Re: [PATCH v2] input: add driver support for Sharp gp2ap002a00fproximity sensor

From: Felipe Balbi
Date: Tue Nov 15 2011 - 03:48:06 EST


Hi,

On Tue, Nov 15, 2011 at 12:46:09AM -0800, Dmitry Torokhov wrote:
> > On Tue, Nov 15, 2011 at 12:29:26AM -0800, Dmitry Torokhov wrote:
> > > > > > + error = input_register_device(dt->device);
> > > > > > + if (error) {
> > > > > > + dev_err(&dt->device->dev, "device registration failed\n");
> > > > > > + input_free_device(dt->device);
> > > > >
> > > > > If you swap request_threaded_irq() and input_register_device() so that
> > > > > registration is the last action error handling will be much simpler.
> > > > >
> > > >
> > > > I am getting a bit confused here, since you asked me to swap the order
> > > > of request_threaded_irq() and input_register_device() in my previous
> > > > version as well. Swapping again will take us back to square one or maybe
> > > > I am misinterpreting your comment?
> > >
> > > Gah, sorry, a bit of boilerplate slipped in. You already have the calls
> > > in right order, you just need proper labels.
> > >
> > >
> > > input_dev = input_allocate_device();
> > > if (!input_dev) {
> > > dev_err(...);
> > > error = -ENOMEM;
> > > goto err_free_mem;
> > > }
> > >
> > > ... set up input device fully ...
> > >
> > > error = request_threaded_irq(...);
> > > if (error) {
> > > dev_err(...);
> > > goto err_free_input_dev;
> > > }
> > >
> > > error = input_register_device(input_dev);
> > > if (error) {
> > > dev_err(...);
> > > goto err_free_irq;
> > > }
> >
> > are you sure this is right order ? Won't this create a very small
> > timeframe where we could try to call input_report_switch() and
> > input_sync() on an unregistered input device ??
> >
>
> Yes, this is fine. As long as input device was allocated with
> input_allocate_device() it can be used by input_report_*() and
> input_sync() even tough device may not be registered yet - the events
> will simply be dropped.

good to know, thanks :-)

--
balbi

Attachment: signature.asc
Description: Digital signature