[PATCH v26 2/3] reset: npcm: register npcm8xx clock auxiliary bus device

[Tomer Maimon]

Hi Benjamin,

Highly appreciated!

Thanks a lot

Tomer

On Thu, 11 Jul 2024 at 21:13, Benjamin Fair <benjaminfair at google.com> wrote:
>
> On Tue, 2 Jul 2024 at 12:17, Tomer Maimon <tmaimon77 at gmail.com> wrote:
> >
> > Add NPCM8xx clock controller auxiliary bus device registration.
> >
> > The NPCM8xx clock controller is registered as an aux device because the
> > reset and the clock controller share the same register region.
> >
> > Signed-off-by: Tomer Maimon <tmaimon77 at gmail.com>
>
> I booted a kernel with this driver and verified that basic
> functionality works fine.
>
> Tested-by: Benjamin Fair <benjaminfair at google.com>
>
> > ---
> >  drivers/reset/Kconfig               |  1 +
> >  drivers/reset/reset-npcm.c          | 74 ++++++++++++++++++++++++++++-
> >  include/soc/nuvoton/clock-npcm8xx.h | 16 +++++++
> >  3 files changed, 90 insertions(+), 1 deletion(-)
> >  create mode 100644 include/soc/nuvoton/clock-npcm8xx.h
> >
> > diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
> > index 7112f5932609..31ec8795c105 100644
> > --- a/drivers/reset/Kconfig
> > +++ b/drivers/reset/Kconfig
> > @@ -148,6 +148,7 @@ config RESET_MESON_AUDIO_ARB
> >  config RESET_NPCM
> >         bool "NPCM BMC Reset Driver" if COMPILE_TEST
> >         default ARCH_NPCM
> > +       select AUXILIARY_BUS
> >         help
> >           This enables the reset controller driver for Nuvoton NPCM
> >           BMC SoCs.
> > diff --git a/drivers/reset/reset-npcm.c b/drivers/reset/reset-npcm.c
> > index 8935ef95a2d1..aa68b947226a 100644
> > --- a/drivers/reset/reset-npcm.c
> > +++ b/drivers/reset/reset-npcm.c
> > @@ -1,6 +1,7 @@
> >  // SPDX-License-Identifier: GPL-2.0
> >  // Copyright (c) 2019 Nuvoton Technology corporation.
> >
> > +#include <linux/auxiliary_bus.h>
> >  #include <linux/delay.h>
> >  #include <linux/err.h>
> >  #include <linux/io.h>
> > @@ -10,11 +11,14 @@
> >  #include <linux/property.h>
> >  #include <linux/reboot.h>
> >  #include <linux/reset-controller.h>
> > +#include <linux/slab.h>
> >  #include <linux/spinlock.h>
> >  #include <linux/mfd/syscon.h>
> >  #include <linux/regmap.h>
> >  #include <linux/of_address.h>
> >
> > +#include <soc/nuvoton/clock-npcm8xx.h>
> > +
> >  /* NPCM7xx GCR registers */
> >  #define NPCM_MDLR_OFFSET       0x7C
> >  #define NPCM7XX_MDLR_USBD0     BIT(9)
> > @@ -89,6 +93,7 @@ struct npcm_rc_data {
> >         const struct npcm_reset_info *info;
> >         struct regmap *gcr_regmap;
> >         u32 sw_reset_number;
> > +       struct device *dev;
> >         void __iomem *base;
> >         spinlock_t lock;
> >  };
> > @@ -372,6 +377,67 @@ static const struct reset_control_ops npcm_rc_ops = {
> >         .status         = npcm_rc_status,
> >  };
> >
> > +static void npcm_clock_unregister_adev(void *_adev)
> > +{
> > +       struct auxiliary_device *adev = _adev;
> > +
> > +       auxiliary_device_delete(adev);
> > +       auxiliary_device_uninit(adev);
> > +}
> > +
> > +static void npcm_clock_adev_release(struct device *dev)
> > +{
> > +       struct auxiliary_device *adev = to_auxiliary_dev(dev);
