On 12/02/2025 20:56, Sebastian LaVine wrote: > +static int imx728_detect(struct imx728 *imx728) > +{ > + int ret = 0; > + u64 minor, major; > + > + cci_read(imx728->regmap, IMX728_REG_VMAJOR, &major, &ret); > + if (ret != 0) { > + dev_err(imx728->dev, "Could not read PARAM_MAJOR_VER!"); > + return ret; > + } > + cci_read(imx728->regmap, IMX728_REG_VMINOR, &minor, &ret); > + if (ret != 0) { > + dev_err(imx728->dev, "Could not read PARAM_MINOR_VER!"); > + return ret; > + } > + dev_dbg(imx728->dev, "Got version: %lld.%lld", major, minor); > + > + return 0; > +} > + > +static int imx728_reset(struct imx728 *imx728) > +{ > + > + int ret = 0; > + > + // Prefer hardware reset if available. > + if (!IS_ERR_OR_NULL(imx728->reset_gpio)) { Here can be ERR (although why?) but... > + gpiod_set_value_cansleep(imx728->reset_gpio, 1); > + usleep_range(1000, 10000); > + gpiod_set_value_cansleep(imx728->reset_gpio, 0); > + msleep(100); > + } else { > + // Software reset. > + cci_write(imx728->regmap, IMX728_REG_RESET_0, 0xc3, &ret); > + cci_update_bits(imx728->regmap, IMX728_REG_RESET_1, 0x1, 0x1, &ret); > + msleep(100); > + } > + > + return ret; > +} > + > +static int imx728_power_on(struct imx728 *imx728) > +{ > + int ret; > + > + ret = clk_prepare_enable(imx728->clk); > + if (ret < 0) > + return ret; > + > + imx728_reset(imx728); > + return 0; > +} > + > +static int imx728_power_off(struct imx728 *imx728) > +{ > + > + if (imx728->reset_gpio) { Here cannot. > + gpiod_set_value_cansleep(imx728->reset_gpio, 1); > + > + usleep_range(1, 10); > + } > + clk_disable_unprepare(imx728->clk); > + return 0; > +} > + ... > + > +static int imx728_set_stream(struct v4l2_subdev *sd, int enable) > +{ > + struct imx728 *imx728 = to_imx728(sd); > + int ret; > + > + mutex_lock(&imx728->lock); Just use guard. That's actually perfect candidate. > + if (imx728->streaming == enable) { > + mutex_unlock(&imx728->lock); > + return 0; > + } > + > + if (enable) { > + ret = pm_runtime_get_sync(imx728->dev); > + if (ret < 0) { > + pm_runtime_put_noidle(imx728->dev); > + goto err_unlock; > + } > + > + ret = imx728_start_stream(imx728); > + if (ret < 0) > + goto err_runtime_put; > + } else { > + ret = imx728_stop_stream(imx728); > + if (ret < 0) > + goto err_runtime_put; > + pm_runtime_mark_last_busy(imx728->dev); > + pm_runtime_put_autosuspend(imx728->dev); > + } > + > + imx728->streaming = enable; > + > + __v4l2_ctrl_grab(imx728->ctrl.h_flip, enable); > + __v4l2_ctrl_grab(imx728->ctrl.v_flip, enable); > + > + mutex_unlock(&imx728->lock); > + > + return 0; > + > +err_runtime_put: > + pm_runtime_put(imx728->dev); > + > +err_unlock: > + mutex_unlock(&imx728->lock); > + dev_err(imx728->dev, > + "%s: failed to setup streaming %d\n", __func__, ret); > + return ret; > +} > + > +static const struct v4l2_subdev_core_ops imx728_core_ops = { > + .subscribe_event = v4l2_ctrl_subdev_subscribe_event, > + .unsubscribe_event = v4l2_event_subdev_unsubscribe, > +}; > + > +static const struct v4l2_subdev_video_ops imx728_subdev_video_ops = { > + .s_stream = imx728_set_stream, > +}; > + > +static const struct v4l2_subdev_pad_ops imx728_subdev_pad_ops = { > + .enum_frame_size = imx728_enum_frame_sizes, > + .enum_mbus_code = imx728_enum_mbus_code, > + .get_fmt = v4l2_subdev_get_fmt, > + .get_frame_desc = imx728_get_frame_desc, > + .get_frame_interval = imx728_get_frame_interval, > + .get_selection = imx728_get_selection, > + .set_fmt = imx728_set_fmt, > + .set_frame_interval = imx728_set_frame_interval, > + .set_routing = imx728_set_routing, > +}; > + > +static const struct v4l2_subdev_ops imx728_subdev_ops = { > + .core = &imx728_core_ops, > + .video = &imx728_subdev_video_ops, > + .pad = &imx728_subdev_pad_ops, > +}; > + > +static const struct v4l2_subdev_internal_ops imx728_internal_ops = { > + .init_state = imx728_init_state, > +}; > + > + > +static const struct v4l2_ctrl_ops imx728_ctrl_ops = { > + .s_ctrl = imx728_set_ctrl, > +}; > + > +static int imx728_probe(struct i2c_client *client) > +{ > + struct imx728 *imx728; > + struct v4l2_subdev *sd; > + struct v4l2_ctrl_handler *ctrl_hdr; > + int ret; > + > + imx728 = devm_kzalloc(&client->dev, sizeof(*imx728), GFP_KERNEL); > + if (!imx728) > + return -ENOMEM; > + > + imx728->dev = &client->dev; > + > + imx728->regmap = devm_cci_regmap_init_i2c(client, 16); > + if (IS_ERR(imx728->regmap)) > + return PTR_ERR(imx728->regmap); > + > + imx728->reset_gpio = devm_gpiod_get_optional(imx728->dev, > + "reset", GPIOD_OUT_LOW); > + if (IS_ERR(imx728->reset_gpio)) > + return PTR_ERR(imx728->reset_gpio); So can it be ERR after that point? Looks like not. Best regards, Krzysztof