1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * scsi_pm.c Copyright (C) 2010 Alan Stern
4 *
5 * SCSI dynamic Power Management
6 * Initial version: Alan Stern <stern@rowland.harvard.edu>
7 */
8
9#include <linux/pm_runtime.h>
10#include <linux/export.h>
11#include <linux/blk-pm.h>
12
13#include <scsi/scsi.h>
14#include <scsi/scsi_device.h>
15#include <scsi/scsi_driver.h>
16#include <scsi/scsi_host.h>
17
18#include "scsi_priv.h"
19
20#ifdef CONFIG_PM_SLEEP
21
22static int do_scsi_suspend(struct device *dev, const struct dev_pm_ops *pm)
23{
24 return pm && pm->suspend ? pm->suspend(dev) : 0;
25}
26
27static int do_scsi_freeze(struct device *dev, const struct dev_pm_ops *pm)
28{
29 return pm && pm->freeze ? pm->freeze(dev) : 0;
30}
31
32static int do_scsi_poweroff(struct device *dev, const struct dev_pm_ops *pm)
33{
34 return pm && pm->poweroff ? pm->poweroff(dev) : 0;
35}
36
37static int do_scsi_resume(struct device *dev, const struct dev_pm_ops *pm)
38{
39 return pm && pm->resume ? pm->resume(dev) : 0;
40}
41
42static int do_scsi_thaw(struct device *dev, const struct dev_pm_ops *pm)
43{
44 return pm && pm->thaw ? pm->thaw(dev) : 0;
45}
46
47static int do_scsi_restore(struct device *dev, const struct dev_pm_ops *pm)
48{
49 return pm && pm->restore ? pm->restore(dev) : 0;
50}
51
52static int scsi_dev_type_suspend(struct device *dev,
53 int (*cb)(struct device *, const struct dev_pm_ops *))
54{
55 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
56 int err;
57
58 err = scsi_device_quiesce(to_scsi_device(dev));
59 if (err == 0) {
60 err = cb(dev, pm);
61 if (err)
62 scsi_device_resume(to_scsi_device(dev));
63 }
64 dev_dbg(dev, "scsi suspend: %d\n", err);
65 return err;
66}
67
68static int
69scsi_bus_suspend_common(struct device *dev,
70 int (*cb)(struct device *, const struct dev_pm_ops *))
71{
72 if (!scsi_is_sdev_device(dev))
73 return 0;
74
75 return scsi_dev_type_suspend(dev, cb);
76}
77
78static int scsi_bus_resume_common(struct device *dev,
79 int (*cb)(struct device *, const struct dev_pm_ops *))
80{
81 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
82 int err;
83
84 if (!scsi_is_sdev_device(dev))
85 return 0;
86
87 err = cb(dev, pm);
88 scsi_device_resume(to_scsi_device(dev));
89 dev_dbg(dev, "scsi resume: %d\n", err);
90
91 return err;
92}
93
94static int scsi_bus_prepare(struct device *dev)
95{
96 if (scsi_is_host_device(dev)) {
97 /* Wait until async scanning is finished */
98 scsi_complete_async_scans();
99 }
100 return 0;
101}
102
103static int scsi_bus_suspend(struct device *dev)
104{
105 return scsi_bus_suspend_common(dev, cb: do_scsi_suspend);
106}
107
108static int scsi_bus_resume(struct device *dev)
109{
110 return scsi_bus_resume_common(dev, cb: do_scsi_resume);
111}
112
113static int scsi_bus_freeze(struct device *dev)
114{
115 return scsi_bus_suspend_common(dev, cb: do_scsi_freeze);
116}
117
118static int scsi_bus_thaw(struct device *dev)
119{
120 return scsi_bus_resume_common(dev, cb: do_scsi_thaw);
121}
122
123static int scsi_bus_poweroff(struct device *dev)
124{
125 return scsi_bus_suspend_common(dev, cb: do_scsi_poweroff);
126}
127
128static int scsi_bus_restore(struct device *dev)
129{
130 return scsi_bus_resume_common(dev, cb: do_scsi_restore);
131}
132
133#else /* CONFIG_PM_SLEEP */
134
135#define scsi_bus_prepare NULL
136#define scsi_bus_suspend NULL
137#define scsi_bus_resume NULL
138#define scsi_bus_freeze NULL
