2 * scsi_pm.c Copyright (C) 2010 Alan Stern
4 * SCSI dynamic Power Management
5 * Initial version: Alan Stern <stern@rowland.harvard.edu>
8 #include <linux/pm_runtime.h>
9 #include <linux/export.h>
10 #include <linux/async.h>
12 #include <scsi/scsi.h>
13 #include <scsi/scsi_device.h>
14 #include <scsi/scsi_driver.h>
15 #include <scsi/scsi_host.h>
17 #include "scsi_priv.h"
19 #ifdef CONFIG_PM_SLEEP
21 static int do_scsi_suspend(struct device *dev, const struct dev_pm_ops *pm)
23 return pm && pm->suspend ? pm->suspend(dev) : 0;
26 static int do_scsi_freeze(struct device *dev, const struct dev_pm_ops *pm)
28 return pm && pm->freeze ? pm->freeze(dev) : 0;
31 static int do_scsi_poweroff(struct device *dev, const struct dev_pm_ops *pm)
33 return pm && pm->poweroff ? pm->poweroff(dev) : 0;
36 static int do_scsi_resume(struct device *dev, const struct dev_pm_ops *pm)
38 return pm && pm->resume ? pm->resume(dev) : 0;
41 static int do_scsi_thaw(struct device *dev, const struct dev_pm_ops *pm)
43 return pm && pm->thaw ? pm->thaw(dev) : 0;
46 static int do_scsi_restore(struct device *dev, const struct dev_pm_ops *pm)
48 return pm && pm->restore ? pm->restore(dev) : 0;
51 static int scsi_dev_type_suspend(struct device *dev,
52 int (*cb)(struct device *, const struct dev_pm_ops *))
54 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
57 /* flush pending in-flight resume operations, suspend is synchronous */
58 async_synchronize_full_domain(&scsi_sd_pm_domain);
60 err = scsi_device_quiesce(to_scsi_device(dev));
64 scsi_device_resume(to_scsi_device(dev));
66 dev_dbg(dev, "scsi suspend: %d\n", err);
70 static int scsi_dev_type_resume(struct device *dev,
71 int (*cb)(struct device *, const struct dev_pm_ops *))
73 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
77 scsi_device_resume(to_scsi_device(dev));
78 dev_dbg(dev, "scsi resume: %d\n", err);
81 pm_runtime_disable(dev);
82 pm_runtime_set_active(dev);
83 pm_runtime_enable(dev);
90 scsi_bus_suspend_common(struct device *dev,
91 int (*cb)(struct device *, const struct dev_pm_ops *))
95 if (scsi_is_sdev_device(dev)) {
97 * All the high-level SCSI drivers that implement runtime
98 * PM treat runtime suspend, system suspend, and system
99 * hibernate nearly identically. In all cases the requirements
100 * for runtime suspension are stricter.
102 if (pm_runtime_suspended(dev))
105 err = scsi_dev_type_suspend(dev, cb);
111 static void async_sdev_resume(void *dev, async_cookie_t cookie)
113 scsi_dev_type_resume(dev, do_scsi_resume);
116 static void async_sdev_thaw(void *dev, async_cookie_t cookie)
118 scsi_dev_type_resume(dev, do_scsi_thaw);
121 static void async_sdev_restore(void *dev, async_cookie_t cookie)
123 scsi_dev_type_resume(dev, do_scsi_restore);
126 static int scsi_bus_resume_common(struct device *dev,
127 int (*cb)(struct device *, const struct dev_pm_ops *))
131 if (!scsi_is_sdev_device(dev))
133 else if (cb == do_scsi_resume)
134 fn = async_sdev_resume;
135 else if (cb == do_scsi_thaw)
136 fn = async_sdev_thaw;
137 else if (cb == do_scsi_restore)
138 fn = async_sdev_restore;
143 async_schedule_domain(fn, dev, &scsi_sd_pm_domain);
146 * If a user has disabled async probing a likely reason
147 * is due to a storage enclosure that does not inject
148 * staggered spin-ups. For safety, make resume
149 * synchronous as well in that case.
151 if (strncmp(scsi_scan_type, "async", 5) != 0)
152 async_synchronize_full_domain(&scsi_sd_pm_domain);
154 pm_runtime_disable(dev);
155 pm_runtime_set_active(dev);
156 pm_runtime_enable(dev);
161 static int scsi_bus_prepare(struct device *dev)
163 if (scsi_is_sdev_device(dev)) {
164 /* sd probing uses async_schedule. Wait until it finishes. */
165 async_synchronize_full_domain(&scsi_sd_probe_domain);
167 } else if (scsi_is_host_device(dev)) {
168 /* Wait until async scanning is finished */
169 scsi_complete_async_scans();
174 static int scsi_bus_suspend(struct device *dev)
176 return scsi_bus_suspend_common(dev, do_scsi_suspend);
179 static int scsi_bus_resume(struct device *dev)
181 return scsi_bus_resume_common(dev, do_scsi_resume);
184 static int scsi_bus_freeze(struct device *dev)
186 return scsi_bus_suspend_common(dev, do_scsi_freeze);
189 static int scsi_bus_thaw(struct device *dev)
191 return scsi_bus_resume_common(dev, do_scsi_thaw);
194 static int scsi_bus_poweroff(struct device *dev)
196 return scsi_bus_suspend_common(dev, do_scsi_poweroff);
199 static int scsi_bus_restore(struct device *dev)
201 return scsi_bus_resume_common(dev, do_scsi_restore);
204 #else /* CONFIG_PM_SLEEP */
206 #define scsi_bus_prepare NULL
207 #define scsi_bus_suspend NULL
208 #define scsi_bus_resume NULL
209 #define scsi_bus_freeze NULL
210 #define scsi_bus_thaw NULL
211 #define scsi_bus_poweroff NULL
212 #define scsi_bus_restore NULL
214 #endif /* CONFIG_PM_SLEEP */
216 #ifdef CONFIG_PM_RUNTIME
218 static int sdev_runtime_suspend(struct device *dev)
220 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
221 struct scsi_device *sdev = to_scsi_device(dev);
224 err = blk_pre_runtime_suspend(sdev->request_queue);
227 if (pm && pm->runtime_suspend)
228 err = pm->runtime_suspend(dev);
229 blk_post_runtime_suspend(sdev->request_queue, err);
234 static int scsi_runtime_suspend(struct device *dev)
238 dev_dbg(dev, "scsi_runtime_suspend\n");
239 if (scsi_is_sdev_device(dev))
240 err = sdev_runtime_suspend(dev);
242 /* Insert hooks here for targets, hosts, and transport classes */
247 static int sdev_runtime_resume(struct device *dev)
249 struct scsi_device *sdev = to_scsi_device(dev);
250 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
253 blk_pre_runtime_resume(sdev->request_queue);
254 if (pm && pm->runtime_resume)
255 err = pm->runtime_resume(dev);
256 blk_post_runtime_resume(sdev->request_queue, err);
261 static int scsi_runtime_resume(struct device *dev)
265 dev_dbg(dev, "scsi_runtime_resume\n");
266 if (scsi_is_sdev_device(dev))
267 err = sdev_runtime_resume(dev);
269 /* Insert hooks here for targets, hosts, and transport classes */
274 static int scsi_runtime_idle(struct device *dev)
276 dev_dbg(dev, "scsi_runtime_idle\n");
278 /* Insert hooks here for targets, hosts, and transport classes */
280 if (scsi_is_sdev_device(dev)) {
281 pm_runtime_mark_last_busy(dev);
282 pm_runtime_autosuspend(dev);
289 int scsi_autopm_get_device(struct scsi_device *sdev)
293 err = pm_runtime_get_sync(&sdev->sdev_gendev);
294 if (err < 0 && err !=-EACCES)
295 pm_runtime_put_sync(&sdev->sdev_gendev);
300 EXPORT_SYMBOL_GPL(scsi_autopm_get_device);
302 void scsi_autopm_put_device(struct scsi_device *sdev)
304 pm_runtime_put_sync(&sdev->sdev_gendev);
306 EXPORT_SYMBOL_GPL(scsi_autopm_put_device);
308 void scsi_autopm_get_target(struct scsi_target *starget)
310 pm_runtime_get_sync(&starget->dev);
313 void scsi_autopm_put_target(struct scsi_target *starget)
315 pm_runtime_put_sync(&starget->dev);
318 int scsi_autopm_get_host(struct Scsi_Host *shost)
322 err = pm_runtime_get_sync(&shost->shost_gendev);
323 if (err < 0 && err !=-EACCES)
324 pm_runtime_put_sync(&shost->shost_gendev);
330 void scsi_autopm_put_host(struct Scsi_Host *shost)
332 pm_runtime_put_sync(&shost->shost_gendev);
337 #define scsi_runtime_suspend NULL
338 #define scsi_runtime_resume NULL
339 #define scsi_runtime_idle NULL
341 #endif /* CONFIG_PM_RUNTIME */
343 const struct dev_pm_ops scsi_bus_pm_ops = {
344 .prepare = scsi_bus_prepare,
345 .suspend = scsi_bus_suspend,
346 .resume = scsi_bus_resume,
347 .freeze = scsi_bus_freeze,
348 .thaw = scsi_bus_thaw,
349 .poweroff = scsi_bus_poweroff,
350 .restore = scsi_bus_restore,
351 .runtime_suspend = scsi_runtime_suspend,
352 .runtime_resume = scsi_runtime_resume,
353 .runtime_idle = scsi_runtime_idle,