media: i2c: add DS90UB913 driver
authorTomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Mon, 19 Jun 2023 12:22:11 +0000 (14:22 +0200)
committerMauro Carvalho Chehab <mchehab@kernel.org>
Fri, 14 Jul 2023 11:19:31 +0000 (13:19 +0200)
Add driver for TI DS90UB913 FPD-Link III Serializer.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
drivers/media/i2c/Kconfig
drivers/media/i2c/Makefile
drivers/media/i2c/ds90ub913.c [new file with mode: 0644]

index 8e774c3..e40510d 100644 (file)
@@ -1631,6 +1631,19 @@ endmenu
 
 menu "Video serializers and deserializers"
 
+config VIDEO_DS90UB913
+       tristate "TI DS90UB913 FPD-Link III Serializer"
+       depends on OF && I2C && VIDEO_DEV && COMMON_CLK
+       select I2C_ATR
+       select MEDIA_CONTROLLER
+       select GPIOLIB
+       select REGMAP_I2C
+       select V4L2_FWNODE
+       select VIDEO_V4L2_SUBDEV_API
+       help
+         Device driver for the Texas Instruments DS90UB913
+         FPD-Link III Serializer.
+
 config VIDEO_DS90UB960
        tristate "TI FPD-Link III/IV Deserializers"
        depends on OF && I2C && VIDEO_DEV && COMMON_CLK
index 0da487e..c250752 100644 (file)
@@ -28,6 +28,7 @@ obj-$(CONFIG_VIDEO_CS3308) += cs3308.o
 obj-$(CONFIG_VIDEO_CS5345) += cs5345.o
 obj-$(CONFIG_VIDEO_CS53L32A) += cs53l32a.o
 obj-$(CONFIG_VIDEO_CX25840) += cx25840/
+obj-$(CONFIG_VIDEO_DS90UB913) += ds90ub913.o
 obj-$(CONFIG_VIDEO_DS90UB960) += ds90ub960.o
 obj-$(CONFIG_VIDEO_DW9714) += dw9714.o
 obj-$(CONFIG_VIDEO_DW9768) += dw9768.o
diff --git a/drivers/media/i2c/ds90ub913.c b/drivers/media/i2c/ds90ub913.c
new file mode 100644 (file)
index 0000000..203f7cc
--- /dev/null
@@ -0,0 +1,906 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for the Texas Instruments DS90UB913 video serializer
+ *
+ * Based on a driver from Luca Ceresoli <luca@lucaceresoli.net>
+ *
+ * Copyright (c) 2019 Luca Ceresoli <luca@lucaceresoli.net>
+ * Copyright (c) 2023 Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/fwnode.h>
+#include <linux/gpio/driver.h>
+#include <linux/i2c-atr.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+
+#include <media/i2c/ds90ub9xx.h>
+#include <media/v4l2-subdev.h>
+
+#define UB913_PAD_SINK                 0
+#define UB913_PAD_SOURCE               1
+
+/*
+ * UB913 has 4 gpios, but gpios 3 and 4 are reserved for external oscillator
+ * mode. Thus we only support 2 gpios for now.
