Re: [PATCH v5 8/9] reset: amlogic: split the device core and platform probe

[Neil Armstrong]

On 10/09/2024 18:32, Jerome Brunet wrote:
> To prepare the addition of the auxiliary device support, split
> out the device coomon functions from the probe of the platform device.
>
> The device core function will be common to both the platform and auxiliary
> driver.
>
> Signed-off-by: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
> ---
>   drivers/reset/amlogic/Kconfig              |   7 +-
>   drivers/reset/amlogic/Makefile             |   1 +
>   drivers/reset/amlogic/reset-meson-common.c | 121 ++++++++++++++++++++++++++++
>   drivers/reset/amlogic/reset-meson.c        | 122 ++++-------------------------
>   drivers/reset/amlogic/reset-meson.h        |  24 ++++++
>   5 files changed, 167 insertions(+), 108 deletions(-)
>
> diff --git a/drivers/reset/amlogic/Kconfig b/drivers/reset/amlogic/Kconfig
> index 532e6a4f7865..1d77987088f4 100644
> --- a/drivers/reset/amlogic/Kconfig
> +++ b/drivers/reset/amlogic/Kconfig
> @@ -1,10 +1,15 @@
> +config RESET_MESON_COMMON
> +	tristate
> +	select REGMAP
> +
>   config RESET_MESON
>   	tristate "Meson Reset Driver"
>   	depends on ARCH_MESON || COMPILE_TEST
>   	default ARCH_MESON
>   	select REGMAP_MMIO
> +	select RESET_MESON_COMMON
>   	help
> -	  This enables the reset driver for Amlogic Meson SoCs.
> +	  This enables the reset driver for Amlogic SoCs.
>   
>   config RESET_MESON_AUDIO_ARB
>   	tristate "Meson Audio Memory Arbiter Reset Driver"
> diff --git a/drivers/reset/amlogic/Makefile b/drivers/reset/amlogic/Makefile
> index 55509fc78513..74aaa2fb5e13 100644
> --- a/drivers/reset/amlogic/Makefile
> +++ b/drivers/reset/amlogic/Makefile
> @@ -1,2 +1,3 @@
>   obj-$(CONFIG_RESET_MESON) += reset-meson.o
> +obj-$(CONFIG_RESET_MESON_COMMON) += reset-meson-common.o
>   obj-$(CONFIG_RESET_MESON_AUDIO_ARB) += reset-meson-audio-arb.o
> diff --git a/drivers/reset/amlogic/reset-meson-common.c b/drivers/reset/amlogic/reset-meson-common.c
> new file mode 100644
> index 000000000000..d57544801ae9
> --- /dev/null
> +++ b/drivers/reset/amlogic/reset-meson-common.c
> @@ -0,0 +1,121 @@
> +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
> +/*
> + * Amlogic Meson Reset core functions
> + *
> + * Copyright (c) 2016-2024 BayLibre, SAS.
> + * Authors: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> + *          Jerome Brunet <jbrunet@xxxxxxxxxxxx>
> + */
> +
> +#include <linux/device.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/reset-controller.h>
> +
> +#include "reset-meson.h"
> +
> +struct meson_reset {
> +	const struct meson_reset_param *param;
> +	struct reset_controller_dev rcdev;
> +	struct regmap *map;
> +};
> +
> +static void meson_reset_offset_and_bit(struct meson_reset *data,
> +				       unsigned long id,
> +				       unsigned int *offset,
> +				       unsigned int *bit)
> +{
> +	unsigned int stride = regmap_get_reg_stride(data->map);
> +
> +	*offset = (id / (stride * BITS_PER_BYTE)) * stride;
> +	*bit = id % (stride * BITS_PER_BYTE);
> +}
> +
> +static int meson_reset_reset(struct reset_controller_dev *rcdev,
> +			     unsigned long id)
> +{
> +	struct meson_reset *data =
> +		container_of(rcdev, struct meson_reset, rcdev);
> +	unsigned int offset, bit;
> +
> +	meson_reset_offset_and_bit(data, id, &offset, &bit);
> +	offset += data->param->reset_offset;
> +
> +	return regmap_write(data->map, offset, BIT(bit));
> +}
> +
> +static int meson_reset_level(struct reset_controller_dev *rcdev,
> +			    unsigned long id, bool assert)
> +{
> +	struct meson_reset *data =
> +		container_of(rcdev, struct meson_reset, rcdev);
> +	unsigned int offset, bit;
> +
> +	meson_reset_offset_and_bit(data, id, &offset, &bit);
> +	offset += data->param->level_offset;
> +	assert ^= data->param->level_low_reset;
> +
> +	return regmap_update_bits(data->map, offset,
> +				  BIT(bit), assert ? BIT(bit) : 0);
> +}
> +
> +static int meson_reset_status(struct reset_controller_dev *rcdev,
> +			      unsigned long id)
> +{
> +	struct meson_reset *data =
> +		container_of(rcdev, struct meson_reset, rcdev);
> +	unsigned int val, offset, bit;
> +
> +	meson_reset_offset_and_bit(data, id, &offset, &bit);
> +	offset += data->param->level_offset;
> +
> +	regmap_read(data->map, offset, &val);
> +	val = !!(BIT(bit) & val);
> +
> +	return val ^ data->param->level_low_reset;
> +}
> +
> +static int meson_reset_assert(struct reset_controller_dev *rcdev,
> +			      unsigned long id)
> +{
> +	return meson_reset_level(rcdev, id, true);
> +}
> +
> +static int meson_reset_deassert(struct reset_controller_dev *rcdev,
> +				unsigned long id)
> +{
> +	return meson_reset_level(rcdev, id, false);
> +}
> +
> +static const struct reset_control_ops meson_reset_ops = {
> +	.reset		= meson_reset_reset,
> +	.assert		= meson_reset_assert,
> +	.deassert	= meson_reset_deassert,
> +	.status		= meson_reset_status,
> +};
> +
> +int meson_reset_controller_register(struct device *dev, struct regmap *map,
> +				    const struct meson_reset_param *param)
> +{
> +	struct meson_reset *data;
> +
> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	data->param = param;
> +	data->map = map;
> +	data->rcdev.owner = dev->driver->owner;
> +	data->rcdev.nr_resets = param->reset_num;
> +	data->rcdev.ops = &meson_reset_ops;
> +	data->rcdev.of_node = dev->of_node;
> +
> +	return devm_reset_controller_register(dev, &data->rcdev);
> +}
> +EXPORT_SYMBOL_NS_GPL(meson_reset_controller_register, MESON_RESET);
> +
> +MODULE_DESCRIPTION("Amlogic Meson Reset Core function");
> +MODULE_AUTHOR("Neil Armstrong <narmstrong@xxxxxxxxxxxx>");
> +MODULE_AUTHOR("Jerome Brunet <jbrunet@xxxxxxxxxxxx>");
> +MODULE_LICENSE("Dual BSD/GPL");
> +MODULE_IMPORT_NS(MESON_RESET);
> diff --git a/drivers/reset/amlogic/reset-meson.c b/drivers/reset/amlogic/reset-meson.c
> index af690d3012ec..feb19bf6da77 100644
> --- a/drivers/reset/amlogic/reset-meson.c
> +++ b/drivers/reset/amlogic/reset-meson.c
> @@ -2,106 +2,20 @@
>   /*
>    * Amlogic Meson Reset Controller driver
>    *
> - * Copyright (c) 2016 BayLibre, SAS.
> - * Author: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> + * Copyright (c) 2016-2024 BayLibre, SAS.
> + * Authors: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> + *          Jerome Brunet <jbrunet@xxxxxxxxxxxx>
>    */
> +
>   #include <linux/err.h>
> -#include <linux/init.h>
>   #include <linux/io.h>
>   #include <linux/of.h>
>   #include <linux/module.h>
>   #include <linux/platform_device.h>
>   #include <linux/regmap.h>
>   #include <linux/reset-controller.h>
> -#include <linux/slab.h>
> -#include <linux/types.h>
> -
> -struct meson_reset_param {
> -	unsigned int reset_num;
> -	unsigned int reset_offset;
> -	unsigned int level_offset;
> -	bool level_low_reset;
> -};
> -
> -struct meson_reset {
> -	const struct meson_reset_param *param;
> -	struct reset_controller_dev rcdev;
> -	struct regmap *map;
> -};
> -
> -static void meson_reset_offset_and_bit(struct meson_reset *data,
> -				       unsigned long id,
> -				       unsigned int *offset,
> -				       unsigned int *bit)
> -{
> -	unsigned int stride = regmap_get_reg_stride(data->map);
> -
> -	*offset = (id / (stride * BITS_PER_BYTE)) * stride;
> -	*bit = id % (stride * BITS_PER_BYTE);
> -}
> -
> -static int meson_reset_reset(struct reset_controller_dev *rcdev,
> -			     unsigned long id)
> -{
> -	struct meson_reset *data =
> -		container_of(rcdev, struct meson_reset, rcdev);
> -	unsigned int offset, bit;
> -
> -	meson_reset_offset_and_bit(data, id, &offset, &bit);
> -	offset += data->param->reset_offset;
> -
> -	return regmap_write(data->map, offset, BIT(bit));
> -}
> -
> -static int meson_reset_level(struct reset_controller_dev *rcdev,
> -			    unsigned long id, bool assert)
> -{
> -	struct meson_reset *data =
> -		container_of(rcdev, struct meson_reset, rcdev);
> -	unsigned int offset, bit;
> -
