Re: [PATCH pinctrl/fixes] pinctrl: aspeed: Fix spurious mux failures on the AST2500

Andrew Jeffery andrew at
Thu Sep 12 20:26:05 AEST 2019

On Thu, 12 Sep 2019, at 17:53, Linus Walleij wrote:
> On Thu, Aug 29, 2019 at 8:17 AM Andrew Jeffery <andrew at> wrote:
> > Commit 674fa8daa8c9 ("pinctrl: aspeed-g5: Delay acquisition of regmaps")
> > was determined to be a partial fix to the problem of acquiring the LPC
> > Host Controller and GFX regmaps: The AST2500 pin controller may need to
> > fetch syscon regmaps during expression evaluation as well as when
> > setting mux state. For example, this case is hit by attempting to export
> > pins exposing the LPC Host Controller as GPIOs.
> >
> > An optional eval() hook is added to the Aspeed pinmux operation struct
> > and called from aspeed_sig_expr_eval() if the pointer is set by the
> > SoC-specific driver. This enables the AST2500 to perform the custom
> > action of acquiring its regmap dependencies as required.
> >
> > John Wang tested the fix on an Inspur FP5280G2 machine (AST2500-based)
> > where the issue was found, and I've booted the fix on Witherspoon
> > (AST2500) and Palmetto (AST2400) machines, and poked at relevant pins
> > under QEMU by forcing mux configurations via devmem before exporting
> > GPIOs to exercise the driver.
> >
> > Fixes: 7d29ed88acbb ("pinctrl: aspeed: Read and write bits in LPC and GFX controllers")
> > Fixes: 674fa8daa8c9 ("pinctrl: aspeed-g5: Delay acquisition of regmaps")
> > Reported-by: John Wang <wangzqbj at>
> > Tested-by: John Wang <wangzqbj at>
> > Signed-off-by: Andrew Jeffery <andrew at>
> Applied for fixes already yesterday!

Thanks! Hoping to avoid such late fixes in the future...


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