Re: [PATCH v2] clk: ti: Add support for dm814x ADPLL

[Tony Lindgren <tony@atomide.com>]

* Russell King - ARM Linux <linux@arm.linux.org.uk> [151211 08:16]:
> On Fri, Dec 11, 2015 at 07:48:54AM -0800, Tony Lindgren wrote:
> > There's a problem with MAX_CON_ID 16 hardcoded allocated name length.
> 
> Absolutely right...

Well adding the warning there allows people to at least see what's going
on.

> > In this case I have 13 instances of plls with 3 - 4 outputs each and I'd
> > like to use "481c5040.adpll.clkout" style naming starting with the instance
> > address. Also "adpll5.clkdcoldo" style naming would work,
> 
> Because it's a connection ID, not a clock _name_.  I see that we're still
> making all the same mistakes with clocks that were made years ago, and
> which lead down the path of amazingly complex drivers having conditional
> clock names and the like.

Yeah we certainly want to get out of the conditional name business.

> Is there a reason why you can't split this into separate device and input
> names, and use clk_get_sys() rather than passing NULL as the device to
> clk_get().  This is exactly why we've ended up with clk_get_sys(), to
> cater for the cases where there is no struct device to associate with the
> connection ID: the idea behind clk_get_sys() is that you pass the device
> name explicitly, along with the connection ID.

For most code yes, there's still a pile of shared legacy code relying on
the clock connection ID only.

So what do you envision people using for the connection ID in cases like
this? It needs to be unique, should relate to the documentation and fit
MAX_CON_ID. Something like "pll5.clkdcoldo" will still overflow for pll13
unless also the dot is left out :)

Regards,

Tony