[PATCH 4/7] spi: pl022: attempt to get sspclk by name

On Tuesday 11 February 2014 15:04:38 Russell King - ARM Linux wrote:

On Tue, Feb 11, 2014 at 03:08:06PM +0100, Arnd Bergmann wrote:

quoted

On Tuesday 11 February 2014, Mark Brown wrote:

quoted

On Tue, Feb 11, 2014 at 11:37:09AM +0000, Mark Rutland wrote:

quoted

-     pl022->clk = devm_clk_get(&adev->dev, NULL);
+     /*
+      * For compatibility with old DTBs and platform data, fall back to the
+      * first clock if there's not an explicitly named "sspclk" entry.
+      */
+     pl022->clk = devm_clk_get(&adev->dev, "sspclk");
+     if (IS_ERR(pl022->clk))
+             pl022->clk = devm_clk_get(&adev->dev, NULL);
+

I'll just have a bit of a grumble here and point out that this sort of
stuff always worries me with the convention of using nameless clocks -
it causes hassle adding further clocks.

I think the best solution for this is to continue with anonymous clocks
rather than adding names after the fact. This could be done (for DT-only
drivers) using the of_clk_get() interface that takes an index, or
we could add a generic dev_clk_get_index() or similar interface that
has the same behavior but also works for clkdev.

Mixing devm_* and non-devm_* interfaces doesn't work.  If you want to do
that, devm_of_clk_get() would be a prerequisit.

Yes, good point. So if we want to do it, we would have to add a new
function anyway, there is just the question whether it should be
devm_of_clk_get() or devm_clk_get_index() if that can also work for
non-DT devices. Do you think the latter actually makes sense in
the clkdev interfaces? I'm not familiar enough with the code to
tell how that would be implemented in a reasonable way.

	Arnd