s390/ptrace: get rid of long longs in psw_bits
[linux/fpc-iii.git] / drivers / scsi / scsi_pm.c
blobe4b7998379485454d26e39f6a5a91917a155ffbb
1 /*
2 * scsi_pm.c Copyright (C) 2010 Alan Stern
4 * SCSI dynamic Power Management
5 * Initial version: Alan Stern <stern@rowland.harvard.edu>
6 */
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;
55 int err;
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));
61 if (err == 0) {
62 err = cb(dev, pm);
63 if (err)
64 scsi_device_resume(to_scsi_device(dev));
66 dev_dbg(dev, "scsi suspend: %d\n", err);
67 return 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;
74 int err = 0;
76 err = cb(dev, pm);
77 scsi_device_resume(to_scsi_device(dev));
78 dev_dbg(dev, "scsi resume: %d\n", err);
80 if (err == 0) {
81 pm_runtime_disable(dev);
82 pm_runtime_set_active(dev);
83 pm_runtime_enable(dev);
86 return err;
89 static int
90 scsi_bus_suspend_common(struct device *dev,
91 int (*cb)(struct device *, const struct dev_pm_ops *))
93 int err = 0;
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))
103 return 0;
105 err = scsi_dev_type_suspend(dev, cb);
108 return err;
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 *))
129 async_func_t fn;
131 if (!scsi_is_sdev_device(dev))
132 fn = NULL;
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;
139 else
140 fn = NULL;
142 if (fn) {
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);
153 } else {
154 pm_runtime_disable(dev);
155 pm_runtime_set_active(dev);
156 pm_runtime_enable(dev);
158 return 0;
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();
171 return 0;
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 static int sdev_runtime_suspend(struct device *dev)
218 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
219 struct scsi_device *sdev = to_scsi_device(dev);
220 int err = 0;
222 if (pm && pm->runtime_suspend) {
223 err = blk_pre_runtime_suspend(sdev->request_queue);
224 if (err)
225 return err;
226 err = pm->runtime_suspend(dev);
227 blk_post_runtime_suspend(sdev->request_queue, err);
229 return err;
232 static int scsi_runtime_suspend(struct device *dev)
234 int err = 0;
236 dev_dbg(dev, "scsi_runtime_suspend\n");
237 if (scsi_is_sdev_device(dev))
238 err = sdev_runtime_suspend(dev);
240 /* Insert hooks here for targets, hosts, and transport classes */
242 return err;
245 static int sdev_runtime_resume(struct device *dev)
247 struct scsi_device *sdev = to_scsi_device(dev);
248 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
249 int err = 0;
251 if (pm && pm->runtime_resume) {
252 blk_pre_runtime_resume(sdev->request_queue);
253 err = pm->runtime_resume(dev);
254 blk_post_runtime_resume(sdev->request_queue, err);
256 return err;
259 static int scsi_runtime_resume(struct device *dev)
261 int err = 0;
263 dev_dbg(dev, "scsi_runtime_resume\n");
264 if (scsi_is_sdev_device(dev))
265 err = sdev_runtime_resume(dev);
267 /* Insert hooks here for targets, hosts, and transport classes */
269 return err;
272 static int scsi_runtime_idle(struct device *dev)
274 dev_dbg(dev, "scsi_runtime_idle\n");
276 /* Insert hooks here for targets, hosts, and transport classes */
278 if (scsi_is_sdev_device(dev)) {
279 pm_runtime_mark_last_busy(dev);
280 pm_runtime_autosuspend(dev);
281 return -EBUSY;
284 return 0;
287 int scsi_autopm_get_device(struct scsi_device *sdev)
289 int err;
291 err = pm_runtime_get_sync(&sdev->sdev_gendev);
292 if (err < 0 && err !=-EACCES)
293 pm_runtime_put_sync(&sdev->sdev_gendev);
294 else
295 err = 0;
296 return err;
298 EXPORT_SYMBOL_GPL(scsi_autopm_get_device);
300 void scsi_autopm_put_device(struct scsi_device *sdev)
302 pm_runtime_put_sync(&sdev->sdev_gendev);
304 EXPORT_SYMBOL_GPL(scsi_autopm_put_device);
306 void scsi_autopm_get_target(struct scsi_target *starget)
308 pm_runtime_get_sync(&starget->dev);
311 void scsi_autopm_put_target(struct scsi_target *starget)
313 pm_runtime_put_sync(&starget->dev);
316 int scsi_autopm_get_host(struct Scsi_Host *shost)
318 int err;
320 err = pm_runtime_get_sync(&shost->shost_gendev);
321 if (err < 0 && err !=-EACCES)
322 pm_runtime_put_sync(&shost->shost_gendev);
323 else
324 err = 0;
325 return err;
328 void scsi_autopm_put_host(struct Scsi_Host *shost)
330 pm_runtime_put_sync(&shost->shost_gendev);
333 const struct dev_pm_ops scsi_bus_pm_ops = {
334 .prepare = scsi_bus_prepare,
335 .suspend = scsi_bus_suspend,
336 .resume = scsi_bus_resume,
337 .freeze = scsi_bus_freeze,
338 .thaw = scsi_bus_thaw,
339 .poweroff = scsi_bus_poweroff,
340 .restore = scsi_bus_restore,
341 .runtime_suspend = scsi_runtime_suspend,
342 .runtime_resume = scsi_runtime_resume,
343 .runtime_idle = scsi_runtime_idle,