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>

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)
 {
@@ -65,6 +79,32 @@ static void __nmk_gpio_set_pull(struct nmk_gpio_chip *nmk_chip,
 		writel(bit, nmk_chip->addr + NMK_GPIO_DATC);
 }
 
+/**
+ * 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

arch/arm/plat-nomadik/include/plat/gpio.h

@@ -62,6 +62,13 @@ enum nmk_gpio_pull {
 	NMK_GPIO_PULL_DOWN,
 };
 
+/* Sleep mode */
+enum nmk_gpio_slpm {
+	NMK_GPIO_SLPM_INPUT,
+	NMK_GPIO_SLPM_NOCHANGE,
+};
+
+extern int nmk_gpio_set_slpm(int gpio, enum nmk_gpio_slpm mode);
 extern int nmk_gpio_set_pull(int gpio, enum nmk_gpio_pull pull);
 extern int nmk_gpio_set_mode(int gpio, int gpio_mode);
 extern int nmk_gpio_get_mode(int gpio);