Hello Russell,
On Mon, 17 Aug 2009, Russell King - ARM Linux wrote:
> On Mon, Aug 17, 2009 at 04:06:44AM -0600, Paul Walmsley wrote:
> >
> > On Mon, 17 Aug 2009, Russell King - ARM Linux wrote:
> >
> > > On Mon, Aug 17, 2009 at 03:14:45AM -0600, Paul Walmsley wrote:
> > > > What it does remove is the need for internal core code to fake up a struct
> > > > device simply to access a clock. It also allows us to harmonize the
> > > > clock names, used internally in core code, with the hardware reality,
> > > > which uses unique names to identify clocks.
> > >
> > > That problem is already solved. clk_get_sys()
> >
> > That solves the first problem, but not the second. Is there some reason
> > that OMAP core code (aside from the clkdev mapping structures in
> > mach-omap2/clock*.c) should know, or care, whether a platform device name
> > is bound to that clock?
>
> It's not a platform device name. It's a _device_ name. It really has
> precisely nothing what so ever to do with platform devices. clkdev
> really couldn't care if the struct device you gave it was representing
> a PCI device, AMBA device or a platform device.
Sure, I mistyped. So, to revise the question,
Is there some reason that OMAP core code (aside from the clkdev mapping
structures in mach-omap2/clock*.c) should know, or care, whether a device
name is bound to that clock?
> > On OMAP, we have uniquely-named clock lines in the technical
> > documentation. It is possible that other platforms don't have this. But
> > for us, I'd submit that it makes more sense for internal core code to
> > fetch a clock documented as "MMC1_FCLK" with:
> >
> > c = omap_clk_get_by_name("mmc1_fck");
>
> The point is - why invent yet another different clock lookup mechanism
> when there already exists adequate mechanisms?
Is there an existing mechanism that allows us to look up a clock by simply
using its unique name?
> Second question - there is going to be debugfs support for clkdev coming
> along. Have you involved yourself with those discussions to ensure that
> what is being proposed is going to be suitable for OMAPs usage, or is
> OMAP going to implement its own version independently?
It's already implemented for OMAP, in mainline, from commit
137b3ee27ab1b27dba081542476054836978ca45. At the moment, clkdev doesn't
have anything here. When debugfs support is added to clkdev, I'm sure
we'll be happy to switch to it.
- Paul
--
To unsubscribe from this list: send the line "unsubscribe linux-arm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
