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 18 static 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 33 static 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 48 static 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 57 static 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 72 static int scsi_bus_suspend(struct device *dev) 73 { 74 return scsi_bus_suspend_common(dev, PMSG_SUSPEND); 75 } 76 77 static int scsi_bus_freeze(struct device *dev) 78 { 79 return scsi_bus_suspend_common(dev, PMSG_FREEZE); 80 } 81 82 static 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 98 static 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 } 114 115 static 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 } 127 128 static 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 } 142 143 int 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 } 154 EXPORT_SYMBOL_GPL(scsi_autopm_get_device); 155 156 void scsi_autopm_put_device(struct scsi_device *sdev) 157 { 158 pm_runtime_put_sync(&sdev->sdev_gendev); 159 } 160 EXPORT_SYMBOL_GPL(scsi_autopm_put_device); 161 162 void scsi_autopm_get_target(struct scsi_target *starget) 163 { 164 pm_runtime_get_sync(&starget->dev); 165 } 166 167 void scsi_autopm_put_target(struct scsi_target *starget) 168 { 169 pm_runtime_put_sync(&starget->dev); 170 } 171 172 int 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 } 183 184 void 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 */ 196 197 const 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 }; 208