Hi Grant, On Thu, Jul 07, 2011 at 02:40:54, Grant Likely wrote: > On Tue, Jul 05, 2011 at 04:15:44PM +1000, Ryan Mallon wrote: > > 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<[email protected]> > > >--- > > > > > <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. > > Or, what may be better is to make callers directly update the > bgpio_chip structure.
I started implementing it this way, but felt that the bgpio_chip structure also has many internal members (like the spinlock) and this method will require users to spend quite a bit of time figuring out which structure members they should initialize and which to leave for bgpio_init() to do for them. There is also the case of direction register which is set from either dirout or dirin depending upon whether the logic is inverted or not. The bgpio_chip however needs to deal with a single direction register offset. Considering these, I am getting inclined towards Ryan's suggestion. Thoughts? Thanks, Sekhar _______________________________________________ Davinci-linux-open-source mailing list [email protected] http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
