From 624defa12f304b4d11eda309bc207fa5a1900d0f Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Wed, 2 Sep 2009 12:14:28 -0700 Subject: [PATCH] USB: xhci: Support interrupt transfers. Interrupt transfers are submitted to the xHCI hardware using the same TRB type as bulk transfers. Re-use the bulk transfer enqueueing code to enqueue interrupt transfers. Interrupt transfers are a bit different than bulk transfers. When the interrupt endpoint is to be serviced, the xHC will consume (at most) one TD. A TD (comprised of sg list entries) can take several service intervals to transmit. The important thing for device drivers to note is that if they use the scatter gather interface to submit interrupt requests, they will not get data sent from two different scatter gather lists in the same service interval. For now, the xHCI driver will use the service interval from the endpoint's descriptor (bInterval). Drivers will need a hook to poll at a more frequent interval. Set urb->interval to the interval that the xHCI hardware will use. Signed-off-by: Sarah Sharp Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-hcd.c | 5 ++++ drivers/usb/host/xhci-ring.c | 48 +++++++++++++++++++++++++++++++++++- drivers/usb/host/xhci.h | 3 +++ 3 files changed, 55 insertions(+), 1 deletion(-) diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c index 1d4a1e3f9533..e478a63488fb 100644 --- a/drivers/usb/host/xhci-hcd.c +++ b/drivers/usb/host/xhci-hcd.c @@ -727,6 +727,11 @@ int xhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags) ret = xhci_queue_bulk_tx(xhci, GFP_ATOMIC, urb, slot_id, ep_index); spin_unlock_irqrestore(&xhci->lock, flags); + } else if (usb_endpoint_xfer_int(&urb->ep->desc)) { + spin_lock_irqsave(&xhci->lock, flags); + ret = xhci_queue_intr_tx(xhci, GFP_ATOMIC, urb, + slot_id, ep_index); + spin_unlock_irqrestore(&xhci->lock, flags); } else { ret = -EINVAL; } diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index aac379e1c883..ff5e6bc2299d 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1072,7 +1072,12 @@ static int handle_tx_event(struct xhci_hcd *xhci, else status = 0; } else { - xhci_dbg(xhci, "Successful bulk transfer!\n"); + if (usb_endpoint_xfer_bulk(&td->urb->ep->desc)) + xhci_dbg(xhci, "Successful bulk " + "transfer!\n"); + else + xhci_dbg(xhci, "Successful interrupt " + "transfer!\n"); status = 0; } break; @@ -1464,6 +1469,47 @@ static void giveback_first_trb(struct xhci_hcd *xhci, int slot_id, ring_ep_doorbell(xhci, slot_id, ep_index); } +/* + * xHCI uses normal TRBs for both bulk and interrupt. When the interrupt + * endpoint is to be serviced, the xHC will consume (at most) one TD. A TD + * (comprised of sg list entries) can take several service intervals to + * transmit. + */ +int xhci_queue_intr_tx(struct xhci_hcd *xhci, gfp_t mem_flags, + struct urb *urb, int slot_id, unsigned int ep_index) +{ + struct xhci_ep_ctx *ep_ctx = xhci_get_ep_ctx(xhci, + xhci->devs[slot_id]->out_ctx, ep_index); + int xhci_interval; + int ep_interval; + + xhci_interval = EP_INTERVAL_TO_UFRAMES(ep_ctx->ep_info); + ep_interval = urb->interval; + /* Convert to microframes */ + if (urb->dev->speed == USB_SPEED_LOW || + urb->dev->speed == USB_SPEED_FULL) + ep_interval *= 8; + /* FIXME change this to a warning and a suggestion to use the new API + * to set the polling interval (once the API is added). + */ + if (xhci_interval != ep_interval) { + if (!printk_ratelimit()) + dev_dbg(&urb->dev->dev, "Driver uses different interval" + " (%d microframe%s) than xHCI " + "(%d microframe%s)\n", + ep_interval, + ep_interval == 1 ? "" : "s", + xhci_interval, + xhci_interval == 1 ? "" : "s"); + urb->interval = xhci_interval; + /* Convert back to frames for LS/FS devices */ + if (urb->dev->speed == USB_SPEED_LOW || + urb->dev->speed == USB_SPEED_FULL) + urb->interval /= 8; + } + return xhci_queue_bulk_tx(xhci, GFP_ATOMIC, urb, slot_id, ep_index); +} + static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags, struct urb *urb, int slot_id, unsigned int ep_index) { diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index bc64b500feb8..a7728aa91582 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -581,6 +581,7 @@ struct xhci_ep_ctx { /* bit 15 is Linear Stream Array */ /* Interval - period between requests to an endpoint - 125u increments. */ #define EP_INTERVAL(p) ((p & 0xff) << 16) +#define EP_INTERVAL_TO_UFRAMES(p) (1 << (((p) >> 16) & 0xff)) /* ep_info2 bitmasks */ /* @@ -1223,6 +1224,8 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags, struct urb *urb, int slot_id, unsigned int ep_index); int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags, struct urb *urb, int slot_id, unsigned int ep_index); +int xhci_queue_intr_tx(struct xhci_hcd *xhci, gfp_t mem_flags, struct urb *urb, + int slot_id, unsigned int ep_index); int xhci_queue_configure_endpoint(struct xhci_hcd *xhci, dma_addr_t in_ctx_ptr, u32 slot_id); int xhci_queue_evaluate_context(struct xhci_hcd *xhci, dma_addr_t in_ctx_ptr, -- 2.30.2