diff options
Diffstat (limited to 'drivers/usb/core/hcd.c')
| -rw-r--r-- | drivers/usb/core/hcd.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 4225d5e72131..8e64adf8e4d5 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -39,6 +39,7 @@ #include <asm/unaligned.h> #include <linux/platform_device.h> #include <linux/workqueue.h> +#include <linux/pm_runtime.h> #include <linux/usb.h> #include <linux/usb/hcd.h> @@ -1025,6 +1026,49 @@ static int register_root_hub(struct usb_hcd *hcd) return retval; } +/* + * usb_hcd_start_port_resume - a root-hub port is sending a resume signal + * @bus: the bus which the root hub belongs to + * @portnum: the port which is being resumed + * + * HCDs should call this function when they know that a resume signal is + * being sent to a root-hub port. The root hub will be prevented from + * going into autosuspend until usb_hcd_end_port_resume() is called. + * + * The bus's private lock must be held by the caller. + */ +void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum) +{ + unsigned bit = 1 << portnum; + + if (!(bus->resuming_ports & bit)) { + bus->resuming_ports |= bit; + pm_runtime_get_noresume(&bus->root_hub->dev); + } +} +EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume); + +/* + * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal + * @bus: the bus which the root hub belongs to + * @portnum: the port which is being resumed + * + * HCDs should call this function when they know that a resume signal has + * stopped being sent to a root-hub port. The root hub will be allowed to + * autosuspend again. + * + * The bus's private lock must be held by the caller. + */ +void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum) +{ + unsigned bit = 1 << portnum; + + if (bus->resuming_ports & bit) { + bus->resuming_ports &= ~bit; + pm_runtime_put_noidle(&bus->root_hub->dev); + } +} +EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume); /*-------------------------------------------------------------------------*/ |