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Diffstat (limited to 'drivers/scsi/scsi_pm.c')
-rw-r--r--drivers/scsi/scsi_pm.c206
1 files changed, 206 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c
new file mode 100644
index 000000000000..d70e91ae60af
--- /dev/null
+++ b/drivers/scsi/scsi_pm.c
@@ -0,0 +1,206 @@
+/*
+ * scsi_pm.c Copyright (C) 2010 Alan Stern
+ *
+ * SCSI dynamic Power Management
+ * Initial version: Alan Stern <stern@rowland.harvard.edu>
+ */
+
+#include <linux/pm_runtime.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_driver.h>
+#include <scsi/scsi_host.h>
+
+#include "scsi_priv.h"
+
+static int scsi_dev_type_suspend(struct device *dev, pm_message_t msg)
+{
+ struct device_driver *drv;
+ int err;
+
+ err = scsi_device_quiesce(to_scsi_device(dev));
+ if (err == 0) {
+ drv = dev->driver;
+ if (drv && drv->suspend)
+ err = drv->suspend(dev, msg);
+ }
+ dev_dbg(dev, "scsi suspend: %d\n", err);
+ return err;
+}
+
+static int scsi_dev_type_resume(struct device *dev)
+{
+ struct device_driver *drv;
+ int err = 0;
+
+ drv = dev->driver;
+ if (drv && drv->resume)
+ err = drv->resume(dev);
+ scsi_device_resume(to_scsi_device(dev));
+ dev_dbg(dev, "scsi resume: %d\n", err);
+ return err;
+}
+
+#ifdef CONFIG_PM_SLEEP
+
+static int scsi_bus_suspend_common(struct device *dev, pm_message_t msg)
+{
+ int err = 0;
+
+ if (scsi_is_sdev_device(dev))
+ err = scsi_dev_type_suspend(dev, msg);
+ return err;
+}
+
+static int scsi_bus_resume_common(struct device *dev)
+{
+ int err = 0;
+
+ if (scsi_is_sdev_device(dev))
+ err = scsi_dev_type_resume(dev);
+
+ if (err == 0) {
+ pm_runtime_disable(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+ }
+ return err;
+}
+
+static int scsi_bus_suspend(struct device *dev)
+{
+ return scsi_bus_suspend_common(dev, PMSG_SUSPEND);
+}
+
+static int scsi_bus_freeze(struct device *dev)
+{
+ return scsi_bus_suspend_common(dev, PMSG_FREEZE);
+}
+
+static int scsi_bus_poweroff(struct device *dev)
+{
+ return scsi_bus_suspend_common(dev, PMSG_HIBERNATE);
+}
+
+#else /* CONFIG_PM_SLEEP */
+
+#define scsi_bus_resume_common NULL
+#define scsi_bus_suspend NULL
+#define scsi_bus_freeze NULL
+#define scsi_bus_poweroff NULL
+
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM_RUNTIME
+
+static int scsi_runtime_suspend(struct device *dev)
+{
+ int err = 0;
+
+ dev_dbg(dev, "scsi_runtime_suspend\n");
+ if (scsi_is_sdev_device(dev)) {
+ err = scsi_dev_type_suspend(dev, PMSG_AUTO_SUSPEND);
+ if (err == -EAGAIN)
+ pm_schedule_suspend(dev, jiffies_to_msecs(
+ round_jiffies_up_relative(HZ/10)));
+ }
+
+ /* Insert hooks here for targets, hosts, and transport classes */
+
+ return err;
+}
+
+static int scsi_runtime_resume(struct device *dev)
+{
+ int err = 0;
+
+ dev_dbg(dev, "scsi_runtime_resume\n");
+ if (scsi_is_sdev_device(dev))
+ err = scsi_dev_type_resume(dev);
+
+ /* Insert hooks here for targets, hosts, and transport classes */
+
+ return err;
+}
+
+static int scsi_runtime_idle(struct device *dev)
+{
+ int err;
+
+ dev_dbg(dev, "scsi_runtime_idle\n");
+
+ /* Insert hooks here for targets, hosts, and transport classes */
+
+ if (scsi_is_sdev_device(dev))
+ err = pm_schedule_suspend(dev, 100);
+ else
+ err = pm_runtime_suspend(dev);
+ return err;
+}
+
+int scsi_autopm_get_device(struct scsi_device *sdev)
+{
+ int err;
+
+ err = pm_runtime_get_sync(&sdev->sdev_gendev);
+ if (err < 0)
+ pm_runtime_put_sync(&sdev->sdev_gendev);
+ else if (err > 0)
+ err = 0;
+ return err;
+}
+EXPORT_SYMBOL_GPL(scsi_autopm_get_device);
+
+void scsi_autopm_put_device(struct scsi_device *sdev)
+{
+ pm_runtime_put_sync(&sdev->sdev_gendev);
+}
+EXPORT_SYMBOL_GPL(scsi_autopm_put_device);
+
+void scsi_autopm_get_target(struct scsi_target *starget)
+{
+ pm_runtime_get_sync(&starget->dev);
+}
+
+void scsi_autopm_put_target(struct scsi_target *starget)
+{
+ pm_runtime_put_sync(&starget->dev);
+}
+
+int scsi_autopm_get_host(struct Scsi_Host *shost)
+{
+ int err;
+
+ err = pm_runtime_get_sync(&shost->shost_gendev);
+ if (err < 0)
+ pm_runtime_put_sync(&shost->shost_gendev);
+ else if (err > 0)
+ err = 0;
+ return err;
+}
+
+void scsi_autopm_put_host(struct Scsi_Host *shost)
+{
+ pm_runtime_put_sync(&shost->shost_gendev);
+}
+
+#else
+
+#define scsi_runtime_suspend NULL
+#define scsi_runtime_resume NULL
+#define scsi_runtime_idle NULL
+
+#endif /* CONFIG_PM_RUNTIME */
+
+const struct dev_pm_ops scsi_bus_pm_ops = {
+ .suspend = scsi_bus_suspend,
+ .resume = scsi_bus_resume_common,
+ .freeze = scsi_bus_freeze,
+ .thaw = scsi_bus_resume_common,
+ .poweroff = scsi_bus_poweroff,
+ .restore = scsi_bus_resume_common,
+ .runtime_suspend = scsi_runtime_suspend,
+ .runtime_resume = scsi_runtime_resume,
+ .runtime_idle = scsi_runtime_idle,
+};