> -	meson_reset_offset_and_bit(data, id, &offset, &bit);
> -	offset += data->param->level_offset;
> -	assert ^= data->param->level_low_reset;
>   
> -	return regmap_update_bits(data->map, offset,
> -				  BIT(bit), assert ? BIT(bit) : 0);
> -}
> -
> -static int meson_reset_status(struct reset_controller_dev *rcdev,
> -			      unsigned long id)
> -{
> -	struct meson_reset *data =
> -		container_of(rcdev, struct meson_reset, rcdev);
> -	unsigned int val, offset, bit;
> -
> -	meson_reset_offset_and_bit(data, id, &offset, &bit);
> -	offset += data->param->level_offset;
> -
> -	regmap_read(data->map, offset, &val);
> -	val = !!(BIT(bit) & val);
> -
> -	return val ^ data->param->level_low_reset;
> -}
> -
> -static int meson_reset_assert(struct reset_controller_dev *rcdev,
> -			      unsigned long id)
> -{
> -	return meson_reset_level(rcdev, id, true);
> -}
> -
> -static int meson_reset_deassert(struct reset_controller_dev *rcdev,
> -				unsigned long id)
> -{
> -	return meson_reset_level(rcdev, id, false);
> -}
> -
> -static const struct reset_control_ops meson_reset_ops = {
> -	.reset		= meson_reset_reset,
> -	.assert		= meson_reset_assert,
> -	.deassert	= meson_reset_deassert,
> -	.status		= meson_reset_status,
> -};
> +#include "reset-meson.h"
>   
>   static const struct meson_reset_param meson8b_param = {
>   	.reset_num	= 256,
> @@ -151,33 +65,25 @@ static const struct regmap_config regmap_config = {
>   
>   static int meson_reset_probe(struct platform_device *pdev)
>   {
> +	const struct meson_reset_param *param;
>   	struct device *dev = &pdev->dev;
> -	struct meson_reset *data;
> +	struct regmap *map;
>   	void __iomem *base;
>   
> -	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> -	if (!data)
> -		return -ENOMEM;
> -
>   	base = devm_platform_ioremap_resource(pdev, 0);
>   	if (IS_ERR(base))
>   		return PTR_ERR(base);
>   
> -	data->param = device_get_match_data(dev);
> -	if (!data->param)
> +	param = device_get_match_data(dev);
> +	if (!param)
>   		return -ENODEV;
>   
> -	data->map = devm_regmap_init_mmio(dev, base, &regmap_config);
> -	if (IS_ERR(data->map))
> -		return dev_err_probe(dev, PTR_ERR(data->map),
> +	map = devm_regmap_init_mmio(dev, base, &regmap_config);
> +	if (IS_ERR(map))
> +		return dev_err_probe(dev, PTR_ERR(map),
>   				     "can't init regmap mmio region\n");
>   
> -	data->rcdev.owner = THIS_MODULE;
> -	data->rcdev.nr_resets = data->param->reset_num;
> -	data->rcdev.ops = &meson_reset_ops;
> -	data->rcdev.of_node = dev->of_node;
> -
> -	return devm_reset_controller_register(dev, &data->rcdev);
> +	return meson_reset_controller_register(dev, map, param);
>   }
>   
>   static struct platform_driver meson_reset_driver = {
> @@ -191,4 +97,6 @@ module_platform_driver(meson_reset_driver);
>   
>   MODULE_DESCRIPTION("Amlogic Meson Reset Controller driver");
>   MODULE_AUTHOR("Neil Armstrong <narmstrong@xxxxxxxxxxxx>");
> +MODULE_AUTHOR("Jerome Brunet <jbrunet@xxxxxxxxxxxx>");
>   MODULE_LICENSE("Dual BSD/GPL");
> +MODULE_IMPORT_NS(MESON_RESET);
> diff --git a/drivers/reset/amlogic/reset-meson.h b/drivers/reset/amlogic/reset-meson.h
> new file mode 100644
> index 000000000000..4e1dbd7569c5
> --- /dev/null
> +++ b/drivers/reset/amlogic/reset-meson.h
> @@ -0,0 +1,24 @@
> +/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
> +/*
> + * Copyright (c) 2024 BayLibre, SAS.
> + * Author: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
> + */
> +
> +#ifndef __MESON_RESET_H
> +#define __MESON_RESET_H
> +
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/reset-controller.h>
> +
> +struct meson_reset_param {
> +	unsigned int reset_num;
> +	unsigned int reset_offset;
> +	unsigned int level_offset;
> +	bool level_low_reset;
> +};
> +
> +int meson_reset_controller_register(struct device *dev, struct regmap *map,
> +				    const struct meson_reset_param *param);
> +
> +#endif /* __MESON_RESET_H */

Reviewed-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>