On 09/21/2018 03:41 PM, Sakari Ailus wrote:
> 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?
I see that both the per-color and all-color gains are set during powering on.
I think they are from the reference settings from vendor, let me try to move
this control selection into streaming ops.
Thanks!
>
