diff options
Diffstat (limited to 'drivers/scsi/scsi_pm.c')
| -rw-r--r-- | drivers/scsi/scsi_pm.c | 273 |
1 files changed, 273 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c new file mode 100644 index 000000000..d581613d8 --- /dev/null +++ b/drivers/scsi/scsi_pm.c @@ -0,0 +1,273 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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/blk-pm.h> + +#include <scsi/scsi.h> +#include <scsi/scsi_device.h> +#include <scsi/scsi_driver.h> +#include <scsi/scsi_host.h> + +#include "scsi_priv.h" + +#ifdef CONFIG_PM_SLEEP + +static int do_scsi_suspend(struct device *dev, const struct dev_pm_ops *pm) +{ + return pm && pm->suspend ? pm->suspend(dev) : 0; +} + +static int do_scsi_freeze(struct device *dev, const struct dev_pm_ops *pm) +{ + return pm && pm->freeze ? pm->freeze(dev) : 0; +} + +static int do_scsi_poweroff(struct device *dev, const struct dev_pm_ops *pm) +{ + return pm && pm->poweroff ? pm->poweroff(dev) : 0; +} + +static int do_scsi_resume(struct device *dev, const struct dev_pm_ops *pm) +{ + return pm && pm->resume ? pm->resume(dev) : 0; +} + +static int do_scsi_thaw(struct device *dev, const struct dev_pm_ops *pm) +{ + return pm && pm->thaw ? pm->thaw(dev) : 0; +} + +static int do_scsi_restore(struct device *dev, const struct dev_pm_ops *pm) +{ + return pm && pm->restore ? pm->restore(dev) : 0; +} + +static int scsi_dev_type_suspend(struct device *dev, + int (*cb)(struct device *, const struct dev_pm_ops *)) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int err; + + err = scsi_device_quiesce(to_scsi_device(dev)); + if (err == 0) { + err = cb(dev, pm); + if (err) + scsi_device_resume(to_scsi_device(dev)); + } + dev_dbg(dev, "scsi suspend: %d\n", err); + return err; +} + +static int +scsi_bus_suspend_common(struct device *dev, + int (*cb)(struct device *, const struct dev_pm_ops *)) +{ + if (!scsi_is_sdev_device(dev)) + return 0; + + return scsi_dev_type_suspend(dev, cb); +} + +static int scsi_bus_resume_common(struct device *dev, + int (*cb)(struct device *, const struct dev_pm_ops *)) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int err; + + if (!scsi_is_sdev_device(dev)) + return 0; + + err = cb(dev, pm); + scsi_device_resume(to_scsi_device(dev)); + dev_dbg(dev, "scsi resume: %d\n", err); + + return err; +} + +static int scsi_bus_prepare(struct device *dev) +{ + 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) +{ + return scsi_bus_suspend_common(dev, do_scsi_suspend); +} + +static int scsi_bus_resume(struct device *dev) +{ + return scsi_bus_resume_common(dev, do_scsi_resume); +} + +static int scsi_bus_freeze(struct device *dev) +{ + return scsi_bus_suspend_common(dev, do_scsi_freeze); +} + +static int scsi_bus_thaw(struct device *dev) +{ + return scsi_bus_resume_common(dev, do_scsi_thaw); +} + +static int scsi_bus_poweroff(struct device *dev) +{ + return scsi_bus_suspend_common(dev, do_scsi_poweroff); +} + +static int scsi_bus_restore(struct device *dev) +{ + return scsi_bus_resume_common(dev, do_scsi_restore); +} + +#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 */ + +static int sdev_runtime_suspend(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + struct scsi_device *sdev = to_scsi_device(dev); + int err = 0; + + err = blk_pre_runtime_suspend(sdev->request_queue); + if (err) + return err; + if (pm && pm->runtime_suspend) + err = pm->runtime_suspend(dev); + blk_post_runtime_suspend(sdev->request_queue, err); + + 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_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 err = 0; + + blk_pre_runtime_resume(sdev->request_queue); + if (pm && pm->runtime_resume) + err = pm->runtime_resume(dev); + blk_post_runtime_resume(sdev->request_queue); + + return err; +} + +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)) { + 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); +} + +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, +}; |