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 10#include <scsi/scsi.h> 11#include <scsi/scsi_device.h> 12#include <scsi/scsi_driver.h> 13#include <scsi/scsi_host.h> 14 15#include "scsi_priv.h" 16 17static int scsi_dev_type_suspend(struct device *dev, pm_message_t msg) 18{ 19 struct device_driver *drv; 20 int err; 21 22 err = scsi_device_quiesce(to_scsi_device(dev)); 23 if (err == 0) { 24 drv = dev->driver; 25 if (drv && drv->suspend) 26 err = drv->suspend(dev, msg); 27 } 28 dev_dbg(dev, "scsi suspend: %d\n", err); 29 return err; 30} 31 32static int scsi_dev_type_resume(struct device *dev) 33{ 34 struct device_driver *drv; 35 int err = 0; 36 37 drv = dev->driver; 38 if (drv && drv->resume) 39 err = drv->resume(dev); 40 scsi_device_resume(to_scsi_device(dev)); 41 dev_dbg(dev, "scsi resume: %d\n", err); 42 return err; 43} 44 45#ifdef CONFIG_PM_SLEEP 46 47static int scsi_bus_suspend_common(struct device *dev, pm_message_t msg) 48{ 49 int err = 0; 50 51 if (scsi_is_sdev_device(dev)) 52 err = scsi_dev_type_suspend(dev, msg); 53 return err; 54} 55 56static int scsi_bus_resume_common(struct device *dev) 57{ 58 int err = 0; 59 60 if (scsi_is_sdev_device(dev)) 61 err = scsi_dev_type_resume(dev); 62 63 if (err == 0) { 64 pm_runtime_disable(dev); 65 pm_runtime_set_active(dev); 66 pm_runtime_enable(dev); 67 } 68 return err; 69} 70 71static int scsi_bus_suspend(struct device *dev) 72{ 73 return scsi_bus_suspend_common(dev, PMSG_SUSPEND); 74} 75 76static int scsi_bus_freeze(struct device *dev) 77{ 78 return scsi_bus_suspend_common(dev, PMSG_FREEZE); 79} 80 81static int scsi_bus_poweroff(struct device *dev) 82{ 83 return scsi_bus_suspend_common(dev, PMSG_HIBERNATE); 84} 85 86#else /* CONFIG_PM_SLEEP */ 87 88#define scsi_bus_resume_common NULL 89#define scsi_bus_suspend NULL 90#define scsi_bus_freeze NULL 91#define scsi_bus_poweroff NULL 92 93#endif /* CONFIG_PM_SLEEP */ 94 95#ifdef CONFIG_PM_RUNTIME 96 97static int scsi_runtime_suspend(struct device *dev) 98{ 99 int err = 0; 100 101 dev_dbg(dev, "scsi_runtime_suspend\n"); 102 if (scsi_is_sdev_device(dev)) { 103 err = scsi_dev_type_suspend(dev, PMSG_AUTO_SUSPEND); 104 if (err == -EAGAIN) 105 pm_schedule_suspend(dev, jiffies_to_msecs( 106 round_jiffies_up_relative(HZ/10))); 107 } 108 109 /* Insert hooks here for targets, hosts, and transport classes */ 110 111 return err; 112} 113 114static int scsi_runtime_resume(struct device *dev) 115{ 116 int err = 0; 117 118 dev_dbg(dev, "scsi_runtime_resume\n"); 119 if (scsi_is_sdev_device(dev)) 120 err = scsi_dev_type_resume(dev); 121 122 /* Insert hooks here for targets, hosts, and transport classes */ 123 124 return err; 125} 126 127static int scsi_runtime_idle(struct device *dev) 128{ 129 int err; 130 131 dev_dbg(dev, "scsi_runtime_idle\n"); 132 133 /* Insert hooks here for targets, hosts, and transport classes */ 134 135 if (scsi_is_sdev_device(dev)) 136 err = pm_schedule_suspend(dev, 100); 137 else 138 err = pm_runtime_suspend(dev); 139 return err; 140} 141 142int scsi_autopm_get_device(struct scsi_device *sdev) 143{ 144 int err; 145 146 err = pm_runtime_get_sync(&sdev->sdev_gendev); 147 if (err < 0) 148 pm_runtime_put_sync(&sdev->sdev_gendev); 149 else if (err > 0) 150 err = 0; 151 return err; 152} 153EXPORT_SYMBOL_GPL(scsi_autopm_get_device); 154 155void scsi_autopm_put_device(struct scsi_device *sdev) 156{ 157 pm_runtime_put_sync(&sdev->sdev_gendev); 158} 159EXPORT_SYMBOL_GPL(scsi_autopm_put_device); 160 161void scsi_autopm_get_target(struct scsi_target *starget) 162{ 163 pm_runtime_get_sync(&starget->dev); 164} 165 166void scsi_autopm_put_target(struct scsi_target *starget) 167{ 168 pm_runtime_put_sync(&starget->dev); 169} 170 171int scsi_autopm_get_host(struct Scsi_Host *shost) 172{ 173 int err; 174 175 err = pm_runtime_get_sync(&shost->shost_gendev); 176 if (err < 0) 177 pm_runtime_put_sync(&shost->shost_gendev); 178 else if (err > 0) 179 err = 0; 180 return err; 181} 182 183void scsi_autopm_put_host(struct Scsi_Host *shost) 184{ 185 pm_runtime_put_sync(&shost->shost_gendev); 186} 187 188#else 189 190#define scsi_runtime_suspend NULL 191#define scsi_runtime_resume NULL 192#define scsi_runtime_idle NULL 193 194#endif /* CONFIG_PM_RUNTIME */ 195 196const struct dev_pm_ops scsi_bus_pm_ops = { 197 .suspend = scsi_bus_suspend, 198 .resume = scsi_bus_resume_common, 199 .freeze = scsi_bus_freeze, 200 .thaw = scsi_bus_resume_common, 201 .poweroff = scsi_bus_poweroff, 202 .restore = scsi_bus_resume_common, 203 .runtime_suspend = scsi_runtime_suspend, 204 .runtime_resume = scsi_runtime_resume, 205 .runtime_idle = scsi_runtime_idle, 206}; 207