On Mon, 2 Dec 2019 16:36:19 +0100
Couret Charles-Antoine <charles-antoine.couret@xxxxxxxxxxxxx> wrote:
> Le 02/12/2019 à 15:13, Andrea Merello a écrit :
> > drivers/iio/adc/ad7949.c | 22 +++++++++++++++++-----
> > 1 file changed, 17 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/iio/adc/ad7949.c b/drivers/iio/adc/ad7949.c
> > index 5c2b3446fa4a..2c6f60edb7ce 100644
> > --- a/drivers/iio/adc/ad7949.c
> > +++ b/drivers/iio/adc/ad7949.c
> > @@ -89,6 +89,7 @@ static int ad7949_spi_read_channel(struct ad7949_adc_chip *ad7949_adc, int *val,
> > unsigned int channel)
> > {
> > int ret;
> > + int i;
> > int bits_per_word = ad7949_adc->resolution;
> > int mask = GENMASK(ad7949_adc->resolution, 0);
> > struct spi_message msg;
> > @@ -100,12 +101,23 @@ static int ad7949_spi_read_channel(struct ad7949_adc_chip *ad7949_adc, int *val,
> > },
> > };
> >
> > - ret = ad7949_spi_write_cfg(ad7949_adc,
> > - channel << AD7949_OFFSET_CHANNEL_SEL,
> > - AD7949_MASK_CHANNEL_SEL);
> > - if (ret)
> > - return ret;
> > + /*
> > + * 1: write CFG for sample N and read old data (sample N-2)
> > + * 2: if CFG was not changed since sample N-1 then we'll get good data
> > + * at the next xfer, so we bail out now, otherwise we write something
> > + * and we read garbage (sample N-1 configuration).
> > + */
> > + for (i = 0; i < 2; i++) {
> > + ret = ad7949_spi_write_cfg(ad7949_adc,
> > + channel << AD7949_OFFSET_CHANNEL_SEL,
> > + AD7949_MASK_CHANNEL_SEL);
> > + if (ret)
> > + return ret;
> > + if (channel == ad7949_adc->current_channel)
> > + break;
> > + }
> >
> > + /* 3: write something and read actual data */
> > ad7949_adc->buffer = 0;
> > spi_message_init_with_transfers(&msg, tx, 1);
> > ret = spi_sync(ad7949_adc->spi, &msg);
>
> Signed-off-by: Charles-Antoine Couret <charles-antoine.couret@xxxxxxxxxxxxx>
Hi Charles-Antoine,
Why a signed-off-by as opposed to a reviewed-by or similar?
signed-off-by brings some very specific legal implications around Developer
Certificate of Origin, so is normally just the author plus people involved in
the path to upstream (maintainers).
>
> Regards,
> Charles-Antoine Couret
