Re: [PATCH RESEND v27 2/3] reset: npcm: register npcm8xx clock auxiliary bus device

[Philipp Zabel]

On Do, 2024-08-15 at 18:02 +0300, Tomer Maimon 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@xxxxxxxxx>
> Tested-by: Benjamin Fair <benjaminfair@xxxxxxxxxx>
> ---
>  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 100755 include/soc/nuvoton/clock-npcm8xx.h
> 
> diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
> index 67bce340a87e..c6bf5275cca2 100644
> --- a/drivers/reset/Kconfig
> +++ b/drivers/reset/Kconfig
> @@ -157,6 +157,7 @@ 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:

Here ret is ignored, which may be the return value from
register_restart_handler() above.

> +		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 100755
> 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)

Could you make this an inline function instead?

With those two issues addressed,

Reviewed-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>

regards
Philipp