Hi Tomi, Thank you for the patch. On Thu, Jan 05, 2023 at 04:03:06PM +0200, Tomi Valkeinen wrote: > Add driver for TI DS90UB913 FPD-Link III Serializer. > > Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx> > --- > drivers/media/i2c/Kconfig | 13 + > drivers/media/i2c/Makefile | 2 +- > drivers/media/i2c/ds90ub913.c | 871 ++++++++++++++++++++++++++++++++++ > 3 files changed, 885 insertions(+), 1 deletion(-) > create mode 100644 drivers/media/i2c/ds90ub913.c > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig > index f95a54454e17..eb312d6e9cf6 100644 > --- a/drivers/media/i2c/Kconfig > +++ b/drivers/media/i2c/Kconfig > @@ -1601,6 +1601,19 @@ endmenu > > menu "Video serializers and deserializers" > > +config VIDEO_DS90UB913 > + tristate "TI DS90UB913 Serializer" > + depends on OF && I2C && VIDEO_DEV > + select MEDIA_CONTROLLER > + select VIDEO_V4L2_SUBDEV_API > + select V4L2_FWNODE > + select REGMAP_I2C > + select OF_GPIO > + select I2C_ATR Maybe alphabetical order ? > + help > + Device driver for the Texas Instruments DS90UB913 > + FPD-Link III Serializer. > + > config VIDEO_DS90UB960 > tristate "TI DS90UB960 Deserializer" > depends on OF && I2C && VIDEO_DEV > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile > index 2735b00437bb..c4875ec8c3b9 100644 > --- a/drivers/media/i2c/Makefile > +++ b/drivers/media/i2c/Makefile > @@ -142,5 +142,5 @@ obj-$(CONFIG_VIDEO_VPX3220) += vpx3220.o > obj-$(CONFIG_VIDEO_VS6624) += vs6624.o > obj-$(CONFIG_VIDEO_WM8739) += wm8739.o > obj-$(CONFIG_VIDEO_WM8775) += wm8775.o > +obj-$(CONFIG_VIDEO_DS90UB913) += ds90ub913.o > obj-$(CONFIG_VIDEO_DS90UB960) += ds90ub960.o > - Don't add the blank line in 6/8 if you remove it here :-) > diff --git a/drivers/media/i2c/ds90ub913.c b/drivers/media/i2c/ds90ub913.c > new file mode 100644 > index 000000000000..0a60afb09cd3 > --- /dev/null > +++ b/drivers/media/i2c/ds90ub913.c > @@ -0,0 +1,871 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Driver for the Texas Instruments DS90UB913 video serializer > + * > + * Based on a driver from Luca Ceresoli <luca@xxxxxxxxxxxxxxxx> > + * > + * Copyright (c) 2019 Luca Ceresoli <luca@xxxxxxxxxxxxxxxx> > + * Copyright (c) 2022 Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx> Happy new year :-) > + */ > + > +#include <linux/clk-provider.h> > +#include <linux/clk.h> > +#include <linux/delay.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/of.h> > +#include <linux/of_graph.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_UP_TO_DATE BIT(4) > +#define UB913_REG_MODE_SEL_MODE_OVERRIDE BIT(5) > + > +#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; > + char gpio_chip_name[64]; > + > + struct v4l2_subdev sd; > + struct media_pad pads[2]; > + > + struct v4l2_async_notifier notifier; > + > + struct v4l2_subdev *source_sd; > + > + u64 enabled_source_streams; > + > + struct device_node *tx_ep_np; > + > + 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); > +} > + > +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; > + unsigned int field_idx; > + int ret; > + > + reg_idx = offset / 2; > + field_idx = offset % 2; You could initialize those two variables when declaring them, up to you. > + > + ret = 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)); > + > + return ret; No need for a ret variable, you can write 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); > + > + scnprintf(priv->gpio_chip_name, sizeof(priv->gpio_chip_name), "%s", > + dev_name(dev)); I think you can use strscpy(). > + > + gc->label = priv->gpio_chip_name; > + gc->parent = dev; > + gc->owner = THIS_MODULE; > + gc->base = -1; > + gc->can_sleep = 1; can_sleep is a bool, 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_node = priv->client->dev.of_node; > + 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); > + struct media_pad *remote_pad; > + u64 sink_streams; > + int ret; > + > + if (streams_mask & priv->enabled_source_streams) > + return -EALREADY; I may recall incorrectly, but doesn't the subdev core already prevent this from happening ? > + > + sink_streams = v4l2_subdev_state_xlate_streams( > + state, UB913_PAD_SOURCE, UB913_PAD_SINK, &streams_mask); > + > + remote_pad = media_pad_remote_pad_first(&priv->pads[UB913_PAD_SINK]); As the remote pad should never change, how about caching it in the ub913_data structrue at probe time and using it here and in other functions below ? You already cache the source subdev. > + > + ret = v4l2_subdev_enable_streams(priv->source_sd, remote_pad->index, > + 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); > + struct media_pad *remote_pad; > + int ret; > + u64 sink_streams; Swap ret and sink_streams. > + > + if ((streams_mask & priv->enabled_source_streams) != streams_mask) > + return -EALREADY; > + > + sink_streams = v4l2_subdev_state_xlate_streams( > + state, UB913_PAD_SOURCE, UB913_PAD_SINK, &streams_mask); > + > + remote_pad = media_pad_remote_pad_first(&priv->pads[UB913_PAD_SINK]); > + > + ret = v4l2_subdev_disable_streams(priv->source_sd, remote_pad->index, > + 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 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, > + }; > + 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_with_fmt(sd, state, routing, &format); > + if (ret) > + return ret; > + > + 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_source_frame_desc(struct ub913_data *priv, > + struct v4l2_mbus_frame_desc *desc) > +{ > + struct media_pad *pad; > + int ret; > + > + pad = media_pad_remote_pad_first(&priv->pads[UB913_PAD_SINK]); > + if (!pad) > + return -EPIPE; > + > + ret = v4l2_subdev_call(priv->source_sd, pad, get_frame_desc, pad->index, > + desc); > + if (ret) > + return ret; > + > + return 0; > +} > + > +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 = ub913_get_source_frame_desc(priv, &source_fd); > + if (ret) > + return ret; > + > + state = v4l2_subdev_lock_and_get_active_state(sd); > + > + routing = &state->routing; > + > + memset(fd, 0, sizeof(*fd)); > + > + fd->type = V4L2_MBUS_FRAME_DESC_TYPE_PARALLEL; These two lines can be moved up, before locking the state. > + > + for_each_active_route(routing, route) { > + unsigned int i; > + > + if (route->source_pad != pad) > + continue; > + > + for (i = 0; i < source_fd.num_entries; ++i) Curly braces. > + 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; > + } > + > + 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++; Looks like we'll need helpers to simplify implementation of .get_frame_desc(). Not a candidate for this series. > + } > + > +out: > + 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; > + > + if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE && > + priv->enabled_source_streams) > + return -EBUSY; > + > + /* No transcoding, source and sink formats must match. */ > + if (format->pad == UB913_PAD_SOURCE) > + return v4l2_subdev_get_fmt(sd, state, format); > + > + /* 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 */ > + fmt = v4l2_subdev_state_get_opposite_stream_format(state, format->pad, > + format->stream); > + if (!fmt) > + return -EINVAL; > + > + *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 %#x\n", v); %#02x ? Same below. > + > + ub913_read(priv, UB913_REG_CRC_ERRORS_LSB, &v1); > + ub913_read(priv, UB913_REG_CRC_ERRORS_MSB, &v2); Looks racy, but if it's for debugging only, I suppose it's fine. > + dev_info(dev, "CRC errors %u\n", v1 | (v2 << 8)); > + > + ub913_read(priv, UB913_REG_GENERAL_STATUS, &v); > + dev_info(dev, "GENERAL_STATUS %#x\n", v); > + > + ub913_read(priv, UB913_REG_PLL_OVR, &v); > + dev_info(dev, "PLL_OVR %#x\n", v); > + > + /* 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); Line wrap. > + ub913_write(priv, UB913_REG_GENERAL_CFG, v); Move this just after reading the number of CRC errors to avoid dropping some errors. > + > + 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; > + unsigned int src_pad; > + 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; > + src_pad = ret; > + > + ret = media_create_pad_link(&source_subdev->entity, src_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, src_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 device_node *ep_node; > + int ret; > + > + ep_node = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0); > + if (!ep_node) { > + dev_err(dev, "No graph endpoint\n"); > + return -ENODEV; > + } > + > + v4l2_async_nf_init(&priv->notifier); > + > + asd = v4l2_async_nf_add_fwnode_remote(&priv->notifier, > + of_fwnode_handle(ep_node), > + struct v4l2_async_subdev); > + > + of_node_put(ep_node); > + > + 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, > + i2c_handle); > + > + fwnode_handle_put(i2c_handle); > + > + if (ret) > + return ret; > + > + return 0; > +} > + > +static int ub913_parse_dt(struct ub913_data *priv) > +{ > + struct device_node *np = priv->client->dev.of_node; > + struct device *dev = &priv->client->dev; > + int ret; > + struct device_node *ep_np; Swap ret and ep_np. > + > + if (!np) { > + dev_err(dev, "OF: no device tree node!\n"); > + return -ENOENT; > + } Can this happen ? > + > + ep_np = of_graph_get_endpoint_by_regs(np, 0, 0); > + if (!ep_np) { > + dev_err(dev, "OF: no endpoint\n"); > + return -ENOENT; > + } > + > + ret = of_property_read_u32(ep_np, "pclk-sample", &priv->pclk_polarity); > + > + of_node_put(ep_np); > + > + if (ret) { > + dev_err(dev, "OF: failed to parse pclk-sample: %d\n", ret); > + return ret; > + } > + > + return 0; > +} > + > +static int ub913_probe(struct i2c_client *client) > +{ > + struct device *dev = &client->dev; > + struct ub913_data *priv; > + int ret; > + u8 v; > + bool mode_override; > + u8 mode; > + > + 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) { > + dev_err(dev, "Platform data missing\n"); > + return -ENODEV; > + } > + > + priv->regmap = devm_regmap_init_i2c(client, &ub913_regmap_config); > + if (IS_ERR(priv->regmap)) { > + dev_err(dev, "Failed to init regmap\n"); > + return PTR_ERR(priv->regmap); > + } > + > + /* ub913 can also work without ext clock, but that is not supported */ Maybe "not supported by the driver yet." to make it clear it could be added ? > + priv->clkin = devm_clk_get(dev, "clkin"); > + if (IS_ERR(priv->clkin)) { > + ret = PTR_ERR(priv->clkin); > + if (ret != -EPROBE_DEFER) > + dev_err(dev, "Cannot get CLKIN (%d)", ret); Use dev_err_probe(). > + return ret; > + } > + > + ret = ub913_parse_dt(priv); > + if (ret) > + return ret; > + > + ret = ub913_read(priv, UB913_REG_MODE_SEL, &v); > + if (ret) > + return ret; > + > + if (!