summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/scsi_pm.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/scsi/scsi_pm.c')
-rw-r--r--drivers/scsi/scsi_pm.c273
1 files changed, 273 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c
new file mode 100644
index 000000000..d581613d8
--- /dev/null
+++ b/drivers/scsi/scsi_pm.c
@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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 <linux/export.h>
+#include <linux/blk-pm.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_driver.h>
+#include <scsi/scsi_host.h>
+
+#include "scsi_priv.h"
+
+#ifdef CONFIG_PM_SLEEP
+
+static int do_scsi_suspend(struct device *dev, const struct dev_pm_ops *pm)
+{
+ return pm && pm->suspend ? pm->suspend(dev) : 0;
+}
+
+static int do_scsi_freeze(struct device *dev, const struct dev_pm_ops *pm)
+{
+ return pm && pm->freeze ? pm->freeze(dev) : 0;
+}
+
+static int do_scsi_poweroff(struct device *dev, const struct dev_pm_ops *pm)
+{
+ return pm && pm->poweroff ? pm->poweroff(dev) : 0;
+}
+
+static int do_scsi_resume(struct device *dev, const struct dev_pm_ops *pm)
+{
+ return pm && pm->resume ? pm->resume(dev) : 0;
+}
+
+static int do_scsi_thaw(struct device *dev, const struct dev_pm_ops *pm)
+{
+ return pm && pm->thaw ? pm->thaw(dev) : 0;
+}
+
+static int do_scsi_restore(struct device *dev, const struct dev_pm_ops *pm)
+{
+ return pm && pm->restore ? pm->restore(dev) : 0;
+}
+
+static int scsi_dev_type_suspend(struct device *dev,
+ int (*cb)(struct device *, const struct dev_pm_ops *))
+{
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+ int err;
+
+ err = scsi_device_quiesce(to_scsi_device(dev));
+ if (err == 0) {
+ err = cb(dev, pm);
+ if (err)
+ scsi_device_resume(to_scsi_device(dev));
+ }
+ dev_dbg(dev, "scsi suspend: %d\n", err);
+ return err;
+}
+
+static int
+scsi_bus_suspend_common(struct device *dev,
+ int (*cb)(struct device *, const struct dev_pm_ops *))
+{
+ if (!scsi_is_sdev_device(dev))
+ return 0;
+
+ return scsi_dev_type_suspend(dev, cb);
+}
+
+static int scsi_bus_resume_common(struct device *dev,
+ int (*cb)(struct device *, const struct dev_pm_ops *))
+{
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+ int err;
+
+ if (!scsi_is_sdev_device(dev))
+ return 0;
+
+ err = cb(dev, pm);
+ scsi_device_resume(to_scsi_device(dev));
+ dev_dbg(dev, "scsi resume: %d\n", err);
+
+ return err;
+}
+
+static int scsi_bus_prepare(struct device *dev)
+{
+ if (scsi_is_host_device(dev)) {
+ /* Wait until async scanning is finished */
+ scsi_complete_async_scans();
+ }
+ return 0;
+}
+
+static int scsi_bus_suspend(struct device *dev)
+{
+ return scsi_bus_suspend_common(dev, do_scsi_suspend);
+}
+
+static int scsi_bus_resume(struct device *dev)
+{
+ return scsi_bus_resume_common(dev, do_scsi_resume);
+}
+
+static int scsi_bus_freeze(struct device *dev)
+{
+ return scsi_bus_suspend_common(dev, do_scsi_freeze);
+}
+
+static int scsi_bus_thaw(struct device *dev)
+{
+ return scsi_bus_resume_common(dev, do_scsi_thaw);
+}
+
+static int scsi_bus_poweroff(struct device *dev)
+{
+ return scsi_bus_suspend_common(dev, do_scsi_poweroff);
+}
+
+static int scsi_bus_restore(struct device *dev)
+{
+ return scsi_bus_resume_common(dev, do_scsi_restore);
+}
+
+#else /* CONFIG_PM_SLEEP */
+
+#define scsi_bus_prepare NULL
+#define scsi_bus_suspend NULL
+#define scsi_bus_resume NULL
+#define scsi_bus_freeze NULL
+#define scsi_bus_thaw NULL
+#define scsi_bus_poweroff NULL
+#define scsi_bus_restore NULL
+
+#endif /* CONFIG_PM_SLEEP */
+
+static int sdev_runtime_suspend(struct device *dev)
+{
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+ struct scsi_device *sdev = to_scsi_device(dev);
+ int err = 0;
+
+ err = blk_pre_runtime_suspend(sdev->request_queue);
+ if (err)
+ return err;
+ if (pm && pm->runtime_suspend)
+ err = pm->runtime_suspend(dev);
+ blk_post_runtime_suspend(sdev->request_queue, err);
+
+ return err;
+}
+
+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 = sdev_runtime_suspend(dev);
+
+ /* Insert hooks here for targets, hosts, and transport classes */
+
+ return err;
+}
+
+static int sdev_runtime_resume(struct device *dev)
+{
+ struct scsi_device *sdev = to_scsi_device(dev);
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+ int err = 0;
+
+ blk_pre_runtime_resume(sdev->request_queue);
+ if (pm && pm->runtime_resume)
+ err = pm->runtime_resume(dev);
+ blk_post_runtime_resume(sdev->request_queue);
+
+ 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 = sdev_runtime_resume(dev);
+
+ /* Insert hooks here for targets, hosts, and transport classes */
+
+ return err;
+}
+
+static int scsi_runtime_idle(struct device *dev)
+{
+ dev_dbg(dev, "scsi_runtime_idle\n");
+
+ /* Insert hooks here for targets, hosts, and transport classes */
+
+ if (scsi_is_sdev_device(dev)) {
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_autosuspend(dev);
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+int scsi_autopm_get_device(struct scsi_device *sdev)
+{
+ int err;
+
+ err = pm_runtime_get_sync(&sdev->sdev_gendev);
+ if (err < 0 && err !=-EACCES)
+ pm_runtime_put_sync(&sdev->sdev_gendev);
+ else
+ 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 && err !=-EACCES)
+ pm_runtime_put_sync(&shost->shost_gendev);
+ else
+ err = 0;
+ return err;
+}
+
+void scsi_autopm_put_host(struct Scsi_Host *shost)
+{
+ pm_runtime_put_sync(&shost->shost_gendev);
+}
+
+const struct dev_pm_ops scsi_bus_pm_ops = {
+ .prepare = scsi_bus_prepare,
+ .suspend = scsi_bus_suspend,
+ .resume = scsi_bus_resume,
+ .freeze = scsi_bus_freeze,
+ .thaw = scsi_bus_thaw,
+ .poweroff = scsi_bus_poweroff,
+ .restore = scsi_bus_restore,
+ .runtime_suspend = scsi_runtime_suspend,
+ .runtime_resume = scsi_runtime_resume,
+ .runtime_idle = scsi_runtime_idle,
+};