diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-usb | 26 | ||||
| -rw-r--r-- | drivers/usb/core/driver.c | 15 | ||||
| -rw-r--r-- | drivers/usb/core/quirks.c | 2 | ||||
| -rw-r--r-- | drivers/usb/core/sysfs.c | 81 | ||||
| -rw-r--r-- | include/linux/usb.h | 2 |
5 files changed, 118 insertions, 8 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb index 00a8432..f9937ad 100644 --- a/Documentation/ABI/testing/sysfs-bus-usb +++ b/Documentation/ABI/testing/sysfs-bus-usb @@ -13,3 +13,29 @@ Description: The autosuspend delay for newly-created devices is set to the value of the usbcore.autosuspend module parameter. + +What: /sys/bus/usb/devices/.../power/level +Date: March 2007 +KernelVersion: 2.6.21 +Contact: Alan Stern <stern@rowland.harvard.edu> +Description: + Each USB device directory will contain a file named + power/level. This file holds a power-level setting for + the device, one of "on", "auto", or "suspend". + + "on" means that the device is not allowed to autosuspend, + although normal suspends for system sleep will still + be honored. "auto" means the device will autosuspend + and autoresume in the usual manner, according to the + capabilities of its driver. "suspend" means the device + is forced into a suspended state and it will not autoresume + in response to I/O requests. However remote-wakeup requests + from the device may still be enabled (the remote-wakeup + setting is controlled separately by the power/wakeup + attribute). + + During normal use, devices should be left in the "auto" + level. The other levels are meant for administrative uses. + If you want to suspend a device immediately but leave it + free to wake up in response to I/O requests, you should + write "0" to power/autosuspend. diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 884179f..9b6a60f 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -872,8 +872,10 @@ static int usb_resume_device(struct usb_device *udev) done: // dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status); - if (status == 0) + if (status == 0) { + udev->autoresume_disabled = 0; udev->dev.power.power_state.event = PM_EVENT_ON; + } return status; } @@ -970,7 +972,7 @@ static int autosuspend_check(struct usb_device *udev) udev->do_remote_wakeup = device_may_wakeup(&udev->dev); if (udev->pm_usage_cnt > 0) return -EBUSY; - if (udev->autosuspend_delay < 0) + if (udev->autosuspend_delay < 0 || udev->autosuspend_disabled) return -EPERM; if (udev->actconfig) { @@ -1116,6 +1118,8 @@ static int usb_resume_both(struct usb_device *udev) struct usb_interface *intf; struct usb_device *parent = udev->parent; + if (udev->auto_pm && udev->autoresume_disabled) + return -EPERM; cancel_delayed_work(&udev->autosuspend); if (udev->state == USB_STATE_NOTATTACHED) return -ENODEV; @@ -1486,9 +1490,14 @@ static int usb_suspend(struct device *dev, pm_message_t message) static int usb_resume(struct device *dev) { + struct usb_device *udev; + if (!is_usb_device(dev)) /* Ignore PM for interfaces */ return 0; - return usb_external_resume_device(to_usb_device(dev)); + udev = to_usb_device(dev); + if (udev->autoresume_disabled) + return -EPERM; + return usb_external_resume_device(udev); } #else diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c index f08ec85..739f520 100644 --- a/drivers/usb/core/quirks.c +++ b/drivers/usb/core/quirks.c @@ -42,7 +42,7 @@ static void usb_autosuspend_quirk(struct usb_device *udev) { #ifdef CONFIG_USB_SUSPEND /* disable autosuspend, but allow the user to re-enable it via sysfs */ - udev->autosuspend_delay = 0; + udev->autosuspend_disabled = 1; #endif } diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c index 731001f..2ea47a3 100644 --- a/drivers/usb/core/sysfs.c +++ b/drivers/usb/core/sysfs.c @@ -11,6 +11,7 @@ #include <linux/kernel.h> +#include <linux/string.h> #include <linux/usb.h> #include "usb.h" @@ -184,9 +185,8 @@ set_autosuspend(struct device *dev, struct device_attribute *attr, if (value >= 0) usb_try_autosuspend_device(udev); else { - usb_lock_device(udev); - usb_external_resume_device(udev); - usb_unlock_device(udev); + if (usb_autoresume_device(udev) == 0) + usb_autosuspend_device(udev); } return count; } @@ -194,22 +194,95 @@ set_autosuspend(struct device *dev, struct device_attribute *attr, static DEVICE_ATTR(autosuspend, S_IRUGO | S_IWUSR, show_autosuspend, set_autosuspend); +static const char on_string[] = "on"; +static const char auto_string[] = "auto"; +static const char suspend_string[] = "suspend"; + +static ssize_t +show_level(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct usb_device *udev = to_usb_device(dev); + const char *p = auto_string; + + if (udev->state == USB_STATE_SUSPENDED) { + if (udev->autoresume_disabled) + p = suspend_string; + } else { + if (udev->autosuspend_disabled) + p = on_string; + } + return sprintf(buf, "%s\n", p); +} + +static ssize_t +set_level(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct usb_device *udev = to_usb_device(dev); + int len = count; + char *cp; + int rc = 0; + + cp = memchr(buf, '\n', count); + if (cp) + len = cp - buf; + + usb_lock_device(udev); + + /* Setting the flags without calling usb_pm_lock is a subject to + * races, but who cares... + */ + if (len == sizeof on_string - 1 && + strncmp(buf, on_string, len) == 0) { + udev->autosuspend_disabled = 1; + udev->autoresume_disabled = 0; + rc = usb_external_resume_device(udev); + + } else if (len == sizeof auto_string - 1 && + strncmp(buf, auto_string, len) == 0) { + udev->autosuspend_disabled = 0; + udev->autoresume_disabled = 0; + rc = usb_external_resume_device(udev); + + } else if (len == sizeof suspend_string - 1 && + strncmp(buf, suspend_string, len) == 0) { + udev->autosuspend_disabled = 0; + udev->autoresume_disabled = 1; + rc = usb_external_suspend_device(udev, PMSG_SUSPEND); + + } else + rc = -EINVAL; + + usb_unlock_device(udev); + return (rc < 0 ? rc : count); +} + +static DEVICE_ATTR(level, S_IRUGO | S_IWUSR, show_level, set_level); + static char power_group[] = "power"; static int add_power_attributes(struct device *dev) { int rc = 0; - if (is_usb_device(dev)) + if (is_usb_device(dev)) { rc = sysfs_add_file_to_group(&dev->kobj, &dev_attr_autosuspend.attr, power_group); + if (rc == 0) + rc = sysfs_add_file_to_group(&dev->kobj, + &dev_attr_level.attr, + power_group); + } return rc; } static void remove_power_attributes(struct device *dev) { sysfs_remove_file_from_group(&dev->kobj, + &dev_attr_level.attr, + power_group); + sysfs_remove_file_from_group(&dev->kobj, &dev_attr_autosuspend.attr, power_group); } diff --git a/include/linux/usb.h b/include/linux/usb.h index cc24d08..5e8e144 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -398,6 +398,8 @@ struct usb_device { unsigned auto_pm:1; /* autosuspend/resume in progress */ unsigned do_remote_wakeup:1; /* remote wakeup should be enabled */ + unsigned autosuspend_disabled:1; /* autosuspend and autoresume */ + unsigned autoresume_disabled:1; /* disabled by the user */ #endif }; #define to_usb_device(d) container_of(d, struct usb_device, dev) |