[PATCH v3 3/5] reset: th1520: Prepare for supporting multiple controllers

Drew Fustini fustini at kernel.org
Thu Oct 30 05:17:58 PDT 2025


On Wed, Oct 29, 2025 at 03:13:46PM +0000, Yao Zi wrote:
> On Wed, Oct 29, 2025 at 12:54:25PM +0000, Drew Fustini wrote:
> > On Tue, Oct 14, 2025 at 01:10:30PM +0000, Yao Zi wrote:
> > > TH1520 SoC is divided into several subsystems, shipping distinct reset
> > > controllers with similar control logic. Let's make reset signal mapping
> > > a data structure specific to one compatible to prepare for introduction
> > > of more reset controllers in the future.
> > > 
> > > Signed-off-by: Yao Zi <ziyao at disroot.org>
> > > ---
> > >  drivers/reset/reset-th1520.c | 42 +++++++++++++++++++++++++-----------
> > >  1 file changed, 30 insertions(+), 12 deletions(-)
> > > 
> > > diff --git a/drivers/reset/reset-th1520.c b/drivers/reset/reset-th1520.c
> > > index 14d964a9c6b6..2b65a95ed021 100644
> > > --- a/drivers/reset/reset-th1520.c
> > > +++ b/drivers/reset/reset-th1520.c
> > [snip]
> > > @@ -138,22 +147,31 @@ static int th1520_reset_probe(struct platform_device *pdev)
> > >  	if (IS_ERR(priv->map))
> > >  		return PTR_ERR(priv->map);
> > >  
> > > -	/* Initialize GPU resets to asserted state */
> > > -	ret = regmap_update_bits(priv->map, TH1520_GPU_RST_CFG,
> > > -				 TH1520_GPU_RST_CFG_MASK, 0);
> > > -	if (ret)
> > > -		return ret;
> > > +	if (of_device_is_compatible(dev->of_node, "thead,th1520-reset")) {
> > 
> > Is there a reason that there is a now a conditional check for the
> > compatible here?
> 
> Yes, this regmap operation is for initializing GPU resets and thus
> modifies TH1520_GPU_RST_CFG, which only applies for the VO reset
> controller (with compatible "thead,th1520-reset") but not others, or
> other unrelated resets could be unexpectedly asserted.

Thanks for the explanation.

Reviewed-by: Drew Fustini <fustini at kernel.org>



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