aboutsummaryrefslogtreecommitdiff
path: root/drivers/iio/adc
diff options
context:
space:
mode:
authorEugen Hristev <eugen.hristev@microchip.com>2020-01-28 12:57:39 +0000
committerJonathan Cameron <Jonathan.Cameron@huawei.com>2020-02-02 11:00:23 +0000
commita500f3bd787f8224341e44b238f318c407b10897 (patch)
tree2fd1d31eb65586125bdea9b50d9884c9713dda1a /drivers/iio/adc
parent39bed42de2e7d74686a2d5a45638d6a5d7e7d473 (diff)
downloadlinux-a500f3bd787f8224341e44b238f318c407b10897.tar.gz
iio: adc: at91-sama5d2_adc: fix differential channels in triggered mode
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@microchip.com> Cc: <Stable@vger.kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Diffstat (limited to 'drivers/iio/adc')
-rw-r--r--drivers/iio/adc/at91-sama5d2_adc.c15
1 files changed, 15 insertions, 0 deletions
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index a5c7771227d5..9d96f7d08b95 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 */