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authorJonas Aaberg <jonas.aberg@stericsson.com>2010-10-13 13:14:17 +0200
committerLinus Walleij <linus.walleij@linaro.org>2011-03-14 14:05:15 +0100
commit9c66ee6f55667c5f7e118135d3175b0100e160b9 (patch)
tree2324b4b8ac963526c266e4883be07d15e85ffd3e /arch/arm/plat-nomadik/gpio.c
parent33b744b35189baaa260f526cf117392095331843 (diff)
plat-nomadik: pull-up/down settings for GPIO resume
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>
Diffstat (limited to 'arch/arm/plat-nomadik/gpio.c')
-rw-r--r--arch/arm/plat-nomadik/gpio.c78
1 files changed, 54 insertions, 24 deletions
diff --git a/arch/arm/plat-nomadik/gpio.c b/arch/arm/plat-nomadik/gpio.c
index 971e5d3798e4..71682a87a878 100644
--- a/arch/arm/plat-nomadik/gpio.c
+++ b/arch/arm/plat-nomadik/gpio.c
@@ -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;
}