ARM: 6149/1: nomadik-gpio: add function to configure sleep mode behaviour

Cc: Alessandro Rubini <rubini@unipv.it>

Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 40 insertions, 0 deletions

diff --git a/arch/arm/plat-nomadik/gpio.c b/arch/arm/plat-nomadik/gpio.c
index 50c49fa9e01a..a678e887e0fe 100644
--- a/arch/arm/plat-nomadik/gpio.c
+++ b/arch/arm/plat-nomadik/gpio.c
@@ -46,6 +46,20 @@ struct nmk_gpio_chip {
         u32 edge_falling;
 };
 
+static void __nmk_gpio_set_slpm(struct nmk_gpio_chip *nmk_chip,
+                                unsigned offset, enum nmk_gpio_slpm mode)
+{
+        u32 bit = 1 << offset;
+        u32 slpm;
+
+        slpm = readl(nmk_chip->addr + NMK_GPIO_SLPC);
+        if (mode == NMK_GPIO_SLPM_NOCHANGE)
+                slpm |= bit;
+        else
+                slpm &= ~bit;
+        writel(slpm, nmk_chip->addr + NMK_GPIO_SLPC);
+}
+
 static void __nmk_gpio_set_pull(struct nmk_gpio_chip *nmk_chip,
                                 unsigned offset, enum nmk_gpio_pull pull)
 {
@@ -66,6 +80,32 @@ static void __nmk_gpio_set_pull(struct nmk_gpio_chip *nmk_chip,
 }
 
 /**
+ * nmk_gpio_set_slpm() - configure the sleep mode of a pin
+ * @gpio: pin number
+ * @mode: NMK_GPIO_SLPM_INPUT or NMK_GPIO_SLPM_NOCHANGE,
+ *
+ * Sets the sleep mode of a pin.  If @mode is NMK_GPIO_SLPM_INPUT, the pin is
+ * changed to an input (with pullup/down enabled) in sleep and deep sleep.  If
+ * @mode is NMK_GPIO_SLPM_NOCHANGE, the pin remains in the state it was
+ * configured even when in sleep and deep sleep.
+ */
+int nmk_gpio_set_slpm(int gpio, enum nmk_gpio_slpm mode)
+{
+        struct nmk_gpio_chip *nmk_chip;
+        unsigned long flags;
+
+        nmk_chip = get_irq_chip_data(NOMADIK_GPIO_TO_IRQ(gpio));
+        if (!nmk_chip)
+                return -EINVAL;
+
+        spin_lock_irqsave(&nmk_chip->lock, flags);
+        __nmk_gpio_set_slpm(nmk_chip, gpio - nmk_chip->chip.base, mode);
+        spin_unlock_irqrestore(&nmk_chip->lock, flags);
+
+        return 0;
+}
+
+/**
  * nmk_gpio_set_pull() - enable/disable pull up/down on a gpio
  * @gpio: pin number
  * @pull: one of NMK_GPIO_PULL_DOWN, NMK_GPIO_PULL_UP, and NMK_GPIO_PULL_NONE