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 22 static 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 27 static 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 32 static 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 37 static 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 42 static 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 47 static 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 52 static 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 68 static int 69 scsi_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 78 static 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 94 static 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 } 102 103 static int scsi_bus_suspend(struct device *dev) 104 { 105 return scsi_bus_suspend_common(dev, do_scsi_suspend); 106 } 107 108 static int scsi_bus_resume(struct device *dev) 109 { 110 return scsi_bus_resume_common(dev, do_scsi_resume); 111 } 112 113 static int scsi_bus_freeze(struct device *dev) 114 { 115 return scsi_bus_suspend_common(dev, do_scsi_freeze); 116 } 117 118 static int scsi_bus_thaw(struct device *dev) 119 { 120 return scsi_bus_resume_common(dev, do_scsi_thaw); 121 } 122 123 static int scsi_bus_poweroff(struct device *dev) 124 { 125 return scsi_bus_suspend_common(dev, do_scsi_poweroff); 126 } 127 128 static int scsi_bus_restore(struct device *dev) 129 { 130 return scsi_bus_resume_common(dev, 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 */ 144 145 static 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(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(sdev->request_queue, err); 157 158 return err; 159 } 160 161 static 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 } 173 174 static 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(sdev->request_queue); 181 if (pm && pm->runtime_resume) 182 err = pm->runtime_resume(dev); 183 blk_post_runtime_resume(sdev->request_queue); 184 185 return err; 186 } 187 188 static 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 } 200 201 static 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 } 215 216 int scsi_autopm_get_device(struct scsi_device *sdev) 217 { 218 int err; 219 220 err = pm_runtime_get_sync(&sdev->sdev_gendev); 221 if (err < 0 && err !=-EACCES) 222 pm_runtime_put_sync(&sdev->sdev_gendev); 223 else 224 err = 0; 225 return err; 226 } 227 EXPORT_SYMBOL_GPL(scsi_autopm_get_device); 228 229 void scsi_autopm_put_device(struct scsi_device *sdev) 230 { 231 pm_runtime_put_sync(&sdev->sdev_gendev); 232 } 233 EXPORT_SYMBOL_GPL(scsi_autopm_put_device); 234 235 void scsi_autopm_get_target(struct scsi_target *starget) 236 { 237 pm_runtime_get_sync(&starget->dev); 238 } 239 240 void scsi_autopm_put_target(struct scsi_target *starget) 241 { 242 pm_runtime_put_sync(&starget->dev); 243 } 244 245 int scsi_autopm_get_host(struct Scsi_Host *shost) 246 { 247 int err; 248 249 err = pm_runtime_get_sync(&shost->shost_gendev); 250 if (err < 0 && err !=-EACCES) 251 pm_runtime_put_sync(&shost->shost_gendev); 252 else 253 err = 0; 254 return err; 255 } 256 257 void scsi_autopm_put_host(struct Scsi_Host *shost) 258 { 259 pm_runtime_put_sync(&shost->shost_gendev); 260 } 261 262 const 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