On Mon, Nov 04, 2019 at 06:57:13PM +0800, Dongchun Zhu wrote: > Add a V4L2 sub-device driver for OV02A10 image sensor. > The OV02A10 is a 1/5" CMOS sensor from Omnivision, supporting > output format: 10-bit RAW. > > This chip has a single MIPI lane interface and use the I2C bus > for control and the CSI-2 bus for data. > +/* Bit[7] clock HS mode enable > + * 0: Clock continue > + * 1: Clock HS > + * Bit[6:2] HS VOD adjust > + * Bit[1:0] P VHI adjust > + */ > +#define REG_HS_MODE_BLC 0x9d > + > +#define CLOCK_HS_MODE_ENABLE BIT(7) > +#define CLOCK_HS_VOD_ADJUST (BIT(6) | BIT(5) | BIT(4) | BIT(3) | BIT(2)) GENMASK() > +#define OV02A10_MASK_8_BITS 0xff GENMASK() > +#define OV02A10_LINK_FREQ_390MHZ 390000000ULL Can't we publish HZ_PER_MHZ for wider use (currently in phy-stm32-usbphyc.c and hid-sensor-attributes.c) and use here something like (390 * HZ_PER_MHZ)? > +#define OV02A10_ECLK_FREQ 24000000 Ditto. > +static const s64 link_freq_menu_items[] = { > + OV02A10_LINK_FREQ_390MHZ Better to keep comma here. > +}; > +{ > + struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev); > + int ret; > + > + ret = i2c_smbus_read_byte_data(client, reg); > + if (ret >= 0) { > + *val = (unsigned char)ret; > + ret = 0; > + } Why not to use classical pattern if (ret < 0) return ret; ... return 0; ? > + > + return ret; > +} > +static int ov02a10_mod_reg(struct ov02a10 *ov02a10, u8 reg, u8 mask, u8 val) > +{ > + struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev); > + u8 readval; > + int ret; > + > + ret = ov02a10_read_smbus(ov02a10, reg, &readval); > + if (ret) > + return ret; > + > + readval &= ~mask; > + val &= mask; > + val |= readval; Why not to use classical pattern val = (readval & ~mask) | (val & mask); ? > + > + return i2c_smbus_write_byte_data(client, reg, val); > +} > +{ > + struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev); > + u16 id; > + u8 pid = 0; > + u8 ver = 0; Useless assignments. > + int ret; > + > + /* Check sensor revision */ > + ret = ov02a10_read_smbus(ov02a10, OV02A10_REG_CHIP_ID_H, &pid); > + if (ret) > + return ret; > + > + ret = ov02a10_read_smbus(ov02a10, OV02A10_REG_CHIP_ID_L, &ver); > + if (ret) > + return ret; > + > + id = OV02A10_ID(pid, ver); > + if (id != CHIP_ID) { > + dev_err(&client->dev, "Unexpected sensor id(%04x)\n", id); > + return -EINVAL; > + } > + > + dev_dbg(&client->dev, "Detected OV%04X sensor\n", id); > + > + return 0; > +} > + int ret = 0; Useless assignment... > + > + dev_dbg(&client->dev, "ov02a10 s_stream (%d)\n", on); > + mutex_lock(&ov02a10->mutex); > + > + if (ov02a10->streaming == on) > + goto unlock_and_return; > + > + if (on) { > + ret = pm_runtime_get_sync(&client->dev); > + if (ret < 0) { > + pm_runtime_put_noidle(&client->dev); > + goto unlock_and_return; > + } > + > + ret = __ov02a10_start_stream(ov02a10); > + if (ret) { > + __ov02a10_stop_stream(ov02a10); > + ov02a10->streaming = !on; > + goto err_rpm_put; > + } > + } else { > + __ov02a10_stop_stream(ov02a10); > + pm_runtime_put(&client->dev); > + } > + > + ov02a10->streaming = on; > + mutex_unlock(&ov02a10->mutex); > + > + return ret; ...simple use return 0; here. > + > +err_rpm_put: > + pm_runtime_put(&client->dev); > +unlock_and_return: > + mutex_unlock(&ov02a10->mutex); > + > + return ret; > +} > +static int ov02a10_set_ctrl(struct v4l2_ctrl *ctrl) > +{ > + struct ov02a10 *ov02a10 = container_of(ctrl->handler, > + struct ov02a10, ctrl_handler); > + struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev); > + s64 max_expo; > + int ret = 0; Wouldn't be better to have this under `default` case below? > + > + /* Propagate change of current control to all related controls */ > + if (ctrl->id == V4L2_CID_VBLANK) { > + /* Update max exposure while meeting expected vblanking */ > + max_expo = ov02a10->cur_mode->height + ctrl->val - > + OV02A10_EXPOSURE_MAX_MARGIN; > + __v4l2_ctrl_modify_range(ov02a10->exposure, > + ov02a10->exposure->minimum, max_expo, > + ov02a10->exposure->step, > + ov02a10->exposure->default_value); > + } > + > + /* V4L2 controls values will be