RE: [RESEND PATCH] ARM: SAMSUNG: Add s3c_setparent_clksrc ins3c_set_clksrc

From: Kukjin Kim
Date: Tue Dec 20 2011 - 23:07:18 EST


jhbird.choi@xxxxxxxxxxx wrote:
>
> From: Jonghwan Choi <jhbird.choi@xxxxxxxxxxx>
>
> Currently we have to run clk_set_parent to change clock source.
> But if there are sources & parent defined, it means we will select a
> parent
> in multiple clock sources. So sources & parent are already defined,
> set the parent clock int s3c_set_clksrc.
> Then we can reduce many clk_set_parent function in driver or setup_clock
> function.
>
> Signed-off-by: Jonghwan Choi <jhbird.choi@xxxxxxxxxxx>
> ---
> arch/arm/plat-samsung/clock-clksrc.c | 8 ++++++++
> 1 files changed, 8 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/plat-samsung/clock-clksrc.c b/arch/arm/plat-
> samsung/clock-clksrc.c
> index ae8b850..61dfe0d 100644
> --- a/arch/arm/plat-samsung/clock-clksrc.c
> +++ b/arch/arm/plat-samsung/clock-clksrc.c
> @@ -140,6 +140,14 @@ void __init_or_cpufreq s3c_set_clksrc(struct
> clksrc_clk *clk, bool announce)
> return;
> }
>
> + if (clk->sources && clk->clk.parent) {
> + if (s3c_setparent_clksrc(&clk->clk, clk->clk.parent)) {
> + printk(KERN_ERR "%s: bad source is %s\n",
> + clk->clk.name, clk->clk.parent->name);
> + return;
> + }
> + }
> +
> clksrc = __raw_readl(clk->reg_src.reg);
> clksrc &= mask;
> clksrc >>= clk->reg_src.shift;
> --
> 1.7.1

Hmm, I think, this is not good. If there is a mux which includes clock sources, as you know, its parent clock can be selected
according to the value of reg_src and it should be changed by calling clk_set_parent() even though this can help in some kind of
view. And the clksrc_clk depends on SoC not board so the clk.parent cannot be fixed at the clock.c file.

Thanks.

Best regards,
Kgene.
--
Kukjin Kim <kgene.kim@xxxxxxxxxxx>, Senior Engineer,
SW Solution Development Team, Samsung Electronics Co., Ltd.

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