tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * scsi_pm.c Copyright (C) 2010 Alan Stern
3 *
4 * SCSI dynamic Power Management
5 * Initial version: Alan Stern <stern@rowland.harvard.edu>
6 */
7
8#include <linux/pm_runtime.h>
9#include <linux/export.h>
10
11#include <scsi/scsi.h>
12#include <scsi/scsi_device.h>
13#include <scsi/scsi_driver.h>
14#include <scsi/scsi_host.h>
15
16#include "scsi_priv.h"
17
18static int scsi_dev_type_suspend(struct device *dev, pm_message_t msg)
19{
20 struct device_driver *drv;
21 int err;
22
23 err = scsi_device_quiesce(to_scsi_device(dev));
24 if (err == 0) {
25 drv = dev->driver;
26 if (drv && drv->suspend)
27 err = drv->suspend(dev, msg);
28 }
29 dev_dbg(dev, "scsi suspend: %d\n", err);
30 return err;
31}
32
33static int scsi_dev_type_resume(struct device *dev)
34{
35 struct device_driver *drv;
36 int err = 0;
37
38 drv = dev->driver;
39 if (drv && drv->resume)
40 err = drv->resume(dev);
41 scsi_device_resume(to_scsi_device(dev));
42 dev_dbg(dev, "scsi resume: %d\n", err);
43 return err;
44}
45
46#ifdef CONFIG_PM_SLEEP
47
48static int scsi_bus_suspend_common(struct device *dev, pm_message_t msg)
49{
50 int err = 0;
51
52 if (scsi_is_sdev_device(dev))
53 err = scsi_dev_type_suspend(dev, msg);
54 return err;
55}
56
57static int scsi_bus_resume_common(struct device *dev)
58{
59 int err = 0;
60
61 if (scsi_is_sdev_device(dev))
62 err = scsi_dev_type_resume(dev);
63
64 if (err == 0) {
65 pm_runtime_disable(dev);
66 pm_runtime_set_active(dev);
67 pm_runtime_enable(dev);
68 }
69 return err;
70}
71
72static int scsi_bus_suspend(struct device *dev)
73{
74 return scsi_bus_suspend_common(dev, PMSG_SUSPEND);
75}
76
77static int scsi_bus_freeze(struct device *dev)
78{
79 return scsi_bus_suspend_common(dev, PMSG_FREEZE);
80}
81
82static int scsi_bus_poweroff(struct device *dev)
83{
84 return scsi_bus_suspend_common(dev, PMSG_HIBERNATE);
85}
86
87#else /* CONFIG_PM_SLEEP */
88
89#define scsi_bus_resume_common NULL
90#define scsi_bus_suspend NULL
91#define scsi_bus_freeze NULL
92#define scsi_bus_poweroff NULL
93
94#endif /* CONFIG_PM_SLEEP */
95
96#ifdef CONFIG_PM_RUNTIME
97
98static int scsi_runtime_suspend(struct device *dev)
99{
100 int err = 0;
101
102 dev_dbg(dev, "scsi_runtime_suspend\n");
103 if (scsi_is_sdev_device(dev)) {
104 err = scsi_dev_type_suspend(dev, PMSG_AUTO_SUSPEND);
105 if (err == -EAGAIN)
106 pm_schedule_suspend(dev, jiffies_to_msecs(
107 round_jiffies_up_relative(HZ/10)));
108 }
109
110 /* Insert hooks here for targets, hosts, and transport classes */
111
112 return err;
113}
114
115static int scsi_runtime_resume(struct device *dev)
116{
117 int err = 0;
118
119 dev_dbg(dev, "scsi_runtime_resume\n");
120 if (scsi_is_sdev_device(dev))
121 err = scsi_dev_type_resume(dev);
122
123 /* Insert hooks here for targets, hosts, and transport classes */
124
125 return err;
126}
127
128static int scsi_runtime_idle(struct device *dev)
129{
130 int err;
131
132 dev_dbg(dev, "scsi_runtime_idle\n");
133
134 /* Insert hooks here for targets, hosts, and transport classes */
135
136 if (scsi_is_sdev_device(dev))
137 err = pm_schedule_suspend(dev, 100);
138 else
139 err = pm_runtime_suspend(dev);
140 return err;
141}
142
143int scsi_autopm_get_device(struct scsi_device *sdev)
144{
145 int err;
146
147 err = pm_runtime_get_sync(&sdev->sdev_gendev);
148 if (err < 0 && err !=-EACCES)
149 pm_runtime_put_sync(&sdev->sdev_gendev);
150 else
151 err = 0;
152 return err;
153}
154EXPORT_SYMBOL_GPL(scsi_autopm_get_device);
155
156void scsi_autopm_put_device(struct scsi_device *sdev)
157{
158 pm_runtime_put_sync(&sdev->sdev_gendev);
159}
160EXPORT_SYMBOL_GPL(scsi_autopm_put_device);
161
162void scsi_autopm_get_target(struct scsi_target *starget)
163{
164 pm_runtime_get_sync(&starget->dev);
165}
166
167void scsi_autopm_put_target(struct scsi_target *starget)
168{
169 pm_runtime_put_sync(&starget->dev);
170}
171
172int scsi_autopm_get_host(struct Scsi_Host *shost)
173{
174 int err;
175
176 err = pm_runtime_get_sync(&shost->shost_gendev);
177 if (err < 0 && err !=-EACCES)
178 pm_runtime_put_sync(&shost->shost_gendev);
179 else
180 err = 0;
181 return err;
182}
183
184void scsi_autopm_put_host(struct Scsi_Host *shost)
185{
186 pm_runtime_put_sync(&shost->shost_gendev);
187}
188
189#else
190
191#define scsi_runtime_suspend NULL
192#define scsi_runtime_resume NULL
193#define scsi_runtime_idle NULL
194
195#endif /* CONFIG_PM_RUNTIME */
196
197const struct dev_pm_ops scsi_bus_pm_ops = {
198 .suspend = scsi_bus_suspend,
199 .resume = scsi_bus_resume_common,
200 .freeze = scsi_bus_freeze,
201 .thaw = scsi_bus_resume_common,
202 .poweroff = scsi_bus_poweroff,
203 .restore = scsi_bus_resume_common,
204 .runtime_suspend = scsi_runtime_suspend,
205 .runtime_resume = scsi_runtime_resume,
206 .runtime_idle = scsi_runtime_idle,
207};