[PATCH 2/2] ARM: ABMA: Disable/Enable interface clock from suspend/resume

[Vipul Kumar Samar]

AMBA devices interface clock is disabled in RTPM suspend/resume hooks
but not in conventional hooks.

This patch adds support to disable/enable clock for conventional
suspend/resume calls.

Signed-off-by: Vipul Kumar Samar <vipulkumar.samar at st.com>
---
 drivers/amba/bus.c |   42 +++++++++++++++++++++++++++++++++++++++---
 1 file changed, 39 insertions(+), 3 deletions(-)

diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index b7e7285..ded3d98 100644
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -120,6 +120,7 @@ static int amba_legacy_resume(struct device *dev)
 static int amba_pm_suspend(struct device *dev)
 {
 	struct device_driver *drv = dev->driver;
+	struct amba_device *pcdev = to_amba_device(dev);
 	int ret = 0;
 
 	if (!drv)
@@ -132,16 +133,27 @@ static int amba_pm_suspend(struct device *dev)
 		ret = amba_legacy_suspend(dev, PMSG_SUSPEND);
 	}
 
+	if (!ret)
+		clk_disable(pcdev->pclk);
+
 	return ret;
 }
 
 static int amba_pm_resume(struct device *dev)
 {
 	struct device_driver *drv = dev->driver;
+	struct amba_device *pcdev = to_amba_device(dev);
 	int ret = 0;
 
-	if (!drv)
+	if (!drv) {
 		return 0;
+	} else {
+		ret = clk_enable(pcdev->pclk);
+		if (ret) {
+			dev_err(dev, "Resume: Clk enable failed");
+			return ret;
+		}
+	}
 
 	if (drv->pm) {
 		if (drv->pm->resume)
@@ -165,6 +177,7 @@ static int amba_pm_resume(struct device *dev)
 static int amba_pm_freeze(struct device *dev)
 {
 	struct device_driver *drv = dev->driver;
+	struct amba_device *pcdev = to_amba_device(dev);
 	int ret = 0;
 
 	if (!drv)
@@ -177,16 +190,27 @@ static int amba_pm_freeze(struct device *dev)
 		ret = amba_legacy_suspend(dev, PMSG_FREEZE);
 	}
 
+	if (!ret)
+		clk_disable(pcdev->pclk);
+
 	return ret;
 }
 
 static int amba_pm_thaw(struct device *dev)
 {
 	struct device_driver *drv = dev->driver;
+	struct amba_device *pcdev = to_amba_device(dev);
 	int ret = 0;
 
-	if (!drv)
+	if (!drv) {
 		return 0;
+	} else {
+		ret = clk_enable(pcdev->pclk);
+		if (ret) {
+			dev_err(dev, "Thaw: Clk enable failed");
+			return ret;
+		}
+	}
 
 	if (drv->pm) {
 		if (drv->pm->thaw)
@@ -201,6 +225,7 @@ static int amba_pm_thaw(struct device *dev)
 static int amba_pm_poweroff(struct device *dev)
 {
 	struct device_driver *drv = dev->driver;
+	struct amba_device *pcdev = to_amba_device(dev);
 	int ret = 0;
 
 	if (!drv)
@@ -213,16 +238,27 @@ static int amba_pm_poweroff(struct device *dev)
 		ret = amba_legacy_suspend(dev, PMSG_HIBERNATE);
 	}
 
+	if (!ret)
+		clk_disable(pcdev->pclk);
+
 	return ret;
 }
 
 static int amba_pm_restore(struct device *dev)
 {
 	struct device_driver *drv = dev->driver;
+	struct amba_device *pcdev = to_amba_device(dev);
 	int ret = 0;
 
-	if (!drv)
+	if (!drv) {
 		return 0;
+	} else {
+		ret = clk_enable(pcdev->pclk);
+		if (ret) {
+			dev_err(dev, "Restore: Clk enable failed");
+			return ret;
+		}
+	}
 
 	if (drv->pm) {
 		if (drv->pm->restore)
-- 
1.7.10