lkml.org 
[lkml]   [2018]   [Nov]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH AUTOSEL 4.9 11/21] iio: adc: at91: fix acking DRDY irq on simple conversions
Date
From: Eugen Hristev <eugen.hristev@microchip.com>

[ Upstream commit bc1b45326223e7e890053cf6266357adfa61942d ]

When doing simple conversions, the driver did not acknowledge the DRDY irq.
If this irq status is not acked, it will be left pending, and as soon as a
trigger is enabled, the irq handler will be called, it doesn't know why
this status has occurred because no channel is pending, and then it will go
int a irq loop and board will hang.
To avoid this situation, read the LCDR after a raw conversion is done.

Fixes: 0e589d5fb ("ARM: AT91: IIO: Add AT91 ADC driver.")
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iio/adc/at91_adc.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index 1ba69bbc3142..e3e2155b0386 100644
--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -280,6 +280,8 @@ static void handle_adc_eoc_trigger(int irq, struct iio_dev *idev)
iio_trigger_poll(idev->trig);
} else {
st->last_value = at91_adc_readl(st, AT91_ADC_CHAN(st, st->chnb));
+ /* Needed to ACK the DRDY interruption */
+ at91_adc_readl(st, AT91_ADC_LCDR);
st->done = true;
wake_up_interruptible(&st->wq_data_avail);
}
--
2.17.1
\
 
 \ /
  Last update: 2018-11-04 14:59    [W:2.731 / U:1.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site