[PATCH/RFC] ARM: shmobile: r8a7790: Fix HSUSB clock to hp_clk from mp_clk

[Geert Uytterhoeven]

Hi Kaneko-san, Mizuguchi-san,

On Sun, Feb 15, 2015 at 3:49 PM, Yoshihiro Kaneko <ykaneko0929 at gmail.com> wrote:
> From: Kazuya Mizuguchi <kazuya.mizuguchi.ks at renesas.com>
>
> HSUSB uses hp_clk for H/W register access.

That indeed seems to be true, and that's what this patch is changing.

> HSUSB uses mp_clk for USB-DMAC access.

However, page 64-2 doesn't mention the MP clock for USB-DMAC:
   "AXI bus clock (ZSφ: 260 MHz), HPB bus clock (HPφ: 130 MHz).
    USB local bus clock (48 MHz)"
So your statement doesn't seem to be true?

Note that mstp3_clks in dtsi has hp_clk as the parent for both usbdmac0 and
usbdmac1, so if your statement would be true, that has to changed, too?

The same is true for other members of the R-Car Gen2 family, e.g. your patch
for r8a7791.

> The clock is defined for H/W register access.
>
> Signed-off-by: Kazuya Mizuguchi <kazuya.mizuguchi.ks at renesas.com>
> Signed-off-by: Yoshihiro Kaneko <ykaneko0929 at gmail.com>
> ---
>
> This patch is based on devel branch of Simon Horman's renesas tree.
>
>  arch/arm/boot/dts/r8a7790.dtsi | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/boot/dts/r8a7790.dtsi b/arch/arm/boot/dts/r8a7790.dtsi
> index 24de994..113edf2 100644
> --- a/arch/arm/boot/dts/r8a7790.dtsi
> +++ b/arch/arm/boot/dts/r8a7790.dtsi

> @@ -1132,7 +1133,7 @@
>                 mstp7_clks: mstp7_clks at e615014c {
>                         compatible = "renesas,r8a7790-mstp-clocks", "renesas,cpg-mstp-clocks";
>                         reg = <0 0xe615014c 0 4>, <0 0xe61501c4 0 4>;
> -                       clocks = <&mp_clk>, <&mp_clk>, <&zs_clk>, <&zs_clk>, <&p_clk>,
> +                       clocks = <&mp_clk>, <&hp_clk>, <&zs_clk>, <&zs_clk>, <&p_clk>,
>                                  <&p_clk>, <&zx_clk>, <&zx_clk>, <&zx_clk>, <&zx_clk>,
>                                  <&zx_clk>;
>                         #clock-cells = <1>;

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds