summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/scsi_pm.c
blob: af4c050ce6e4e96179f586aae4c54690229b9705 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
/*
 *	scsi_pm.c	Copyright (C) 2010 Alan Stern
 *
 *	SCSI dynamic Power Management
 *		Initial version: Alan Stern <stern@rowland.harvard.edu>
 */

#include <linux/pm_runtime.h>
#include <linux/export.h>
#include <linux/async.h>

#include <scsi/scsi.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_driver.h>
#include <scsi/scsi_host.h>

#include "scsi_priv.h"

static int scsi_dev_type_suspend(struct device *dev, int (*cb)(struct device *))
{
	int err;

	err = scsi_device_quiesce(to_scsi_device(dev));
	if (err == 0) {
		if (cb) {
			err = cb(dev);
			if (err)
				scsi_device_resume(to_scsi_device(dev));
		}
	}
	dev_dbg(dev, "scsi suspend: %d\n", err);
	return err;
}

static int scsi_dev_type_resume(struct device *dev, int (*cb)(struct device *))
{
	int err = 0;

	if (cb)
		err = cb(dev);
	scsi_device_resume(to_scsi_device(dev));
	dev_dbg(dev, "scsi resume: %d\n", err);
	return err;
}

#ifdef CONFIG_PM_SLEEP

static int
scsi_bus_suspend_common(struct device *dev, int (*cb)(struct device *))
{
	int err = 0;

	if (scsi_is_sdev_device(dev)) {
		/*
		 * All the high-level SCSI drivers that implement runtime
		 * PM treat runtime suspend, system suspend, and system
		 * hibernate nearly identically. In all cases the requirements
		 * for runtime suspension are stricter.
		 */
		if (pm_runtime_suspended(dev))
			return 0;

		err = scsi_dev_type_suspend(dev, cb);
	}

	return err;
}

static int
scsi_bus_resume_common(struct device *dev, int (*cb)(struct device *))
{
	int err = 0;

	if (scsi_is_sdev_device(dev))
		err = scsi_dev_type_resume(dev, cb);

	if (err == 0) {
		pm_runtime_disable(dev);
		pm_runtime_set_active(dev);
		pm_runtime_enable(dev);
	}
	return err;
}

static int scsi_bus_prepare(struct device *dev)
{
	if (scsi_is_sdev_device(dev)) {
		/* sd probing uses async_schedule.  Wait until it finishes. */
		async_synchronize_full_domain(&scsi_sd_probe_domain);

	} else if (scsi_is_host_device(dev)) {
		/* Wait until async scanning is finished */
		scsi_complete_async_scans();
	}
	return 0;
}

static int scsi_bus_suspend(struct device *dev)
{
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	return scsi_bus_suspend_common(dev, pm ? pm->suspend : NULL);
}

static int scsi_bus_resume(struct device *dev)
{
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	return scsi_bus_resume_common(dev, pm ? pm->resume : NULL);
}

static int scsi_bus_freeze(struct device *dev)
{
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	return scsi_bus_suspend_common(dev, pm ? pm->freeze : NULL);
}

static int scsi_bus_thaw(struct device *dev)
{
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	return scsi_bus_resume_common(dev, pm ? pm->thaw : NULL);
}

static int scsi_bus_poweroff(struct device *dev)
{
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	return scsi_bus_suspend_common(dev, pm ? pm->poweroff : NULL);
}

static int scsi_bus_restore(struct device *dev)
{
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	return scsi_bus_resume_common(dev, pm ? pm->restore : NULL);
}

#else /* CONFIG_PM_SLEEP */

#define scsi_bus_prepare		NULL
#define scsi_bus_suspend		NULL
#define scsi_bus_resume			NULL
#define scsi_bus_freeze			NULL
#define scsi_bus_thaw			NULL
#define scsi_bus_poweroff		NULL
#define scsi_bus_restore		NULL

