ARM: 6758/1: amba: support pm ops

Support pm_ops in the AMBA bus, required to allow drivers to use runtime pm.
The implementation of AMBA bus pm ops is based on the platform bus
implementation.

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

2 files changed, 319 insertions, 23 deletions

diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index 43088996a07..6d2bb2524b6 100644
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -13,12 +13,13 @@
 #include <linux/string.h>
 #include <linux/slab.h>
 #include <linux/io.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
 #include <linux/amba/bus.h>
 
 #include <asm/irq.h>
 #include <asm/sizes.h>
 
-#define to_amba_device(d)       container_of(d, struct amba_device, dev)
 #define to_amba_driver(d)       container_of(d, struct amba_driver, drv)
 
 static const struct amba_id *
@@ -57,26 +58,6 @@ static int amba_uevent(struct device *dev, struct kobj_uevent_env *env)
 #define amba_uevent NULL
 #endif
 
-static int amba_suspend(struct device *dev, pm_message_t state)
-{
-        struct amba_driver *drv = to_amba_driver(dev->driver);
-        int ret = 0;
-
-        if (dev->driver && drv->suspend)
-                ret = drv->suspend(to_amba_device(dev), state);
-        return ret;
-}
-
-static int amba_resume(struct device *dev)
-{
-        struct amba_driver *drv = to_amba_driver(dev->driver);
-        int ret = 0;
-
-        if (dev->driver && drv->resume)
-                ret = drv->resume(to_amba_device(dev));
-        return ret;
-}
-
 #define amba_attr_func(name,fmt,arg...)                                 \
 static ssize_t name##_show(struct device *_dev,                         \
                            struct device_attribute *attr, char *buf)    \
@@ -102,6 +83,320 @@ static struct device_attribute amba_dev_attrs[] = {
         __ATTR_NULL,
 };
 
+#ifdef CONFIG_PM_SLEEP
+
+static int amba_legacy_suspend(struct device *dev, pm_message_t mesg)
+{
+        struct amba_driver *adrv = to_amba_driver(dev->driver);
+        struct amba_device *adev = to_amba_device(dev);
+        int ret = 0;
+
+        if (dev->driver && adrv->suspend)
+                ret = adrv->suspend(adev, mesg);
+
+        return ret;
+}
+
+static int amba_legacy_resume(struct device *dev)
+{
+        struct amba_driver *adrv = to_amba_driver(dev->driver);
+        struct amba_device *adev = to_amba_device(dev);
+        int ret = 0;
+
+        if (dev->driver && adrv->resume)
+                ret = adrv->resume(adev);
+
+        return ret;
+}
+
+static int amba_pm_prepare(struct device *dev)
+{
+        struct device_driver *drv = dev->driver;
+        int ret = 0;
+
+        if (drv && drv->pm && drv->pm->prepare)
+                ret = drv->pm->prepare(dev);
+
+        return ret;
+}
+
+static void amba_pm_complete(struct device *dev)
+{
+        struct device_driver *drv = dev->driver;
+
+        if (drv && drv->pm && drv->pm->complete)
+                drv->pm->complete(dev);
+}
+
+#else /* !CONFIG_PM_SLEEP */
+
+#define amba_pm_prepare         NULL
+#define amba_pm_complete                NULL
+
+#endif /* !CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_SUSPEND
+
+static int amba_pm_suspend(struct device *dev)
+{
+        struct device_driver *drv = dev->driver;
+        int ret = 0;
+
+        if (!drv)
+                return 0;
+
+        if (drv->pm) {
+                if (drv->pm->suspend)
+                        ret = drv->pm->suspend(dev);
+        } else {
+                ret = amba_legacy_suspend(dev, PMSG_SUSPEND);
+        }
+
+        return ret;
+}
+
+static int amba_pm_suspend_noirq(struct device *dev)
+{
+        struct device_driver *drv = dev->driver;
+        int ret = 0;
+
+        if (!drv)
+                return 0;
+
+        if (drv->pm) {
+                if (drv->pm->suspend_noirq)
+                        ret = drv->pm->suspend_noirq(dev);
+        }
+
+        return ret;
+}
+
+static int amba_pm_resume(struct device *dev)
+{
+        struct device_driver *drv = dev->driver;
+        int ret = 0;
+
+        if (!drv)
+                return 0;
+
+        if (drv->pm) {
+                if (drv->pm->resume)
+                        ret = drv->pm->resume(dev);
+        } else {
+                ret = amba_legacy_resume(dev);
+        }
+
+        return ret;
+}
+
+static int amba_pm_resume_noirq(struct device *dev)
+{
+        struct device_driver *drv = dev->driver;
+        int ret = 0;
+
+        if (!drv)
+                return 0;
+
+        if (drv->pm) {
+                if (drv->pm->resume_noirq)
+                        ret = drv->pm->resume_noirq(dev);
+        }
+
+        return ret;
+}
+
+#else /* !CONFIG_SUSPEND */
+
+#define amba_pm_suspend         NULL
+#define amba_pm_resume          NULL
+#define amba_pm_suspend_noirq   NULL
+#define amba_pm_resume_noirq    NULL
+
+#endif /* !CONFIG_SUSPEND */
+
+#ifdef CONFIG_HIBERNATION
+
+static int amba_pm_freeze(struct device *dev)
+{
+        struct device_driver *drv = dev->driver;
+        int ret = 0;
+
+        if (!drv)
+                return 0;
+
+        if (drv->pm) {
+                if (drv->pm->freeze)
+                        ret = drv->pm->freeze(dev);
+        } else {
+                ret = amba_legacy_suspend(dev, PMSG_FREEZE);
+        }
+
+        return ret;
+}
+
+static int amba_pm_freeze_noirq(struct device *dev)
+{
+        struct device_driver *drv = dev->driver;
+        int ret = 0;
+
+        if (!drv)
+                return 0;
+
+        if (drv->pm) {
+                if (drv->pm->freeze_noirq)
+                        ret = drv->pm->freeze_noirq(dev);
+        }
+
+        return ret;
+}
+
+static int amba_pm_thaw(struct device *dev)
+{
+        struct device_driver *drv = dev->driver;
+        int ret = 0;