[PATCH 0/6] clk: Initial feedback for off-SoC slow bus clocks

On Mon, Jul 11, 2011 at 11:28:56AM +0100, Russell King - ARM Linux wrote:

On Mon, Jul 11, 2011 at 12:07:59PM +0200, Sascha Hauer wrote:

quoted

On Mon, Jul 11, 2011 at 10:31:24AM +0100, Russell King - ARM Linux wrote:

quoted

On Mon, Jul 11, 2011 at 11:53:44AM +0900, Mark Brown wrote:

quoted

The biggest issue I ran into was that as the clocks are all registered
by name with the API if you've got two instances of the same off-SoC
device in the system you'll not be able to disambiguate between the
clocks it provides.

Sigh.  That sounds like yet more trash.  Obviously whoever thought
up that doesn't actually understand clks.

Nope. In the patches Jeremy posted clocks have a name, but this name
is not meant to be used with clk_get. clk_get is still implemented
in clkdev, so the matching between clocks and devices is independent
of the clock name.

In earlier versions of Jeremys patches the clock name was only present
when debugfs was compiled in and I think it can be changed back to this.

That said the debugfs support (which is not present in Jeremys latest
series) would break if two clocks with the same name have the same
parent, because the clock core would try to create to debugfs entries
with the same name.

If that's all its for, then can't some other solution for debugfs names
(lets stop calling them clock names to avoid confusion) be found -
such as

	sprintf(debugfsname, "%s@%p", clk->debugfsprefix, clk);

Sounds good. During my tests on i.MX I found it very convenient to have
speaking debugfs names, so I vote for this suggestion instead the
following ones.

Or how about using something like this:

$debugfs/clkdev/device/connection -> ../../clk/<name-of-clk>
$debugfs/clk/<name-of-clk>

where <name-of-clk> could just be the address of the struct clk (which
eliminates the need to pass any names in) or some prefix plus an
incrementing identifier, or just an incrementing number.

I did think about introducing such a scheme along with clkdev (and did
have some code but that's long gone), but without the $debugfs/clk/ bit
being standardized, it wouldn't have worked.

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