linux-kernel - [PATCH 4.4 060/160] iio: adc: at91: fix acking DRDY irq on simple conversions

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 19 Nov 2018 17:28:19 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Maxime Ripard <maxime.ripard@...tlin.com>,
        Eugen Hristev <eugen.hristev@...rochip.com>,
        Ludovic Desroches <ludovic.desroches@...rochip.com>,
        Stable@...r.kernel.org,
        Jonathan Cameron <Jonathan.Cameron@...wei.com>
Subject: [PATCH 4.4 060/160] iio: adc: at91: fix acking DRDY irq on simple conversions

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eugen Hristev <eugen.hristev@...rochip.com>

commit bc1b45326223e7e890053cf6266357adfa61942d upstream.

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@...tlin.com>
Signed-off-by: Eugen Hristev <eugen.hristev@...rochip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@...rochip.com>
Cc: <Stable@...r.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@...wei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/iio/adc/at91_adc.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -276,6 +276,8 @@ static void handle_adc_eoc_trigger(int i
 		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);
 	}