Re: [PATCH RFC] Input: Add Microchip AR1021 i2c touchscreen

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

On Fri, Jan 31, 2014 at 09:15:21AM -0800, Dmitry Torokhov wrote:
> Hi Chrisitian,
> 
> On Fri, Jan 31, 2014 at 12:40:19PM +0100, Christian Gmeiner wrote:
> > >> --- /dev/null
> > >> +++ b/drivers/input/touchscreen/ar1021_i2c.c
> > >> @@ -0,0 +1,201 @@
> > >> +/*
> > >> + * Microchip AR1021 driver for I2C
> > >> + *
> > >> + * Author: Christian Gmeiner <christian.gmeiner@gmail.com>
> > >> + *
> > >> + * License: GPL as published by the FSF.
> 
> By the way, you probably do not want GPL v1 to apply... Maybe say GPL v2
> or GPL v2 and later (depending on your preference and the license of the
> code you used as a base)?
> 
> > >> +
> > >> +static int ar1021_i2c_resume(struct device *dev)
> > >> +{
> > >> +     struct i2c_client *client = to_i2c_client(dev);
> > >> +
> > >> +     enable_irq(client->irq);
> > >
> > > You do not want to enable IRQ if there are no users (nobody opened
> > > device).
> > >
> > 
> > Okay.. but then I also do not need the disable_irq(..) call in
> > ar1021_i2c_suspend
> > and can totally remove the PM stuff - or?
> 
> No, I think you still need the PM methods, you just need to check if
> device is opened (take dev->mutex, check dev->users) and decide if you
> need to enable/disable IRQ or not.

Hmm, on the other hand enable/disable does the counting for you so maybe
you should leave it all as it was.

-- 
Dmitry