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USB: cdc-acm: simplify runtime PM locking

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We can simply the runtime PM locking as there's no need to check the
susp_count in the read path (at least not since killing the rx tasklet).

Specifically, the read urbs will never be resubmitted by the completion
handler when killed during suspend.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johan Hovold 2014-05-26 19:23:46 +02:00 committed by Greg Kroah-Hartman
parent 5292afa657
commit bbf0cb3e93
1 changed files with 6 additions and 11 deletions
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17
drivers/usb/class/cdc-acm.c
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@ -428,7 +428,7 @@ static void acm_read_bulk_callback(struct urb *urb)
/* throttle device if requested by tty */
spin_lock_irqsave(&acm->read_lock, flags);
acm->throttled = acm->throttle_req;
if (!acm->throttled && !acm->susp_count) {
if (!acm->throttled) {
spin_unlock_irqrestore(&acm->read_lock, flags);
acm_submit_read_urb(acm, rb->index, GFP_ATOMIC);
} else {
@ -1546,18 +1546,15 @@ static int acm_suspend(struct usb_interface *intf, pm_message_t message)
struct acm *acm = usb_get_intfdata(intf);
int cnt;
spin_lock_irq(&acm->read_lock);
spin_lock(&acm->write_lock);
spin_lock_irq(&acm->write_lock);
if (PMSG_IS_AUTO(message)) {
if (acm->transmitting) {
spin_unlock(&acm->write_lock);
spin_unlock_irq(&acm->read_lock);
spin_unlock_irq(&acm->write_lock);
return -EBUSY;
}
}
cnt = acm->susp_count++;
spin_unlock(&acm->write_lock);
spin_unlock_irq(&acm->read_lock);
spin_unlock_irq(&acm->write_lock);
if (cnt)
return 0;
@ -1573,8 +1570,7 @@ static int acm_resume(struct usb_interface *intf)
struct urb *urb;
int rv = 0;
spin_lock_irq(&acm->read_lock);
spin_lock(&acm->write_lock);
spin_lock_irq(&acm->write_lock);
if (--acm->susp_count)
goto out;
@ -1600,8 +1596,7 @@ static int acm_resume(struct usb_interface *intf)
rv = acm_submit_read_urbs(acm, GFP_ATOMIC);
}
out:
spin_unlock(&acm->write_lock);
spin_unlock_irq(&acm->read_lock);
spin_unlock_irq(&acm->write_lock);
return rv;
}