[PATCH 3.12 19/19] usbcore: set lpm_capable field for LPM capable root hubs

Greg Kroah-Hartman
2013-11-18T18:39:05Z

From: Xenia Ragiadakou <burzalodowa@gmail.com>

commit 9df89d85b407690afa46ddfbccc80bec6869971d upstream.

This patch sets the lpm_capable field for root hubs with LPM capabilities.

Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Reported-by: Martin MOKREJS <mmokrejs@gmail.com>
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/core/hcd.c | 1 +
drivers/usb/core/hub.c | 7 ++++++-
drivers/usb/core/usb.h | 1 +
3 files changed, 8 insertions(+), 1 deletion(-)

--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1033,6 +1033,7 @@ static int register_root_hub(struct usb_
dev_name(&usb_dev->dev), retval);
return retval;
}
+ usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
}

retval = usb_new_device (usb_dev);
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -135,7 +135,7 @@ struct usb_hub *usb_hub_to_struct_hub(st
return usb_get_intfdata(hdev->actconfig->interface[0]);
}

-static int usb_device_supports_lpm(struct usb_device *udev)
+int usb_device_supports_lpm(struct usb_device *udev)
{
/* USB 2.1 (and greater) devices indicate LPM support through
* their USB 2.0 Extended Capabilities BOS descriptor.
@@ -156,6 +156,11 @@ static int usb_device_supports_lpm(struc
"Power management will be impacted.\n");
return 0;
}
+
+ /* udev is root hub */
+ if (!udev->parent)
+ return 1;
+
if (udev->parent->lpm_capable)
return 1;

--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -35,6 +35,7 @@ extern int usb_get_device_descriptor(str
unsigned int size);
extern int usb_get_bos_descriptor(struct usb_device *dev);
extern void usb_release_bos_descriptor(struct usb_device *dev);
+extern int usb_device_supports_lpm(struct usb_device *udev);
extern char *usb_cache_string(struct usb_device *udev, int index);
extern int usb_set_configuration(struct usb_device *dev, int configuration);
extern int usb_choose_configuration(struct usb_device *udev);