v4.19.13 snapshot.
diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c
new file mode 100644
index 0000000..b44c1bb
--- /dev/null
+++ b/drivers/scsi/scsi_pm.c
@@ -0,0 +1,354 @@
+/*
+ * 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/async.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;
+
+ /* flush pending in-flight resume operations, suspend is synchronous */
+ async_synchronize_full_domain(&scsi_sd_pm_domain);
+
+ 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_dev_type_resume(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 = 0;
+
+ err = cb(dev, pm);
+ scsi_device_resume(to_scsi_device(dev));
+ dev_dbg(dev, "scsi resume: %d\n", err);
+
+ if (err == 0) {
+ pm_runtime_disable(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+ }
+
+ return err;
+}
+
+static int
+scsi_bus_suspend_common(struct device *dev,
+ int (*cb)(struct device *, const struct dev_pm_ops *))
+{
+ int err = 0;
+
+ if (scsi_is_sdev_device(dev)) {
+ /*
+ * All the high-level SCSI drivers that implement runtime
+ * PM treat runtime suspend, system suspend, and system
+ * hibernate nearly identically. In all cases the requirements
+ * for runtime suspension are stricter.
+ */
+ if (pm_runtime_suspended(dev))
+ return 0;
+
+ err = scsi_dev_type_suspend(dev, cb);
+ }
+
+ return err;
+}
+
+static void async_sdev_resume(void *dev, async_cookie_t cookie)
+{
+ scsi_dev_type_resume(dev, do_scsi_resume);
+}
+
+static void async_sdev_thaw(void *dev, async_cookie_t cookie)
+{
+ scsi_dev_type_resume(dev, do_scsi_thaw);
+}
+
+static void async_sdev_restore(void *dev, async_cookie_t cookie)
+{
+ scsi_dev_type_resume(dev, do_scsi_restore);
+}
+
+static int scsi_bus_resume_common(struct device *dev,
+ int (*cb)(struct device *, const struct dev_pm_ops *))
+{
+ async_func_t fn;
+
+ if (!scsi_is_sdev_device(dev))
+ fn = NULL;
+ else if (cb == do_scsi_resume)
+ fn = async_sdev_resume;
+ else if (cb == do_scsi_thaw)
+ fn = async_sdev_thaw;
+ else if (cb == do_scsi_restore)
+ fn = async_sdev_restore;
+ else
+ fn = NULL;
+
+ /*
+ * Forcibly set runtime PM status of request queue to "active" to
+ * make sure we can again get requests from the queue (see also
+ * blk_pm_peek_request()).
+ *
+ * The resume hook will correct runtime PM status of the disk.
+ */
+ if (scsi_is_sdev_device(dev) && pm_runtime_suspended(dev))
+ blk_set_runtime_active(to_scsi_device(dev)->request_queue);
+
+ if (fn) {
+ async_schedule_domain(fn, dev, &scsi_sd_pm_domain);
+
+ /*
+ * If a user has disabled async probing a likely reason
+ * is due to a storage enclosure that does not inject
+ * staggered spin-ups. For safety, make resume
+ * synchronous as well in that case.
+ */
+ if (strncmp(scsi_scan_type, "async", 5) != 0)
+ async_synchronize_full_domain(&scsi_sd_pm_domain);
+ } else {
+ pm_runtime_disable(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+ }
+ return 0;
+}
+
+static int scsi_bus_prepare(struct device *dev)
+{
+ if (scsi_is_sdev_device(dev)) {
+ /* sd probing uses async_schedule. Wait until it finishes. */
+ async_synchronize_full_domain(&scsi_sd_probe_domain);
+
+ } else 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, err);
+
+ 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,
+};