[ARM] pxa: add pxa2xx_mfp_set_lpm() to facilitate low power state change

Some boards want to change low power state of pins on-the-fly, this
function helps to facilitate that operation instead of switching
back-n-forth between two configurations with pxa2xx_mfp_config().

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

2 files changed, 38 insertions, 14 deletions

diff --git a/arch/arm/mach-pxa/mfp-pxa2xx.c b/arch/arm/mach-pxa/mfp-pxa2xx.c
index ed91c043471b..fd4545eab803 100644
--- a/arch/arm/mach-pxa/mfp-pxa2xx.c
+++ b/arch/arm/mach-pxa/mfp-pxa2xx.c
@@ -39,6 +39,28 @@ struct gpio_desc {
 
 static struct gpio_desc gpio_desc[MFP_PIN_GPIO127 + 1];
 
+static int __mfp_config_lpm(unsigned gpio, unsigned long lpm)
+{
+        unsigned mask = GPIO_bit(gpio);
+
+        /* low power state */
+        switch (lpm) {
+        case MFP_LPM_DRIVE_HIGH:
+                PGSR(gpio) |= mask;
+                break;
+        case MFP_LPM_DRIVE_LOW:
+                PGSR(gpio) &= ~mask;
+                break;
+        case MFP_LPM_INPUT:
+                break;
+        default:
+                pr_warning("%s: invalid low power state for GPIO%d\n",
+                                __func__, gpio);
+                return -EINVAL;
+        }
+        return 0;
+}
+
 static int __mfp_config_gpio(unsigned gpio, unsigned long c)
 {
         unsigned long gafr, mask = GPIO_bit(gpio);
@@ -57,21 +79,8 @@ static int __mfp_config_gpio(unsigned gpio, unsigned long c)
         else
                 GPDR(gpio) &= ~mask;
 
-        /* low power state */
-        switch (c & MFP_LPM_STATE_MASK) {
-        case MFP_LPM_DRIVE_HIGH:
-                PGSR(gpio) |= mask;
-                break;
-        case MFP_LPM_DRIVE_LOW:
-                PGSR(gpio) &= ~mask;
-                break;
-        case MFP_LPM_INPUT:
-                break;
-        default:
-                pr_warning("%s: invalid low power state for GPIO%d\n",
-                                __func__, gpio);
+        if (__mfp_config_lpm(gpio, c & MFP_LPM_STATE_MASK))
                 return -EINVAL;
-        }
 
         /* give early warning if MFP_LPM_CAN_WAKEUP is set on the
          * configurations of those pins not able to wakeup
@@ -124,6 +133,20 @@ void pxa2xx_mfp_config(unsigned long *mfp_cfgs, int num)
         }
 }
 
+void pxa2xx_mfp_set_lpm(int mfp, unsigned long lpm)
+{
+        unsigned long flags;
+        int gpio;
+
+        gpio = __mfp_validate(mfp);
+        if (gpio < 0)
+                return;
+
+        local_irq_save(flags);
+        __mfp_config_lpm(gpio, lpm);
+        local_irq_restore(flags);
+}
+
 int gpio_set_wake(unsigned int gpio, unsigned int on)
 {
         struct gpio_desc *d;
diff --git a/include/asm-arm/arch-pxa/mfp-pxa2xx.h b/include/asm-arm/arch-pxa/mfp-pxa2xx.h
index db8d890d237c..8de1c0dae624 100644
--- a/include/asm-arm/arch-pxa/mfp-pxa2xx.h
+++ b/include/asm-arm/arch-pxa/mfp-pxa2xx.h
@@ -128,5 +128,6 @@
 #define GPIO84_GPIO     MFP_CFG_IN(GPIO84, AF0)
 
 extern void pxa2xx_mfp_config(unsigned long *mfp_cfgs, int num);
+extern void pxa2xx_mfp_set_lpm(int mfp, unsigned long lpm);
 extern int gpio_set_wake(unsigned int gpio, unsigned int on);
 #endif /* __ASM_ARCH_MFP_PXA2XX_H */