[PATCH v5 5/7] scsi: pm: add may_power_off flag
From: Aaron Lu <hidden>
Date: 2012-08-31 09:43:21
Also in:
linux-acpi, linux-scsi
Subsystem:
scsi subsystem, the rest · Maintainers:
"James E.J. Bottomley", "Martin K. Petersen", Linus Torvalds
Add a new flag may_power_off for scsi device, it gives the user a chance to control when the device is runtime suspended, can we remove its power if possible. And if the device can be powered off(reflected by can_power_off flag, determined by individual driver), create a sysfs entry named may_power_off to let user control the flag. I'm planning using this flag for sr and sd. Signed-off-by: Aaron Lu <redacted> --- drivers/scsi/scsi_sysfs.c | 10 ++++++---- include/scsi/scsi_device.h | 1 + 2 files changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 093d4f6..92ea17c 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c@@ -484,9 +484,6 @@ sdev_store_##field (struct device *dev, struct device_attribute *attr, \ } \ static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field); -/* Currently we don't export bit fields, but we might in future, - * so leave this code in */ -#if 0 /* * sdev_rd_attr: create a function and attribute variable for a * read/write bit field.
@@ -526,7 +523,7 @@ static int scsi_sdev_check_buf_bit(const char *buf) } else return -EINVAL; } -#endif + /* * Create the actual show/store functions and data structures. */
@@ -860,6 +857,8 @@ static struct device_attribute sdev_attr_queue_type_rw = __ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field, sdev_store_queue_type_rw); +sdev_rw_attr_bit (may_power_off); + /** * scsi_sysfs_add_sdev - add scsi device to sysfs * @sdev: scsi_device to add
@@ -950,6 +949,9 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev) } } + if (sdev->can_power_off) + device_create_file(&sdev->sdev_gendev, &dev_attr_may_power_off); + return error; }
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 72d946f..41cec7f 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h@@ -157,6 +157,7 @@ struct scsi_device { unsigned can_power_off:1; /* Device supports runtime power off */ unsigned wce_default_on:1; /* Cache is ON by default */ unsigned wakeup_by_user:1; /* User wakes up the device */ + unsigned may_power_off:1; /* Power off is allowed by user */ DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */ struct list_head event_list; /* asserted events */
--
1.7.11.5