[1/2,USB] /[misc]: Add waiting in transfer abortion

[1/2,USB] /[misc]: Add waiting in transfer abortion

[kirill.kirillovich.kapranov]

From: Kirill Kapranov <kirill.kirillovich.kapranov@gmail.com>

Add waiting for an URB transmit finish that let the last URB to be sent
(to be not discarded) during 'release' procedure. W/o this waiting,the
last frame will be nearly always lost.

A test case: an attempt of sending a single frame:
echo -en "\001mk255" >/dev/adutux0

Signed-off-by: Kirill Kapranov <kirill.kirillovich.kapranov@gmail.com>
---
 drivers/usb/misc/adutux.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/usb/misc/adutux.c b/drivers/usb/misc/adutux.c
index 4b87127..9669377 100644
--- a/drivers/usb/misc/adutux.c
+++ b/drivers/usb/misc/adutux.c
@@ -132,6 +132,8 @@ static void adu_abort_transfers(struct adu_device *dev)
 	spin_lock_irqsave(&dev->buflock, flags);
 	if (!dev->out_urb_finished) {
 		spin_unlock_irqrestore(&dev->buflock, flags);
+		wait_event_timeout(dev->write_wait, dev->out_urb_finished,
+			COMMAND_TIMEOUT);
 		usb_kill_urb(dev->interrupt_out_urb);
 	} else
 		spin_unlock_irqrestore(&dev->buflock, flags);

[1/2,USB] /[misc]: Add waiting in transfer abortion

[Oliver Neukum]

Am Samstag, den 17.02.2018, 23:01 +0200 schrieb
kirill.kirillovich.kapranov@gmail.com:
> From: Kirill Kapranov <kirill.kirillovich.kapranov@gmail.com>
> 
> Add waiting for an URB transmit finish that let the last URB to be sent
> (to be not discarded) during 'release' procedure. W/o this waiting,the
> last frame will be nearly always lost.

Hi,

is this the only driver with this issue?

	Regards
		Oliver
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[1/2,USB] /[misc]: Add waiting in transfer abortion

[kirill.kirillovich.kapranov]

Hi Oliver,

Unfortunately I have only ADU-208 USB/relay interface (adutux driver)
for testing.

At a glance, the following drivers have the pause in the same way on
'release' procedure, so they must work fine:
  legousbtower
  ldusb
  sisusbvga

Driver iowarrior doesn't have a pause before freeing buffer on
release, so it seems to be prone to the discussed issue.
---
Regards,
Kirill

On Mon, Feb 26, 2018 at 2:06 PM, Oliver Neukum <oneukum@suse.com> wrote:
> Am Samstag, den 17.02.2018, 23:01 +0200 schrieb
> kirill.kirillovich.kapranov@gmail.com:
>> From: Kirill Kapranov <kirill.kirillovich.kapranov@gmail.com>
>>
>> Add waiting for an URB transmit finish that let the last URB to be sent
>> (to be not discarded) during 'release' procedure. W/o this waiting,the
>> last frame will be nearly always lost.
>
> Hi,
>
> is this the only driver with this issue?
>
>         Regards
>                 Oliver
>
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