diff options
| author | Stefano Babic <sbabic@denx.de> | 2012-10-15 11:20:22 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-28 10:56:12 -0700 |
| commit | da2f7d4a8ec01898617e0d1a1808c60b607e32fa (patch) | |
| tree | 37a721a6b5e92eb52135eb50b238961fa717fd56 /drivers | |
| parent | 9e9e9cf3d8712b1af470dbc3c2c7e4c6bb4b0531 (diff) | |
usb: musb: am35xx: drop spurious unplugging a device
commit 6ff1f3d3bd7c69c62ca5773b1b684bce42eff06a upstream.
On AM3517, tx and rx interrupt are detected together with
the disconnect event. This generates a kernel panic in musb_interrupt,
because rx / tx are handled after disconnect.
This issue was seen on a Technexion's TAM3517 SOM. Unplugging a device,
tx / rx interrupts together with disconnect are detected. This brings
to kernel panic like this:
[ 68.526153] Unable to handle kernel NULL pointer dereference at virtual address 00000011
[ 68.534698] pgd = c0004000
[ 68.537536] [00000011] *pgd=00000000
[ 68.541351] Internal error: Oops: 17 [#1] ARM
[ 68.545928] Modules linked in:
[ 68.549163] CPU: 0 Not tainted (3.6.0-rc5-00020-g9e05905 #178)
[ 68.555694] PC is at rxstate+0x8/0xdc
[ 68.559539] LR is at musb_interrupt+0x98/0x858
[ 68.564239] pc : [<c035cd88>] lr : [<c035af1c>] psr: 40000193
[ 68.564239] sp : ce83fb40 ip : d0906410 fp : 00000000
[ 68.576293] r10: 00000000 r9 : cf3b0e40 r8 : 00000002
[ 68.581817] r7 : 00000019 r6 : 00000001 r5 : 00000001 r4 : 000000d4
[ 68.588684] r3 : 00000000 r2 : 00000000 r1 : ffffffcc r0 : cf23c108
[ 68.595550] Flags: nZcv IRQs off FIQs on Mode SVC_32 ISA ARM Segment ke
Note: this behavior is not seen with a USB hub, while it is
easy to reproduce connecting a USB-pen directly to the USB-A of
the board.
Drop tx / rx interrupts if disconnect is detected.
Signed-off-by: Stefano Babic <sbabic@denx.de>
CC: Felipe Balbi <balbi@ti.com>
Tested-by: Dmitry Lifshitz <lifshitz@compulab.co.il>
Tested-by: Igor Grinberg <grinberg@compulab.co.il>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/usb/musb/am35x.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/usb/musb/am35x.c b/drivers/usb/musb/am35x.c index 7a95ab87ac00..ee9ec137dc73 100644 --- a/drivers/usb/musb/am35x.c +++ b/drivers/usb/musb/am35x.c @@ -312,6 +312,12 @@ static irqreturn_t am35x_musb_interrupt(int irq, void *hci) ret = IRQ_HANDLED; } + /* Drop spurious RX and TX if device is disconnected */ + if (musb->int_usb & MUSB_INTR_DISCONNECT) { + musb->int_tx = 0; + musb->int_rx = 0; + } + if (musb->int_tx || musb->int_rx || musb->int_usb) ret |= musb_interrupt(musb); |