Messages in this thread | | | Date | Fri, 18 Feb 2011 09:50:29 -0800 | From | Andres Salomon <> | Subject | Re: [PATCH 16/17] mc13xxx: mfd_cell is now implicitly available to drivers |
| |
On Fri, 18 Feb 2011 09:39:28 +0100 Uwe Kleine-König <u.kleine-koenig@pengutronix.de> wrote:
> On Wed, Feb 16, 2011 at 09:00:36AM -0800, Andres Salomon wrote: > > On Wed, 16 Feb 2011 10:41:54 +0100 > > Uwe Kleine-König <u.kleine-koenig@pengutronix.de> wrote: > > > > > On Fri, Feb 11, 2011 at 06:19:21PM -0800, Andres Salomon wrote: > > > > > > > > The cell's platform_data is now accessed with a helper function; > > > > change clients to use that, and remove the now-unused data_size. > > > > > > > > Note that mfd-core no longer makes a copy of platform_data, but > > > > the > > > why was this changed and where? I'm not able to find your > > > complete series via gmane. > > > > http://permalink.gmane.org/gmane.linux.kernel/1099164 > I still don't get the motivation of your patch set. For drivers that > don't need the mfd_cells you introduce another level of indirection. > And drivers that want to use mfd_cells as platform_data, they can > already now. > > Best regards > Uwe >
The main motivation for making mfd_cell available to all was to be able to provide functions within mfd-core (introduced in later patches/patchsets) that accept platform devices and operate on their mfd_cells. The mfd_cell used to be automatically carried by the pdevs, and I'm not entirely sure the reason for getting rid of that. It also (imo) cleans up a lot of things. For example, the mfd_cell API platform_data/driver_data stuff was unclear when I first encountered it, as various drivers were doing things completely differently (some incorrectly, as witnessed by some of the drivers that I modified that were using driver_data and had clients later calling set_drvdata on the same pdev). This is clearer, and provides a uniform way to do things that, afaict, sacrifices absolutely no flexibility or functionality. Yes, it adds some overhead by having a copy of the mfd_cell around in memory, but if that's really an issue it could be optimized further by not making a full copy of the mfd_cell. With the new wrappers (mfd_get_data/mfd_get_cell), this could be done without having to mess with drivers.
-- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |