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authorEugen Hristev <eugen.hristev@microchip.com>2020-01-28 13:57:39 +0100
committerJonathan Cameron <Jonathan.Cameron@huawei.com>2020-02-02 12:00:23 +0100
commita500f3bd787f8224341e44b238f318c407b10897 (patch)
tree2fd1d31eb65586125bdea9b50d9884c9713dda1a
parentMerge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rd... (diff)
downloadlinux-a500f3bd787f8224341e44b238f318c407b10897.tar.xz
linux-a500f3bd787f8224341e44b238f318c407b10897.zip
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>
-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 */