linux/arch/mips/rb532/gpio.c
Phil Sutter 2e373952cc MIPS: RB532: Provide functions for gpio configuration
As gpiolib doesn't support pin multiplexing, it provides no way to
access the GPIOFUNC register. Also there is no support for setting
interrupt status and level. These functions provide access to them and
are needed by the CompactFlash driver.

Signed-off-by: Phil Sutter <n0-1@freewrt.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-11-20 19:42:33 +00:00

273 lines
6.8 KiB
C

/*
* 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/spinlock.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <asm/mach-rc32434/rb.h>
#include <asm/mach-rc32434/gpio.h>
struct rb532_gpio_chip {
struct gpio_chip chip;
void __iomem *regbase;
};
struct mpmc_device dev3;
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,
}
};
static struct resource rb532_dev3_ctl_res[] = {
{
.name = "dev3_ctl",
.start = REGBASE + DEV3BASE,
.end = REGBASE + DEV3BASE + sizeof(struct dev_reg) - 1,
.flags = IORESOURCE_MEM,
}
};
void set_434_reg(unsigned reg_offs, unsigned bit, unsigned len, unsigned val)
{
unsigned long flags;
unsigned data;
unsigned i = 0;
spin_lock_irqsave(&dev3.lock, flags);
data = readl(IDT434_REG_BASE + reg_offs);
for (i = 0; i != len; ++i) {
if (val & (1 << i))
data |= (1 << (i + bit));
else
data &= ~(1 << (i + bit));
}
writel(data, (IDT434_REG_BASE + reg_offs));
spin_unlock_irqrestore(&dev3.lock, flags);
}
EXPORT_SYMBOL(set_434_reg);
unsigned get_434_reg(unsigned reg_offs)
{
return readl(IDT434_REG_BASE + reg_offs);
}
EXPORT_SYMBOL(get_434_reg);
void set_latch_u5(unsigned char or_mask, unsigned char nand_mask)
{
unsigned long flags;
spin_lock_irqsave(&dev3.lock, flags);
dev3.state = (dev3.state | or_mask) & ~nand_mask;
writel(dev3.state, &dev3.base);
spin_unlock_irqrestore(&dev3.lock, flags);
}
EXPORT_SYMBOL(set_latch_u5);
unsigned char get_latch_u5(void)
{
return dev3.state;
}
EXPORT_SYMBOL(get_latch_u5);
/* 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;
bitval = !!bitval; /* map parameter to {0,1} */
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 = container_of(chip, struct rb532_gpio_chip, 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 = container_of(chip, struct rb532_gpio_chip, 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 = container_of(chip, struct rb532_gpio_chip, chip);
if (rb532_get_bit(offset, gpch->regbase + GPIOFUNC))
return 1; /* alternate function, GPIOCFG is ignored */
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 = container_of(chip, struct rb532_gpio_chip, chip);
if (rb532_get_bit(offset, gpch->regbase + GPIOFUNC))
return 1; /* alternate function, GPIOCFG is ignored */
/* set the initial output value */
rb532_set_bit(value, offset, gpch->regbase + GPIOD);
rb532_set_bit(1, offset, gpch->regbase + GPIOCFG);
return 0;
}
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,
.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
*/
static void rb532_gpio_set_func(int bit, unsigned gpio)
{
rb532_set_bit(bit, gpio, rb532_gpio_chip->regbase + GPIOFUNC);
}
int __init rb532_gpio_init(void)
{
struct resource *r;
r = rb532_gpio_reg0_res;
rb532_gpio_chip->regbase = ioremap_nocache(r->start, r->end - r->start);
if (!rb532_gpio_chip->regbase) {
printk(KERN_ERR "rb532: cannot remap GPIO register 0\n");
return -ENXIO;
}
/* Register our GPIO chip */
gpiochip_add(&rb532_gpio_chip->chip);
r = rb532_dev3_ctl_res;
dev3.base = ioremap_nocache(r->start, r->end - r->start);
if (!dev3.base) {
printk(KERN_ERR "rb532: cannot remap device controller 3\n");
return -ENXIO;
}
/* configure CF_GPIO_NUM as CFRDY IRQ source */
rb532_gpio_set_func(0, CF_GPIO_NUM);
rb532_gpio_direction_input(&rb532_gpio_chip->chip, CF_GPIO_NUM);
rb532_gpio_set_ilevel(1, CF_GPIO_NUM);
rb532_gpio_set_istat(0, CF_GPIO_NUM);
return 0;
}
arch_initcall(rb532_gpio_init);