linux/arch/arm/mach-s5p6440/gpio.c
Ben Dooks 6a39954724 ARM: S5P6440: Add locking to GPIO calls
Add the new locking calls to ensure that these are always exclusively
accessing the GPIO registers.

Fixes a possible race between two threads modifying the same GPIO bank,

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-05-20 21:05:40 +09:00

343 lines
6.9 KiB
C

/* arch/arm/mach-s5p6440/gpio.c
*
* Copyright (c) 2009 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
*
* S5P6440 - GPIOlib support
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <mach/map.h>
#include <mach/gpio.h>
#include <mach/regs-gpio.h>
#include <plat/gpio-core.h>
#include <plat/gpio-cfg.h>
#include <plat/gpio-cfg-helpers.h>
/* GPIO bank summary:
*
* Bank GPIOs Style SlpCon ExtInt Group
* A 6 4Bit Yes 1
* B 7 4Bit Yes 1
* C 8 4Bit Yes 2
* F 2 2Bit Yes 4 [1]
* G 7 4Bit Yes 5
* H 10 4Bit[2] Yes 6
* I 16 2Bit Yes None
* J 12 2Bit Yes None
* N 16 2Bit No IRQ_EINT
* P 8 2Bit Yes 8
* R 15 4Bit[2] Yes 8
*
* [1] BANKF pins 14,15 do not form part of the external interrupt sources
* [2] BANK has two control registers, GPxCON0 and GPxCON1
*/
static int s5p6440_gpiolib_rbank_4bit2_input(struct gpio_chip *chip,
unsigned int offset)
{
struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
void __iomem *base = ourchip->base;
void __iomem *regcon = base;
unsigned long con;
unsigned long flags;
switch (offset) {
case 6:
offset += 1;
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
regcon -= 4;
break;
default:
offset -= 7;
break;
}
s3c_gpio_lock(ourchip, flags);
con = __raw_readl(regcon);
con &= ~(0xf << con_4bit_shift(offset));
__raw_writel(con, regcon);
s3c_gpio_unlock(ourchip, flags);
return 0;
}
static int s5p6440_gpiolib_rbank_4bit2_output(struct gpio_chip *chip,
unsigned int offset, int value)
{
struct s3c_gpio_chip *ourchip = to_s3c_gpio(chip);
void __iomem *base = ourchip->base;
void __iomem *regcon = base;
unsigned long con;
unsigned long dat;
unsigned long flags;
unsigned con_offset = offset;
switch (con_offset) {
case 6:
con_offset += 1;
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
regcon -= 4;
break;
default:
con_offset -= 7;
break;
}
s3c_gpio_lock(ourchip, flags);
con = __raw_readl(regcon);
con &= ~(0xf << con_4bit_shift(con_offset));
con |= 0x1 << con_4bit_shift(con_offset);
dat = __raw_readl(base + GPIODAT_OFF);
if (value)
dat |= 1 << offset;
else
dat &= ~(1 << offset);
__raw_writel(con, regcon);
__raw_writel(dat, base + GPIODAT_OFF);
s3c_gpio_unlock(ourchip, flags);
return 0;
}
int s5p6440_gpio_setcfg_4bit_rbank(struct s3c_gpio_chip *chip,
unsigned int off, unsigned int cfg)
{
void __iomem *reg = chip->base;
unsigned int shift;
unsigned long flags;
u32 con;
switch (off) {
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
shift = (off & 7) * 4;
reg -= 4;
break;
case 6:
shift = ((off + 1) & 7) * 4;
reg -= 4;
default:
shift = ((off + 1) & 7) * 4;
break;
}
if (s3c_gpio_is_cfg_special(cfg)) {
cfg &= 0xf;
cfg <<= shift;
}
s3c_gpio_lock(chip, flags);
con = __raw_readl(reg);
con &= ~(0xf << shift);
con |= cfg;
__raw_writel(con, reg);
s3c_gpio_unlock(chip, flags);
return 0;
}
static struct s3c_gpio_cfg s5p6440_gpio_cfgs[] = {
{
.cfg_eint = 0,
}, {
.cfg_eint = 7,
}, {
.cfg_eint = 3,
.set_config = s5p6440_gpio_setcfg_4bit_rbank,
}, {
.cfg_eint = 0,
.set_config = s3c_gpio_setcfg_s3c24xx,
