From: Axel Lin <axel.lin@ingics.com>
Date: Fri, 30 Jan 2015 10:26:25 +0000 (+0800)
Subject: gpio: mb86s70: Return error if requesting an already assigned gpio
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=fd9c963c5661af3403e77e312c0d9941773b6c1b;p=openwrt%2Fstaging%2Fblogic.git

gpio: mb86s70: Return error if requesting an already assigned gpio

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---

diff --git a/drivers/gpio/gpio-mb86s7x.c b/drivers/gpio/gpio-mb86s7x.c
index 21b1ce5abdfe..ee93c0ab0a59 100644
--- a/drivers/gpio/gpio-mb86s7x.c
+++ b/drivers/gpio/gpio-mb86s7x.c
@@ -58,6 +58,11 @@ static int mb86s70_gpio_request(struct gpio_chip *gc, unsigned gpio)
 	spin_lock_irqsave(&gchip->lock, flags);
 
 	val = readl(gchip->base + PFR(gpio));
+	if (!(val & OFFSET(gpio))) {
+		spin_unlock_irqrestore(&gchip->lock, flags);
+		return -EINVAL;
+	}
+
 	val &= ~OFFSET(gpio);
 	writel(val, gchip->base + PFR(gpio));