[RFC/RFT 1/2] gpio/basic_mmio: add support for enable register

[Ryan Mallon]

On 05/07/11 15:10, Sekhar Nori wrote:
> Some GPIO controllers have an enable register
> which needs to be written to before a GPIO
> can be used.
>
> Add support for enabling the GPIO. At this
> time inverted logic for enabling the GPIO
> is not supported. This can be done by adding
> a disable register as and when a controller
> with this comes along.
>
> Signed-off-by: Sekhar Nori<nsekhar at ti.com>
> ---
>
<snip>

> static int bgpio_setup_io(struct bgpio_chip *bgc,
>   			  void __iomem *dat,
> @@ -369,6 +401,7 @@ int __devinit bgpio_init(struct bgpio_chip *bgc,
>   			 void __iomem *clr,
>   			 void __iomem *dirout,
>   			 void __iomem *dirin,
> +			 void __iomem *en,
>   			 bool big_endian)

The arguments to this function are getting a bit unwieldy :-). Maybe we 
need to introduce something like:

struct bgpio_chip_info {
     struct device *dev;
     unsigned long sz;
     void __iomem *dat;
     void __iomem *set;
     void __iomem *clr;
     void __iomem *dirout;
     void __iomem *dirin;
     void __iomem *en;
     bool big_endian;
};

and pass that to bgpio_init instead. It would have the added benefits of 
making the drivers more readable and that bgpio_chip_info structs in the 
drivers can probably be marked __initdata also.

Since you are already having to touch all of the call sites for 
bgpio_init this could be done as a separate patch along with this series.

~Ryan