_set_drvdata(pdev, fpdlink_bridge);
+
+       fpdlink_bridge->bridge.funcs = &fpdlink_bridge_funcs;
+       np = pdev->dev.of_node;
+       fpdlink_bridge->bridge.of_node = np;
+       fpdlink_bridge->fpdlink_node = np;
+
+       gpio_pin = of_get_named_gpio(np, "disp-en-pin", 0);
+
+       drm_bridge_add(&fpdlink_bridge->bridge);
+       return 0;
+}
+
+static int fpdlink_remove(struct platform_device *pdev)
+{
+       struct fpdlink *fpdlink_bridge = platform_get_drvdata(pdev);
+
+       drm_bridge_remove(&fpdlink_bridge->bridge);
+       return 0;
+}
+
+static const struct of_device_id fpdlink_match[] = {
+       { .compatible = "ti,fpdlink" },
+       {},
+};
+MODULE_DEVICE_TABLE(of, fpdlink_match);
+
+static struct platform_driver ti_fpdlink_driver = {
+       .probe  = fpdlink_probe,
+       .remove = fpdlink_remove,
+       .driver         = {
+               .name           = "ti-fpdlink",
+               .of_match_table = fpdlink_match,
+       },
+};
+module_platform_driver(ti_fpdlink_driver);
+
+MODULE_AUTHOR("Vince Kim <vince.k....@gmail.com>");
+MODULE_DESCRIPTION("TI FPDlink driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/gpu/drm/bridge/ti-fpdlink/ti-fpdlink.h 
b/drivers/gpu/drm/bridge/ti-fpdlink/ti-fpdlink.h
new file mode 100644
index 000000000000..073d4b4601f3
--- /dev/null
+++ b/drivers/gpu/drm/bridge/ti-fpdlink/ti-fpdlink.h
@@ -0,0 +1,70 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * TI FPD-LinkIII interface bridge driver header file
+ *
+ * Copyright (C) 2019 Lucid Motors Inc.
+ *
+ * Contact: Vince Kim <vince.k....@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __TI_FPDLINK_H__
+#define __TI_FPDLINK_H__
+#include <linux/list.h>
+#include <linux/ctype.h>
+#include <drm/drm_mode_object.h>
+#include <drm/drm_modes.h>
+
+struct fpdlink_dev;
+
+enum clk_status {
+       not_detected = 0,
+       detected = 1,
+};
+
+struct fpdlink_dev_funcs {
+       int (*enable)(struct fpdlink_dev *dev);
+       void (*disable)(struct fpdlink_dev *dev);
+       int (*reset)(struct fpdlink_dev *dev);
+       int (*enable_i2c_passthrough)(struct fpdlink_dev *dev);
+       bool (*link_detect)(struct fpdlink_dev *dev);
+       bool (*pixel_clk_detect)(struct fpdlink_dev *dev);
+       int (*config)(struct fpdlink_dev *dev);
+       int (*reg_write)(struct fpdlink_dev *dev, u8 reg, u8 val);
+};
+
+struct fpdlink_dev {
+       struct drm_bridge       bridge;
+       struct drm_connector    connector;
+       struct device           *dev;
+       struct i2c_client       *client;
+       struct regmap           *regmap;
+       struct mutex            lock;
+
+       const struct fpdlink_dev_funcs *funcs;
+
+       char gpio_name[20];
+       unsigned int index;
+       bool    detected;
+       int gpio_power_en;
+       enum clk_status pixel_clk_status;
+       enum clk_status link_status;
+       int config_array_size;
+       u8 *config_array;
+};
+
+static inline struct fpdlink_dev *
+drm_bridge_to_fpdlink_dev(struct drm_bridge *bridge)
+{
+       return container_of(bridge, struct fpdlink_dev, bridge);
+}
+#endif
-- 
2.17.1

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