diff options
Diffstat (limited to 'drivers/usb/core/offload.c')
| -rw-r--r-- | drivers/usb/core/offload.c | 102 |
1 files changed, 59 insertions, 43 deletions
diff --git a/drivers/usb/core/offload.c b/drivers/usb/core/offload.c index 7c699f1b8d2b..9db3cfedd29c 100644 --- a/drivers/usb/core/offload.c +++ b/drivers/usb/core/offload.c @@ -25,33 +25,30 @@ */ int usb_offload_get(struct usb_device *udev) { - int ret; + int ret = 0; - usb_lock_device(udev); - if (udev->state == USB_STATE_NOTATTACHED) { - usb_unlock_device(udev); + if (!usb_get_dev(udev)) return -ENODEV; - } - if (udev->state == USB_STATE_SUSPENDED || - udev->offload_at_suspend) { - usb_unlock_device(udev); - return -EBUSY; + if (pm_runtime_get_if_active(&udev->dev) != 1) { + ret = -EBUSY; + goto err_rpm; } - /* - * offload_usage could only be modified when the device is active, since - * it will alter the suspend flow of the device. - */ - ret = usb_autoresume_device(udev); - if (ret < 0) { - usb_unlock_device(udev); - return ret; + spin_lock(&udev->offload_lock); + + if (udev->offload_pm_locked) { + ret = -EAGAIN; + goto err; } udev->offload_usage++; - usb_autosuspend_device(udev); - usb_unlock_device(udev); + +err: + spin_unlock(&udev->offload_lock); + pm_runtime_put_autosuspend(&udev->dev); +err_rpm: + usb_put_dev(udev); return ret; } @@ -69,35 +66,32 @@ EXPORT_SYMBOL_GPL(usb_offload_get); */ int usb_offload_put(struct usb_device *udev) { - int ret; + int ret = 0; - usb_lock_device(udev); - if (udev->state == USB_STATE_NOTATTACHED) { - usb_unlock_device(udev); + if (!usb_get_dev(udev)) return -ENODEV; - } - if (udev->state == USB_STATE_SUSPENDED || - udev->offload_at_suspend) { - usb_unlock_device(udev); - return -EBUSY; + if (pm_runtime_get_if_active(&udev->dev) != 1) { + ret = -EBUSY; + goto err_rpm; } - /* - * offload_usage could only be modified when the device is active, since - * it will alter the suspend flow of the device. - */ - ret = usb_autoresume_device(udev); - if (ret < 0) { - usb_unlock_device(udev); - return ret; + spin_lock(&udev->offload_lock); + + if (udev->offload_pm_locked) { + ret = -EAGAIN; + goto err; } /* Drop the count when it wasn't 0, ignore the operation otherwise. */ if (udev->offload_usage) udev->offload_usage--; - usb_autosuspend_device(udev); - usb_unlock_device(udev); + +err: + spin_unlock(&udev->offload_lock); + pm_runtime_put_autosuspend(&udev->dev); +err_rpm: + usb_put_dev(udev); return ret; } @@ -112,25 +106,47 @@ EXPORT_SYMBOL_GPL(usb_offload_put); * management. * * The caller must hold @udev's device lock. In addition, the caller should - * ensure downstream usb devices are all either suspended or marked as - * "offload_at_suspend" to ensure the correctness of the return value. + * ensure the device itself and the downstream usb devices are all marked as + * "offload_pm_locked" to ensure the correctness of the return value. * * Returns true on any offload activity, false otherwise. */ bool usb_offload_check(struct usb_device *udev) __must_hold(&udev->dev->mutex) { struct usb_device *child; - bool active; + bool active = false; int port1; + if (udev->offload_usage) + return true; + usb_hub_for_each_child(udev, port1, child) { usb_lock_device(child); active = usb_offload_check(child); usb_unlock_device(child); + if (active) - return true; + break; } - return !!udev->offload_usage; + return active; } EXPORT_SYMBOL_GPL(usb_offload_check); + +/** + * usb_offload_set_pm_locked - set the PM lock state of a USB device + * @udev: the USB device to modify + * @locked: the new lock state + * + * Setting @locked to true prevents offload_usage from being modified. This + * ensures that offload activities cannot be started or stopped during critical + * power management transitions, maintaining a stable state for the duration + * of the transition. + */ +void usb_offload_set_pm_locked(struct usb_device *udev, bool locked) +{ + spin_lock(&udev->offload_lock); + udev->offload_pm_locked = locked; + spin_unlock(&udev->offload_lock); +} +EXPORT_SYMBOL_GPL(usb_offload_set_pm_locked); |
