[PATCH v1 2/3] media: imx: add a driver for i.MX8MQ mipi csi rx phy and controller
Martin Kepplinger
martin.kepplinger at puri.sm
Mon May 31 01:32:43 PDT 2021
Am Donnerstag, dem 27.05.2021 um 13:20 +0300 schrieb Dan Carpenter:
> On Thu, May 27, 2021 at 09:54:06AM +0200, Martin Kepplinger wrote:
> > +static void mipi_csi2_sw_reset(struct csi_state *state)
> > +{
> > + struct device *dev = state->dev;
> > + struct device_node *np = dev->of_node;
> > + struct device_node *node;
> > + phandle phandle;
> > + int ret;
> > +
> > + dev_dbg(dev, "%s: starting\n", __func__);
> > +
> > + ret = of_property_read_u32(np, "phy-reset", &phandle);
> > + if (ret) {
> > + dev_info(dev, "no csis-hw-reset property found:
> > %d\n", ret);
> > + return;
> > + }
> > +
> > + node = of_find_node_by_phandle(phandle);
> > + if (!node) {
> > + ret = PTR_ERR(node);
>
> Node is NULL, not an error pointer.
>
> > + dev_dbg(dev, "not find src node by phandle: %d\n",
> > ret);
>
> Probably change this to "error finding node by phandle\n".
> This should just return after printing the error.
> syscon_node_to_regmap()
> is not going to succeed with a NULL node.
>
> > + }
> > + state->hw_reset = syscon_node_to_regmap(node);
> > + if (IS_ERR(state->hw_reset)) {
> > + ret = PTR_ERR(state->hw_reset);
> > + dev_err(dev, "failed to get src regmap: %d\n",
> > ret);
>
> There is a new cool %pe which prints "failed to get src regmap: -
> ENODEV\n".
>
> dev_err(dev, "failed to get src regmap: %pe\n",
> state->hw_reset);
>
>
> > + }
> > + of_node_put(node);
> > + if (ret < 0)
> > + return;
> > +
> > + /* reset imx8mq mipi phy */
> > + regmap_update_bits(state->hw_reset, state->hw_reset_reg, 7,
> > 7);
> > + msleep(20);
> > +}
> > +
> > +static void mipi_csi2_system_enable(struct csi_state *state, int
> > on)
> > +{
> > + struct device *dev = state->dev;
> > + struct device_node *np = dev->of_node;
> > + struct device_node *node;
> > + phandle phandle;
> > + int ret;
> > +
> > + if (!on) {
> > + /* Disable Data lanes */
> > + mipi_csi2_write(state,
> > CSI2RX_CFG_DISABLE_DATA_LANES, 0xf);
> > + return;
> > + }
> > +
> > + ret = of_property_read_u32(np, "phy-gpr", &phandle);
> > + if (ret) {
> > + dev_info(dev, "no phy-gpr property found\n");
> > + return;
> > + }
> > +
> > + node = of_find_node_by_phandle(phandle);
> > + if (!node) {
> > + dev_dbg(dev, "not find gpr node by phandle\n");
> > + ret = PTR_ERR(node);
>
> Not an error pointer.
>
> > + }
> > + state->phy_gpr = syscon_node_to_regmap(node);
> > + if (IS_ERR(state->phy_gpr)) {
> > + dev_err(dev, "failed to get gpr regmap\n");
> > + ret = PTR_ERR(state->phy_gpr);
> > + }
> > + of_node_put(node);
> > + if (ret < 0)
> > + return;
> > +
> > + regmap_update_bits(state->phy_gpr,
> > + state->phy_gpr_reg,
> > + 0x3FFF,
> > + GPR_CSI2_1_RX_ENABLE |
> > + GPR_CSI2_1_VID_INTFC_ENB |
> > + GPR_CSI2_1_HSEL |
> > + GPR_CSI2_1_CONT_CLK_MODE |
> > + GPR_CSI2_1_S_PRG_RXHS_SETTLE(state-
> > >hs_settle));
> > +
> > + dev_dbg(dev, "%s: hs_settle: 0x%X\n", __func__, state-
> > >hs_settle);
> > +}
> > +
> > +static void mipi_csi2_set_params(struct csi_state *state)
> > +{
> > + int lanes = state->bus.num_data_lanes;
> > + u32 val = 0;
> > + int i;
> > +
> > + /* Lanes */
> > + mipi_csi2_write(state, CSI2RX_CFG_NUM_LANES, lanes - 1);
> > +
> > + for (i = 0; i < lanes; i++)
> > + val |= (1 << i);
> > +
> > + val = 0xF & ~val;
> > + mipi_csi2_write(state, CSI2RX_CFG_DISABLE_DATA_LANES, val);
> > +
> > + dev_dbg(state->dev, "imx8mq: CSI2RX_CFG_DISABLE_DATA_LANES:
> > 0x%X\n", val);
> > +
> > + /* Mask interrupt */
> > + // Don't let ULPS (ultra-low power status) interrupts flood
> > + mipi_csi2_write(state, CSI2RX_IRQ_MASK, 0x1ff);
> > +
> > + mipi_csi2_write(state, 0x180, 1);
> > + /* vid_vc */
> > + mipi_csi2_write(state, 0x184, 1);
> > + mipi_csi2_write(state, 0x188, state->send_level);
> > +}
> > +
> > +static int mipi_csi2_clk_enable(struct csi_state *state)
> > +{
> > + return
> > clk_bulk_prepare_enable(ARRAY_SIZE(mipi_csi2_clk_id), state->clks);
> > +}
> > +
> > +static void mipi_csi2_clk_disable(struct csi_state *state)
> > +{
> > + clk_bulk_disable_unprepare(ARRAY_SIZE(mipi_csi2_clk_id),
> > state->clks);
> > +}
> > +
> > +static int mipi_csi2_clk_get(struct csi_state *state)
> > +{
> > + unsigned int i;
> > + int ret;
> > +
> > + state->clks = devm_kcalloc(state->dev,
> > ARRAY_SIZE(mipi_csi2_clk_id),
> > + sizeof(*state->clks),
> > GFP_KERNEL);
> > +
> > + if (!state->clks)
> > + return -ENOMEM;
> > +
> > + for (i = 0; i < ARRAY_SIZE(mipi_csi2_clk_id); i++)
> > + state->clks[i].id = mipi_csi2_clk_id[i];
> > +
> > + ret = devm_clk_bulk_get(state->dev,
> > ARRAY_SIZE(mipi_csi2_clk_id),
> > + state->clks);
> > + return ret;
> > +}
> > +
> > +static void mipi_csi2_start_stream(struct csi_state *state)
> > +{
> > + mipi_csi2_sw_reset(state);
> > + mipi_csi2_set_params(state);
> > + mipi_csi2_system_enable(state, true);
> > +}
> > +
> > +static void mipi_csi2_stop_stream(struct csi_state *state)
> > +{
> > + mipi_csi2_system_enable(state, false);
> > +}
> > +
> > +/* ---------------------------------------------------------------
> > --------------
> > + * V4L2 subdev operations
> > + */
> > +
> > +static struct csi_state *mipi_sd_to_csi2_state(struct v4l2_subdev
> > *sdev)
> > +{
> > + return container_of(sdev, struct csi_state, sd);
> > +}
> > +
> > +static int mipi_csi2_s_stream(struct v4l2_subdev *sd, int enable)
> > +{
> > + struct csi_state *state = mipi_sd_to_csi2_state(sd);
> > + int ret;
> > +
> > + mipi_csi2_write(state, CSI2RX_IRQ_MASK, 0x008);
> > +
> > + dev_dbg(state->dev, "%s: enable: %d\n", __func__, enable);
> > +
> > + if (enable) {
> > + ret = pm_runtime_get_sync(state->dev);
> > + if (ret < 0) {
> > + pm_runtime_put_noidle(state->dev);
> > + return ret;
> > + }
> > + ret = v4l2_subdev_call(state->src_sd, core,
> > s_power, 1);
> > + if (ret < 0 && ret != -ENOIOCTLCMD)
> > + goto done;
> > + }
> > +
> > + mutex_lock(&state->lock);
> > +
> > + if (enable) {
> > + if (state->state & ST_SUSPENDED) {
> > + ret = -EBUSY;
> > + goto unlock;
> > + }
> > +
> > + mipi_csi2_start_stream(state);
> > + ret = v4l2_subdev_call(state->src_sd, video,
> > s_stream, 1);
> > + if (ret < 0)
> > + goto unlock;
> > +
> > + state->state |= ST_STREAMING;
> > + } else {
> > + v4l2_subdev_call(state->src_sd, video, s_stream,
> > 0);
> > + ret = v4l2_subdev_call(state->src_sd, core,
> > s_power, 0);
> > + if (ret == -ENOIOCTLCMD)
> > + ret = 0;
> > + mipi_csi2_stop_stream(state);
> > + state->state &= ~ST_STREAMING;
> > + }
> > +
> > +unlock:
> > + mutex_unlock(&state->lock);
> > +
> > +done:
> > + if (!enable || ret < 0)
> > + pm_runtime_put(state->dev);
> > +
> > + return ret;
> > +}
> > +
> > +static struct v4l2_mbus_framefmt *
> > +mipi_csi2_get_format(struct csi_state *state,
> > + struct v4l2_subdev_pad_config *cfg,
> > + enum v4l2_subdev_format_whence which,
> > + unsigned int pad)
> > +{
> > + if (which == V4L2_SUBDEV_FORMAT_TRY)
> > + return v4l2_subdev_get_try_format(&state->sd, cfg,
> > pad);
> > +
> > + return &state->format_mbus;
> > +}
> > +
> > +static int mipi_csi2_init_cfg(struct v4l2_subdev *sd,
> > + struct v4l2_subdev_pad_config *cfg)
> > +{
> > + struct csi_state *state = mipi_sd_to_csi2_state(sd);
> > + struct v4l2_mbus_framefmt *fmt_sink;
> > + struct v4l2_mbus_framefmt *fmt_source;
> > + enum v4l2_subdev_format_whence which;
> > +
> > + which = cfg ? V4L2_SUBDEV_FORMAT_TRY :
> > V4L2_SUBDEV_FORMAT_ACTIVE;
> > + fmt_sink = mipi_csi2_get_format(state, cfg, which,
> > MIPI_CSI2_PAD_SINK);
> > +
> > + fmt_sink->code = MEDIA_BUS_FMT_SGBRG10_1X10;
> > + fmt_sink->width = MIPI_CSI2_DEF_PIX_WIDTH;
> > + fmt_sink->height = MIPI_CSI2_DEF_PIX_HEIGHT;
> > + fmt_sink->field = V4L2_FIELD_NONE;
> > +
> > + fmt_sink->colorspace = V4L2_COLORSPACE_RAW;
> > + fmt_sink->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(fmt_sink-
> > >colorspace);
> > + fmt_sink->ycbcr_enc = V4L2_MAP_YCBCR_ENC_DEFAULT(fmt_sink-
> > >colorspace);
> > + fmt_sink->quantization =
> > + V4L2_MAP_QUANTIZATION_DEFAULT(false, fmt_sink-
> > >colorspace,
> > + fmt_sink->ycbcr_enc);
> > +
> > + /*
> > + * When called from mipi_csi2_subdev_init() to initialize
> > the active
> > + * configuration, cfg is NULL, which indicates there's no
> > source pad
> > + * configuration to set.
> > + */
> > + if (!cfg)
> > + return 0;
> > +
> > + fmt_source = mipi_csi2_get_format(state, cfg, which,
> > MIPI_CSI2_PAD_SOURCE);
> > + *fmt_source = *fmt_sink;
> > +
> > + return 0;
> > +}
> > +
> > +static int mipi_csi2_get_fmt(struct v4l2_subdev *sd,
> > + struct v4l2_subdev_pad_config *cfg,
> > + struct v4l2_subdev_format *sdformat)
> > +{
> > + struct csi_state *state = mipi_sd_to_csi2_state(sd);
> > + struct v4l2_mbus_framefmt *fmt;
> > +
> > + fmt = mipi_csi2_get_format(state, cfg, sdformat->which,
> > sdformat->pad);
> > +
> > + mutex_lock(&state->lock);
> > + sdformat->format = *fmt;
> > + mutex_unlock(&state->lock);
> > +
> > + return 0;
> > +}
> > +
> > +static int mipi_csi2_enum_mbus_code(struct v4l2_subdev *sd,
> > + struct v4l2_subdev_pad_config
> > *cfg,
> > + struct
> > v4l2_subdev_mbus_code_enum *code)
> > +{
> > + struct csi_state *state = mipi_sd_to_csi2_state(sd);
> > +
> > + /*
> > + * We can't transcode in any way, the source format is
> > identical
> > + * to the sink format.
> > + */
> > + if (code->pad == MIPI_CSI2_PAD_SOURCE) {
> > + struct v4l2_mbus_framefmt *fmt;
> > +
> > + if (code->index > 0)
> > + return -EINVAL;
> > +
> > + fmt = mipi_csi2_get_format(state, cfg, code->which,
> > code->pad);
> > + code->code = fmt->code;
> > + return 0;
> > + }
> > +
> > + if (code->pad != MIPI_CSI2_PAD_SINK)
> > + return -EINVAL;
> > +
> > + if (code->index >= ARRAY_SIZE(mipi_csi2_formats))
> > + return -EINVAL;
> > +
> > + code->code = mipi_csi2_formats[code->index].code;
> > +
> > + return 0;
> > +}
> > +
> > +static int mipi_csi2_set_fmt(struct v4l2_subdev *sd,
> > + struct v4l2_subdev_pad_config *cfg,
> > + struct v4l2_subdev_format *sdformat)
> > +{
> > + struct csi_state *state = mipi_sd_to_csi2_state(sd);
> > + struct csi2_pix_format const *csi2_fmt;
> > + struct v4l2_mbus_framefmt *fmt;
> > +
> > + /*
> > + * The device can't transcode in any way, the source format
> > can't be
> > + * modified.
> > + */
> > + if (sdformat->pad == MIPI_CSI2_PAD_SOURCE)
> > + return mipi_csi2_get_fmt(sd, cfg, sdformat);
> > +
> > + if (sdformat->pad != MIPI_CSI2_PAD_SINK)
> > + return -EINVAL;
> > +
> > + csi2_fmt = find_csi2_format(sdformat->format.code);
> > + if (!csi2_fmt) {
> > + dev_err(state->dev, "no format found based on code
> > %d\n",
> > + sdformat->format.code);
> > + csi2_fmt = &mipi_csi2_formats[0];
> > + }
> > +
> > + fmt = mipi_csi2_get_format(state, cfg, sdformat->which,
> > sdformat->pad);
> > +
> > + mutex_lock(&state->lock);
> > +
> > + fmt->code = csi2_fmt->code;
> > + fmt->width = sdformat->format.width;
> > + fmt->height = sdformat->format.height;
> > +
> > + sdformat->format = *fmt;
> > +
> > + /* Propagate the format from sink to source. */
> > + fmt = mipi_csi2_get_format(state, cfg, sdformat->which,
> > + MIPI_CSI2_PAD_SOURCE);
> > + *fmt = sdformat->format;
> > +
> > + /* Store the CSI2 format descriptor for active formats. */
> > + if (sdformat->which == V4L2_SUBDEV_FORMAT_ACTIVE)
> > + state->csi2_fmt = csi2_fmt;
> > +
> > + mutex_unlock(&state->lock);
> > +
> > + /*
> > https://community.nxp.com/t5/i-MX-Processors/Explenation-for-HS-SETTLE-parameter-in-MIPI-CSI-D-PHY-registers/m-p/764275/highlight/true#M118744
> > */
> > + if (sdformat->format.width * sdformat->format.height > 720
> > * 480)
> > + state->hs_settle = 0x9;
> > + else
> > + state->hs_settle = 0x14;
> > +
> > + state->send_level = 64;
> > +
> > + dev_dbg(state->dev,
> > + "%s: format %dx%d send_level %d hs_settle 0x%X\n",
> > __func__,
> > + sdformat->format.width, sdformat->format.height,
> > + state->send_level, state->hs_settle);
> > +
> > + return 0;
> > +}
> > +
> > +static int mipi_csi2_log_status(struct v4l2_subdev *sd)
> > +{
> > + struct csi_state *state = mipi_sd_to_csi2_state(sd);
> > +
> > + mutex_lock(&state->lock);
> > + mutex_unlock(&state->lock);
> > +
> > + return 0;
>
> Please don't push stub code upstream.
