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plat-nomadik: pull-up/down settings for GPIO resume

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Suspend/resume didn't take care of pull-up and pull-down
settings and writing back the DAT register at resume can
change pull up/down settings, depending on pin input value.
Output values are now also restored.

Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Jonas Aaberg 2010-10-13 13:14:17 +02:00 committed by Linus Walleij
parent 33b744b351
commit 9c66ee6f55
2 changed files with 60 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
arch/arm/plat-nomadik/Kconfig
View File

@ -25,4 +25,10 @@ config NOMADIK_GPIO
help
Support for the Nomadik GPIO controller.
config NOMADIK_GPIO_PM
bool
depends on NOMADIK_GPIO && PM
help
Support PM for the Nomadik GPIO controller.
endif

78
arch/arm/plat-nomadik/gpio.c
View File

@ -30,11 +30,23 @@
/*
* The GPIO module in the Nomadik family of Systems-on-Chip is an
* AMBA device, managing 32 pins and alternate functions. The logic block
* is currently only used in the Nomadik.
* is currently used in the Nomadik and ux500.
*
* Symbols in this file are called "nmk_gpio" for "nomadik gpio"
*/
static const u32 backup_regs[] = {
NMK_GPIO_PDIS,
NMK_GPIO_DIR,
NMK_GPIO_AFSLA,
NMK_GPIO_AFSLB,
NMK_GPIO_SLPC,
NMK_GPIO_RIMSC,
NMK_GPIO_FIMSC,
NMK_GPIO_RWIMSC,
NMK_GPIO_FWIMSC,
};
struct nmk_gpio_chip {
struct gpio_chip chip;
void __iomem *addr;
@ -47,7 +59,9 @@ struct nmk_gpio_chip {
/* Keep track of configured edges */
u32 edge_rising;
u32 edge_falling;
u32 backup[10];
u32 backup[ARRAY_SIZE(backup_regs)];
/* Bitmap, 1 = pull up, 0 = pull down */
u32 pull;
};
static void __nmk_gpio_set_mode(struct nmk_gpio_chip *nmk_chip,
@ -93,10 +107,13 @@ static void __nmk_gpio_set_pull(struct nmk_gpio_chip *nmk_chip,
pdis &= ~bit;
writel(pdis, nmk_chip->addr + NMK_GPIO_PDIS);
if (pull == NMK_GPIO_PULL_UP)
if (pull == NMK_GPIO_PULL_UP) {
nmk_chip->pull |= bit;
writel(bit, nmk_chip->addr + NMK_GPIO_DATS);
else if (pull == NMK_GPIO_PULL_DOWN)
} else if (pull == NMK_GPIO_PULL_DOWN) {
nmk_chip->pull &= ~bit;
writel(bit, nmk_chip->addr + NMK_GPIO_DATC);
}
}
static void __nmk_gpio_make_input(struct nmk_gpio_chip *nmk_chip,
@ -317,6 +334,15 @@ int nmk_gpio_set_pull(int gpio, enum nmk_gpio_pull pull)
}
/* Mode functions */
/**
* nmk_gpio_set_mode() - set the mux mode of a gpio pin
* @gpio: pin number
* @gpio_mode: one of NMK_GPIO_ALT_GPIO, NMK_GPIO_ALT_A,
* NMK_GPIO_ALT_B, and NMK_GPIO_ALT_C
*
* Sets the mode of the specified pin to one of the alternate functions or
* plain GPIO.
*/
int nmk_gpio_set_mode(int gpio, int gpio_mode)
{
struct nmk_gpio_chip *nmk_chip;
@ -832,35 +858,39 @@ out:
return ret;
}
#ifdef CONFIG_PM
#ifdef CONFIG_NOMADIK_GPIO_PM
static int nmk_gpio_pm(struct platform_device *dev, bool suspend)
{
struct nmk_gpio_chip *nmk_chip = platform_get_drvdata(dev);
int i;
static const unsigned int regs[] = {
NMK_GPIO_DAT,
NMK_GPIO_PDIS,
NMK_GPIO_DIR,
NMK_GPIO_AFSLA,
NMK_GPIO_AFSLB,
NMK_GPIO_SLPC,
NMK_GPIO_RIMSC,
NMK_GPIO_FIMSC,
NMK_GPIO_RWIMSC,
NMK_GPIO_FWIMSC,
};
u32 dir;
u32 dat;
BUILD_BUG_ON(ARRAY_SIZE(nmk_chip->backup) != ARRAY_SIZE(regs));
/* XXX: is this sufficient? what about pull-up/down configuration? */
for (i = 0; i < ARRAY_SIZE(regs); i++) {
for (i = 0; i < ARRAY_SIZE(backup_regs); i++) {
if (suspend)
nmk_chip->backup[i] = readl(nmk_chip->addr + regs[i]);
nmk_chip->backup[i] = readl(nmk_chip->addr +
backup_regs[i]);
else
writel(nmk_chip->backup[i], nmk_chip->addr + regs[i]);
writel(nmk_chip->backup[i],
nmk_chip->addr + backup_regs[i]);
}
if (!suspend) {
/*
* Restore pull-up and pull-down on inputs and
* outputs.
*/
dir = readl(nmk_chip->addr + NMK_GPIO_DIR);
dat = readl(nmk_chip->addr + NMK_GPIO_DAT);
writel((nmk_chip->pull & ~dir) |
(dat & dir),
nmk_chip->addr + NMK_GPIO_DATS);
writel((~nmk_chip->pull & ~dir) |
(~dat & dir),
nmk_chip->addr + NMK_GPIO_DATC);
}
return 0;
}