+ */
+#define UB913_NUM_GPIOS                        2
+
+#define UB913_REG_RESET_CTL                    0x01
+#define UB913_REG_RESET_CTL_DIGITAL_RESET_1    BIT(1)
+#define UB913_REG_RESET_CTL_DIGITAL_RESET_0    BIT(0)
+
+#define UB913_REG_GENERAL_CFG                  0x03
+#define UB913_REG_GENERAL_CFG_CRC_ERR_RESET    BIT(5)
+#define UB913_REG_GENERAL_CFG_PCLK_RISING      BIT(0)
+
+#define UB913_REG_MODE_SEL                     0x05
+#define UB913_REG_MODE_SEL_MODE_OVERRIDE       BIT(5)
+#define UB913_REG_MODE_SEL_MODE_UP_TO_DATE     BIT(4)
+#define UB913_REG_MODE_SEL_MODE_MASK           GENMASK(3, 0)
+
+#define UB913_REG_CRC_ERRORS_LSB               0x0a
+#define UB913_REG_CRC_ERRORS_MSB               0x0b
+
+#define UB913_REG_GENERAL_STATUS               0x0c
+
+#define UB913_REG_GPIO_CFG(n)                  (0x0d + (n))
+#define UB913_REG_GPIO_CFG_ENABLE(n)           BIT(0 + (n) * 4)
+#define UB913_REG_GPIO_CFG_DIR_INPUT(n)                BIT(1 + (n) * 4)
+#define UB913_REG_GPIO_CFG_REMOTE_EN(n)                BIT(2 + (n) * 4)
+#define UB913_REG_GPIO_CFG_OUT_VAL(n)          BIT(3 + (n) * 4)
+#define UB913_REG_GPIO_CFG_MASK(n)             (0xf << ((n) * 4))
+
+#define UB913_REG_SCL_HIGH_TIME                        0x11
+#define UB913_REG_SCL_LOW_TIME                 0x12
+
+#define UB913_REG_PLL_OVR                      0x35
+
+struct ub913_data {
+       struct i2c_client       *client;
+       struct regmap           *regmap;
+       struct clk              *clkin;
+
+       struct gpio_chip        gpio_chip;
+
+       struct v4l2_subdev      sd;
+       struct media_pad        pads[2];
+
+       struct v4l2_async_notifier      notifier;
+
+       struct v4l2_subdev      *source_sd;
+       u16                     source_sd_pad;
+
+       u64                     enabled_source_streams;
+
+       struct clk_hw           *clkout_clk_hw;
+
+       struct ds90ub9xx_platform_data *plat_data;
+
+       u32                     pclk_polarity;
+};
+
+static inline struct ub913_data *sd_to_ub913(struct v4l2_subdev *sd)
+{
+       return container_of(sd, struct ub913_data, sd);
+}
+
+struct ub913_format_info {
+       u32 incode;
+       u32 outcode;
+};
+
+static const struct ub913_format_info ub913_formats[] = {
+       /* Only RAW10 with 8-bit payload is supported at the moment */
+       { .incode = MEDIA_BUS_FMT_YUYV8_2X8, .outcode = MEDIA_BUS_FMT_YUYV8_1X16 },
+       { .incode = MEDIA_BUS_FMT_UYVY8_2X8, .outcode = MEDIA_BUS_FMT_UYVY8_1X16 },
+       { .incode = MEDIA_BUS_FMT_VYUY8_2X8, .outcode = MEDIA_BUS_FMT_VYUY8_1X16 },
+       { .incode = MEDIA_BUS_FMT_YVYU8_2X8, .outcode = MEDIA_BUS_FMT_YVYU8_1X16 },
+};
+
+static const struct ub913_format_info *ub913_find_format(u32 incode)
+{
+       unsigned int i;
+
+       for (i = 0; i < ARRAY_SIZE(ub913_formats); i++) {
+               if (ub913_formats[i].incode == incode)
+                       return &ub913_formats[i];
+       }
+
+       return NULL;
+}
+
+static int ub913_read(const struct ub913_data *priv, u8 reg, u8 *val)
+{
+       unsigned int v;
+       int ret;
+
+       ret = regmap_read(priv->regmap, reg, &v);
+       if (ret < 0) {
+               dev_err(&priv->client->dev,
+                       "Cannot read register 0x%02x: %d!\n", reg, ret);
+               return ret;
+       }
+
+       *val = v;
+       return 0;
+}
+
+static int ub913_write(const struct ub913_data *priv, u8 reg, u8 val)
+{
+       int ret;
+
+       ret = regmap_write(priv->regmap, reg, val);
+       if (ret < 0)
+               dev_err(&priv->client->dev,
+                       "Cannot write register 0x%02x: %d!\n", reg, ret);
+
+       return ret;
+}
+
+/*
+ * GPIO chip
+ */
+static int ub913_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+       return GPIO_LINE_DIRECTION_OUT;
+}
+
+static int ub913_gpio_direction_out(struct gpio_chip *gc, unsigned int offset,
+                                   int value)
+{
+       struct ub913_data *priv = gpiochip_get_data(gc);
+       unsigned int reg_idx = offset / 2;
+       unsigned int field_idx = offset % 2;
+
+       return regmap_update_bits(priv->regmap, UB913_REG_GPIO_CFG(reg_idx),
+                                 UB913_REG_GPIO_CFG_MASK(field_idx),
+                                 UB913_REG_GPIO_CFG_ENABLE(field_idx) |
+                                         (value ? UB913_REG_GPIO_CFG_OUT_VAL(field_idx) :
+                                                  0));
+}
+
