/*
* Miscellaneous functions for IDT EB434 board
*
* Copyright 2004 IDT Inc. (rischelp@idt.com)
* Copyright 2006 Phil Sutter <n0-1@freewrt.org>
* Copyright 2007 Florian Fainelli <florian@openwrt.org>
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/export.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/gpio/driver.h>
#include <asm/mach-rc32434/rb.h>
#include <asm/mach-rc32434/gpio.h>
struct rb532_gpio_chip {
struct gpio_chip chip;
void __iomem *regbase;
};
static struct resource rb532_gpio_reg0_res[] = {
{
.name = "gpio_reg0",
.start = REGBASE + GPIOBASE,
.end = REGBASE + GPIOBASE + sizeof(struct rb532_gpio_reg) - 1,
.flags = IORESOURCE_MEM,
}
};
/* rb532_set_bit - sanely set a bit
*
* bitval: new value for the bit
* offset: bit index in the 4 byte address range
* ioaddr: 4 byte aligned address being altered
*/
static inline void rb532_set_bit(unsigned bitval,
unsigned offset, void __iomem *ioaddr)
{
unsigned long flags;
u32 val;
local_irq_save(flags);
val = readl(ioaddr);
val &= ~(!bitval << offset); /* unset bit if bitval == 0 */
val |= (!!bitval << offset); /* set bit if bitval == 1 */
writel(val, ioaddr);
local_irq_restore(flags);
}
/* rb532_get_bit - read a bit
*
* returns the boolean state of the bit, which may be > 1
*/
static inline int rb532_get_bit(unsigned offset, void __iomem *ioaddr)
{
return readl(ioaddr) & (1 << offset);
}
/*
* Return GPIO level */
static int rb532_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct rb532_gpio_chip *gpch;
gpch = gpiochip_get_data(chip);
return !!rb532_get_bit(offset, gpch->regbase + GPIOD);
}
/*
* Set output GPIO level
*/
static void rb532_gpio_set(struct gpio_chip *chip,
unsigned offset, int value)
{
struct rb532_gpio_chip *gpch;
gpch = gpiochip_get_data(chip);
rb532_set_bit(value, offset, gpch->regbase + GPIOD);
}
/*
* Set GPIO direction to input
*/
static int rb532_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
struct rb532_gpio_chip *gpch;
gpch = gpiochip_get_data(chip);
/* disable alternate function in case it's set */
rb532_set_bit(0, offset, gpch->regbase + GPIOFUNC);
rb532_set_bit(0, offset, gpch->regbase + GPIOCFG);
return 0;
}
/*
* Set GPIO direction to output
*/
static int rb532_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
struct rb532_gpio_chip *gpch;
gpch = gpiochip_get_data(chip);
/* disable alternate function in case it's set */
rb532_set_bit(0, offset, gpch->regbase + GPIOFUNC);
/* set the initial output value */
rb532_set_bit(value, offset, gpch->regbase + GPIOD);
rb532_set_bit(1, offset, gpch->regbase + GPIOCFG);
return 0;
}
static int rb532_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
{
return 8 + 4 * 32 + gpio;
}
static struct rb532_gpio_chip rb532_gpio_chip[] = {
[0] = {
.chip = {
.label = "gpio0",
.direction_input = rb532_gpio_direction_input,
.direction_output = rb532_gpio_direction_output,
.get = rb532_gpio_get,
.set = rb532_gpio_set,
.to_irq = rb532_gpio_to_irq,
.base = 0,
.ngpio = 32,
},
},
};
/*
* Set GPIO interrupt level
*/
void rb532_gpio_set_ilevel(int bit, unsigned gpio)
{
rb532_set_bit(bit, gpio, rb532_gpio_chip->regbase + GPIOILEVEL);
}
EXPORT_SYMBOL(rb532_gpio_set_ilevel);
/*
* Set GPIO interrupt status
*/
void rb532_gpio_set_istat(int bit, unsigned gpio)
{
rb532_set_bit(bit, gpio, rb532_gpio_chip->regbase + GPIOISTAT);
}
EXPORT_SYMBOL(rb532_gpio_set_istat);
/*
* Configure GPIO alternate function
*/
void rb532_gpio_set_func(unsigned gpio)
{
rb532_set_bit(1, gpio, rb532_gpio_chip->regbase + GPIOFUNC);
}
EXPORT_SYMBOL(rb532_gpio_set_func);
int __init rb532_gpio_init(void)
{
struct resource *r;
r = rb532_gpio_reg0_res;
rb532_gpio_chip->regbase = ioremap_nocache(r->start, resource_size(r));
if (!rb532_gpio_chip->regbase) {
printk(KERN_ERR "rb532: cannot remap GPIO register 0\n");
return -ENXIO;
}
/* Register our GPIO chip */
gpiochip_add_data(&rb532_gpio_chip->chip, rb532_gpio_chip);
return 0;
}
arch_initcall(rb532_gpio_init);