#endif /* CONFIG_PM_SLEEP */

#ifdef CONFIG_PM_RUNTIME

static int sdev_blk_runtime_suspend(struct scsi_device *sdev,
					int (*cb)(struct device *))
{
	int err;

	err = blk_pre_runtime_suspend(sdev->request_queue);
	if (err)
		return err;
	if (cb)
		err = cb(&sdev->sdev_gendev);
	blk_post_runtime_suspend(sdev->request_queue, err);

	return err;
}

static int sdev_runtime_suspend(struct device *dev)
{
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	int (*cb)(struct device *) = pm ? pm->runtime_suspend : NULL;
	struct scsi_device *sdev = to_scsi_device(dev);
	int err;

	if (sdev->request_queue->dev)
		return sdev_blk_runtime_suspend(sdev, cb);

	err = scsi_dev_type_suspend(dev, cb);
	if (err == -EAGAIN)
		pm_schedule_suspend(dev, jiffies_to_msecs(
					round_jiffies_up_relative(HZ/10)));
	return err;
}

static int scsi_runtime_suspend(struct device *dev)
{
	int err = 0;

	dev_dbg(dev, "scsi_runtime_suspend\n");
	if (scsi_is_sdev_device(dev))
		err = sdev_runtime_suspend(dev);

	/* Insert hooks here for targets, hosts, and transport classes */

	return err;
}

static int sdev_blk_runtime_resume(struct scsi_device *sdev,
					int (*cb)(struct device *))
{
	int err = 0;

	blk_pre_runtime_resume(sdev->request_queue);
	if (cb)
		err = cb(&sdev->sdev_gendev);
	blk_post_runtime_resume(sdev->request_queue, err);

	return err;
}

static int sdev_runtime_resume(struct device *dev)
{
	struct scsi_device *sdev = to_scsi_device(dev);
	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
	int (*cb)(struct device *) = pm ? pm->runtime_resume : NULL;

	if (sdev->request_queue->dev)
		return sdev_blk_runtime_resume(sdev, cb);
	else
		return scsi_dev_type_resume(dev, cb);
}

static int scsi_runtime_resume(struct device *dev)
{
	int err = 0;

	dev_dbg(dev, "scsi_runtime_resume\n");
	if (scsi_is_sdev_device(dev))
		err = sdev_runtime_resume(dev);

	/* Insert hooks here for targets, hosts, and transport classes */

	return err;
}

static int scsi_runtime_idle(struct device *dev)
{
	dev_dbg(dev, "scsi_runtime_idle\n");

	/* Insert hooks here for targets, hosts, and transport classes */

	if (scsi_is_sdev_device(dev)) {
		struct scsi_device *sdev = to_scsi_device(dev);

		if (sdev->request_queue->dev) {
			pm_runtime_mark_last_busy(dev);
			pm_runtime_autosuspend(dev);
			return -EBUSY;
		}
	}
	return 0;
}

int scsi_autopm_get_device(struct scsi_device *sdev)
{
	int	err;

	err = pm_runtime_get_sync(&sdev->sdev_gendev);
	if (err < 0 && err !=-EACCES)
		pm_runtime_put_sync(&sdev->sdev_gendev);
	else
		err = 0;
	return err;
}
EXPORT_SYMBOL_GPL(scsi_autopm_get_device);

void scsi_autopm_put_device(struct scsi_device *sdev)
{
	pm_runtime_put_sync(&sdev->sdev_gendev);
}
EXPORT_SYMBOL_GPL(scsi_autopm_put_device);

void scsi_autopm_get_target(struct scsi_target *starget)
{
	pm_runtime_get_sync(&starget->dev);
}

void scsi_autopm_put_target(struct scsi_target *starget)
{
	pm_runtime_put_sync(&starget->dev);
}

int scsi_autopm_get_host(struct Scsi_Host *shost)
{
	int	err;

	err = pm_runtime_get_sync(&shost->shost_gendev);
	if (err < 0 && err !=-EACCES)
		pm_runtime_put_sync(&shost->shost_gendev);
	else
		err = 0;
	return err;
}

void scsi_autopm_put_host(struct Scsi_Host *shost)
{
	pm_runtime_put_sync(&shost->shost_gendev);
}

#else

#define scsi_runtime_suspend	NULL
#define scsi_runtime_resume	NULL
#define scsi_runtime_idle	NULL

#endif /* CONFIG_PM_RUNTIME */

const struct dev_pm_ops scsi_bus_pm_ops = {
	.prepare =		scsi_bus_prepare,
	.suspend =		scsi_bus_suspend,
	.resume =		scsi_bus_resume,
	.freeze =		scsi_bus_freeze,
	.thaw =			scsi_bus_thaw,
	.poweroff =		scsi_bus_poweroff,
	.restore =		scsi_bus_restore,
	.runtime_suspend =	scsi_runtime_suspend,
	.runtime_resume =	scsi_runtime_resume,
	.runtime_idle =		scsi_runtime_idle,
};
OpenPOWER on IntegriCloud