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From: Axel Lin <axel.lin@ingics.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] gpio: Question about gpio_set_value() implementation in spear_gpio.c
Date: Wed, 19 Jun 2013 21:44:13 +0800	[thread overview]
Message-ID: <1371649453.2126.2.camel@phoenix> (raw)

Current code looks strange because no matter the value argument is 0 or 1
it always calls
	writel(1 << gpio, &regs->gpiodata[DATA_REG_ADDR(gpio)]);

And then gpio_get_value() always return 1.

I'm wondering if it needs to be fixed, something like below change:

diff --git a/drivers/gpio/spear_gpio.c b/drivers/gpio/spear_gpio.c
index d3c728e..8878608 100644
--- a/drivers/gpio/spear_gpio.c
+++ b/drivers/gpio/spear_gpio.c
@@ -52,7 +52,10 @@ int gpio_set_value(unsigned gpio, int value)
 {
 	struct gpio_regs *regs = (struct gpio_regs *)CONFIG_GPIO_BASE;
 
-	writel(1 << gpio, &regs->gpiodata[DATA_REG_ADDR(gpio)]);
+	if (value)
+		writel(1 << gpio, &regs->gpiodata[DATA_REG_ADDR(gpio)]);
+	else
+		writel(0, &regs->gpiodata[DATA_REG_ADDR(gpio)]);
 
 	return 0;
 }

             reply	other threads:[~2013-06-19 13:44 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-06-19 13:44 Axel Lin [this message]
2013-06-19 13:48 ` [U-Boot] gpio: Question about gpio_set_value() implementation in spear_gpio.c Otavio Salvador
2013-06-19 23:51   ` Marek Vasut
2013-06-19 13:49 ` Marek Vasut
2013-06-19 14:01   ` Axel Lin
2013-06-19 14:40     ` Stefan Roese
2013-06-20  3:52 ` Vipin Kumar

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