Subject: [PATCH v2 13/14] clk: shmobile: mstp: Consider "zb_clk" suitable for power management

From: [email-masked] (Michael Turquette)
Date: Mon, 22 Jun 2015 13:05:49 -0700

Quoting Geert Uytterhoeven (2015-05-28 11:53:38)
> Currently the CPG Clock Domain code looks for MSTP clocks to power
> manage a device.
> 
> Unfortunately, on R-Mobile APE6 (r8a73a4) and SH-Mobile AG5 (sh73a0),
> the Bus State Controller (BSC) is not power-managed by an MSTP clock,
> but by a plain CPG clock (zb_clk).  Add a special case to handle this,
> so the clock is properly managed, and devices connected to the BSC work
> as expected.
> 
> Signed-off-by: Geert Uytterhoeven <[email-masked]>
> ---
> v2:
>   - New.
> ---
>  drivers/clk/shmobile/clk-mstp.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/clk/shmobile/clk-mstp.c b/drivers/clk/shmobile/clk-mstp.c
> index 619f3eccefd4884f..19e2b11953383587 100644
> --- a/drivers/clk/shmobile/clk-mstp.c
> +++ b/drivers/clk/shmobile/clk-mstp.c
> @@ -258,6 +258,10 @@ int cpg_mstp_attach_dev(struct generic_pm_domain *domain, struct device *dev)
>                                             "renesas,cpg-mstp-clocks"))
>                         goto found;
>  
> +               /* BSC on r8a73a4/sh73a0 uses zb_clk instead of an mstp clock*/
> +               if (!strcmp(clkspec.np->name, "zb_clk"))
> +                       goto found;

Hello Geert,

Is the driver the right place to handle this corner case? What do you
think about linking zb_clk up to the bsc devicetree node for
r8a73a4/sh73a0?

Regards,
Mike

> +
>                 of_node_put(clkspec.np);
>                 i++;
>         }
> -- 
> 1.9.1
> 
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