linux-kernel - [PATCH] can: dev: can_set_termination(): Allow gpio sleep

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Message-Id: <20241121150209.125772-1-nb@tipi-net.de>
Date: Thu, 21 Nov 2024 16:02:09 +0100
From: Nicolai Buchwitz <nb@...i-net.de>
To: Marc Kleine-Budde <mkl@...gutronix.de>,
	Vincent Mailhol <mailhol.vincent@...adoo.fr>,
	Andrew Lunn <andrew+netdev@...n.ch>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Paolo Abeni <pabeni@...hat.com>
Cc: n.buchwitz@...bus.com,
	l.sanfilippo@...bus.com,
	p.rosenberger@...bus.com,
	stable@...r.kernel.org,
	Nicolai Buchwitz <nb@...i-net.de>,
	linux-can@...r.kernel.org,
	netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH] can: dev: can_set_termination(): Allow gpio sleep

The current implementation of can_set_termination() sets the GPIO in a
context which cannot sleep. This is an issue if the GPIO controller can
sleep (e.g. since the concerning GPIO expander is connected via SPI or
I2C). Thus, if the termination resistor is set (eg. with ip link),
a warning splat will be issued in the kernel log.

Fix this by setting the termination resistor with
gpiod_set_value_cansleep() which instead of gpiod_set_value() allows it to
sleep.

Cc: stable@...r.kernel.org
Signed-off-by: Nicolai Buchwitz <nb@...i-net.de>
---
 drivers/net/can/dev/dev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/can/dev/dev.c b/drivers/net/can/dev/dev.c
index 6792c14fd7eb..681643ab3780 100644
--- a/drivers/net/can/dev/dev.c
+++ b/drivers/net/can/dev/dev.c
@@ -468,7 +468,7 @@ static int can_set_termination(struct net_device *ndev, u16 term)
 	else
 		set = 0;
 
-	gpiod_set_value(priv->termination_gpio, set);
+	gpiod_set_value_cansleep(priv->termination_gpio, set);
 
 	return 0;
 }
-- 
2.39.5