+static void ub913_gpio_set(struct gpio_chip *gc, unsigned int offset, int value)
+{
+       ub913_gpio_direction_out(gc, offset, value);
+}
+
+static int ub913_gpio_of_xlate(struct gpio_chip *gc,
+                              const struct of_phandle_args *gpiospec,
+                              u32 *flags)
+{
+       if (flags)
+               *flags = gpiospec->args[1];
+
+       return gpiospec->args[0];
+}
+
+static int ub913_gpiochip_probe(struct ub913_data *priv)
+{
+       struct device *dev = &priv->client->dev;
+       struct gpio_chip *gc = &priv->gpio_chip;
+       int ret;
+
+       /* Initialize GPIOs 0 and 1 to local control, tri-state */
+       ub913_write(priv, UB913_REG_GPIO_CFG(0), 0);
+
+       gc->label = dev_name(dev);
+       gc->parent = dev;
+       gc->owner = THIS_MODULE;
+       gc->base = -1;
+       gc->can_sleep = true;
+       gc->ngpio = UB913_NUM_GPIOS;
+       gc->get_direction = ub913_gpio_get_direction;
+       gc->direction_output = ub913_gpio_direction_out;
+       gc->set = ub913_gpio_set;
+       gc->of_xlate = ub913_gpio_of_xlate;
+       gc->of_gpio_n_cells = 2;
+
+       ret = gpiochip_add_data(gc, priv);
+       if (ret) {
+               dev_err(dev, "Failed to add GPIOs: %d\n", ret);
+               return ret;
+       }
+
+       return 0;
+}
+
+static void ub913_gpiochip_remove(struct ub913_data *priv)
+{
+       gpiochip_remove(&priv->gpio_chip);
+}
+
+static const struct regmap_config ub913_regmap_config = {
+       .name = "ds90ub913",
+       .reg_bits = 8,
+       .val_bits = 8,
+       .reg_format_endian = REGMAP_ENDIAN_DEFAULT,
+       .val_format_endian = REGMAP_ENDIAN_DEFAULT,
+};
+
+/*
+ * V4L2
+ */
+
+static int ub913_enable_streams(struct v4l2_subdev *sd,
+                               struct v4l2_subdev_state *state, u32 pad,
+                               u64 streams_mask)
+{
+       struct ub913_data *priv = sd_to_ub913(sd);
+       u64 sink_streams;
+       int ret;
+
+       sink_streams = v4l2_subdev_state_xlate_streams(state, UB913_PAD_SOURCE,
+                                                      UB913_PAD_SINK,
+                                                      &streams_mask);
+
+       ret = v4l2_subdev_enable_streams(priv->source_sd, priv->source_sd_pad,
+                                        sink_streams);
+       if (ret)
+               return ret;
+
+       priv->enabled_source_streams |= streams_mask;
+
+       return 0;
+}
+
+static int ub913_disable_streams(struct v4l2_subdev *sd,
+                                struct v4l2_subdev_state *state, u32 pad,
+                                u64 streams_mask)
+{
+       struct ub913_data *priv = sd_to_ub913(sd);
+       u64 sink_streams;
+       int ret;
+
+       sink_streams = v4l2_subdev_state_xlate_streams(state, UB913_PAD_SOURCE,
+                                                      UB913_PAD_SINK,
+                                                      &streams_mask);
+
+       ret = v4l2_subdev_disable_streams(priv->source_sd, priv->source_sd_pad,
+                                         sink_streams);
+       if (ret)
+               return ret;
+
+       priv->enabled_source_streams &= ~streams_mask;
+
+       return 0;
+}
+
+static int _ub913_set_routing(struct v4l2_subdev *sd,
+                             struct v4l2_subdev_state *state,
+                             struct v4l2_subdev_krouting *routing)
+{
+       static const struct v4l2_mbus_framefmt in_format = {
+               .width = 640,
+               .height = 480,
+               .code = MEDIA_BUS_FMT_UYVY8_2X8,
+               .field = V4L2_FIELD_NONE,
+               .colorspace = V4L2_COLORSPACE_SRGB,
+               .ycbcr_enc = V4L2_YCBCR_ENC_601,
+               .quantization = V4L2_QUANTIZATION_LIM_RANGE,
+               .xfer_func = V4L2_XFER_FUNC_SRGB,
+       };
+       static const struct v4l2_mbus_framefmt out_format = {
+               .width = 640,
+               .height = 480,
+               .code = MEDIA_BUS_FMT_UYVY8_1X16,
+               .field = V4L2_FIELD_NONE,
+               .colorspace = V4L2_COLORSPACE_SRGB,
+               .ycbcr_enc = V4L2_YCBCR_ENC_601,
+               .quantization = V4L2_QUANTIZATION_LIM_RANGE,
+               .xfer_func = V4L2_XFER_FUNC_SRGB,
+       };
+       struct v4l2_subdev_stream_configs *stream_configs;
+       unsigned int i;
+       int ret;
+
+       /*
+        * Note: we can only support up to V4L2_FRAME_DESC_ENTRY_MAX, until
+        * frame desc is made dynamically allocated.
