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/async.h> 12 #include <linux/blk-pm.h> 13 14 #include <scsi/scsi.h> 15 #include <scsi/scsi_device.h> 16 #include <scsi/scsi_driver.h> 17 #include <scsi/scsi_host.h> 18 19 #include "scsi_priv.h" 20 21 #ifdef CONFIG_PM_SLEEP 22 23 static int do_scsi_suspend(struct device *dev, const struct dev_pm_ops *pm) 24 { 25 return pm && pm->suspend ? pm->suspend(dev) : 0; 26 } 27 28 static int do_scsi_freeze(struct device *dev, const struct dev_pm_ops *pm) 29 { 30 return pm && pm->freeze ? pm->freeze(dev) : 0; 31 } 32 33 static int do_scsi_poweroff(struct device *dev, const struct dev_pm_ops *pm) 34 { 35 return pm && pm->poweroff ? pm->poweroff(dev) : 0; 36 } 37 38 static int do_scsi_resume(struct device *dev, const struct dev_pm_ops *pm) 39 { 40 return pm && pm->resume ? pm->resume(dev) : 0; 41 } 42 43 static int do_scsi_thaw(struct device *dev, const struct dev_pm_ops *pm) 44 { 45 return pm && pm->thaw ? pm->thaw(dev) : 0; 46 } 47 48 static int do_scsi_restore(struct device *dev, const struct dev_pm_ops *pm) 49 { 50 return pm && pm->restore ? pm->restore(dev) : 0; 51 } 52 53 static int scsi_dev_type_suspend(struct device *dev, 54 int (*cb)(struct device *, const struct dev_pm_ops *)) 55 { 56 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; 57 int err; 58 59 err = scsi_device_quiesce(to_scsi_device(dev)); 60 if (err == 0) { 61 err = cb(dev, pm); 62 if (err) 63 scsi_device_resume(to_scsi_device(dev)); 64 } 65 dev_dbg(dev, "scsi suspend: %d\n", err); 66 return err; 67 } 68 69 static int 70 scsi_bus_suspend_common(struct device *dev, 71 int (*cb)(struct device *, const struct dev_pm_ops *)) 72 { 73 if (!scsi_is_sdev_device(dev)) 74 return 0; 75 76 return scsi_dev_type_suspend(dev, cb); 77 } 78 79 static int scsi_bus_resume_common(struct device *dev, 80 int (*cb)(struct device *, const struct dev_pm_ops *)) 81 { 82 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; 83 int err; 84 85 if (!scsi_is_sdev_device(dev)) 86 return 0; 87 88 err = cb(dev, pm); 89 scsi_device_resume(to_scsi_device(dev)); 90 dev_dbg(dev, "scsi resume: %d\n", err); 91 92 return err; 93 } 94 95 static int scsi_bus_prepare(struct device *dev) 96 { 97 if (scsi_is_host_device(dev)) { 98 /* Wait until async scanning is finished */ 99 scsi_complete_async_scans(); 100 } 101 return 0; 102 } 103 104 static int scsi_bus_suspend(struct device *dev) 105 { 106 return scsi_bus_suspend_common(dev, do_scsi_suspend); 107 } 108 109 static int scsi_bus_resume(struct device *dev) 110 { 111 return scsi_bus_resume_common(dev, do_scsi_resume); 112 } 113 114 static int scsi_bus_freeze(struct device *dev) 115 { 116 return scsi_bus_suspend_common(dev, do_scsi_freeze); 117 } 118 119 static int scsi_bus_thaw(struct device *dev) 120 { 121 return scsi_bus_resume_common(dev, do_scsi_thaw); 122 } 123 124 static int scsi_bus_poweroff(struct device *dev) 125 { 126 return scsi_bus_suspend_common(dev, do_scsi_poweroff); 127 } 128 129 static int scsi_bus_restore(struct device *dev) 130 { 131 return scsi_bus_resume_common(dev, do_scsi_restore); 132 } 133 134 #else /* CONFIG_PM_SLEEP */ 135 136 #define scsi_bus_prepare NULL 137 #define scsi_bus_suspend NULL 138 #define scsi_bus_resume NULL 139 #define scsi_bus_freeze NULL 140 #define scsi_bus_thaw NULL 141 #define scsi_bus_poweroff NULL 142 #define scsi_bus_restore NULL 143 144 #endif /* CONFIG_PM_SLEEP */ 145 146 static int sdev_runtime_suspend(struct device *dev) 147 { 148 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; 149 struct scsi_device *sdev = to_scsi_device(dev); 150 int err = 0; 151 152 err = blk_pre_runtime_suspend(sdev->request_queue); 153 if (err) 154 return err; 155 if (pm && pm->runtime_suspend) 156 err = pm->runtime_suspend(dev); 157 blk_post_runtime_suspend(sdev->request_queue, err); 158 159 return err; 160 } 161 162 static int scsi_runtime_suspend(struct device *dev) 163 { 164 int err = 0; 165 166 dev_dbg(dev, "scsi_runtime_suspend\n"); 167 if (scsi_is_sdev_device(dev)) 168 err = sdev_runtime_suspend(dev); 169 170 /* Insert hooks here for targets, hosts, and transport classes */ 171 172 return err; 173 } 174 175 static int sdev_runtime_resume(struct device *dev) 176 { 177 struct scsi_device *sdev = to_scsi_device(dev); 178 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; 179 int err = 0; 180 181 blk_pre_runtime_resume(sdev->request_queue); 182 if (pm && pm->runtime_resume) 183 err = pm->runtime_resume(dev); 184 blk_post_runtime_resume(sdev->request_queue, err); 185 186 return err; 187 } 188 189 static int scsi_runtime_resume(struct device *dev) 190 { 191 int err = 0; 192 193 dev_dbg(dev, "scsi_runtime_resume\n"); 194 if (scsi_is_sdev_device(dev)) 195 err = sdev_runtime_resume(dev); 196 197 /* Insert hooks here for targets, hosts, and transport classes */ 198 199 return err; 200 } 201 202 static int scsi_runtime_idle(struct device *dev) 203 { 204 dev_dbg(dev, "scsi_runtime_idle\n"); 205 206 /* Insert hooks here for targets, hosts, and transport classes */ 207 208 if (scsi_is_sdev_device(dev)) { 209 pm_runtime_mark_last_busy(dev); 210 pm_runtime_autosuspend(dev); 211 return -EBUSY; 212 } 213 214 return 0; 215 } 216 217 int scsi_autopm_get_device(struct scsi_device *sdev) 218 { 219 int err; 220 221 err = pm_runtime_get_sync(&sdev->sdev_gendev); 222 if (err < 0 && err !=-EACCES) 223 pm_runtime_put_sync(&sdev->sdev_gendev); 224 else 225 err = 0; 226 return err; 227 } 228 EXPORT_SYMBOL_GPL(scsi_autopm_get_device); 229 230 void scsi_autopm_put_device(struct scsi_device *sdev) 231 { 232 pm_runtime_put_sync(&sdev->sdev_gendev); 233 } 234 EXPORT_SYMBOL_GPL(scsi_autopm_put_device); 235 236 void scsi_autopm_get_target(struct scsi_target *starget) 237 { 238 pm_runtime_get_sync(&starget->dev); 239 } 240 241 void scsi_autopm_put_target(struct scsi_target *starget) 242 { 243 pm_runtime_put_sync(&starget->dev); 244 } 245 246 int scsi_autopm_get_host(struct Scsi_Host *shost) 247 { 248 int err; 249 250 err = pm_runtime_get_sync(&shost->shost_gendev); 251 if (err < 0 && err !=-EACCES) 252 pm_runtime_put_sync(&shost->shost_gendev); 253 else 254 err = 0; 255 return err; 256 } 257 258 void scsi_autopm_put_host(struct Scsi_Host *shost) 259 { 260 pm_runtime_put_sync(&shost->shost_gendev); 261 } 262 263 const struct dev_pm_ops scsi_bus_pm_ops = { 264 .prepare = scsi_bus_prepare, 265 .suspend = scsi_bus_suspend, 266 .resume = scsi_bus_resume, 267 .freeze = scsi_bus_freeze, 268 .thaw = scsi_bus_thaw, 269 .poweroff = scsi_bus_poweroff, 270 .restore = scsi_bus_restore, 271 .runtime_suspend = scsi_runtime_suspend, 272 .runtime_resume = scsi_runtime_resume, 273 .runtime_idle = scsi_runtime_idle, 274 }; 275