diff options
Diffstat (limited to 'drivers/usb/host/xhci-mem.c')
-rw-r--r-- | drivers/usb/host/xhci-mem.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c index 4ed9f5f7a14..d64f5724bfc 100644 --- a/drivers/usb/host/xhci-mem.c +++ b/drivers/usb/host/xhci-mem.c @@ -625,6 +625,36 @@ static inline u32 xhci_get_endpoint_type(struct usb_device *udev, return type; } +/* Return the maximum endpoint service interval time (ESIT) payload. + * Basically, this is the maxpacket size, multiplied by the burst size + * and mult size. + */ +static inline u32 xhci_get_max_esit_payload(struct xhci_hcd *xhci, + struct usb_device *udev, + struct usb_host_endpoint *ep) +{ + int max_burst; + int max_packet; + + /* Only applies for interrupt or isochronous endpoints */ + if (usb_endpoint_xfer_control(&ep->desc) || + usb_endpoint_xfer_bulk(&ep->desc)) + return 0; + + if (udev->speed == USB_SPEED_SUPER) { + if (ep->ss_ep_comp) + return ep->ss_ep_comp->desc.wBytesPerInterval; + xhci_warn(xhci, "WARN no SS endpoint companion descriptor.\n"); + /* Assume no bursts, no multiple opportunities to send. */ + return ep->desc.wMaxPacketSize; + } + + max_packet = ep->desc.wMaxPacketSize & 0x3ff; + max_burst = (ep->desc.wMaxPacketSize & 0x1800) >> 11; + /* A 0 in max burst means 1 transfer per ESIT */ + return max_packet * (max_burst + 1); +} + int xhci_endpoint_init(struct xhci_hcd *xhci, struct xhci_virt_device *virt_dev, struct usb_device *udev, @@ -636,6 +666,7 @@ int xhci_endpoint_init(struct xhci_hcd *xhci, struct xhci_ring *ep_ring; unsigned int max_packet; unsigned int max_burst; + u32 max_esit_payload; ep_index = xhci_get_endpoint_index(&ep->desc); ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, ep_index); @@ -703,6 +734,26 @@ int xhci_endpoint_init(struct xhci_hcd *xhci, default: BUG(); } + max_esit_payload = xhci_get_max_esit_payload(xhci, udev, ep); + ep_ctx->tx_info = MAX_ESIT_PAYLOAD_FOR_EP(max_esit_payload); + + /* + * XXX no idea how to calculate the average TRB buffer length for bulk + * endpoints, as the driver gives us no clue how big each scatter gather + * list entry (or buffer) is going to be. + * + * For isochronous and interrupt endpoints, we set it to the max + * available, until we have new API in the USB core to allow drivers to + * declare how much bandwidth they actually need. + * + * Normally, it would be calculated by taking the total of the buffer + * lengths in the TD and then dividing by the number of TRBs in a TD, + * including link TRBs, No-op TRBs, and Event data TRBs. Since we don't + * use Event Data TRBs, and we don't chain in a link TRB on short + * transfers, we're basically dividing by 1. + */ + ep_ctx->tx_info |= AVG_TRB_LENGTH_FOR_EP(max_esit_payload); + /* FIXME Debug endpoint context */ return 0; } |