+        */
+
+       if (routing->num_routes > V4L2_FRAME_DESC_ENTRY_MAX)
+               return -EINVAL;
+
+       ret = v4l2_subdev_routing_validate(sd, routing,
+                                          V4L2_SUBDEV_ROUTING_ONLY_1_TO_1);
+       if (ret)
+               return ret;
+
+       ret = v4l2_subdev_set_routing(sd, state, routing);
+       if (ret)
+               return ret;
+
+       stream_configs = &state->stream_configs;
+
+       for (i = 0; i < stream_configs->num_configs; i++) {
+               if (stream_configs->configs[i].pad == UB913_PAD_SINK)
+                       stream_configs->configs[i].fmt = in_format;
+               else
+                       stream_configs->configs[i].fmt = out_format;
+       }
+
+       return 0;
+}
+
+static int ub913_set_routing(struct v4l2_subdev *sd,
+                            struct v4l2_subdev_state *state,
+                            enum v4l2_subdev_format_whence which,
+                            struct v4l2_subdev_krouting *routing)
+{
+       struct ub913_data *priv = sd_to_ub913(sd);
+
+       if (which == V4L2_SUBDEV_FORMAT_ACTIVE && priv->enabled_source_streams)
+               return -EBUSY;
+
+       return _ub913_set_routing(sd, state, routing);
+}
+
+static int ub913_get_frame_desc(struct v4l2_subdev *sd, unsigned int pad,
+                               struct v4l2_mbus_frame_desc *fd)
+{
+       struct ub913_data *priv = sd_to_ub913(sd);
+       const struct v4l2_subdev_krouting *routing;
+       struct v4l2_mbus_frame_desc source_fd;
+       struct v4l2_subdev_route *route;
+       struct v4l2_subdev_state *state;
+       int ret;
+
+       if (pad != UB913_PAD_SOURCE)
+               return -EINVAL;
+
+       ret = v4l2_subdev_call(priv->source_sd, pad, get_frame_desc,
+                              priv->source_sd_pad, &source_fd);
+       if (ret)
+               return ret;
+
+       memset(fd, 0, sizeof(*fd));
+
+       fd->type = V4L2_MBUS_FRAME_DESC_TYPE_PARALLEL;
+
+       state = v4l2_subdev_lock_and_get_active_state(sd);
+
+       routing = &state->routing;
+
+       for_each_active_route(routing, route) {
+               unsigned int i;
+
+               if (route->source_pad != pad)
+                       continue;
+
+               for (i = 0; i < source_fd.num_entries; i++) {
+                       if (source_fd.entry[i].stream == route->sink_stream)
+                               break;
+               }
+
+               if (i == source_fd.num_entries) {
+                       dev_err(&priv->client->dev,
+                               "Failed to find stream from source frame desc\n");
+                       ret = -EPIPE;
+                       goto out_unlock;
+               }
+
+               fd->entry[fd->num_entries].stream = route->source_stream;
+               fd->entry[fd->num_entries].flags = source_fd.entry[i].flags;
+               fd->entry[fd->num_entries].length = source_fd.entry[i].length;
+               fd->entry[fd->num_entries].pixelcode =
+                       source_fd.entry[i].pixelcode;
+
+               fd->num_entries++;
+       }
+
+out_unlock:
+       v4l2_subdev_unlock_state(state);
+
+       return ret;
+}
+
+static int ub913_set_fmt(struct v4l2_subdev *sd,
+                        struct v4l2_subdev_state *state,
+                        struct v4l2_subdev_format *format)
+{
+       struct ub913_data *priv = sd_to_ub913(sd);
+       struct v4l2_mbus_framefmt *fmt;
+       const struct ub913_format_info *finfo;
+
+       if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE &&
+           priv->enabled_source_streams)
+               return -EBUSY;
+
+       /* Source format is fully defined by the sink format, so not settable */
+       if (format->pad == UB913_PAD_SOURCE)
+               return v4l2_subdev_get_fmt(sd, state, format);
