Re: [PATCH v3 1/3] iio: adc: at91-sama5d2_adc: fix differential channels in triggered mode

[Eugen.Hristev]

On 02.02.2020 13:02, Jonathan Cameron wrote:
> On Tue, 28 Jan 2020 12:57:39 +0000
> <Eugen.Hristev@xxxxxxxxxxxxx> wrote:
> 
>> From: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
>>
>> The differential channels require writing the channel offset register (COR).
>> Otherwise they do not work in differential mode.
>> The configuration of COR is missing in triggered mode.
>>
>> Fixes: 5e1a1da0f8c9 ("iio: adc: at91-sama5d2_adc: add hw trigger and buffer support")
>> Signed-off-by: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
> Applied to the fixes-togreg branch of iio.git.  Normally I avoid rebasing that
> branch but I may do so this time given it's currently mid merge window.
> 
> The other two patches will have to wait for this one to get upstream of
> my togreg branch which will take a few weeks.
> 
> Please give me a poke if I seem to have forgotten about them!
> 

Poke !

Eugen

> Thanks,
> 
> Jonathan
> 
>> ---
>> Changes in v2:
>> - moved to the start of the list
>>
>>   drivers/iio/adc/at91-sama5d2_adc.c | 15 +++++++++++++++
>>   1 file changed, 15 insertions(+)
>>
>> diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
>> index e1850f3..2a6950a 100644
>> --- a/drivers/iio/adc/at91-sama5d2_adc.c
>> +++ b/drivers/iio/adc/at91-sama5d2_adc.c
>> @@ -723,6 +723,7 @@ static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
>>
>>        for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) {
>>                struct iio_chan_spec const *chan = at91_adc_chan_get(indio, bit);
>> +             u32 cor;
>>
>>                if (!chan)
>>                        continue;
>> @@ -732,6 +733,20 @@ static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
>>                        continue;
>>
>>                if (state) {
>> +                     cor = at91_adc_readl(st, AT91_SAMA5D2_COR);
>> +
>> +                     if (chan->differential)
>> +                             cor |= (BIT(chan->channel) |
>> +                                     BIT(chan->channel2)) <<
>> +                                     AT91_SAMA5D2_COR_DIFF_OFFSET;
>> +                     else
>> +                             cor &= ~(BIT(chan->channel) <<
>> +                                    AT91_SAMA5D2_COR_DIFF_OFFSET);
>> +
>> +                     at91_adc_writel(st, AT91_SAMA5D2_COR, cor);
>> +             }
>> +
>> +             if (state) {
>>                        at91_adc_writel(st, AT91_SAMA5D2_CHER,
>>                                        BIT(chan->channel));
>>                        /* enable irq only if not using DMA */
>