Re: [PATCH 07/10] iio: adc: at91-sama5d2_adc: fix differential channels in triggered mode
From: Jonathan Cameron <jic23@kernel.org>
Date: 2019-12-23 12:24:05
Also in:
linux-arm-kernel, linux-iio, linux-rtc, lkml
On Wed, 18 Dec 2019 16:24:02 +0000 [off-list ref] wrote:
From: Eugen Hristev <redacted> 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. Signed-off-by: Eugen Hristev <redacted>
I'm not totally sure whether this predates the changes here, but if it does please pull it to the front of the set and give it a fixes tag. Otherwise, look at merging it in with where-ever it was introduced. Thanks, Jonathan
quoted hunk ↗ jump to hunk
--- drivers/iio/adc/at91-sama5d2_adc.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c index a6b4dff..ccffa48 100644 --- a/drivers/iio/adc/at91-sama5d2_adc.c +++ b/drivers/iio/adc/at91-sama5d2_adc.c@@ -900,6 +900,7 @@ static int at91_adc_buffer_postenable(struct iio_dev *indio) 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;@@ -908,6 +909,17 @@ static int at91_adc_buffer_postenable(struct iio_dev *indio) chan->type == IIO_PRESSURE) continue; + 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); + at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel)); if (use_irq) { at91_adc_writel(st, AT91_SAMA5D2_IER,