diff options
Diffstat (limited to 'drivers/usb/core/hub.c')
| -rw-r--r-- | drivers/usb/core/hub.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 916bcd539afa..09bd3c3ad8b1 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -38,6 +38,9 @@ #define USB_VENDOR_GENESYS_LOGIC 0x05e3 #define HUB_QUIRK_CHECK_PORT_AUTOSUSPEND 0x01 +#define USB_TP_TRANSMISSION_DELAY 40 /* ns */ +#define USB_TP_TRANSMISSION_DELAY_MAX 65535 /* ns */ + /* Protect struct usb_device->state and ->children members * Note: Both are also protected by ->dev.sem, except that ->state can * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */ @@ -1350,6 +1353,20 @@ static int hub_configure(struct usb_hub *hub, goto fail; } + /* + * Accumulate wHubDelay + 40ns for every hub in the tree of devices. + * The resulting value will be used for SetIsochDelay() request. + */ + if (hub_is_superspeed(hdev) || hub_is_superspeedplus(hdev)) { + u32 delay = __le16_to_cpu(hub->descriptor->u.ss.wHubDelay); + + if (hdev->parent) + delay += hdev->parent->hub_delay; + + delay += USB_TP_TRANSMISSION_DELAY; + hdev->hub_delay = min_t(u32, delay, USB_TP_TRANSMISSION_DELAY_MAX); + } + maxchild = hub->descriptor->bNbrPorts; dev_info(hub_dev, "%d port%s detected\n", maxchild, (maxchild == 1) ? "" : "s"); @@ -4597,7 +4614,20 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1, if (retval >= 0) retval = -EMSGSIZE; } else { + u32 delay; + retval = 0; + + delay = udev->parent->hub_delay; + udev->hub_delay = min_t(u32, delay, + USB_TP_TRANSMISSION_DELAY_MAX); + retval = usb_set_isoch_delay(udev); + if (retval) { + dev_dbg(&udev->dev, + "Failed set isoch delay, error %d\n", + retval); + retval = 0; + } break; } } |