>
> > +}
> > +
> > +static const struct v4l2_subdev_core_ops mipi_csi2_core_ops = {
> > + .log_status = mipi_csi2_log_status,
> > +};
> > +
> > +static const struct v4l2_subdev_video_ops mipi_csi2_video_ops = {
> > + .s_stream = mipi_csi2_s_stream,
> > +};
> > +
> > +static const struct v4l2_subdev_pad_ops mipi_csi2_pad_ops = {
> > + .init_cfg = mipi_csi2_init_cfg,
> > + .enum_mbus_code = mipi_csi2_enum_mbus_code,
> > + .get_fmt = mipi_csi2_get_fmt,
> > + .set_fmt = mipi_csi2_set_fmt,
> > +};
> > +
> > +static const struct v4l2_subdev_ops mipi_csi2_subdev_ops = {
> > + .core = &mipi_csi2_core_ops,
> > + .video = &mipi_csi2_video_ops,
> > + .pad = &mipi_csi2_pad_ops,
> > +};
> > +
> > +/* ---------------------------------------------------------------
> > --------------
> > + * Media entity operations
> > + */
> > +
> > +static int mipi_csi2_link_setup(struct media_entity *entity,
> > + const struct media_pad *local_pad,
> > + const struct media_pad *remote_pad,
> > u32 flags)
> > +{
> > + struct v4l2_subdev *sd =
> > media_entity_to_v4l2_subdev(entity);
> > + struct csi_state *state = mipi_sd_to_csi2_state(sd);
> > + struct v4l2_subdev *remote_sd;
> > +
> > + dev_dbg(state->dev, "link setup %s -> %s", remote_pad-
> > >entity->name,
> > + local_pad->entity->name);
> > +
> > + /* We only care about the link to the source. */
> > + if (!(local_pad->flags & MEDIA_PAD_FL_SINK))
> > + return 0;
> > +
> > + remote_sd = media_entity_to_v4l2_subdev(remote_pad-
> > >entity);
> > +
> > + if (flags & MEDIA_LNK_FL_ENABLED) {
> > + if (state->src_sd)
> > + return -EBUSY;
> > +
> > + state->src_sd = remote_sd;
> > + } else {
> > + state->src_sd = NULL;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static const struct media_entity_operations mipi_csi2_entity_ops =
> > {
> > + .link_setup = mipi_csi2_link_setup,
> > + .link_validate = v4l2_subdev_link_validate,
> > + .get_fwnode_pad = v4l2_subdev_get_fwnode_pad_1_to_1,
> > +};
> > +
> > +/* ---------------------------------------------------------------
> > --------------
> > + * Async subdev notifier
> > + */
> > +
> > +static struct csi_state *
> > +mipi_notifier_to_csi2_state(struct v4l2_async_notifier *n)
> > +{
> > + return container_of(n, struct csi_state, notifier);
> > +}
> > +
> > +static int mipi_csi2_notify_bound(struct v4l2_async_notifier
> > *notifier,
> > + struct v4l2_subdev *sd,
> > + struct v4l2_async_subdev *asd)
> > +{
> > + struct csi_state *state =
> > mipi_notifier_to_csi2_state(notifier);
> > + struct media_pad *sink = &state-
> > >sd.entity.pads[MIPI_CSI2_PAD_SINK];
> > +
> > + return v4l2_create_fwnode_links_to_pad(sd, sink, 0);
> > +}
> > +
> > +static const struct v4l2_async_notifier_operations
> > mipi_csi2_notify_ops = {
> > + .bound = mipi_csi2_notify_bound,
> > +};
> > +
> > +static int mipi_csi2_async_register(struct csi_state *state)
> > +{
> > + struct v4l2_fwnode_endpoint vep = {
> > + .bus_type = V4L2_MBUS_CSI2_DPHY,
> > + };
> > + struct v4l2_async_subdev *asd;
> > + struct fwnode_handle *ep;
> > + unsigned int i;
> > + int ret;
> > +
> > + v4l2_async_notifier_init(&state->notifier);
> > +
> > + ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(state-
> > >dev), 0, 0,
> > +
> > FWNODE_GRAPH_ENDPOINT_NEXT);
> > + if (!ep)
> > + return -ENOTCONN;
> > +
> > + ret = v4l2_fwnode_endpoint_parse(ep, &vep);
> > + if (ret)
> > + goto err_parse;
> > +
> > + for (i = 0; i < vep.bus.mipi_csi2.num_data_lanes; ++i) {
> > + if (vep.bus.mipi_csi2.data_lanes[i] != i + 1) {
> > + dev_err(state->dev,
> > + "data lanes reordering is not
> > supported");
> > + goto err_parse;
>
> Missing error code.
