On Tue, Sep 10, 2019 at 09:04:46PM +0800, dongchun.zhu@xxxxxxxxxxxx wrote: > From: Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx> > > This patch mainly adds two more sensor modes for OV8856 CMOS image sensor. > That is, the resolution of 1632*1224 and 3264*2448, corresponding to the bayer order of BGGR. > The sensor revision also differs in some OTP register. > +static int __ov8856_power_on(struct ov8856 *ov8856) > +{ > + struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd); > + int ret; > + > + ret = clk_prepare_enable(ov8856->xvclk); > + if (ret < 0) { > + dev_err(&client->dev, "failed to enable xvclk\n"); > + return ret; > + } > + > + gpiod_set_value_cansleep(ov8856->n_shutdn_gpio, GPIOD_OUT_LOW); > + > + ret = regulator_bulk_enable(OV8856_NUM_SUPPLIES, ov8856->supplies); > + if (ret < 0) { > + dev_err(&client->dev, "failed to enable regulators\n"); > + goto disable_clk; > + } > + > + gpiod_set_value_cansleep(ov8856->n_shutdn_gpio, GPIOD_OUT_HIGH); > + > + usleep_range(1400, 1500); This should be commented why this is needed and from where the requirement comes from. Also, not, that 100us, which is only ~7%, is small margin. Recommended one is ~20%. > + > + return 0; > + > +disable_clk: > + clk_disable_unprepare(ov8856->xvclk); > + > + return ret; > +} > + ov8856->is_1B_revision = (val == OV8856_1B_MODULE) ? 1 : 0; !! will give same result without using ternary operator. > + ov8856->xvclk = devm_clk_get(&client->dev, "xvclk"); > + if (IS_ERR(ov8856->xvclk)) { > + dev_err(&client->dev, "failed to get xvclk\n"); > + return -EINVAL; > + } Previously it was optional. How did it work before and why it's not optional? > + ov8856->n_shutdn_gpio = devm_gpiod_get(&client->dev, "reset", > + GPIOD_OUT_LOW); > + if (IS_ERR(ov8856->n_shutdn_gpio)) { > + dev_err(&client->dev, "failed to get reset-gpios\n"); > + return -EINVAL; > + } Ditto. > +static const struct of_device_id ov8856_of_match[] = { > + { .compatible = "ovti,ov8856" }, > + {}, No comma needed for terminator line. > +}; -- With Best Regards, Andy Shevchenko