> > +       struct npcm_clock_adev *rdev = to_npcm_clock_adev(adev);
> > +
> > +       kfree(rdev);
> > +}
> > +
> > +static struct auxiliary_device *npcm_clock_adev_alloc(struct npcm_rc_data *rst_data, char *clk_name)
> > +{
> > +       struct npcm_clock_adev *rdev;
> > +       struct auxiliary_device *adev;
> > +       int ret;
> > +
> > +       rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
> > +       if (!rdev)
> > +               return ERR_PTR(-ENOMEM);
> > +
> > +       rdev->base = rst_data->base;
> > +
> > +       adev = &rdev->adev;
> > +       adev->name = clk_name;
> > +       adev->dev.parent = rst_data->dev;
> > +       adev->dev.release = npcm_clock_adev_release;
> > +       adev->id = 555u;
> > +
> > +       ret = auxiliary_device_init(adev);
> > +       if (ret) {
> > +               kfree(rdev);
> > +               return ERR_PTR(ret);
> > +       }
> > +
> > +       return adev;
> > +}
> > +
> > +static int npcm8xx_clock_controller_register(struct npcm_rc_data *rst_data, char *clk_name)
> > +{
> > +       struct auxiliary_device *adev;
> > +       int ret;
> > +
> > +       adev = npcm_clock_adev_alloc(rst_data, clk_name);
> > +       if (IS_ERR(adev))
> > +               return PTR_ERR(adev);
> > +
> > +       ret = auxiliary_device_add(adev);
> > +       if (ret) {
> > +               auxiliary_device_uninit(adev);
> > +               return ret;
> > +       }
> > +
> > +       return devm_add_action_or_reset(rst_data->dev, npcm_clock_unregister_adev, adev);
> > +}
> > +
> >  static int npcm_rc_probe(struct platform_device *pdev)
> >  {
> >         struct npcm_rc_data *rc;
> > @@ -392,6 +458,7 @@ static int npcm_rc_probe(struct platform_device *pdev)
> >         rc->rcdev.of_node = pdev->dev.of_node;
> >         rc->rcdev.of_reset_n_cells = 2;
> >         rc->rcdev.of_xlate = npcm_reset_xlate;
> > +       rc->dev = &pdev->dev;
> >
> >         ret = devm_reset_controller_register(&pdev->dev, &rc->rcdev);
> >         if (ret) {
> > @@ -413,7 +480,12 @@ static int npcm_rc_probe(struct platform_device *pdev)
> >                 }
> >         }
> >
> > -       return ret;
> > +       switch (rc->info->bmc_id) {
> > +       case BMC_NPCM8XX:
> > +               return npcm8xx_clock_controller_register(rc, "clk-npcm8xx");
> > +       default:
> > +               return ret;
> > +       }
> >  }
> >
> >  static struct platform_driver npcm_rc_driver = {
> > diff --git a/include/soc/nuvoton/clock-npcm8xx.h b/include/soc/nuvoton/clock-npcm8xx.h
> > new file mode 100644
> > index 000000000000..139130e98c51
> > --- /dev/null
> > +++ b/include/soc/nuvoton/clock-npcm8xx.h
> > @@ -0,0 +1,16 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +#ifndef __SOC_NPCM8XX_CLOCK_H
> > +#define __SOC_NPCM8XX_CLOCK_H
> > +
> > +#include <linux/auxiliary_bus.h>
> > +#include <linux/container_of.h>
> > +
> > +struct npcm_clock_adev {
> > +       void __iomem *base;
> > +       struct auxiliary_device adev;
> > +};
> > +
> > +#define to_npcm_clock_adev(_adev) \
> > +       container_of((_adev), struct npcm_clock_adev, adev)
> > +
> > +#endif
> > --
> > 2.34.1
> >