>
> > + }
> > + }
> > +
> > + state->bus = vep.bus.mipi_csi2;
> > +
> > + dev_dbg(state->dev, "data lanes: %d\n", state-
> > >bus.num_data_lanes);
> > + dev_dbg(state->dev, "flags: 0x%08x\n", state->bus.flags);
> > +
> > + asd = v4l2_async_notifier_add_fwnode_remote_subdev(&state-
> > >notifier,
> > + ep,
> > struct v4l2_async_subdev);
> > + if (IS_ERR(asd)) {
> > + ret = PTR_ERR(asd);
> > + goto err_parse;
> > + }
> > +
> > + fwnode_handle_put(ep);
> > +
> > + state->notifier.ops = &mipi_csi2_notify_ops;
> > +
> > + ret = v4l2_async_subdev_notifier_register(&state->sd,
> > &state->notifier);
> > + if (ret)
> > + return ret;
> > +
> > + return v4l2_async_register_subdev(&state->sd);
> > +
> > +err_parse:
> > + fwnode_handle_put(ep);
> > +
> > + return ret;
> > +}
> > +
> > +/* ---------------------------------------------------------------
> > --------------
> > + * Suspend/resume
> > + */
> > +
> > +static int mipi_csi2_pm_suspend(struct device *dev, bool runtime)
> > +{
> > + struct v4l2_subdev *sd = dev_get_drvdata(dev);
> > + struct csi_state *state = mipi_sd_to_csi2_state(sd);
> > + int ret = 0;
> > +
> > + mutex_lock(&state->lock);
> > + if (state->state & ST_POWERED) {
> > + mipi_csi2_stop_stream(state);
> > + mipi_csi2_clk_disable(state);
> > + state->state &= ~ST_POWERED;
> > + if (!runtime)
> > + state->state |= ST_SUSPENDED;
> > + }
> > +
> > + mutex_unlock(&state->lock);
> > +
> > + ret = icc_set_bw(state->icc_path, 0, 0);
> > + if (ret)
> > + dev_err(dev, "icc_set_bw failed with %d\n", ret);
> > +
> > + return ret ? -EAGAIN : 0;
> > +}
> > +
> > +static int mipi_csi2_pm_resume(struct device *dev, bool runtime)
> > +{
> > + struct v4l2_subdev *sd = dev_get_drvdata(dev);
> > + struct csi_state *state = mipi_sd_to_csi2_state(sd);
> > + int ret = 0;
> > +
> > + ret = icc_set_bw(state->icc_path, 0, state->icc_path_bw);
> > + if (ret) {
> > + dev_err(dev, "icc_set_bw failed with %d\n", ret);
> > + return ret;
> > + }
> > +
> > + mutex_lock(&state->lock);
> > + if (!runtime && !(state->state & ST_SUSPENDED))
> > + goto unlock;
> > +
> > + if (!(state->state & ST_POWERED)) {
> > + state->state |= ST_POWERED;
> > + ret = mipi_csi2_clk_enable(state);
> > + }
> > + if (state->state & ST_STREAMING)
> > + mipi_csi2_start_stream(state);
> > +
> > + state->state &= ~ST_SUSPENDED;
> > +
> > +unlock:
> > + mutex_unlock(&state->lock);
> > +
> > + return ret ? -EAGAIN : 0;
> > +}
> > +
> > +static int __maybe_unused mipi_csi2_suspend(struct device *dev)
> > +{
> > + return mipi_csi2_pm_suspend(dev, false);
> > +}
> > +
> > +static int __maybe_unused mipi_csi2_resume(struct device *dev)
> > +{
> > + return mipi_csi2_pm_resume(dev, false);
> > +}
> > +
> > +static int __maybe_unused mipi_csi2_runtime_suspend(struct device
> > *dev)
> > +{
> > + return mipi_csi2_pm_suspend(dev, true);
> > +}
> > +
> > +static int __maybe_unused mipi_csi2_runtime_resume(struct device
> > *dev)
> > +{
> > + return mipi_csi2_pm_resume(dev, true);
> > +}
> > +
> > +static const struct dev_pm_ops mipi_csi2_pm_ops = {
> > + SET_RUNTIME_PM_OPS(mipi_csi2_runtime_suspend,
> > mipi_csi2_runtime_resume,
> > + NULL)
> > + SET_SYSTEM_SLEEP_PM_OPS(mipi_csi2_suspend,
> > mipi_csi2_resume)
> > +};
> > +
> > +/* ---------------------------------------------------------------
> > --------------
