mei: me: add runtime pm framework

Add runtime pm framework for ME devices.
The runtime pm handlers are used to run
me power gating isolation protocol

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 100 insertions, 2 deletions

diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c
index a725365..b9a4bb5 100644
--- a/drivers/misc/mei/hbm.c
+++ b/drivers/misc/mei/hbm.c
@@ -19,6 +19,7 @@
 #include <linux/sched.h>
 #include <linux/wait.h>
 #include <linux/mei.h>
+#include <linux/pm_runtime.h>
 
 #include "mei_dev.h"
 #include "hbm.h"
@@ -742,6 +743,13 @@ int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
 		if (waitqueue_active(&dev->wait_pg))
 			wake_up(&dev->wait_pg);
+		else
+			/*
+			* If the driver is not waiting on this then
+			* this is HW initiated exit from PG.
+			* Start runtime pm resume sequence to exit from PG.
+			*/
+			pm_request_resume(&dev->pdev->dev);
 		break;
 
 	case HOST_CLIENT_PROPERTIES_RES_CMD:
diff --git a/drivers/misc/mei/hw-me.h b/drivers/misc/mei/hw-me.h
index 8b41282..0a75ab8 100644
--- a/drivers/misc/mei/hw-me.h
+++ b/drivers/misc/mei/hw-me.h
@@ -24,6 +24,8 @@
 #include "mei_dev.h"
 #include "client.h"
 
+#define MEI_ME_RPM_TIMEOUT    500 /* ms */
+
 struct mei_me_hw {
 	void __iomem *mem_addr;
 	/*
diff --git a/drivers/misc/mei/pci-me.c b/drivers/misc/mei/pci-me.c
index 95889e2..fcbf270 100644
--- a/drivers/misc/mei/pci-me.c
+++ b/drivers/misc/mei/pci-me.c
@@ -33,6 +33,8 @@
 #include <linux/interrupt.h>
 #include <linux/miscdevice.h>
 
+#include <linux/pm_runtime.h>
+
 #include <linux/mei.h>
 
 #include "mei_dev.h"
@@ -212,6 +214,9 @@ static int mei_me_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto release_irq;
 	}
 
+	pm_runtime_set_autosuspend_delay(&pdev->dev, MEI_ME_RPM_TIMEOUT);
+	pm_runtime_use_autosuspend(&pdev->dev);
+
 	err = mei_register(dev);
 	if (err)
 		goto release_irq;
@@ -220,6 +225,9 @@ static int mei_me_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	schedule_delayed_work(&dev->timer_work, HZ);
 
+	if (mei_pg_is_enabled(dev))
+		pm_runtime_put_noidle(&pdev->dev);
+
 	dev_dbg(&pdev->dev, "initialization successful.\n");
 
 	return 0;
@@ -259,6 +267,9 @@ static void mei_me_remove(struct pci_dev *pdev)
 	if (!dev)
 		return;
 
+	if (mei_pg_is_enabled(dev))
+		pm_runtime_get_noresume(&pdev->dev);
+
 	hw = to_me_hw(dev);
 
 
@@ -343,12 +354,89 @@ static int mei_me_pci_resume(struct device *device)
 
 	return 0;
 }
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM_RUNTIME
+static int mei_me_pm_runtime_idle(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev;
+
+	dev_dbg(&pdev->dev, "rpm: me: runtime_idle\n");
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return -ENODEV;
+	if (mei_write_is_idle(dev))
+		pm_schedule_suspend(device, MEI_ME_RPM_TIMEOUT * 2);
+
+	return -EBUSY;
+}
+
+static int mei_me_pm_runtime_suspend(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev;
+	int ret;
+
+	dev_dbg(&pdev->dev, "rpm: me: runtime suspend\n");
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	if (mei_write_is_idle(dev))
+		ret = mei_me_pg_set_sync(dev);
+	else
+		ret = -EAGAIN;
+
+	mutex_unlock(&dev->device_lock);
+
+	dev_dbg(&pdev->dev, "rpm: me: runtime suspend ret=%d\n", ret);
+
+	return ret;
+}
+
+static int mei_me_pm_runtime_resume(struct device *device)
+{
+	struct pci_dev *pdev = to_pci_dev(device);
+	struct mei_device *dev;
+	int ret;
+
+	dev_dbg(&pdev->dev, "rpm: me: runtime resume\n");
+
+	dev = pci_get_drvdata(pdev);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	ret = mei_me_pg_unset_sync(dev);
+
+	mutex_unlock(&dev->device_lock);
+
+	dev_dbg(&pdev->dev, "rpm: me: runtime resume ret = %d\n", ret);
+
+	return ret;
+}
+#endif /* CONFIG_PM_RUNTIME */
+
+#ifdef CONFIG_PM
+static const struct dev_pm_ops mei_me_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(mei_me_pci_suspend,
+				mei_me_pci_resume)
+	SET_RUNTIME_PM_OPS(
+		mei_me_pm_runtime_suspend,
+		mei_me_pm_runtime_resume,
+		mei_me_pm_runtime_idle)
+};
 
-static SIMPLE_DEV_PM_OPS(mei_me_pm_ops, mei_me_pci_suspend, mei_me_pci_resume);
 #define MEI_ME_PM_OPS	(&mei_me_pm_ops)
 #else
 #define MEI_ME_PM_OPS	NULL
-#endif /* CONFIG_PM_SLEEP */
+#endif /* CONFIG_PM */
 /*
  *  PCI driver structure
  */