linux-kernel - [PATCH AUTOSEL 4.9 33/34] gpiolib: Respect error code of ->get

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Message-ID: <20180915013422.180023-33-alexander.levin@microsoft.com>
Date:   Sat, 15 Sep 2018 01:34:47 +0000
From:   Sasha Levin <Alexander.Levin@...rosoft.com>
To:     "stable@...r.kernel.org" <stable@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
CC:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Mika Westerberg <mika.westerberg@...ux.intel.com>,
        Linus Walleij <linus.walleij@...aro.org>,
        Sasha Levin <Alexander.Levin@...rosoft.com>
Subject: [PATCH AUTOSEL 4.9 33/34] gpiolib: Respect error code of
 ->get_direction()

From: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>

[ Upstream commit 36b312792b97933dc07abe074f50941199bd357c ]

In case we try to lock GPIO pin as IRQ when something going wrong
we print a misleading message.

Correct this by checking an error code from ->get_direction() in
gpiochip_lock_as_irq() and printing a corresponding message.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Cc: Mika Westerberg <mika.westerberg@...ux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@...aro.org>
Signed-off-by: Sasha Levin <alexander.levin@...rosoft.com>
---
 drivers/gpio/gpiolib.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index dd0076497463..f9b3f95253d1 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -2749,6 +2749,12 @@ int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
 	if (!chip->can_sleep && chip->get_direction) {
 		int dir = chip->get_direction(chip, offset);
 
+		if (dir < 0) {
+			chip_err(chip, "%s: cannot get GPIO direction\n",
+				 __func__);
+			return dir;
+		}
+
 		if (dir)
 			clear_bit(FLAG_IS_OUT, &desc->flags);
 		else
-- 
2.17.1