Re: [PATCH v5 4/6] reset: imx8mp-audiomix: Extend the driver usage

[Philipp Zabel <p.zabel@pengutronix.de>]

On Fr, 2025-11-21 at 01:29 -0800, Laurentiu Mihalcea wrote:
> On 11/14/2025 8:02 AM, Philipp Zabel wrote:
> > On Fr, 2025-11-14 at 05:37 -0800, Laurentiu Mihalcea wrote:
> > > From: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>
> > > 
> > > Switch to per-device reset map to allow reusing the driver for other NXP
> > > block control IPs.
> > > 
> > > Reviewed-by: Daniel Baluta <daniel.baluta@nxp.com>
> > > Reviewed-by: Frank Li <Frank.Li@nxp.com>
> > > Signed-off-by: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>
> > > ---
> > >  drivers/reset/reset-imx8mp-audiomix.c | 18 ++++++++++++++++--
> > >  1 file changed, 16 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/drivers/reset/reset-imx8mp-audiomix.c b/drivers/reset/reset-imx8mp-audiomix.c
> > > index 35df9bd5f71a..d3396f37d1ff 100644
> > > --- a/drivers/reset/reset-imx8mp-audiomix.c
> > > +++ b/drivers/reset/reset-imx8mp-audiomix.c
> > > @@ -24,7 +24,12 @@ struct imx8mp_reset_map {
> > >  	bool active_low;
> > >  };
> > >  
> > > -static const struct imx8mp_reset_map reset_map[] = {
> > > +struct imx8mp_reset_info {
> > > +	const struct imx8mp_reset_map *map;
> > > +	int num_lines;
> > > +};
> > > +
> > > +static const struct imx8mp_reset_map imx8mp_reset_map[] = {
> > >  	[IMX8MP_AUDIOMIX_EARC_RESET] = {
> > >  		.offset	= IMX8MP_AUDIOMIX_EARC_RESET_OFFSET,
> > >  		.bit = 0,
> > > @@ -42,9 +47,15 @@ static const struct imx8mp_reset_map reset_map[] = {
> > >  	},
> > >  };
> > >  
> > > +static const struct imx8mp_reset_info imx8mp_reset_info = {
> > > +	.map = imx8mp_reset_map,
> > > +	.num_lines = ARRAY_SIZE(imx8mp_reset_map),
> > > +};
> > > +
> > >  struct imx8mp_audiomix_reset {
> > >  	struct reset_controller_dev rcdev;
> > >  	struct regmap *regmap;
> > > +	const struct imx8mp_reset_info *rinfo;
> > Since only rinfo->map is used in imx8mp_audiomix_update(), you could
> > directly store a
> > 
> > 	const struct imx8mp_reset_map *map;
> 
> 
> hm, that is true, but I wonder if instead of replacing "rinfo" with "map", it would be better to
> 
> keep "rinfo" and add an out-of-bounds check for the reset ID in imx8mp_audiomix_update().
> 
> Something like:
> 
> 
>                 if (id >= priv->rinfo->num_lines)
> 
>                     return -EINVAL;
> 
> 
> we are stuck with "struct imx8mp_reset_info" so might as well fully make use of it?

There is no need to check this again. You copy rinfo->num_lines into
rcdev.nr_resets, which is checked in of_reset_simple_xlate() before the
reset_control is even handed to the consumer.

regards
Philipp