diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/host/ehci-sched.c | 58 |
1 files changed, 42 insertions, 16 deletions
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c index dce305bd62a5..1c771045ccaa 100644 --- a/drivers/usb/host/ehci-sched.c +++ b/drivers/usb/host/ehci-sched.c @@ -1565,6 +1565,16 @@ itd_link_urb ( #define ISO_ERRS (EHCI_ISOC_BUF_ERR | EHCI_ISOC_BABBLE | EHCI_ISOC_XACTERR) +/* Process and recycle a completed ITD. Return true iff its urb completed, + * and hence its completion callback probably added things to the hardware + * schedule. + * + * Note that we carefully avoid recycling this descriptor until after any + * completion callback runs, so that it won't be reused quickly. That is, + * assuming (a) no more than two urbs per frame on this endpoint, and also + * (b) only this endpoint's completions submit URBs. It seems some silicon + * corrupts things if you reuse completed descriptors very quickly... + */ static unsigned itd_complete ( struct ehci_hcd *ehci, @@ -1577,6 +1587,7 @@ itd_complete ( int urb_index = -1; struct ehci_iso_stream *stream = itd->stream; struct usb_device *dev; + unsigned retval = false; /* for each uframe with a packet */ for (uframe = 0; uframe < 8; uframe++) { @@ -1610,15 +1621,9 @@ itd_complete ( } } - usb_put_urb (urb); - itd->urb = NULL; - itd->stream = NULL; - list_move (&itd->itd_list, &stream->free_list); - iso_stream_put (ehci, stream); - /* handle completion now? */ if (likely ((urb_index + 1) != urb->number_of_packets)) - return 0; + goto done; /* ASSERT: it's really the last itd for this urb list_for_each_entry (itd, &stream->td_list, itd_list) @@ -1628,6 +1633,7 @@ itd_complete ( /* give urb back to the driver ... can be out-of-order */ dev = urb->dev; ehci_urb_done(ehci, urb, 0); + retval = true; urb = NULL; /* defer stopping schedule; completion can submit */ @@ -1645,8 +1651,15 @@ itd_complete ( (stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out"); } iso_stream_put (ehci, stream); + /* OK to recycle this ITD now that its completion callback ran. */ +done: + usb_put_urb(urb); + itd->urb = NULL; + itd->stream = NULL; + list_move(&itd->itd_list, &stream->free_list); + iso_stream_put(ehci, stream); - return 1; + return retval; } /*-------------------------------------------------------------------------*/ @@ -1950,6 +1963,16 @@ sitd_link_urb ( #define SITD_ERRS (SITD_STS_ERR | SITD_STS_DBE | SITD_STS_BABBLE \ | SITD_STS_XACT | SITD_STS_MMF) +/* Process and recycle a completed SITD. Return true iff its urb completed, + * and hence its completion callback probably added things to the hardware + * schedule. + * + * Note that we carefully avoid recycling this descriptor until after any + * completion callback runs, so that it won't be reused quickly. That is, + * assuming (a) no more than two urbs per frame on this endpoint, and also + * (b) only this endpoint's completions submit URBs. It seems some silicon + * corrupts things if you reuse completed descriptors very quickly... + */ static unsigned sitd_complete ( struct ehci_hcd *ehci, @@ -1961,6 +1984,7 @@ sitd_complete ( int urb_index = -1; struct ehci_iso_stream *stream = sitd->stream; struct usb_device *dev; + unsigned retval = false; urb_index = sitd->index; desc = &urb->iso_frame_desc [urb_index]; @@ -1981,17 +2005,11 @@ sitd_complete ( desc->status = 0; desc->actual_length = desc->length - SITD_LENGTH (t); } - - usb_put_urb (urb); - sitd->urb = NULL; - sitd->stream = NULL; - list_move (&sitd->sitd_list, &stream->free_list); stream->depth -= stream->interval << 3; - iso_stream_put (ehci, stream); /* handle completion now? */ if ((urb_index + 1) != urb->number_of_packets) - return 0; + goto done; /* ASSERT: it's really the last sitd for this urb list_for_each_entry (sitd, &stream->td_list, sitd_list) @@ -2001,6 +2019,7 @@ sitd_complete ( /* give urb back to the driver */ dev = urb->dev; ehci_urb_done(ehci, urb, 0); + retval = true; urb = NULL; /* defer stopping schedule; completion can submit */ @@ -2018,8 +2037,15 @@ sitd_complete ( (stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out"); } iso_stream_put (ehci, stream); + /* OK to recycle this SITD now that its completion callback ran. */ +done: + usb_put_urb(urb); + sitd->urb = NULL; + sitd->stream = NULL; + list_move(&sitd->sitd_list, &stream->free_list); + iso_stream_put(ehci, stream); - return 1; + return retval; } |