applied only when power is already up */ > + if (!pm_runtime_get_if_in_use(&client->dev)) > + return 0; > + > + switch (ctrl->id) { > + case V4L2_CID_EXPOSURE: > + ret = ov02a10_set_exposure(ov02a10, ctrl->val); > + break; > + case V4L2_CID_ANALOGUE_GAIN: > + ret = ov02a10_set_gain(ov02a10, ctrl->val); > + break; > + case V4L2_CID_VBLANK: > + ret = ov02a10_set_vblank(ov02a10, ctrl->val); > + break; > + case V4L2_CID_TEST_PATTERN: > + ret = ov02a10_set_test_pattern(ov02a10, ctrl->val); > + break; > + }; > + > + pm_runtime_put(&client->dev); > + > + return ret; > +} > +{ > + struct fwnode_handle *ep; > + struct fwnode_handle *fwnode = dev_fwnode(dev); > + struct v4l2_fwnode_endpoint bus_cfg = { > + .bus_type = V4L2_MBUS_CSI2_DPHY > + }; > + unsigned int i, j; > + int ret; > + I would rather expect fwnode assignment here to understand immediately from where it has been derived. Though it's up to maintainers. > + if (!fwnode) > + return -ENXIO; > + > + ep = fwnode_graph_get_next_endpoint(fwnode, NULL); > + if (!ep) > + return -ENXIO; > + > + ret = v4l2_fwnode_endpoint_alloc_parse(ep, &bus_cfg); > + fwnode_handle_put(ep); > + if (ret) > + return ret; > + > + /* Optional indication of mipi clock lane mode */ > + if (bus_cfg.bus.mipi_csi2.flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK) > + ov02a10->mipi_clock_hs_mode_enable = true; > + > + if (!bus_cfg.nr_of_link_frequencies) { > + dev_err(dev, "no link frequencies defined"); > + ret = -EINVAL; > + goto check_hwcfg_error; > + } This is redundant check. You have done the similar below when comparing j to nr_of_link_frequencies. > + > + for (i = 0; i < ARRAY_SIZE(link_freq_menu_items); i++) { > + for (j = 0; j < bus_cfg.nr_of_link_frequencies; j++) { > + if (link_freq_menu_items[i] == > + bus_cfg.link_frequencies[j]) > + break; > + } > + > + if (j == bus_cfg.nr_of_link_frequencies) { > + dev_err(dev, "no link frequency %lld supported", > + link_freq_menu_items[i]); > + ret = -EINVAL; > + goto check_hwcfg_error; > + } > + } > + > +check_hwcfg_error: > + v4l2_fwnode_endpoint_free(&bus_cfg); > + > + return ret; > +} > +static int ov02a10_probe(struct i2c_client *client) > +{ > + /* Optional indication of physical rotation of sensor */ > + ret = fwnode_property_read_u32(dev_fwnode(dev), "rotation", > + &rotation); It's perfectly one line. > + if (!ret) { I would rather do two things here: 1/ use the similar pattern as below with messaging if (!ret) { ... } else { dev_dbg(...); } 2/ Actually use positive conditionals if (ret) { ... } else { ... } > + switch (rotation) { > + case 180: > + ov02a10->upside_down = true; > + ov02a10->fmt.code = MEDIA_BUS_FMT_SRGGB10_1X10; > + break; > + case 0: > + break; > + default: > + dev_warn(dev, "%u degrees rotation is not supported, ignoring...\n", > + rotation); > + } > + } > + > + /* Optional indication of HS VOD adjust */ > + ret = fwnode_property_read_u32(dev_fwnode(dev), > + "ovti,hs-vod-adjust", > + &hs_vod_adjust_cnt); > + if (!ret) > + ov02a10->mipi_clock_hs_vod_adjust_cnt = hs_vod_adjust_cnt; > + else > + dev_warn(dev, "failed to get hs vod adjust, using default\n"); > + > + /* Optional indication of mipi tx speed */ > + ret = fwnode_property_read_u32(dev_fwnode(dev), > + "ovti,mipi-tx-speed", > + &clock_lane_tx_speed); > + > + if (!ret) > + ov02a10->mipi_clock_tx_speed = clock_lane_tx_speed; > + else > + dev_warn(dev, "failed to get mipi tx speed, using default\n"); > + /* Get system clock (eclk) */ > + ov02a10->eclk = devm_clk_get(dev, "eclk"); > + if (IS_ERR(ov02a10->eclk)) { > + dev_err(dev, "failed to get eclk\n"); > + return -EINVAL; Why shadow error code? > + } > + ov02a10->pd_gpio = devm_gpiod_get(dev, "powerdown", GPIOD_OUT_HIGH); > + if (IS_ERR(ov02a10->pd_gpio)) { > + dev_err(dev, "failed to get powerdown-gpios\n"); > + return -EINVAL; Ditto. > + } > + ov02a10->n_rst_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW); > + if (IS_ERR(ov02a10->n_rst_gpio)) { > + dev_err(dev, "failed to get reset-gpios\n"); > + return -EINVAL; Ditto. > + } > +} -- With Best Regards, Andy Shevchenko