linux/arch/arm/mach-vt8500/gpio.c
Alexey Charkov 21f47fbc5b ARM: 6597/1: Add basic architecture support for VIA/WonderMedia 85xx SoC's
This adds support for the family of Systems-on-Chip produced initially
by VIA and now its subsidiary WonderMedia that have recently become
widespread in lower-end Chinese ARM-based tablets and netbooks.

Support is included for both VT8500 and WM8505, selectable by a
configuration switch at kernel build time.

Included are basic machine initialization files, register and
interrupt definitions, support for the on-chip interrupt controller,
high-precision OS timer, GPIO lines, necessary macros for early debug,
pulse-width-modulated outputs control, as well as platform device
configurations for the specific drivers implemented elsewhere.

Signed-off-by: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-01-25 15:07:01 +00:00

241 lines
6.3 KiB
C

/* linux/arch/arm/mach-vt8500/gpio.c
*
* Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <linux/gpio.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/io.h>
#include "devices.h"
#define to_vt8500(__chip) container_of(__chip, struct vt8500_gpio_chip, chip)
#define ENABLE_REGS 0x0
#define DIRECTION_REGS 0x20
#define OUTVALUE_REGS 0x40
#define INVALUE_REGS 0x60
#define EXT_REGOFF 0x1c
static void __iomem *regbase;
struct vt8500_gpio_chip {
struct gpio_chip chip;
unsigned int shift;
unsigned int regoff;
};
static int gpio_to_irq_map[8];
static int vt8500_muxed_gpio_request(struct gpio_chip *chip,
unsigned offset)
{
struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
unsigned val = readl(regbase + ENABLE_REGS + vt8500_chip->regoff);
val |= (1 << vt8500_chip->shift << offset);
writel(val, regbase + ENABLE_REGS + vt8500_chip->regoff);
return 0;
}
static void vt8500_muxed_gpio_free(struct gpio_chip *chip,
unsigned offset)
{
struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
unsigned val = readl(regbase + ENABLE_REGS + vt8500_chip->regoff);
val &= ~(1 << vt8500_chip->shift << offset);
writel(val, regbase + ENABLE_REGS + vt8500_chip->regoff);
}
static int vt8500_muxed_gpio_direction_input(struct gpio_chip *chip,
unsigned offset)
{
struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
unsigned val = readl(regbase + DIRECTION_REGS + vt8500_chip->regoff);
val &= ~(1 << vt8500_chip->shift << offset);
writel(val, regbase + DIRECTION_REGS + vt8500_chip->regoff);
return 0;
}
static int vt8500_muxed_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
unsigned val = readl(regbase + DIRECTION_REGS + vt8500_chip->regoff);
val |= (1 << vt8500_chip->shift << offset);
writel(val, regbase + DIRECTION_REGS + vt8500_chip->regoff);
if (value) {
val = readl(regbase + OUTVALUE_REGS + vt8500_chip->regoff);
val |= (1 << vt8500_chip->shift << offset);
writel(val, regbase + OUTVALUE_REGS + vt8500_chip->regoff);
}
return 0;
}
static int vt8500_muxed_gpio_get_value(struct gpio_chip *chip,
unsigned offset)
{
struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
return (readl(regbase + INVALUE_REGS + vt8500_chip->regoff)
>> vt8500_chip->shift >> offset) & 1;
}
static void vt8500_muxed_gpio_set_value(struct gpio_chip *chip,
unsigned offset, int value)
{
struct vt8500_gpio_chip *vt8500_chip = to_vt8500(chip);
unsigned val = readl(regbase + INVALUE_REGS + vt8500_chip->regoff);
if (value)
val |= (1 << vt8500_chip->shift << offset);
else
val &= ~(1 << vt8500_chip->shift << offset);
writel(val, regbase + INVALUE_REGS + vt8500_chip->regoff);
}
#define VT8500_GPIO_BANK(__name, __shift, __off, __base, __num) \
{ \
.chip = { \
.label = __name, \
.request = vt8500_muxed_gpio_request, \
.free = vt8500_muxed_gpio_free, \
.direction_input = vt8500_muxed_gpio_direction_input, \
.direction_output = vt8500_muxed_gpio_direction_output, \
.get = vt8500_muxed_gpio_get_value, \
.set = vt8500_muxed_gpio_set_value, \
.can_sleep = 0, \
.base = __base, \
.ngpio = __num, \
}, \
.shift = __shift, \
.regoff = __off, \
}
static struct vt8500_gpio_chip vt8500_muxed_gpios[] = {
VT8500_GPIO_BANK("uart0", 0, 0x0, 8, 4),
VT8500_GPIO_BANK("uart1", 4, 0x0, 12, 4),
VT8500_GPIO_BANK("spi0", 8, 0x0, 16, 4),
VT8500_GPIO_BANK("spi1", 12, 0x0, 20, 4),
VT8500_GPIO_BANK("spi2", 16, 0x0, 24, 4),
VT8500_GPIO_BANK("pwmout", 24, 0x0, 28, 2),
VT8500_GPIO_BANK("sdmmc", 0, 0x4, 30, 11),
VT8500_GPIO_BANK("ms", 16, 0x4, 41, 7),
VT8500_GPIO_BANK("i2c0", 24, 0x4, 48, 2),
VT8500_GPIO_BANK("i2c1", 26, 0x4, 50, 2),
VT8500_GPIO_BANK("mii", 0, 0x8, 52, 20),
VT8500_GPIO_BANK("see", 20, 0x8, 72, 4),
VT8500_GPIO_BANK("ide", 24, 0x8, 76, 7),
VT8500_GPIO_BANK("ccir", 0, 0xc, 83, 19),
VT8500_GPIO_BANK("ts", 8, 0x10, 102, 11),
VT8500_GPIO_BANK("lcd", 0, 0x14, 113, 23),
};
static int vt8500_gpio_direction_input(struct gpio_chip *chip,
unsigned offset)
{
unsigned val = readl(regbase + DIRECTION_REGS + EXT_REGOFF);
val &= ~(1 << offset);
writel(val, regbase + DIRECTION_REGS + EXT_REGOFF);
return 0;
}
static int vt8500_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
unsigned val = readl(regbase + DIRECTION_REGS + EXT_REGOFF);
val |= (1 << offset);
writel(val, regbase + DIRECTION_REGS + EXT_REGOFF);
if (value) {
val = readl(regbase + OUTVALUE_REGS + EXT_REGOFF);
val |= (1 << offset);
writel(val, regbase + OUTVALUE_REGS + EXT_REGOFF);
}
return 0;
}
static int vt8500_gpio_get_value(struct gpio_chip *chip,
unsigned offset)
{
return (readl(regbase + INVALUE_REGS + EXT_REGOFF) >> offset) & 1;
}
static void vt8500_gpio_set_value(struct gpio_chip *chip,
unsigned offset, int value)
{
unsigned val = readl(regbase + OUTVALUE_REGS + EXT_REGOFF);
if (value)
val |= (1 << offset);
else
val &= ~(1 << offset);
writel(val, regbase + OUTVALUE_REGS + EXT_REGOFF);
}
static int vt8500_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
if (offset > 7)
return -EINVAL;
return gpio_to_irq_map[offset];
}
static struct gpio_chip vt8500_external_gpios = {
.label = "extgpio",
.direction_input = vt8500_gpio_direction_input,
.direction_output = vt8500_gpio_direction_output,
.get = vt8500_gpio_get_value,
.set = vt8500_gpio_set_value,
.to_irq = vt8500_gpio_to_irq,
.can_sleep = 0,
.base = 0,
.ngpio = 8,
};
void __init vt8500_gpio_init(void)
{
int i;
for (i = 0; i < 8; i++)
gpio_to_irq_map[i] = wmt_gpio_ext_irq[i];
regbase = ioremap(wmt_gpio_base, SZ_64K);
if (!regbase) {
printk(KERN_ERR "Failed to map MMIO registers for GPIO\n");
return;
}
gpiochip_add(&vt8500_external_gpios);
for (i = 0; i < ARRAY_SIZE(vt8500_muxed_gpios); i++)
gpiochip_add(&vt8500_muxed_gpios[i].chip);
}