Re: [PATCH] clk: mediatek: mt8186: Change I2C 4/5/6 ap clocks parent to infra

From: Yu-chang Lee (李禹璋)
Date: Tue Oct 24 2023 - 03:47:20 EST


On Tue, 2023-10-24 at 10:58 +0800, Chen-Yu Tsai wrote:
> On Tue, Oct 24, 2023 at 10:52 AM Stephen Boyd <sboyd@xxxxxxxxxx>
> wrote:
> >
> > Quoting Chen-Yu Tsai (2023-10-19 22:06:35)
> > > On Thu, Oct 19, 2023 at 8:49 PM AngeloGioacchino Del Regno
> > > <angelogioacchino.delregno@xxxxxxxxxxxxx> wrote:
> > > >
> > > > Fix the parenting of clocks imp_iic_wrap_ap_clock_i2c{4-6}, as
> > > > those
> > > > are effectively parented to infra_ao_i2c{4-6} and not to the
> > > > I2C_AP.
> > > > This permits the correct (and full) enablement and disablement
> > > > of the
> > > > I2C4, I2C5 and I2C6 bus clocks, satisfying the whole clock tree
> > > > of
> > > > those.
> > > >
> > > > As an example, when requesting to enable
> > > > imp_iic_wrap_ap_clock_i2c4:
> > > >
> > > > Before: infra_ao_i2c_ap -> imp_iic_wrap_ap_clock_i2c4
> > > > After: infra_ao_i2c_ap -> infra_ao_i2c4 ->
> > > > imp_iic_wrap_ap_clock_i2c4
> > > >
> > > > Fixes: 66cd0b4b0ce5 ("clk: mediatek: Add MT8186 imp i2c wrapper
> > > > clock support")
> > > > Signed-off-by: AngeloGioacchino Del Regno <
> > > > angelogioacchino.delregno@xxxxxxxxxxxxx>
> > >
> > > I'm curious about what led to discovering this error?
> > >
> >
> > Is that an acked-by?
>
> MediaTek engineers are saying the original code already matches the
> documentation provided by their hardware engineers. I'm trying to get
> them to respond on the mailing list.
>
> ChenYu
>
After checking with I2C clock hardware designer there is no
infra_ao_i2c{4-6} clock gate in between. And the clock document at hand
aslo shows the same result. Generallly speaking, we would like to keep
sw setting align with the hardware design document. I would recommand
not to change this part of code, but enable infra_ao_i2c{4-6} prior to
the usage of imp_iic_wrap_ap_clock_i2c clock.

Best Regards,
YuChang