> > + * Probe/remove & platform driver
> > + */
> > +
> > +static int mipi_csi2_subdev_init(struct csi_state *state)
> > +{
> > + struct v4l2_subdev *sd = &state->sd;
> > +
> > + v4l2_subdev_init(sd, &mipi_csi2_subdev_ops);
> > + sd->owner = THIS_MODULE;
> > + snprintf(sd->name, sizeof(sd->name), "%s.%d",
> > + MIPI_CSI2_SUBDEV_NAME, state->index);
> > +
> > + sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> > + sd->ctrl_handler = NULL;
> > +
> > + sd->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
> > + sd->entity.ops = &mipi_csi2_entity_ops;
> > +
> > + sd->dev = state->dev;
> > +
> > + state->csi2_fmt = &mipi_csi2_formats[0];
> > + mipi_csi2_init_cfg(sd, NULL);
> > +
> > + state->pads[MIPI_CSI2_PAD_SINK].flags = MEDIA_PAD_FL_SINK
> > + |
> > MEDIA_PAD_FL_MUST_CONNECT;
> > + state->pads[MIPI_CSI2_PAD_SOURCE].flags =
> > MEDIA_PAD_FL_SOURCE
> > + |
> > MEDIA_PAD_FL_MUST_CONNECT;
> > + return media_entity_pads_init(&sd->entity,
> > MIPI_CSI2_PADS_NUM,
> > + state->pads);
> > +}
> > +
> > +static int init_icc(struct platform_device *pdev)
> > +{
> > + struct v4l2_subdev *sd = dev_get_drvdata(&pdev->dev);
> > + struct csi_state *state = mipi_sd_to_csi2_state(sd);
> > + int ret;
> > +
> > + /* Optional interconnect request */
> > + state->icc_path = of_icc_get(&pdev->dev, "dram");
> > + if (IS_ERR(state->icc_path)) {
> > + ret = PTR_ERR(state->icc_path);
> > + if (ret == -EPROBE_DEFER)
> > + return ret;
> > +
> > + state->icc_path = NULL;
> > + return 0;
>
> Normally if a feature is optional feature then it will return NULL if
> the option is disabled and error pointers if there is an error. And
> that's true here too because of_icc_get() will return NULL if it's
> disabled.
>
> And normally if there is an error then we treat it like an error
> instead
> of just disabling it. The user can then fix the error or disable the
> feature and try again. It's like at a restaurant if you order
> pancakes
> but they don't have any, they don't silently replace it with fried
> egg
> because pancakes are not a requirement for life.
>
> So my instinct is that this should be written as:
>
> state->icc_path = of_icc_get(&pdev->dev, "dram");
> if (PTR_ERR_OR_NULL(state->icc_path))
> return PTR_ERR(state->icc_path);
>
> > + }
> > +
> > + state->icc_path_bw = MBps_to_icc(700);
> > +
> > + ret = icc_set_bw(state->icc_path, 0, state->icc_path_bw);
> > + if (ret) {
> > + dev_err(&pdev->dev, "icc_set_bw failed with %d\n",
> > ret);
> > + return ret;
>
> Probably we need to call icc_put(state->icc_path) before returning?
> I wish there were a of_icc_put() function even if it were very
> simple:
>
> void of_icc_put(struct icc_path *path)
> {
> icc_put(path);
> }
>
> There needs to be a free function for init_icc() as well:
>
> void release_icc(struct platform_device *pdev)
> {
> struct v4l2_subdev *sd = dev_get_drvdata(&pdev->dev);
> struct csi_state *state = mipi_sd_to_csi2_state(sd);
>
> icc_put(state->path);
> }
>
> We could call it from probe if mipi_csi2_pm_resume() fails.
> Currently
> that leaks. Also we could call it from the remove function instead
> of
> calling icc_put() directly.
>
>
> regards,
> dan carpenter
Thank you very much Dan for taking the time! I'll adjust and fix
everything you point out for the next revision.
regards,
martin
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