+
+       finfo = ub913_find_format(format->format.code);
+       if (!finfo) {
+               finfo = &ub913_formats[0];
+               format->format.code = finfo->incode;
+       }
+
+       /* Set sink format */
+       fmt = v4l2_subdev_state_get_stream_format(state, format->pad,
+                                                 format->stream);
+       if (!fmt)
+               return -EINVAL;
+
+       *fmt = format->format;
+
+       /* Propagate to source format, and adjust the mbus code */
+       fmt = v4l2_subdev_state_get_opposite_stream_format(state, format->pad,
+                                                          format->stream);
+       if (!fmt)
+               return -EINVAL;
+
+       format->format.code = finfo->outcode;
+
+       *fmt = format->format;
+
+       return 0;
+}
+
+static int ub913_init_cfg(struct v4l2_subdev *sd,
+                         struct v4l2_subdev_state *state)
+{
+       struct v4l2_subdev_route routes[] = {
+               {
+                       .sink_pad = UB913_PAD_SINK,
+                       .sink_stream = 0,
+                       .source_pad = UB913_PAD_SOURCE,
+                       .source_stream = 0,
+                       .flags = V4L2_SUBDEV_ROUTE_FL_ACTIVE,
+               },
+       };
+
+       struct v4l2_subdev_krouting routing = {
+               .num_routes = ARRAY_SIZE(routes),
+               .routes = routes,
+       };
+
+       return _ub913_set_routing(sd, state, &routing);
+}
+
+static int ub913_log_status(struct v4l2_subdev *sd)
+{
+       struct ub913_data *priv = sd_to_ub913(sd);
+       struct device *dev = &priv->client->dev;
+       u8 v, v1, v2;
+
+       ub913_read(priv, UB913_REG_MODE_SEL, &v);
+       dev_info(dev, "MODE_SEL %#02x\n", v);
+
+       ub913_read(priv, UB913_REG_CRC_ERRORS_LSB, &v1);
+       ub913_read(priv, UB913_REG_CRC_ERRORS_MSB, &v2);
+       dev_info(dev, "CRC errors %u\n", v1 | (v2 << 8));
+
+       /* clear CRC errors */
+       ub913_read(priv, UB913_REG_GENERAL_CFG, &v);
+       ub913_write(priv, UB913_REG_GENERAL_CFG,
+                   v | UB913_REG_GENERAL_CFG_CRC_ERR_RESET);
+       ub913_write(priv, UB913_REG_GENERAL_CFG, v);
+
+       ub913_read(priv, UB913_REG_GENERAL_STATUS, &v);
+       dev_info(dev, "GENERAL_STATUS %#02x\n", v);
+
+       ub913_read(priv, UB913_REG_PLL_OVR, &v);
+       dev_info(dev, "PLL_OVR %#02x\n", v);
+
+       return 0;
+}
+
+static const struct v4l2_subdev_core_ops ub913_subdev_core_ops = {
+       .log_status = ub913_log_status,
+};
+
+static const struct v4l2_subdev_pad_ops ub913_pad_ops = {
+       .enable_streams = ub913_enable_streams,
+       .disable_streams = ub913_disable_streams,
+       .set_routing = ub913_set_routing,
+       .get_frame_desc = ub913_get_frame_desc,
+       .get_fmt = v4l2_subdev_get_fmt,
+       .set_fmt = ub913_set_fmt,
+       .init_cfg = ub913_init_cfg,
+};
+
+static const struct v4l2_subdev_ops ub913_subdev_ops = {
+       .core = &ub913_subdev_core_ops,
+       .pad = &ub913_pad_ops,
+};
+
+static const struct media_entity_operations ub913_entity_ops = {
+       .link_validate = v4l2_subdev_link_validate,
+};
+
+static int ub913_notify_bound(struct v4l2_async_notifier *notifier,
+                             struct v4l2_subdev *source_subdev,
+                             struct v4l2_async_subdev *asd)
+{
+       struct ub913_data *priv = sd_to_ub913(notifier->sd);
+       struct device *dev = &priv->client->dev;
+       int ret;
+
+       ret = media_entity_get_fwnode_pad(&source_subdev->entity,
+                                         source_subdev->fwnode,
+                                         MEDIA_PAD_FL_SOURCE);
+       if (ret < 0) {
+               dev_err(dev, "Failed to find pad for %s\n",
+                       source_subdev->name);
+               return ret;
