From ecdc0a590268f1926ed8534a040a390c77d20948 Mon Sep 17 00:00:00 2001 From: Franck Bui-Huu Date: Wed, 12 Jul 2006 10:09:41 +0200 Subject: [PATCH] USB: usbcore get rid of the timer in usb_start_wait_urb() This patch uses completion timeout instead of a timer to implement a timeout when submitting an URB in usb_start_wait_urb(). It also fixes a small issue. With the previous code, if no timeout happened and the URB's status was set to ECONNRESET value, the code assumed wrongly that a timeout had occured. Signed-off-by: Franck Bui-Huu Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/message.c | 73 +++++++++++++++----------------------- 1 file changed, 29 insertions(+), 44 deletions(-) diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 4cc8d3e67db7..49cfd7928a1c 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -23,59 +23,44 @@ static void usb_api_blocking_completion(struct urb *urb, struct pt_regs *regs) } -static void timeout_kill(unsigned long data) -{ - struct urb *urb = (struct urb *) data; - - usb_unlink_urb(urb); -} - -// Starts urb and waits for completion or timeout -// note that this call is NOT interruptible, while -// many device driver i/o requests should be interruptible -static int usb_start_wait_urb(struct urb *urb, int timeout, int* actual_length) +/* + * Starts urb and waits for completion or timeout. Note that this call + * is NOT interruptible. Many device driver i/o requests should be + * interruptible and therefore these drivers should implement their + * own interruptible routines. + */ +static int usb_start_wait_urb(struct urb *urb, int timeout, int *actual_length) { - struct completion done; - struct timer_list timer; - int status; + struct completion done; + unsigned long expire; + int status; init_completion(&done); urb->context = &done; urb->actual_length = 0; status = usb_submit_urb(urb, GFP_NOIO); - - if (status == 0) { - if (timeout > 0) { - init_timer(&timer); - timer.expires = jiffies + msecs_to_jiffies(timeout); - timer.data = (unsigned long)urb; - timer.function = timeout_kill; - /* grr. timeout _should_ include submit delays. */ - add_timer(&timer); - } - wait_for_completion(&done); + if (unlikely(status)) + goto out; + + expire = timeout ? msecs_to_jiffies(timeout) : MAX_SCHEDULE_TIMEOUT; + if (!wait_for_completion_timeout(&done, expire)) { + + dev_dbg(&urb->dev->dev, + "%s timed out on ep%d%s len=%d/%d\n", + current->comm, + usb_pipeendpoint(urb->pipe), + usb_pipein(urb->pipe) ? "in" : "out", + urb->actual_length, + urb->transfer_buffer_length); + + usb_kill_urb(urb); + status = urb->status == -ENOENT ? -ETIMEDOUT : urb->status; + } else status = urb->status; - /* note: HCDs return ETIMEDOUT for other reasons too */ - if (status == -ECONNRESET) { - dev_dbg(&urb->dev->dev, - "%s timed out on ep%d%s len=%d/%d\n", - current->comm, - usb_pipeendpoint(urb->pipe), - usb_pipein(urb->pipe) ? "in" : "out", - urb->actual_length, - urb->transfer_buffer_length - ); - if (urb->actual_length > 0) - status = 0; - else - status = -ETIMEDOUT; - } - if (timeout > 0) - del_timer_sync(&timer); - } - +out: if (actual_length) *actual_length = urb->actual_length; + usb_free_urb(urb); return status; } -- 2.20.1