[PATCH v4] clk: ti: Add support for dm814x ADPLL

[Tero Kristo]

On 12/22/2015 05:27 PM, Tony Lindgren wrote:
> On dm814x we have 13 ADPLLs with 3 to 4 outputs on each. The
> ADPLLs have several dividers and muxes controlled by a shared
> control register for each PLL.
>
> Note that for the clocks to work as device drivers for booting on
> dm814x, this patch depends on "ARM: OMAP2+: Change core_initcall
> levels to postcore_initcall".
>
> Also note that this patch does not implement clk_set_rate for the
> PLL, that will be posted later on when available.
>
> Cc: Michael Turquette <mturquette at baylibre.com>
> Cc: Stephen Boyd <sboyd at codeaurora.org>
> Cc: Tero Kristo <t-kristo at ti.com>
> Signed-off-by: Tony Lindgren <tony at atomide.com>
> ---
>
> If no more comments, Tero can you please apply into an immutable
> branch against v4.4-rc1 that I can merge in too?
>
> Changes since v3:
>
> - We want to create the clkdev entry for all clocks, not just outputs
> - ti_adpll_wait_lock loops did not do the right thing
> - We want to use CLK_GET_RATE_NOCACHE in ti_adpll_init_dco

I have just one comment below still, once that is addressed:

Conditionally-acked-by: Tero Kristo <t-kristo at ti.com>

Stephen / Michael, can you pick this up for next merge? I don't have 
anything else coming for the window this time, and I am probably going 
to be on vacation just nicely to not be able to push anything anyway.

<snip>

> +
> +/* Warn if clkout or clkoutx2 try to set unavailable parent */
> +static int ti_adpll_clkout_set_parent(struct clk_hw *hw, u8 index)
> +{
> +	struct ti_adpll_clkout_data *co = to_clkout(hw);
> +	struct ti_adpll_data *d = co->adpll;
> +
> +	if (ti_adpll_clock_is_bypass(d) != index)
> +		return -EAGAIN;
> +

I think this part is still somewhat weird. You are not doing anything 
useful in this function, so do you need to implement it at all? Just 
returning -EINVAL always might work also. EAGAIN is wrong return value 
anyway as it can pretty much never succeed.

-Tero

> +	return 0;
> +}
> +

<snip>