diff options
| author |   Bin Liu <b-liu@ti.com> | 2020-05-24 21:50:44 -0500 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-05-25 13:36:30 +0200 |
| commit | 1b967691ecdcf512bc33c0783158f760e5c1a9cf (patch) | |
| tree | 801bc67908158c9d87d8113febe1f9bbd02f09d8 /drivers/usb | |
| parent | Merge tag 'usb-for-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next (diff) | |
| download | wireguard-linux-1b967691ecdcf512bc33c0783158f760e5c1a9cf.tar.xz wireguard-linux-1b967691ecdcf512bc33c0783158f760e5c1a9cf.zip | |
usb: musb: return -ESHUTDOWN in urb when three-strikes error happened
When a USB device attached to a hub got disconnected, MUSB controller
generates RXCSR_RX_ERROR interrupt for the 3-strikes-out error.
Currently the MUSB host driver returns -EPROTO in current URB, then the
USB device driver could immediately resubmit the URB which causes MUSB
generate RXCSR_RX_ERROR interrupt again. This circle causes interrupt
storm then the hub never got a chance to report the USB device detach.
To fix the interrupt storm, change the URB return code to -ESHUTDOWN for
MUSB_RXCSR_H_ERROR interrupt, so that the USB device driver will not
immediately resubmit the URB.
Signed-off-by: Bin Liu <b-liu@ti.com>
Link: https://lore.kernel.org/r/20200525025049.3400-2-b-liu@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/musb/musb_host.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c index 8736f4251a22..8b7d22a0c0fb 100644 --- a/drivers/usb/musb/musb_host.c +++ b/drivers/usb/musb/musb_host.c @@ -1774,9 +1774,15 @@ void musb_host_rx(struct musb *musb, u8 epnum) status = -EPIPE; } else if (rx_csr & MUSB_RXCSR_H_ERROR) { - musb_dbg(musb, "end %d RX proto error", epnum); + dev_err(musb->controller, "ep%d RX three-strikes error", epnum); - status = -EPROTO; + /* + * The three-strikes error could only happen when the USB + * device is not accessible, for example detached or powered + * off. So return the fatal error -ESHUTDOWN so hopefully the + * USB device drivers won't immediately resubmit the same URB. + */ + status = -ESHUTDOWN; musb_writeb(epio, MUSB_RXINTERVAL, 0); rx_csr &= ~MUSB_RXCSR_H_ERROR; |