| Message ID | 1513955241-10985-12-git-send-email-eugen.hristev@microchip.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, 22 Dec 2017 17:07:18 +0200 Eugen Hristev <eugen.hristev@microchip.com> wrote: > Optimize the scan index for the differential channels. Before, it > was single channel count + index of the first single channel > number of the differential pair. (e.g. 11+0, +2, +4, etc.) > Divide that number by two (since it's always even), and add it up > as a scan index to have consecutive numbered channels in the > index. Why? This is odd as it stands, but that isn't a strong enough reason to fix it. This is making a userspace ABI change. We need a very strong argument for why it is necessary and also why existing userspace won't care. > > Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com> > --- > drivers/iio/adc/at91-sama5d2_adc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c > index 7b9febc..9610393 100644 > --- a/drivers/iio/adc/at91-sama5d2_adc.c > +++ b/drivers/iio/adc/at91-sama5d2_adc.c > @@ -209,7 +209,7 @@ > .channel = num, \ > .channel2 = num2, \ > .address = addr, \ > - .scan_index = num + AT91_SAMA5D2_SINGLE_CHAN_CNT, \ > + .scan_index = (num >> 1) + AT91_SAMA5D2_SINGLE_CHAN_CNT,\ > .scan_type = { \ > .sign = 's', \ > .realbits = 12, \ -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c index 7b9febc..9610393 100644 --- a/drivers/iio/adc/at91-sama5d2_adc.c +++ b/drivers/iio/adc/at91-sama5d2_adc.c @@ -209,7 +209,7 @@ .channel = num, \ .channel2 = num2, \ .address = addr, \ - .scan_index = num + AT91_SAMA5D2_SINGLE_CHAN_CNT, \ + .scan_index = (num >> 1) + AT91_SAMA5D2_SINGLE_CHAN_CNT,\ .scan_type = { \ .sign = 's', \ .realbits = 12, \
Optimize the scan index for the differential channels. Before, it was single channel count + index of the first single channel number of the differential pair. (e.g. 11+0, +2, +4, etc.) Divide that number by two (since it's always even), and add it up as a scan index to have consecutive numbered channels in the index. Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com> --- drivers/iio/adc/at91-sama5d2_adc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)