(v & UB913_REG_MODE_SEL_MODE_UP_TO_DATE)) { > + dev_err(dev, "Mode value not stabilized\n"); > + return -ENODEV; > + } > + > + mode_override = v & UB913_REG_MODE_SEL_MODE_OVERRIDE; > + mode = v & 0xf; A macro for the 0xf would be nice. > + > + dev_dbg(dev, "mode from %s: %#x\n", > + mode_override ? "reg" : "deserializer", mode); > + > + ret = ub913_i2c_master_init(priv); > + if (ret) { > + dev_err(dev, "i2c master init failed: %d\n", ret); > + return ret; > + } > + > + ret = ub913_gpiochip_probe(priv); > + if (ret) { > + dev_err(dev, "Failed to init gpiochip\n"); > + return ret; > + } > + > + ret = ub913_register_clkout(priv); > + if (ret) { > + dev_err(dev, "Failed to register clkout\n"); > + goto err_gpiochip_remove; > + } > + > + 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); We're completely missing power management, but I suppose that can be done later. Should this be grouped with the UB913_REG_MODE_SEL check above, and maybe moved to a hardware init function ? > + > + 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) { > + dev_err(dev, "Failed to init pads\n"); > + goto err_gpiochip_remove; > + } > + > + priv->tx_ep_np = of_graph_get_endpoint_by_regs(dev->of_node, 1, 0); > + if (priv->tx_ep_np) > + priv->sd.fwnode = of_fwnode_handle(priv->tx_ep_np); Can we meaningfully continue with tx_ep_np is NULL, or should that be an error ? > + > + ret = v4l2_subdev_init_finalize(&priv->sd); > + if (ret) > + goto err_entity_cleanup; > + > + ret = ub913_v4l2_notifier_register(priv); > + if (ret) { > + dev_err(dev, "v4l2 subdev notifier register failed: %d\n", ret); > + goto err_free_state; > + } > + > + ret = v4l2_async_register_subdev(&priv->sd); > + if (ret) { > + dev_err(dev, "v4l2_async_register_subdev error: %d\n", ret); > + goto err_unreg_notif; > + } > + > + ret = ub913_add_i2c_adapter(priv); > + if (ret) { > + dev_err(dev, "failed to add remote i2c adapter\n"); > + goto err_unreg_async_subdev; > + } > + > + return 0; > + > +err_unreg_async_subdev: > + v4l2_async_unregister_subdev(&priv->sd); > +err_unreg_notif: > + ub913_v4l2_nf_unregister(priv); > +err_free_state: I'd name this err_subdev_cleanup. > + v4l2_subdev_cleanup(&priv->sd); > +err_entity_cleanup: > + if (priv->tx_ep_np) > + of_node_put(priv->tx_ep_np); of_node_put() is a no-op when called with NULL, you can drop the check. Same below. > + > + media_entity_cleanup(&priv->sd.entity); > +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); > + > + v4l2_async_unregister_subdev(&priv->sd); > + > + ub913_v4l2_nf_unregister(priv); > + > + v4l2_subdev_cleanup(&priv->sd); > + > + if (priv->tx_ep_np) > + of_node_put(priv->tx_ep_np); > + > + media_entity_cleanup(&priv->sd.entity); > + > + ub913_gpiochip_remove(priv); > +} > + > +static const struct i2c_device_id ub913_id[] = { { "ds90ub913a-q1", 0 }, {} }; > +MODULE_DEVICE_TABLE(i2c, ub913_id); > + > +#ifdef CONFIG_OF The driver depends on CONFIG_OF so I would drop this, as well as the of_match_ptr(). > +static const struct of_device_id ub913_dt_ids[] = { > + { .compatible = "ti,ds90ub913a-q1", }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, ub913_dt_ids); > +#endif > + > +static struct i2c_driver ds90ub913_driver = { > + .probe_new = ub913_probe, > + .remove = ub913_remove, > + .id_table = ub913_id, > + .driver = { > + .name = "ds90ub913a", > + .owner = THIS_MODULE, > + .of_match_table = of_match_ptr(ub913_dt_ids), > + }, > +}; > + > +module_i2c_driver(ds90ub913_driver); > + > +MODULE_LICENSE("GPL"); > +MODULE_DESCRIPTION("Texas Instruments DS90UB913 serializer driver"); > +MODULE_AUTHOR("Luca Ceresoli <luca@xxxxxxxxxxxxxxxx>"); > +MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>"); > +MODULE_IMPORT_NS(I2C_ATR); -- Regards, Laurent Pinchart