gpio.c

linux 内核源代码

/*
 *  Copyright (C) 2007, OpenWrt.org, Florian Fainelli <[e-mail]>
 *  	Architecture specific GPIO support
 *
 *  This program is free software; you can redistribute	 it and/or modify it
 *  under  the terms of	 the GNU General  Public License as published by the
 *  Free Software Foundation;  either version 2 of the	License, or (at your
 *  option) any later version.
 *
 *  THIS  SOFTWARE  IS PROVIDED	  ``AS	IS'' AND   ANY	EXPRESS OR IMPLIED
 *  WARRANTIES,	  INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
 *  NO	EVENT  SHALL   THE AUTHOR  BE	 LIABLE FOR ANY	  DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *  NOT LIMITED	  TO, PROCUREMENT OF  SUBSTITUTE GOODS	OR SERVICES; LOSS OF
 *  USE, DATA,	OR PROFITS; OR	BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 *  ANY THEORY OF LIABILITY, WHETHER IN	 CONTRACT, STRICT LIABILITY, OR TORT
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *  You should have received a copy of the  GNU General Public License along
 *  with this program; if not, write  to the Free Software Foundation, Inc.,
 *  675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *  Notes :
 * 	au1000 SoC have only one GPIO line : GPIO1
 * 	others have a second one : GPIO2
 */

#include <linux/autoconf.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/types.h>
#include <linux/module.h>

#include <asm/addrspace.h>

#include <asm/mach-au1x00/au1000.h>
#include <asm/gpio.h>

#define gpio1 sys
#if !defined(CONFIG_SOC_AU1000)

static struct au1x00_gpio2 *const gpio2 = (struct au1x00_gpio2 *) GPIO2_BASE;
#define GPIO2_OUTPUT_ENABLE_MASK 	0x00010000

static int au1xxx_gpio2_read(unsigned gpio)
{
	gpio -= AU1XXX_GPIO_BASE;
	return ((gpio2->pinstate >> gpio) & 0x01);
}

static void au1xxx_gpio2_write(unsigned gpio, int value)
{
	gpio -= AU1XXX_GPIO_BASE;

	gpio2->output = (GPIO2_OUTPUT_ENABLE_MASK << gpio) | (value << gpio);
}

static int au1xxx_gpio2_direction_input(unsigned gpio)
{
	gpio -= AU1XXX_GPIO_BASE;
	gpio2->dir &= ~(0x01 << gpio);
	return 0;
}

static int au1xxx_gpio2_direction_output(unsigned gpio, int value)
{
	gpio -= AU1XXX_GPIO_BASE;
	gpio2->dir = (0x01 << gpio) | (value << gpio);
	return 0;
}

#endif /* !defined(CONFIG_SOC_AU1000) */

static int au1xxx_gpio1_read(unsigned gpio)
{
	return ((gpio1->pinstaterd >> gpio) & 0x01);
}

static void au1xxx_gpio1_write(unsigned gpio, int value)
{
	if (value)
		gpio1->outputset = (0x01 << gpio);
	else
		/* Output a zero */
		gpio1->outputclr = (0x01 << gpio);
}

static int au1xxx_gpio1_direction_input(unsigned gpio)
{
	gpio1->pininputen = (0x01 << gpio);
	return 0;
}

static int au1xxx_gpio1_direction_output(unsigned gpio, int value)
{
	gpio1->trioutclr = (0x01 & gpio);
	return 0;
}

int au1xxx_gpio_get_value(unsigned gpio)
{
	if (gpio >= AU1XXX_GPIO_BASE)
#if defined(CONFIG_SOC_AU1000)
		return 0;
#else
		return au1xxx_gpio2_read(gpio);
#endif
	else
		return au1xxx_gpio1_read(gpio);
}

EXPORT_SYMBOL(au1xxx_gpio_get_value);

void au1xxx_gpio_set_value(unsigned gpio, int value)
{
	if (gpio >= AU1XXX_GPIO_BASE)
#if defined(CONFIG_SOC_AU1000)
		;
#else
		au1xxx_gpio2_write(gpio, value);
#endif
	else
		au1xxx_gpio1_write(gpio, value);
}

EXPORT_SYMBOL(au1xxx_gpio_set_value);

int au1xxx_gpio_direction_input(unsigned gpio)
{
	if (gpio >= AU1XXX_GPIO_BASE)
#if defined(CONFIG_SOC_AU1000)
		return -ENODEV;
#else
		return au1xxx_gpio2_direction_input(gpio);
#endif

	return au1xxx_gpio1_direction_input(gpio);
}

EXPORT_SYMBOL(au1xxx_gpio_direction_input);

int au1xxx_gpio_direction_output(unsigned gpio, int value)
{
	if (gpio >= AU1XXX_GPIO_BASE)
#if defined(CONFIG_SOC_AU1000)
		return -ENODEV;
#else
		return au1xxx_gpio2_direction_output(gpio, value);
#endif

	return au1xxx_gpio1_direction_output(gpio, value);
}

EXPORT_SYMBOL(au1xxx_gpio_direction_output);