path: root/include/linux
diff options
authorAlan Stern <stern@rowland.harvard.edu>2013-01-25 17:09:42 -0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-01-25 15:06:01 -0800
commitda0aa7169b97d90f4af39a9dc84d58bbe19d7e78 (patch)
tree7d5e1d583787b07d6627f4acd46da1cc38deaf93 /include/linux
parent6e0c3339a6f19d748f16091d0a05adeb1e1f822b (diff)
USB: add usb_hcd_{start,end}_port_resume
This patch (as1649) adds a mechanism for host controller drivers to inform usbcore when they have begun or ended resume signalling on a particular root-hub port. The core will then make sure that the root hub does not get runtime-suspended while the port resume is going on. Since commit 596d789a211d134dc5f94d1e5957248c204ef850 (USB: set hub's default autosuspend delay as 0), the system tries to suspend hubs whenever they aren't in use. While a root-hub port is being resumed, the root hub does not appear to be in use. Attempted runtime suspends fail because of the ongoing port resume, but the PM core just keeps on trying over and over again. We want to prevent this wasteful effort. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux')
2 files changed, 5 insertions, 0 deletions
diff --git a/include/linux/usb.h b/include/linux/usb.h
index 689b14b26c8..4d22d0f6167 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -357,6 +357,8 @@ struct usb_bus {
int bandwidth_int_reqs; /* number of Interrupt requests */
int bandwidth_isoc_reqs; /* number of Isoc. requests */
+ unsigned resuming_ports; /* bit array: resuming root-hub ports */
#if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
struct mon_bus *mon_bus; /* non-null when associated */
int monitored; /* non-zero when monitored */
diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
index 608050b2545..0a78df5f6cf 100644
--- a/include/linux/usb/hcd.h
+++ b/include/linux/usb/hcd.h
@@ -430,6 +430,9 @@ extern void usb_hcd_poll_rh_status(struct usb_hcd *hcd);
extern void usb_wakeup_notification(struct usb_device *hdev,
unsigned int portnum);
+extern void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum);
+extern void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum);
/* The D0/D1 toggle bits ... USE WITH CAUTION (they're almost hcd-internal) */
#define usb_gettoggle(dev, ep, out) (((dev)->toggle[out] >> (ep)) & 1)
#define usb_dotoggle(dev, ep, out) ((dev)->toggle[out] ^= (1 << (ep)))