[ARM] pxa: allow dynamic enable/disable of GPIO wakeup for pxa{25x,27x}

Changes include:

1. rename MFP_LPM_WAKEUP_ENABLE into MFP_LPM_CAN_WAKEUP to indicate
   the board capability of this pin to wakeup the system

2. add gpio_set_wake() and keypad_set_wake() to allow dynamically
   enable/disable wakeup from GPIOs and keypad GPIO

   * these functions are currently kept in mfp-pxa2xx.c due to their
     dependency to the MFP configuration

3. pxa2xx_mfp_config() only gives early warning if MFP_LPM_CAN_WAKEUP
   is set on incorrect pins

So that the GPIO's wakeup capability is now decided by the following:

   a) processor's capability: (only those GPIOs which have dedicated
      bits within PWER/PRER/PFER can wakeup the system), this is
      initialized by pxa{25x,27x}_init_mfp()

   b) board design decides:
      - whether the pin is designed to wakeup the system (some of
        the GPIOs are configured as other functions, which is not
        intended to be a wakeup source), by OR'ing the pin config
        with MFP_LPM_CAN_WAKEUP

      - which edge the pin is designed to wakeup the system, this
        may depends on external peripherals/connections, which is
        totally board specific; this is indicated by MFP_LPM_EDGE_*

   c) the corresponding device's (most likely the gpio_keys.c) wakeup
      attribute:

Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 74 insertions, 19 deletions

diff --git a/arch/arm/mach-pxa/mfp-pxa2xx.c b/arch/arm/mach-pxa/mfp-pxa2xx.c
index f85f681c0393..22097a1707cc 100644
--- a/arch/arm/mach-pxa/mfp-pxa2xx.c
+++ b/arch/arm/mach-pxa/mfp-pxa2xx.c
@@ -28,15 +28,17 @@
 
 #define PWER_WE35       (1 << 24)
 
-static struct {
+struct gpio_desc {
         unsigned        valid           : 1;
         unsigned        can_wakeup      : 1;
         unsigned        keypad_gpio     : 1;
         unsigned int    mask; /* bit mask in PWER or PKWR */
         unsigned long   config;
-} gpio_desc[MFP_PIN_GPIO127 + 1];
+};
+
+static struct gpio_desc gpio_desc[MFP_PIN_GPIO127 + 1];
 
-static inline int __mfp_config_gpio(unsigned gpio, unsigned long c)
+static int __mfp_config_gpio(unsigned gpio, unsigned long c)
 {
         unsigned long gafr, mask = GPIO_bit(gpio);
         int fn;
@@ -70,26 +72,19 @@ static inline int __mfp_config_gpio(unsigned gpio, unsigned long c)
                 return -EINVAL;
         }
 
-        /* wakeup enabling */
-        if ((c & MFP_LPM_WAKEUP_ENABLE) == 0)
-                return 0;
-
-        if (!gpio_desc[gpio].can_wakeup || c & MFP_DIR_OUT) {
+        /* give early warning if MFP_LPM_CAN_WAKEUP is set on the
+         * configurations of those pins not able to wakeup
+         */
+        if ((c & MFP_LPM_CAN_WAKEUP) && !gpio_desc[gpio].can_wakeup) {
                 pr_warning("%s: GPIO%d unable to wakeup\n",
                                 __func__, gpio);
                 return -EINVAL;
         }
 
-        if (gpio_desc[gpio].keypad_gpio)
-                PKWR |= gpio_desc[gpio].mask;
-        else {
-                PWER |= gpio_desc[gpio].mask;
-
-                if (c & MFP_LPM_EDGE_RISE)
-                        PRER |= gpio_desc[gpio].mask;
-
-                if (c & MFP_LPM_EDGE_FALL)
-                        PFER |= gpio_desc[gpio].mask;
+        if ((c & MFP_LPM_CAN_WAKEUP) && (c & MFP_DIR_OUT)) {
+                pr_warning("%s: output GPIO%d unable to wakeup\n",
+                                __func__, gpio);
+                return -EINVAL;
         }
 
         return 0;
@@ -120,6 +115,45 @@ void pxa2xx_mfp_config(unsigned long *mfp_cfgs, int num)
         }
 }
 
+int gpio_set_wake(unsigned int gpio, unsigned int on)
+{
+        struct gpio_desc *d;
+        unsigned long c;
+
+        if (gpio > mfp_to_gpio(MFP_PIN_GPIO127))
+                return -EINVAL;
+
+        d = &gpio_desc[gpio];
+        c = d->config;
+
+        if (!d->valid)
+                return -EINVAL;
+
+        if (d->keypad_gpio)
+                return -EINVAL;
+
+        if (d->can_wakeup && (c & MFP_LPM_CAN_WAKEUP)) {
+                if (on) {
+                        PWER |= d->mask;
+
+                        if (c & MFP_LPM_EDGE_RISE)
+                                PRER |= d->mask;
+                        else
+                                PRER &= ~d->mask;
+
+                        if (c & MFP_LPM_EDGE_FALL)
+                                PFER |= d->mask;
+                        else
+                                PFER &= ~d->mask;
+                } else {
+                        PWER &= ~d->mask;
+                        PRER &= ~d->mask;
+                        PFER &= ~d->mask;
+                }
+        }
+        return 0;
+}
+
 #ifdef CONFIG_PXA25x
 static int __init pxa25x_mfp_init(void)
 {
@@ -141,11 +175,32 @@ postcore_initcall(pxa25x_mfp_init);
 #endif /* CONFIG_PXA25x */
 
 #ifdef CONFIG_PXA27x
-static int pxa27x_pkwr_gpio[] __initdata = {
+static int pxa27x_pkwr_gpio[] = {
         13, 16, 17, 34, 36, 37, 38, 39, 90, 91, 93, 94,
         95, 96, 97, 98, 99, 100, 101, 102
 };
 
+int keypad_set_wake(unsigned int on)
+{
+        unsigned int i, gpio, mask = 0;
+
+        if (!on) {
+                PKWR = 0;
+                return 0;
+        }
+
+        for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
+
+                gpio = pxa27x_pkwr_gpio[i];
+
+                if (gpio_desc[gpio].config & MFP_LPM_CAN_WAKEUP)
+                        mask |= gpio_desc[gpio].mask;
+        }
+
+        PKWR = mask;
+        return 0;
+}
+
 static int __init pxa27x_mfp_init(void)
 {
         int i, gpio;