.get_config = s3c_gpio_getcfg_s3c24xx,
}, {
.cfg_eint = 2,
.set_config = s3c_gpio_setcfg_s3c24xx,
.get_config = s3c_gpio_getcfg_s3c24xx,
}, {
.cfg_eint = 3,
.set_config = s3c_gpio_setcfg_s3c24xx,
.get_config = s3c_gpio_getcfg_s3c24xx,
},
};
static struct s3c_gpio_chip s5p6440_gpio_4bit[] = {
{
.base = S5P6440_GPA_BASE,
.config = &s5p6440_gpio_cfgs[1],
.chip = {
.base = S5P6440_GPA(0),
.ngpio = S5P6440_GPIO_A_NR,
.label = "GPA",
},
}, {
.base = S5P6440_GPB_BASE,
.config = &s5p6440_gpio_cfgs[1],
.chip = {
.base = S5P6440_GPB(0),
.ngpio = S5P6440_GPIO_B_NR,
.label = "GPB",
},
}, {
.base = S5P6440_GPC_BASE,
.config = &s5p6440_gpio_cfgs[1],
.chip = {
.base = S5P6440_GPC(0),
.ngpio = S5P6440_GPIO_C_NR,
.label = "GPC",
},
}, {
.base = S5P6440_GPG_BASE,
.config = &s5p6440_gpio_cfgs[1],
.chip = {
.base = S5P6440_GPG(0),
.ngpio = S5P6440_GPIO_G_NR,
.label = "GPG",
},
},
};
static struct s3c_gpio_chip s5p6440_gpio_4bit2[] = {
{
.base = S5P6440_GPH_BASE + 0x4,
.config = &s5p6440_gpio_cfgs[1],
.chip = {
.base = S5P6440_GPH(0),
.ngpio = S5P6440_GPIO_H_NR,
.label = "GPH",
},
},
};
static struct s3c_gpio_chip gpio_rbank_4bit2[] = {
{
.base = S5P6440_GPR_BASE + 0x4,
.config = &s5p6440_gpio_cfgs[2],
.chip = {
.base = S5P6440_GPR(0),
.ngpio = S5P6440_GPIO_R_NR,
.label = "GPR",
},
},
};
static struct s3c_gpio_chip s5p6440_gpio_2bit[] = {
{
.base = S5P6440_GPF_BASE,
.config = &s5p6440_gpio_cfgs[5],
.chip = {
.base = S5P6440_GPF(0),
.ngpio = S5P6440_GPIO_F_NR,
.label = "GPF",
},
}, {
.base = S5P6440_GPI_BASE,
.config = &s5p6440_gpio_cfgs[3],
.chip = {
.base = S5P6440_GPI(0),
.ngpio = S5P6440_GPIO_I_NR,
.label = "GPI",
},
}, {
.base = S5P6440_GPJ_BASE,
.config = &s5p6440_gpio_cfgs[3],
.chip = {
.base = S5P6440_GPJ(0),
.ngpio = S5P6440_GPIO_J_NR,
.label = "GPJ",
},
}, {
.base = S5P6440_GPN_BASE,
.config = &s5p6440_gpio_cfgs[4],
.chip = {
.base = S5P6440_GPN(0),
.ngpio = S5P6440_GPIO_N_NR,
.label = "GPN",
},
}, {
.base = S5P6440_GPP_BASE,
.config = &s5p6440_gpio_cfgs[5],
.chip = {
.base = S5P6440_GPP(0),
.ngpio = S5P6440_GPIO_P_NR,
.label = "GPP",
},
},
};
void __init s5p6440_gpiolib_set_cfg(struct s3c_gpio_cfg *chipcfg, int nr_chips)
{
for (; nr_chips > 0; nr_chips--, chipcfg++) {
if (!chipcfg->set_config)
chipcfg->set_config = s3c_gpio_setcfg_s3c64xx_4bit;
if (!chipcfg->get_config)
chipcfg->get_config = s3c_gpio_getcfg_s3c64xx_4bit;
if (!chipcfg->set_pull)
chipcfg->set_pull = s3c_gpio_setpull_updown;
if (!chipcfg->get_pull)
chipcfg->get_pull = s3c_gpio_getpull_updown;
}
}
static void __init s5p6440_gpio_add_rbank_4bit2(struct s3c_gpio_chip *chip,
int nr_chips)
{
for (; nr_chips > 0; nr_chips--, chip++) {
chip->chip.direction_input = s5p6440_gpiolib_rbank_4bit2_input;
chip->chip.direction_output =
s5p6440_gpiolib_rbank_4bit2_output;
s3c_gpiolib_add(chip);
}
}
static int __init s5p6440_gpiolib_init(void)
{
struct s3c_gpio_chip *chips = s5p6440_gpio_2bit;
int nr_chips = ARRAY_SIZE(s5p6440_gpio_2bit);
s5p6440_gpiolib_set_cfg(s5p6440_gpio_cfgs,
ARRAY_SIZE(s5p6440_gpio_cfgs));
for (; nr_chips > 0; nr_chips--, chips++)
s3c_gpiolib_add(chips);
samsung_gpiolib_add_4bit_chips(s5p6440_gpio_4bit,
ARRAY_SIZE(s5p6440_gpio_4bit));
samsung_gpiolib_add_4bit2_chips(s5p6440_gpio_4bit2,
ARRAY_SIZE(s5p6440_gpio_4bit2));
s5p6440_gpio_add_rbank_4bit2(gpio_rbank_4bit2,
ARRAY_SIZE(gpio_rbank_4bit2));
return 0;
}
arch_initcall(s5p6440_gpiolib_init);