Re: [PATCH 1/1] Staging: hv: mousevsc: Move the mouse driver out of staging

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Sun, Oct 23, 2011 at 03:45:14PM +0000, KY Srinivasan wrote:
> > > +
> > > +	t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
> > > +	if (t == 0) {
> > > +		ret = -ETIMEDOUT;
> > > +		goto cleanup;
> > > +	}
> > > +
> > > +	response = &input_dev->protocol_resp;
> > > +
> > > +	if (!response->response.approved) {
> > > +		pr_err("synthhid protocol request failed (version %d)",
> > > +		       SYNTHHID_INPUT_VERSION);
> > > +		ret = -ENODEV;
> > > +		goto cleanup;
> > > +	}
> > > +
> > > +	t = wait_for_completion_timeout(&input_dev->wait_event, 5*HZ);
> > 
> > We just completed the wait for this completion, why are we waiting on
> > the same completion again?
> 
> In response to our initial query, we expect the host to respond back with two
> distinct pieces of information; we wait for both these responses.

I think you misunderstand how completion works in Linux. IIRC about
Windows events they are different ;) You can not signal completion
several times and then expect to wait corrsponding number of times. Once
you signal completion is it, well, complete.

>  
> > 
> > > +	if (t == 0) {
> > > +		ret = -ETIMEDOUT;
> > > +		goto cleanup;
> > > +	}
> > > +
> > > +	/*
> > > +	 * We should have gotten the device attr, hid desc and report
> > > +	 * desc at this point
> > > +	 */
> > > +	if (input_dev->dev_info_status)
> > > +		ret = -ENOMEM;
> > 
> > -ENOMEM seems wrong.
> > 
> There are many failures here and not being able to allocate memory is the 
> primary one; and so I chose to capture that.

Any chance that these failures have their own exit paths?

Thanks.

-- 
Dmitry