+       }
+
+       priv->source_sd = source_subdev;
+       priv->source_sd_pad = ret;
+
+       ret = media_create_pad_link(&source_subdev->entity, priv->source_sd_pad,
+                                   &priv->sd.entity, UB913_PAD_SINK,
+                                   MEDIA_LNK_FL_ENABLED |
+                                           MEDIA_LNK_FL_IMMUTABLE);
+       if (ret) {
+               dev_err(dev, "Unable to link %s:%u -> %s:0\n",
+                       source_subdev->name, priv->source_sd_pad,
+                       priv->sd.name);
+               return ret;
+       }
+
+       return 0;
+}
+
+static const struct v4l2_async_notifier_operations ub913_notify_ops = {
+       .bound = ub913_notify_bound,
+};
+
+static int ub913_v4l2_notifier_register(struct ub913_data *priv)
+{
+       struct device *dev = &priv->client->dev;
+       struct v4l2_async_subdev *asd;
+       struct fwnode_handle *ep_fwnode;
+       int ret;
+
+       ep_fwnode = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev),
+                                                   UB913_PAD_SINK, 0, 0);
+       if (!ep_fwnode) {
+               dev_err(dev, "No graph endpoint\n");
+               return -ENODEV;
+       }
+
+       v4l2_async_nf_init(&priv->notifier);
+
+       asd = v4l2_async_nf_add_fwnode_remote(&priv->notifier, ep_fwnode,
+                                             struct v4l2_async_subdev);
+
+       fwnode_handle_put(ep_fwnode);
+
+       if (IS_ERR(asd)) {
+               dev_err(dev, "Failed to add subdev: %ld", PTR_ERR(asd));
+               v4l2_async_nf_cleanup(&priv->notifier);
+               return PTR_ERR(asd);
+       }
+
+       priv->notifier.ops = &ub913_notify_ops;
+
+       ret = v4l2_async_subdev_nf_register(&priv->sd, &priv->notifier);
+       if (ret) {
+               dev_err(dev, "Failed to register subdev_notifier");
+               v4l2_async_nf_cleanup(&priv->notifier);
+               return ret;
+       }
+
+       return 0;
+}
+
+static void ub913_v4l2_nf_unregister(struct ub913_data *priv)
+{
+       v4l2_async_nf_unregister(&priv->notifier);
+       v4l2_async_nf_cleanup(&priv->notifier);
+}
+
+static int ub913_register_clkout(struct ub913_data *priv)
+{
+       struct device *dev = &priv->client->dev;
+       const char *name;
+       int ret;
+
+       name = kasprintf(GFP_KERNEL, "ds90ub913.%s.clk_out", dev_name(dev));
+       if (!name)
+               return -ENOMEM;
+
+       priv->clkout_clk_hw = devm_clk_hw_register_fixed_factor(dev, name,
+               __clk_get_name(priv->clkin), 0, 1, 2);
+
+       kfree(name);
+
+       if (IS_ERR(priv->clkout_clk_hw))
+               return dev_err_probe(dev, PTR_ERR(priv->clkout_clk_hw),
+                                    "Cannot register clkout hw\n");
+
+       ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
+                                         priv->clkout_clk_hw);
+       if (ret)
+               return dev_err_probe(dev, ret,
+                                    "Cannot add OF clock provider\n");
+
+       return 0;
+}
+
+static int ub913_i2c_master_init(struct ub913_data *priv)
+{
+       /* i2c fast mode */
+       u32 scl_high = 600 + 300; /* high period + rise time, ns */
+       u32 scl_low = 1300 + 300; /* low period + fall time, ns */
+       unsigned long ref;
+       int ret;
+
+       ref = clk_get_rate(priv->clkin) / 2;
+
+       scl_high = div64_u64((u64)scl_high * ref, 1000000000);
+       scl_low = div64_u64((u64)scl_low * ref, 1000000000);
+
+       ret = ub913_write(priv, UB913_REG_SCL_HIGH_TIME, scl_high);
+       if (ret)
+               return ret;
+
+       ret = ub913_write(priv, UB913_REG_SCL_LOW_TIME, scl_low);
+       if (ret)
+               return ret;
+
+       return 0;
+}
+
+static int ub913_add_i2c_adapter(struct ub913_data *priv)
