diff options
Diffstat (limited to 'drivers/usb/core')
| -rw-r--r-- | drivers/usb/core/Kconfig | 14 | ||||
| -rw-r--r-- | drivers/usb/core/hub.c | 13 |
2 files changed, 26 insertions, 1 deletions
diff --git a/drivers/usb/core/Kconfig b/drivers/usb/core/Kconfig index dfacc478a8fc..351ede4b5de2 100644 --- a/drivers/usb/core/Kconfig +++ b/drivers/usb/core/Kconfig @@ -32,6 +32,20 @@ config USB_DEFAULT_PERSIST If you have any questions about this, say Y here, only say N if you know exactly what you are doing. +config USB_FEW_INIT_RETRIES + bool "Limit USB device initialization to only a few retries" + help + When a new USB device is detected, the kernel tries very hard + to initialize and enumerate it, with lots of nested retry loops. + This almost always works, but when it fails it can take a long time. + This option tells the kernel to make only a few retry attempts, + so that the total time required for a failed initialization is + no more than 30 seconds (as required by the USB OTG spec). + + Say N here unless you require new-device enumeration failure to + occur within 30 seconds (as might be needed in an embedded + application). + config USB_DYNAMIC_MINORS bool "Dynamic USB minor allocation" help diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 70eaf4ab236f..17202b2ee063 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2705,10 +2705,20 @@ static unsigned hub_is_wusb(struct usb_hub *hub) } +#ifdef CONFIG_USB_FEW_INIT_RETRIES +#define PORT_RESET_TRIES 2 +#define SET_ADDRESS_TRIES 1 +#define GET_DESCRIPTOR_TRIES 1 +#define GET_MAXPACKET0_TRIES 1 +#define PORT_INIT_TRIES 4 + +#else #define PORT_RESET_TRIES 5 #define SET_ADDRESS_TRIES 2 #define GET_DESCRIPTOR_TRIES 2 +#define GET_MAXPACKET0_TRIES 3 #define PORT_INIT_TRIES 4 +#endif /* CONFIG_USB_FEW_INIT_RETRIES */ #define HUB_ROOT_RESET_TIME 60 /* times are in msec */ #define HUB_SHORT_RESET_TIME 10 @@ -4691,7 +4701,8 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1, * 255 is for WUSB devices, we actually need to use * 512 (WUSB1.0[4.8.1]). */ - for (operations = 0; operations < 3; ++operations) { + for (operations = 0; operations < GET_MAXPACKET0_TRIES; + ++operations) { buf->bMaxPacketSize0 = 0; r = usb_control_msg(udev, usb_rcvaddr0pipe(), USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, |