RE: [PATCH v3 1/3] soc: renesas: rz-sysc: Register auxiliary device for PWRRDY power sequencer

Hi Bartosz and Geert,

Thanks for the feedback.

> -----Original Message-----
> From: Bartosz Golaszewski <[email protected]>
> Sent: 13 August 2026 14:27
> Subject: Re: [PATCH v3 1/3] soc: renesas: rz-sysc: Register auxiliary device for PWRRDY power sequencer
> 
> On Wed, 12 Aug 2026 13:50:03 +0200, Biju <[email protected]> said:
> > From: Biju Das <[email protected]>
> >
> > Some RZ SoCs (e.g. RZ/G3L) have a PWRRDY register that is controlled
> > through a power sequencer rather than directly by the SYSC driver.
> >
> > Add a pwrrdy_pwrseq flag to struct rz_sysc_soc_id_init_data to mark
> > SoCs with this property, and set it for RZ/G3L. When set,
> > rz_sysc_probe() registers a "pwrseq-pwrrdy" auxiliary device so a
> > dedicated driver can handle the PWRRDY sequencing.
> >
> > Signed-off-by: Biju Das <[email protected]>
> > ---
> > v2->v3:
> >  * Updated commit description by dropping devm_add_action_or_reset().
> >  * Config now selects AUXILIARY_BUS to avoid compilation issues.
> >  * Dropped the cast in devm_auxiliary_device_create().
> > v1->v2:
> >  * Switched to devm_auxiliary_device_create().
> >  * Added regmap parameter to rz_sysc_pwrrdy_pwrseq_init(),so that regmap
> >    can be passed as platform data.
> > ---
> >  drivers/soc/renesas/Kconfig          |  1 +
> >  drivers/soc/renesas/r9a08g046-sysc.c |  1 +
> >  drivers/soc/renesas/rz-sysc.c        | 21 +++++++++++++++++++++
> >  drivers/soc/renesas/rz-sysc.h        |  2 ++
> >  4 files changed, 25 insertions(+)
> >
> > diff --git a/drivers/soc/renesas/Kconfig b/drivers/soc/renesas/Kconfig
> > index fdf18ed2dfc2..ab1c25fc2656 100644
> > --- a/drivers/soc/renesas/Kconfig
> > +++ b/drivers/soc/renesas/Kconfig
> > @@ -485,6 +485,7 @@ config RZN1_IRQMUX  config SYSC_RZ
> >  	bool "System controller for RZ SoCs" if COMPILE_TEST
> >  	select MFD_SYSCON
> > +	select AUXILIARY_BUS
> >
> >  config SYSC_R9A08G045
> >  	bool "Renesas System controller support for R9A08G045 (RZ/G3S)" if COMPILE_TEST
> > diff --git a/drivers/soc/renesas/r9a08g046-sysc.c b/drivers/soc/renesas/r9a08g046-sysc.c
> > index 90db9d383539..cd129c727461 100644
> > --- a/drivers/soc/renesas/r9a08g046-sysc.c
> > +++ b/drivers/soc/renesas/r9a08g046-sysc.c
> > @@ -76,6 +76,7 @@ static const struct rz_sysc_soc_id_init_data rzg3l_sysc_soc_id_init_data __initc
> >  	.devid_offset = 0xa04,
> >  	.revision_mask = GENMASK(31, 28),
> >  	.specific_id_mask = GENMASK(27, 0),
> > +	.pwrrdy_pwrseq = true,
> >  };
> >
> >  const struct rz_sysc_init_data rzg3l_sysc_init_data __initconst = {
> > diff --git a/drivers/soc/renesas/rz-sysc.c b/drivers/soc/renesas/rz-sysc.c
> > index 161e8c38eea6..79c6af934721 100644
> > --- a/drivers/soc/renesas/rz-sysc.c
> > +++ b/drivers/soc/renesas/rz-sysc.c
> > @@ -5,6 +5,7 @@
> >   * Copyright (C) 2024 Renesas Electronics Corp.
> >   */
> >
> > +#include <linux/auxiliary_bus.h>
> >  #include <linux/bitfield.h>
> >  #include <linux/cleanup.h>
> >  #include <linux/io.h>
> > @@ -84,6 +85,22 @@ static int rz_sysc_soc_init(struct rz_sysc *sysc, const struct of_device_id *mat
> >  	return 0;
> >  }
> >
> > +static int rz_sysc_pwrrdy_pwrseq_init(struct device *dev, struct regmap *regmap,
> > +				      const struct rz_sysc_init_data *data)
> > +{
> > +	const struct rz_sysc_soc_id_init_data *soc_data = data->soc_id_init_data;
> > +	struct auxiliary_device *adev;
> > +
> > +	if (!soc_data->pwrrdy_pwrseq)
> > +		return 0;
> > +
> > +	adev = devm_auxiliary_device_create(dev, "pwrseq-pwrrdy", regmap);
> > +	if (!adev)
> > +		return -ENODEV;
> > +
> > +	return 0;
> > +}
> > +
> >  static const struct of_device_id rz_sysc_match[] = {
> >  #ifdef CONFIG_SYSC_R9A08G045
> >  	{ .compatible = "renesas,r9a08g045-sysc", .data = &rzg3s_sysc_init_data },
> > @@ -149,6 +166,10 @@ static int rz_sysc_probe(struct platform_device *pdev)
> >  	if (IS_ERR(regmap))
> >  		return PTR_ERR(regmap);
> >
> > +	ret = rz_sysc_pwrrdy_pwrseq_init(dev, regmap, match->data);
> > +	if (ret)
> > +		return ret;
> 
> Honestly I don't think this is worth a separate function, could have as well
> been:
> 
> 	if (match->data->soc_data->pwrrdy_pwrseq) {
> 		adev = ...
> 	}
> 
> But I won't die on that hill.

Ok, will fix this in next version.

Cheers,
Biju

> 
> Bart
> 
> > +
> >  	return of_syscon_register_regmap(dev->of_node, regmap);
> >  }
> >
> > diff --git a/drivers/soc/renesas/rz-sysc.h b/drivers/soc/renesas/rz-sysc.h
> > index 921ee0d26c47..e55f3258d703 100644
> > --- a/drivers/soc/renesas/rz-sysc.h
> > +++ b/drivers/soc/renesas/rz-sysc.h
> > @@ -20,6 +20,7 @@
> >   * @revision_mask: SYSC SoC ID revision mask
> >   * @specific_id_mask: SYSC SoC ID specific ID mask
> >   * @print_id: print SoC-specific extended device identification
> > + * @pwrrdy_pwrseq: has pwrrdy register controlled through power sequencer
> >   */
> >  struct rz_sysc_soc_id_init_data {
> >  	const char * const family;
> > @@ -29,6 +30,7 @@ struct rz_sysc_soc_id_init_data {
> >  	u32 specific_id_mask;
> >  	void (*print_id)(struct device *dev, void __iomem *sysc_base,
> >  			 struct soc_device_attribute *soc_dev_attr);
> > +	bool pwrrdy_pwrseq;
> >  };
> >
> >  /**
> > --
> > 2.43.0
> >
> >