diff options
| author | Matthijs Kooijman <matthijs@stdin.nl> | 2013-03-25 12:00:25 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-03-25 16:32:46 -0700 |
| commit | 8509f2f43a2b245ade076d1568daa2cf15446732 (patch) | |
| tree | dd9c82aaaf62afb143758b7eb2c6dbc8b70bffbd /drivers/staging/dwc2 | |
| parent | 257f65801520a5c888930d410f781d408a405990 (diff) | |
staging: dwc2: always release host channel after dequeueing
Previously, when an active urb was dequeued, its host channel would
not always be released. There is some special handling for this in
dwc2_hc_chhltd_intr_dma, but when it was the last urb/qtd in its qh, a
safeguard in dwc2_hc_n_intr would short-circuit and prevent the regular
interrupt handlers from running, without releasing the channel.
This is easily triggered when using a 3G modem using the option driver.
Opening and closing any ttyUSBx device will eat up a host channel that
is forever unusable from that point on.
Signed-off-by: Matthijs Kooijman <matthijs@stdin.nl>
[paulz@synopsys.com: fixed comment style and added a couple of NULL checks]
Signed-off-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/dwc2')
| -rw-r--r-- | drivers/staging/dwc2/hcd_intr.c | 33 |
1 files changed, 29 insertions, 4 deletions
diff --git a/drivers/staging/dwc2/hcd_intr.c b/drivers/staging/dwc2/hcd_intr.c index 4b007ab3649..8b68df89e33 100644 --- a/drivers/staging/dwc2/hcd_intr.c +++ b/drivers/staging/dwc2/hcd_intr.c @@ -708,7 +708,7 @@ static void dwc2_release_channel(struct dwc2_hsotg *hsotg, free_qtd = 1; break; case DWC2_HC_XFER_XACT_ERR: - if (qtd->error_count >= 3) { + if (qtd && qtd->error_count >= 3) { dev_vdbg(hsotg->dev, " Complete URB with transaction error\n"); free_qtd = 1; @@ -729,7 +729,7 @@ static void dwc2_release_channel(struct dwc2_hsotg *hsotg, case DWC2_HC_XFER_PERIODIC_INCOMPLETE: dev_vdbg(hsotg->dev, " Complete URB with I/O error\n"); free_qtd = 1; - if (qtd->urb) { + if (qtd && qtd->urb) { qtd->urb->status = -EIO; dwc2_host_complete(hsotg, qtd->urb->priv, qtd->urb, -EIO); @@ -1708,8 +1708,9 @@ static bool dwc2_halt_status_ok(struct dwc2_hsotg *hsotg, dev_dbg(hsotg->dev, "hcint 0x%08x, hcintmsk 0x%08x, hcsplt 0x%08x,\n", chan->hcint, hcintmsk, hcsplt); - dev_dbg(hsotg->dev, "qtd->complete_split %d\n", - qtd->complete_split); + if (qtd) + dev_dbg(hsotg->dev, "qtd->complete_split %d\n", + qtd->complete_split); dev_warn(hsotg->dev, "%s: no halt status, channel %d, ignoring interrupt\n", __func__, chnum); @@ -1937,7 +1938,31 @@ static void dwc2_hc_n_intr(struct dwc2_hsotg *hsotg, int chnum) chan->hcint = hcint; hcint &= hcintmsk; + /* + * If the channel was halted due to a dequeue, the qtd list might + * be empty or at least the first entry will not be the active qtd. + * In this case, take a shortcut and just release the channel. + */ + if (chan->halt_status == DWC2_HC_XFER_URB_DEQUEUE) { + /* + * If the channel was halted, this should be the only + * interrupt unmasked + */ + WARN_ON(hcint != HCINTMSK_CHHLTD); + if (hsotg->core_params->dma_desc_enable > 0) + dwc2_hcd_complete_xfer_ddma(hsotg, chan, chnum, + chan->halt_status); + else + dwc2_release_channel(hsotg, chan, NULL, + chan->halt_status); + return; + } + if (list_empty(&chan->qh->qtd_list)) { + /* + * TODO: Will this ever happen with the + * DWC2_HC_XFER_URB_DEQUEUE handling above? + */ dev_dbg(hsotg->dev, "## no QTD queued for channel %d ##\n", chnum); dev_dbg(hsotg->dev, |