Hi Bingbu,
On Fri, Sep 21, 2018 at 03:20:19PM +0800, Bing Bu Cao wrote:
...
> >> + try_fmt->field = V4L2_FIELD_NONE;
> >> +
> >> + mutex_unlock(&imx319->mutex);
> >> +
> >> + return 0;
> >> +}
> >> +
> >> +static int imx319_update_digital_gain(struct imx319 *imx319, u32 d_gain)
> >> +{
> >> + int ret;
> >> +
> >> + ret = imx319_write_reg(imx319, IMX319_REG_DPGA_USE_GLOBAL_GAIN, 1, 1);
> >> + if (ret)
> >> + return ret;
> > You could do this write right after powering the sensor on, couldn't you?
> Sakari,
> Use IMX319_REG_DPGA_USE_GLOBAL_GAIN to do digital gain control, 1 for all
> color and 0 for by color. For all color, use register
> IMX319_REG_DIG_GAIN_GLOBAL to set the digital gain value, otherwise use
> other registers below. By default the digital gain select is not set and
> the gain will be set by color via setting register 0x0210, 0x0212,
> 0x0213, these registers were set during powering on. So I prefer to only
> change the default digital gain control if any digital gain request.
>
> Does this make sense?
Why are per-component gains used at all when they always have the same
value and the sensor supports global gain?
--
Kind regards,
Sakari Ailus
sakari.ailus@xxxxxxxxxxxxxxx
