Commit Graph

3 Commits

Author SHA1 Message Date
Sudeep Holla 798523973d usb: isp1760: fix possible deadlock in isp1760_udc_irq
Use spin_{un,}lock_irq{save,restore} in isp1760_udc_{start,stop} to
prevent following potentially deadlock scenario between
isp1760_udc_{start,stop} and isp1760_udc_irq :

=================================
[ INFO: inconsistent lock state ]
4.0.0-rc2-00004-gf7bb2ef60173 #51 Not tainted
---------------------------------
inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
in:imklog/2118 [HC1[1]:SC0[0]:HE0:SE1] takes:
 (&(&udc->lock)->rlock){?.+...}, at: [<c0397a93>] isp1760_udc_irq+0x367/0x9dc
{HARDIRQ-ON-W} state was registered at:
  [<c05135b3>] _raw_spin_lock+0x23/0x30
  [<c0396b87>] isp1760_udc_start+0x23/0xf8
  [<c039dc21>] udc_bind_to_driver+0x71/0xb0
  [<c039de4f>] usb_gadget_probe_driver+0x53/0x9c
  [<bf80d0df>] usb_composite_probe+0x8a/0xa4 [libcomposite]
  [<bf8311a7>] 0xbf8311a7
  [<c00088c5>] do_one_initcall+0x8d/0x17c
  [<c050b92d>] do_init_module+0x49/0x148
  [<c0087323>] load_module+0xb7f/0xbc4
  [<c0087471>] SyS_finit_module+0x51/0x74
  [<c000d8c1>] ret_fast_syscall+0x1/0x68
irq event stamp: 4966
hardirqs last  enabled at (4965): [<c05137df>] _raw_spin_unlock_irq+0x1f/0x24
hardirqs last disabled at (4966): [<c00110b3>] __irq_svc+0x33/0x64
softirqs last  enabled at (4458): [<c0023475>] __do_softirq+0x23d/0x2d0
softirqs last disabled at (4389): [<c002380b>] irq_exit+0xef/0x15c

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&udc->lock)->rlock);
  <Interrupt>
    lock(&(&udc->lock)->rlock);

 *** DEADLOCK ***

1 lock held by in:imklog/2118:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<c010a101>] __fdget_pos+0x31/0x34

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2015-03-09 10:44:08 -05:00
Laurent Pinchart d21daf1e90 usb: isp1760: Fix USB disabled check
The isp1760 driver registration function returns an error if USB is
disabled. This made sense when the driver only supported host
controllers, but now that it supports peripheral controllers host
support isn't mandatory anymore.

Fix this by returning an error only when both the HCD and UDC functions
are disabled, either through the kernel configuration or at runtime.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2015-01-27 09:39:51 -06:00
Laurent Pinchart 7ef077a8ad usb: isp1760: Move driver from drivers/usb/host/ to drivers/usb/isp1760/
Now that this is DRD, it doesn't make sense to keep it under
drivers/usb/host.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2015-01-27 09:39:38 -06:00