USB: musb: fix session-bit runtime-PM quirk

The current session-bit quirk implementation does not prevent the retry
counter from underflowing, something which could break runtime PM and
keep the device active for a very long time (about 2^32 seconds) after a
disconnect.

This notably breaks the B-device timeout case, but could potentially
cause problems also when the controller is operating as an A-device.

Fixes: 2bff3916fd ("usb: musb: Fix PM for hub disconnect")
Cc: stable <stable@vger.kernel.org>     # 4.9
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johan Hovold 2017-10-09 22:46:07 -05:00 committed by Greg Kroah-Hartman
parent 765fb2f181
commit 4f190e0b9d
1 changed files with 4 additions and 4 deletions

View File

@ -1861,22 +1861,22 @@ static void musb_pm_runtime_check_session(struct musb *musb)
MUSB_DEVCTL_HR;
switch (devctl & ~s) {
case MUSB_QUIRK_B_INVALID_VBUS_91:
if (musb->quirk_retries--) {
if (musb->quirk_retries) {
musb_dbg(musb,
"Poll devctl on invalid vbus, assume no session");
schedule_delayed_work(&musb->irq_work,
msecs_to_jiffies(1000));
musb->quirk_retries--;
return;
}
/* fall through */
case MUSB_QUIRK_A_DISCONNECT_19:
if (musb->quirk_retries--) {
if (musb->quirk_retries) {
musb_dbg(musb,
"Poll devctl on possible host mode disconnect");
schedule_delayed_work(&musb->irq_work,
msecs_to_jiffies(1000));
musb->quirk_retries--;
return;
}
if (!musb->session)