From cca0eb67082c4cfda9a7e8cc4ef9ca5cd249cc37 Mon Sep 17 00:00:00 2001 From: Bjørn Mork Date: Fri, 10 Feb 2012 09:44:08 +0100 Subject: usb: cdc-wdm: make reset work with blocking IO MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a flag to tell wdm_read/wdm_write that a reset is in progress, and wake any blocking read/write before taking the mutexes. This allows the device to reset without waiting for blocking IO to finish. Signed-off-by: Bjørn Mork Acked-by: Oliver Neukum Signed-off-by: Greg Kroah-Hartman (cherry picked from commit 88044202756925ad47c51c2f634a4f2c17afe068) Signed-off-by: Bjørn Mork --- drivers/usb/class/cdc-wdm.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c index f3249812f85..f1020f33a5a 100644 --- a/drivers/usb/class/cdc-wdm.c +++ b/drivers/usb/class/cdc-wdm.c @@ -70,6 +70,7 @@ MODULE_DEVICE_TABLE (usb, wdm_ids); #define WDM_POLL_RUNNING 6 #define WDM_RESPONDING 7 #define WDM_SUSPENDING 8 +#define WDM_RESETTING 9 #define WDM_MAX 16 @@ -347,6 +348,10 @@ static ssize_t wdm_write else if (test_bit(WDM_IN_USE, &desc->flags)) r = -EAGAIN; + + if (test_bit(WDM_RESETTING, &desc->flags)) + r = -EIO; + if (r < 0) { kfree(buf); goto out; @@ -429,6 +434,10 @@ retry: rv = -ENODEV; goto err; } + if (test_bit(WDM_RESETTING, &desc->flags)) { + rv = -EIO; + goto err; + } usb_mark_last_busy(interface_to_usbdev(desc->intf)); if (rv < 0) { rv = -ERESTARTSYS; @@ -888,10 +897,6 @@ static int wdm_pre_reset(struct usb_interface *intf) { struct wdm_device *desc = usb_get_intfdata(intf); - mutex_lock(&desc->rlock); - mutex_lock(&desc->wlock); - kill_urbs(desc); - /* * we notify everybody using poll of * an exceptional situation @@ -899,9 +904,16 @@ static int wdm_pre_reset(struct usb_interface *intf) * message from the device is lost */ spin_lock_irq(&desc->iuspin); + set_bit(WDM_RESETTING, &desc->flags); /* inform read/write */ + set_bit(WDM_READ, &desc->flags); /* unblock read */ + clear_bit(WDM_IN_USE, &desc->flags); /* unblock write */ desc->rerr = -EINTR; spin_unlock_irq(&desc->iuspin); wake_up_all(&desc->wait); + mutex_lock(&desc->rlock); + mutex_lock(&desc->wlock); + kill_urbs(desc); + cancel_work_sync(&desc->rxwork); return 0; } @@ -910,6 +922,7 @@ static int wdm_post_reset(struct usb_interface *intf) struct wdm_device *desc = usb_get_intfdata(intf); int rv; + clear_bit(WDM_RESETTING, &desc->flags); rv = recover_from_urb_loss(desc); mutex_unlock(&desc->wlock); mutex_unlock(&desc->rlock); -- cgit v1.2.3