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 static int scsi_dev_type_suspend(struct device *dev, pm_message_t msg)
21 struct device_driver *drv;
24 err = scsi_device_quiesce(to_scsi_device(dev));
27 if (drv && drv->suspend)
28 err = drv->suspend(dev, msg);
30 dev_dbg(dev, "scsi suspend: %d\n", err);
34 static int scsi_dev_type_resume(struct device *dev)
36 struct device_driver *drv;
40 if (drv && drv->resume)
41 err = drv->resume(dev);
42 scsi_device_resume(to_scsi_device(dev));
43 dev_dbg(dev, "scsi resume: %d\n", err);
47 #ifdef CONFIG_PM_SLEEP
49 static int scsi_bus_suspend_common(struct device *dev, pm_message_t msg)
53 if (scsi_is_sdev_device(dev))
54 err = scsi_dev_type_suspend(dev, msg);
58 static int scsi_bus_resume_common(struct device *dev)
62 if (scsi_is_sdev_device(dev))
63 err = scsi_dev_type_resume(dev);
66 pm_runtime_disable(dev);
67 pm_runtime_set_active(dev);
68 pm_runtime_enable(dev);
73 static int scsi_bus_prepare(struct device *dev)
75 if (scsi_is_sdev_device(dev)) {
76 /* sd probing uses async_schedule. Wait until it finishes. */
77 async_synchronize_full();
79 } else if (scsi_is_host_device(dev)) {
80 /* Wait until async scanning is finished */
81 scsi_complete_async_scans();
86 static int scsi_bus_suspend(struct device *dev)
88 return scsi_bus_suspend_common(dev, PMSG_SUSPEND);
91 static int scsi_bus_freeze(struct device *dev)
93 return scsi_bus_suspend_common(dev, PMSG_FREEZE);
96 static int scsi_bus_poweroff(struct device *dev)
98 return scsi_bus_suspend_common(dev, PMSG_HIBERNATE);
101 #else /* CONFIG_PM_SLEEP */
103 #define scsi_bus_resume_common NULL
104 #define scsi_bus_prepare NULL
105 #define scsi_bus_suspend NULL
106 #define scsi_bus_freeze NULL
107 #define scsi_bus_poweroff NULL
109 #endif /* CONFIG_PM_SLEEP */
111 #ifdef CONFIG_PM_RUNTIME
113 static int scsi_runtime_suspend(struct device *dev)
117 dev_dbg(dev, "scsi_runtime_suspend\n");
118 if (scsi_is_sdev_device(dev)) {
119 err = scsi_dev_type_suspend(dev, PMSG_AUTO_SUSPEND);
121 pm_schedule_suspend(dev, jiffies_to_msecs(
122 round_jiffies_up_relative(HZ/10)));
125 /* Insert hooks here for targets, hosts, and transport classes */
130 static int scsi_runtime_resume(struct device *dev)
134 dev_dbg(dev, "scsi_runtime_resume\n");
135 if (scsi_is_sdev_device(dev))
136 err = scsi_dev_type_resume(dev);
138 /* Insert hooks here for targets, hosts, and transport classes */
143 static int scsi_runtime_idle(struct device *dev)
147 dev_dbg(dev, "scsi_runtime_idle\n");
149 /* Insert hooks here for targets, hosts, and transport classes */
151 if (scsi_is_sdev_device(dev))
152 err = pm_schedule_suspend(dev, 100);
154 err = pm_runtime_suspend(dev);
158 int scsi_autopm_get_device(struct scsi_device *sdev)
162 err = pm_runtime_get_sync(&sdev->sdev_gendev);
163 if (err < 0 && err !=-EACCES)
164 pm_runtime_put_sync(&sdev->sdev_gendev);
169 EXPORT_SYMBOL_GPL(scsi_autopm_get_device);
171 void scsi_autopm_put_device(struct scsi_device *sdev)
173 pm_runtime_put_sync(&sdev->sdev_gendev);
175 EXPORT_SYMBOL_GPL(scsi_autopm_put_device);
177 void scsi_autopm_get_target(struct scsi_target *starget)
179 pm_runtime_get_sync(&starget->dev);
182 void scsi_autopm_put_target(struct scsi_target *starget)
184 pm_runtime_put_sync(&starget->dev);
187 int scsi_autopm_get_host(struct Scsi_Host *shost)
191 err = pm_runtime_get_sync(&shost->shost_gendev);
192 if (err < 0 && err !=-EACCES)
193 pm_runtime_put_sync(&shost->shost_gendev);
199 void scsi_autopm_put_host(struct Scsi_Host *shost)
201 pm_runtime_put_sync(&shost->shost_gendev);
206 #define scsi_runtime_suspend NULL
207 #define scsi_runtime_resume NULL
208 #define scsi_runtime_idle NULL
210 #endif /* CONFIG_PM_RUNTIME */
212 const struct dev_pm_ops scsi_bus_pm_ops = {
213 .prepare = scsi_bus_prepare,
214 .suspend = scsi_bus_suspend,
215 .resume = scsi_bus_resume_common,
216 .freeze = scsi_bus_freeze,
217 .thaw = scsi_bus_resume_common,
218 .poweroff = scsi_bus_poweroff,
219 .restore = scsi_bus_resume_common,
220 .runtime_suspend = scsi_runtime_suspend,
221 .runtime_resume = scsi_runtime_resume,
222 .runtime_idle = scsi_runtime_idle,