linux-kernel - [PATCH v2 1/3] iio: adc: at91-sama5d2_adc: fix differential channels in triggered mode

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:   Mon, 13 Jan 2020 12:07:09 +0000
From:   <Eugen.Hristev@...rochip.com>
To:     <jic23@...nel.org>, <linux-iio@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>
CC:     <Ludovic.Desroches@...rochip.com>, <Eugen.Hristev@...rochip.com>
Subject: [PATCH v2 1/3] iio: adc: at91-sama5d2_adc: fix differential channels
 in triggered mode

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

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@...rochip.com>
---
Changes in v2:
- moved to the start of the list

 drivers/iio/adc/at91-sama5d2_adc.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index e1850f3..2a6950a 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 */
-- 
2.7.4