[PATCH 03/12] staging: comedi: das16: use comedi_legacy_detach()

[Dan Carpenter]

On Wed, Apr 17, 2013 at 11:17:42AM -0700, H Hartley Sweeten wrote:
> Use the new comedi_legacy_detach() helper in the (*detach) to release
> the first I/O region requested by this driver.
> 
> An additional I/O region is requested for some of the boards this driver
> supports. Save the iobase for that region in the private data so that
> the (*detach) knows it needs to be released.
> 
> Signed-off-by: H Hartley Sweeten <hsweeten at visionengravers.com>
> Cc: Ian Abbott <abbotti at mev.co.uk>
> Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
> ---
>  drivers/staging/comedi/drivers/das16.c | 22 ++++++++--------------
>  1 file changed, 8 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/staging/comedi/drivers/das16.c b/drivers/staging/comedi/drivers/das16.c
> index c2b5015..b2826710 100644
> --- a/drivers/staging/comedi/drivers/das16.c
> +++ b/drivers/staging/comedi/drivers/das16.c
> @@ -393,6 +393,8 @@ struct das16_private_struct {
>  	struct timer_list timer;	/*  for timed interrupt */
>  	volatile short timer_running;
>  	volatile short timer_mode;	/*  true if using timer mode */
> +
> +	unsigned long extra_iobase;
>  };
>  
>  static int das16_cmd_test(struct comedi_device *dev, struct comedi_subdevice *s,
> @@ -1122,11 +1124,9 @@ static int das16_attach(struct comedi_device *dev, struct comedi_devconfig *it)
>  		/* Request an additional region for the 8255 */
>  		ret = __comedi_request_region(dev, dev->iobase + 0x400,
>  					      board->size & 0x3ff);
> -		if (ret) {
> -			release_region(dev->iobase, 0x10);
> -			dev->iobase = 0;
> -			return -EIO;
> -		}
> +		if (ret)
> +			return ret;
> +		devpriv->extra_iobase = dev->iobase + 0x400;
>  	}
>  
>  	/*  probe id bits to make sure they are consistent */

I understand that we clean up later but can the board work if the
second request region fails?  That's why we don't return an error
here any more?

regards,
dan carpenter