[PATCH] pinctrl: aspeed: Force to disable the function's signal

Andrew Jeffery andrew at aj.id.au
Sat Aug 27 08:48:33 AEST 2022

On Sat, 27 Aug 2022, at 07:26, Linus Walleij wrote:
> On Thu, Aug 18, 2022 at 12:18 PM Billy Tsai <billy_tsai at aspeedtech.com> wrote:
>> When the driver want to disable the signal of the function, it doesn't
>> need to query the state of the mux function's signal on a pin. The
>> condition below will miss the disable of the signal:
>> Ball | Default | P0 Signal | P0 Expression               | Other
>> -----+---------+-----------+-----------------------------+----------
>>  E21   GPIOG0    SD2CLK      SCU4B4[16]=1 & SCU450[1]=1    GPIOG0
>> -----+---------+-----------+-----------------------------+----------
>>  B22   GPIOG1    SD2CMD      SCU4B4[17]=1 & SCU450[1]=1    GPIOG1
>> -----+---------+-----------+-----------------------------+----------
>> Assume the register status like below:
>> SCU4B4[16] == 1 & SCU4B4[17] == 1 & SCU450[1]==1
>> After the driver set the Ball E21 to the GPIOG0:
>> SCU4B4[16] == 0 & SCU4B4[17] == 1 & SCU450[1]==0
>> When the driver want to set the Ball B22 to the GPIOG1, the condition of
>> the SD2CMD will be false causing SCU4B4[17] not to be cleared.
>> Signed-off-by: Billy Tsai <billy_tsai at aspeedtech.com>
> I can't see the verdict for this patch? Will there be a new
> version, or are we in the middle of a discussion?
> I'd really like Andrew's ACK on the result before merging.

Apologies, it's been a bit of A Week :)

Given the approach has been discussed with the IP designer and solves a bug I'm okay for it to be merged. If we run into issues it is easy enough to back it out.

Acked-by: Andrew Jeffery <andrew at aj.id.au>

> Yours,
> Linus Walleij

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