diff options
author | Alan Stern <stern@rowland.harvard.edu> | 2007-07-13 19:46:29 (GMT) |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2007-07-20 00:46:04 (GMT) |
commit | e7e7c360fb07020b24652843aec442325baad0ce (patch) | |
tree | 55a7a18cfcc87e86e4f91f309082aed0d7b8a956 /drivers/usb | |
parent | e94fa28f137813c2f6e05470b41bd8f3c5422a04 (diff) | |
download | linux-e7e7c360fb07020b24652843aec442325baad0ce.tar.xz |
UHCI: short control URBs get a status stage
It has recently been pointed out that short control transfers should
have a status stage, even if they generate an error because
URB_SHORT_NOT_OK was set. This patch (as935) changes uhci-hcd to
enable the status stage when this happens.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb')
-rw-r--r-- | drivers/usb/host/uhci-q.c | 59 |
1 files changed, 38 insertions, 21 deletions
diff --git a/drivers/usb/host/uhci-q.c b/drivers/usb/host/uhci-q.c index 4aed305..3bb908c 100644 --- a/drivers/usb/host/uhci-q.c +++ b/drivers/usb/host/uhci-q.c @@ -827,8 +827,10 @@ static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb, * If direction is "send", change the packet ID from SETUP (0x2D) * to OUT (0xE1). Else change it from SETUP to IN (0x69) and * set Short Packet Detect (SPD) for all data packets. + * + * 0-length transfers always get treated as "send". */ - if (usb_pipeout(urb->pipe)) + if (usb_pipeout(urb->pipe) || len == 0) destination ^= (USB_PID_SETUP ^ USB_PID_OUT); else { destination ^= (USB_PID_SETUP ^ USB_PID_IN); @@ -839,7 +841,12 @@ static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb, * Build the DATA TDs */ while (len > 0) { - int pktsze = min(len, maxsze); + int pktsze = maxsze; + + if (len <= pktsze) { /* The last data packet */ + pktsze = len; + status &= ~TD_CTRL_SPD; + } td = uhci_alloc_td(uhci); if (!td) @@ -866,20 +873,10 @@ static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb, goto nomem; *plink = LINK_TO_TD(td); - /* - * It's IN if the pipe is an output pipe or we're not expecting - * data back. - */ - destination &= ~TD_TOKEN_PID_MASK; - if (usb_pipeout(urb->pipe) || !urb->transfer_buffer_length) - destination |= USB_PID_IN; - else - destination |= USB_PID_OUT; - + /* Change direction for the status transaction */ + destination ^= (USB_PID_IN ^ USB_PID_OUT); destination |= TD_TOKEN_TOGGLE; /* End in Data1 */ - status &= ~TD_CTRL_SPD; - uhci_add_td_to_urbp(td, urbp); uhci_fill_td(td, status | TD_CTRL_IOC, destination | uhci_explen(0), 0); @@ -1185,10 +1182,18 @@ static int uhci_result_common(struct uhci_hcd *uhci, struct urb *urb) } } + /* Did we receive a short packet? */ } else if (len < uhci_expected_length(td_token(td))) { - /* We received a short packet */ - if (urb->transfer_flags & URB_SHORT_NOT_OK) + /* For control transfers, go to the status TD if + * this isn't already the last data TD */ + if (qh->type == USB_ENDPOINT_XFER_CONTROL) { + if (td->list.next != urbp->td_list.prev) + ret = 1; + } + + /* For bulk and interrupt, this may be an error */ + else if (urb->transfer_flags & URB_SHORT_NOT_OK) ret = -EREMOTEIO; /* Fixup needed only if this isn't the URB's last TD */ @@ -1208,10 +1213,6 @@ static int uhci_result_common(struct uhci_hcd *uhci, struct urb *urb) err: if (ret < 0) { - /* In case a control transfer gets an error - * during the setup stage */ - urb->actual_length = max(urb->actual_length, 0); - /* Note that the queue has stopped and save * the next toggle value */ qh->element = UHCI_PTR_TERM; @@ -1489,9 +1490,25 @@ __acquires(uhci->lock) { struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv; + if (qh->type == USB_ENDPOINT_XFER_CONTROL) { + + /* urb->actual_length < 0 means the setup transaction didn't + * complete successfully. Either it failed or the URB was + * unlinked first. Regardless, don't confuse people with a + * negative length. */ + urb->actual_length = max(urb->actual_length, 0); + + /* Report erroneous short transfers */ + if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) && + urb->actual_length < + urb->transfer_buffer_length && + urb->status == 0)) + urb->status = -EREMOTEIO; + } + /* When giving back the first URB in an Isochronous queue, * reinitialize the QH's iso-related members for the next URB. */ - if (qh->type == USB_ENDPOINT_XFER_ISOC && + else if (qh->type == USB_ENDPOINT_XFER_ISOC && urbp->node.prev == &qh->queue && urbp->node.next != &qh->queue) { struct urb *nurb = list_entry(urbp->node.next, |