139#define scsi_bus_thaw NULL
140#define scsi_bus_poweroff NULL
141#define scsi_bus_restore NULL
142
143#endif /* CONFIG_PM_SLEEP */
144
145static int sdev_runtime_suspend(struct device *dev)
146{
147 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
148 struct scsi_device *sdev = to_scsi_device(dev);
149 int err = 0;
150
151 err = blk_pre_runtime_suspend(q: sdev->request_queue);
152 if (err)
153 return err;
154 if (pm && pm->runtime_suspend)
155 err = pm->runtime_suspend(dev);
156 blk_post_runtime_suspend(q: sdev->request_queue, err);
157
158 return err;
159}
160
161static int scsi_runtime_suspend(struct device *dev)
162{
163 int err = 0;
164
165 dev_dbg(dev, "scsi_runtime_suspend\n");
166 if (scsi_is_sdev_device(dev))
167 err = sdev_runtime_suspend(dev);
168
169 /* Insert hooks here for targets, hosts, and transport classes */
170
171 return err;
172}
173
174static int sdev_runtime_resume(struct device *dev)
175{
176 struct scsi_device *sdev = to_scsi_device(dev);
177 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
178 int err = 0;
179
180 blk_pre_runtime_resume(q: sdev->request_queue);
181 if (pm && pm->runtime_resume)
182 err = pm->runtime_resume(dev);
183 blk_post_runtime_resume(q: sdev->request_queue);
184
185 return err;
186}
187
188static int scsi_runtime_resume(struct device *dev)
189{
190 int err = 0;
191
192 dev_dbg(dev, "scsi_runtime_resume\n");
193 if (scsi_is_sdev_device(dev))
194 err = sdev_runtime_resume(dev);
195
196 /* Insert hooks here for targets, hosts, and transport classes */
197
198 return err;
199}
200
201static int scsi_runtime_idle(struct device *dev)
202{
203 dev_dbg(dev, "scsi_runtime_idle\n");
204
205 /* Insert hooks here for targets, hosts, and transport classes */
206
207 if (scsi_is_sdev_device(dev)) {
208 pm_runtime_mark_last_busy(dev);
209 pm_runtime_autosuspend(dev);
210 return -EBUSY;
211 }
212
213 return 0;
214}
215
216int scsi_autopm_get_device(struct scsi_device *sdev)
217{
218 int err;
219
220 err = pm_runtime_get_sync(dev: &sdev->sdev_gendev);
221 if (err < 0 && err !=-EACCES)
222 pm_runtime_put_sync(dev: &sdev->sdev_gendev);
223 else
224 err = 0;
225 return err;
226}
227EXPORT_SYMBOL_GPL(scsi_autopm_get_device);
228
229void scsi_autopm_put_device(struct scsi_device *sdev)
230{
231 pm_runtime_put_sync(dev: &sdev->sdev_gendev);
232}
233EXPORT_SYMBOL_GPL(scsi_autopm_put_device);
234
235void scsi_autopm_get_target(struct scsi_target *starget)
236{
237 pm_runtime_get_sync(dev: &starget->dev);
238}
239
240void scsi_autopm_put_target(struct scsi_target *starget)
241{
242 pm_runtime_put_sync(dev: &starget->dev);
243}
244
245int scsi_autopm_get_host(struct Scsi_Host *shost)
246{
247 int err;
248
249 err = pm_runtime_get_sync(dev: &shost->shost_gendev);
250 if (err < 0 && err !=-EACCES)
251 pm_runtime_put_sync(dev: &shost->shost_gendev);
252 else
253 err = 0;
254 return err;
255}
256
257void scsi_autopm_put_host(struct Scsi_Host *shost)
258{
259 pm_runtime_put_sync(dev: &shost->shost_gendev);
260}
261
262const struct dev_pm_ops scsi_bus_pm_ops = {
263 .prepare = scsi_bus_prepare,
264 .suspend = scsi_bus_suspend,
265 .resume = scsi_bus_resume,
266 .freeze = scsi_bus_freeze,
267 .thaw = scsi_bus_thaw,
268 .poweroff = scsi_bus_poweroff,
269 .restore = scsi_bus_restore,
270 .runtime_suspend = scsi_runtime_suspend,
271 .runtime_resume = scsi_runtime_resume,
272 .runtime_idle = scsi_runtime_idle,
273};
274