| /* |
| * 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" |
| |
| static int do_scsi_runtime_resume(struct device *dev, |
| const struct dev_pm_ops *pm); |
| |
| #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 && (cb != do_scsi_runtime_resume)) { |
| pm_runtime_disable(dev); |
| err = pm_runtime_set_active(dev); |
| pm_runtime_enable(dev); |
| |
| /* |
| * 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 (!err && scsi_is_sdev_device(dev)) { |
| struct scsi_device *sdev = to_scsi_device(dev); |
| |
| if (sdev->request_queue->dev) |
| blk_set_runtime_active(sdev->request_queue); |
| } |
| } |
| |
| 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; |
| |
| 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 |
| |
| static inline int |
| scsi_dev_type_suspend(struct device *dev, |
| int (*cb)(struct device *, const struct dev_pm_ops *)) |
| { |
| return 0; |
| } |
| |
| static inline int |
| scsi_dev_type_resume(struct device *dev, |
| int (*cb)(struct device *, const struct dev_pm_ops *)) |
| { |
| return 0; |
| } |
| #endif /* CONFIG_PM_SLEEP */ |
| |
| static int do_scsi_runtime_suspend(struct device *dev, |
| const struct dev_pm_ops *pm) |
| { |
| return pm && pm->runtime_suspend ? pm->runtime_suspend(dev) : 0; |
| } |
| |
| static int do_scsi_runtime_resume(struct device *dev, |
| const struct dev_pm_ops *pm) |
| { |
| return pm && pm->runtime_resume ? pm->runtime_resume(dev) : 0; |
| } |
| |
| 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; |
| |
| if (!sdev->request_queue->dev) { |
| err = scsi_dev_type_suspend(dev, do_scsi_runtime_suspend); |
| if (err == -EAGAIN) |
| pm_schedule_suspend(dev, jiffies_to_msecs( |
| round_jiffies_up_relative(HZ/10))); |
| return err; |
| } |
| |
| 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; |
| |
| if (!sdev->request_queue->dev) |
| return scsi_dev_type_resume(dev, do_scsi_runtime_resume); |
| |
| 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, |
| }; |