+{
+       struct device *dev = &priv->client->dev;
+       struct fwnode_handle *i2c_handle;
+       int ret;
+
+       i2c_handle = device_get_named_child_node(dev, "i2c");
+       if (!i2c_handle)
+               return 0;
+
+       ret = i2c_atr_add_adapter(priv->plat_data->atr, priv->plat_data->port,
+                                 dev, i2c_handle);
+
+       fwnode_handle_put(i2c_handle);
+
+       if (ret)
+               return ret;
+
+       return 0;
+}
+
+static int ub913_parse_dt(struct ub913_data *priv)
+{
+       struct device *dev = &priv->client->dev;
+       struct fwnode_handle *ep_fwnode;
+       int ret;
+
+       ep_fwnode = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev),
+                                                   UB913_PAD_SINK, 0, 0);
+       if (!ep_fwnode) {
+               dev_err_probe(dev, -ENOENT, "No sink endpoint\n");
+               return -ENOENT;
+       }
+
+       ret = fwnode_property_read_u32(ep_fwnode, "pclk-sample",
+                                      &priv->pclk_polarity);
+
+       fwnode_handle_put(ep_fwnode);
+
+       if (ret) {
+               dev_err_probe(dev, ret, "failed to parse 'pclk-sample'\n");
+               return ret;
+       }
+
+       return 0;
+}
+
+static int ub913_hw_init(struct ub913_data *priv)
+{
+       struct device *dev = &priv->client->dev;
+       bool mode_override;
+       u8 mode;
+       int ret;
+       u8 v;
+
+       ret = ub913_read(priv, UB913_REG_MODE_SEL, &v);
+       if (ret)
+               return ret;
+
+       if (!(v & UB913_REG_MODE_SEL_MODE_UP_TO_DATE))
+               return dev_err_probe(dev, -ENODEV,
+                                    "Mode value not stabilized\n");
+
+       mode_override = v & UB913_REG_MODE_SEL_MODE_OVERRIDE;
+       mode = v & UB913_REG_MODE_SEL_MODE_MASK;
+
+       dev_dbg(dev, "mode from %s: %#x\n",
+               mode_override ? "reg" : "deserializer", mode);
+
+       ret = ub913_i2c_master_init(priv);
+       if (ret)
+               return dev_err_probe(dev, ret, "i2c master init failed\n");
+
+       ub913_read(priv, UB913_REG_GENERAL_CFG, &v);
+       v &= ~UB913_REG_GENERAL_CFG_PCLK_RISING;
+       v |= priv->pclk_polarity ? UB913_REG_GENERAL_CFG_PCLK_RISING : 0;
+       ub913_write(priv, UB913_REG_GENERAL_CFG, v);
+
+       return 0;
+}
+
+static int ub913_subdev_init(struct ub913_data *priv)
+{
+       struct device *dev = &priv->client->dev;
+       int ret;
+
+       v4l2_i2c_subdev_init(&priv->sd, priv->client, &ub913_subdev_ops);
+       priv->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE | V4L2_SUBDEV_FL_STREAMS;
+       priv->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
+       priv->sd.entity.ops = &ub913_entity_ops;
+
+       priv->pads[0].flags = MEDIA_PAD_FL_SINK;
+       priv->pads[1].flags = MEDIA_PAD_FL_SOURCE;
+
+       ret = media_entity_pads_init(&priv->sd.entity, 2, priv->pads);
+       if (ret)
+               return dev_err_probe(dev, ret, "Failed to init pads\n");
+
+       priv->sd.fwnode = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev),
+                                                         UB913_PAD_SOURCE, 0,
+                                                         0);
+
+       if (!priv->sd.fwnode) {
+               ret = -ENODEV;
+               dev_err_probe(dev, ret, "Missing TX endpoint\n");
+               goto err_entity_cleanup;
+       }
+
+       ret = v4l2_subdev_init_finalize(&priv->sd);
+       if (ret)
+               goto err_fwnode_put;
+
+       ret = ub913_v4l2_notifier_register(priv);
+       if (ret) {
+               dev_err_probe(dev, ret,
+                             "v4l2 subdev notifier register failed\n");
+               goto err_subdev_cleanup;
+       }
+
+       ret = v4l2_async_register_subdev(&priv->sd);
+       if (ret) {
+               dev_err_probe(dev, ret, "v4l2_async_register_subdev error\n");
+               goto err_unreg_notif;
+       }
+
+       return 0;
+
+err_unreg_notif:
+       ub913_v4l2_nf_unregister(priv);
+err_subdev_cleanup:
+       v4l2_subdev_cleanup(&priv->sd);
+err_fwnode_put:
+       fwnode_handle_put(priv->sd.fwnode);
+err_entity_cleanup:
+       media_entity_cleanup(&priv->sd.entity);
+
+       return ret;
+}
+
+static void ub913_subdev_uninit(struct ub913_data *priv)
+{
+       v4l2_async_unregister_subdev(&priv->sd);
+       ub913_v4l2_nf_unregister(priv);
+       v4l2_subdev_cleanup(&priv->sd);
+       fwnode_handle_put(priv->sd.fwnode);
+       media_entity_cleanup(&priv->sd.entity);
+}
+
+static int ub913_probe(struct i2c_client *client)
+{
+       struct device *dev = &client->dev;
+       struct ub913_data *priv;
+       int ret;
+
+       priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       priv->client = client;
+
+       priv->plat_data = dev_get_platdata(&client->dev);
+       if (!priv->plat_data)
+               return dev_err_probe(dev, -ENODEV, "Platform data missing\n");
+
+       priv->regmap = devm_regmap_init_i2c(client, &ub913_regmap_config);
+       if (IS_ERR(priv->regmap))
+               return dev_err_probe(dev, PTR_ERR(priv->regmap),
+                                    "Failed to init regmap\n");
+
+       /*
+        * ub913 can also work without ext clock, but that is not supported by
+        * the driver yet.
+        */
+       priv->clkin = devm_clk_get(dev, "clkin");
+       if (IS_ERR(priv->clkin))
+               return dev_err_probe(dev, PTR_ERR(priv->clkin),
+                                    "Cannot get CLKIN\n");
+
+       ret = ub913_parse_dt(priv);
+       if (ret)
+               return ret;
+
+       ret = ub913_hw_init(priv);
+       if (ret)
+               return ret;
+
+       ret = ub913_gpiochip_probe(priv);
+       if (ret)
+               return dev_err_probe(dev, ret, "Failed to init gpiochip\n");
+
+       ret = ub913_register_clkout(priv);
+       if (ret) {
+               dev_err_probe(dev, ret, "Failed to register clkout\n");
+               goto err_gpiochip_remove;
+       }
+
+       ret = ub913_subdev_init(priv);
+       if (ret)
+               goto err_gpiochip_remove;
+
+       ret = ub913_add_i2c_adapter(priv);
+       if (ret) {
+               dev_err_probe(dev, ret, "failed to add remote i2c adapter\n");
+               goto err_subdev_uninit;
+       }
+
+       return 0;
+
+err_subdev_uninit:
+       ub913_subdev_uninit(priv);
+err_gpiochip_remove:
+       ub913_gpiochip_remove(priv);
+
+       return ret;
+}
+
+static void ub913_remove(struct i2c_client *client)
+{
+       struct v4l2_subdev *sd = i2c_get_clientdata(client);
+       struct ub913_data *priv = sd_to_ub913(sd);
+
+       i2c_atr_del_adapter(priv->plat_data->atr, priv->plat_data->port);
+
+       ub913_subdev_uninit(priv);
+
+       ub913_gpiochip_remove(priv);
+}
+
+static const struct i2c_device_id ub913_id[] = { { "ds90ub913a-q1", 0 }, {} };
+MODULE_DEVICE_TABLE(i2c, ub913_id);
+
+static const struct of_device_id ub913_dt_ids[] = {
+       { .compatible = "ti,ds90ub913a-q1" },
+       {}
+};
+MODULE_DEVICE_TABLE(of, ub913_dt_ids);
+
+static struct i2c_driver ds90ub913_driver = {
+       .probe_new      = ub913_probe,
+       .remove         = ub913_remove,
+       .id_table       = ub913_id,
+       .driver = {
+               .name   = "ds90ub913a",
+               .of_match_table = ub913_dt_ids,
+       },
+};
+module_i2c_driver(ds90ub913_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Texas Instruments DS90UB913 FPD-Link III Serializer Driver");
+MODULE_AUTHOR("Luca Ceresoli <luca@lucaceresoli.net>");
+MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>");
+MODULE_IMPORT_NS(I2C_ATR);