[PATCH v2 2/3] mfd: syscon: Remove the platform driver support

[Liviu Dudau]

On Tue, Dec 17, 2024 at 12:11:41PM -0600, Rob Herring (Arm) wrote:
> The platform driver is dead code. It is not used by DT platforms since
> commit bdb0066df96e ("mfd: syscon: Decouple syscon interface from
> platform devices") which said:
> 
>     For non-DT based platforms, this patch keeps syscon platform driver
>     structure so that syscon can be probed and such non-DT based drivers
>     can use syscon_regmap_lookup_by_pdev API and access regmap handles.
>     Once all users of "syscon_regmap_lookup_by_pdev" migrated to DT based,
>     we can completely remove platform driver of syscon, and keep only helper
>     functions to get regmap handles.
> 
> The last user of syscon_regmap_lookup_by_pdevname() was removed in 2018.
> syscon_regmap_lookup_by_pdevname() was then removed in 2019, but that
> commit failed to remove the rest of the platform driver.
> 
> Tested-by: Krzysztof Kozlowski <krzysztof.kozlowski at linaro.org>
> Signed-off-by: Rob Herring (Arm) <robh at kernel.org>

(Mostly for the vexpress-sysreg.c part, but hey, it's all code being removed):

Acked-by: Liviu Dudau <liviu.dudau at arm.com>

Best regards,
Liviu

> ---
>  drivers/mfd/syscon.c                 | 66 ------------------------------------
>  drivers/mfd/vexpress-sysreg.c        |  1 -
>  include/linux/platform_data/syscon.h |  9 -----
>  3 files changed, 76 deletions(-)
> 
> diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
> index 72f20de9652da2d7bad12e4bc2c43ac0c9a97f76..bfb1f69fcff1d3cd35cf04ccd4c449e7d0395c79 100644
> --- a/drivers/mfd/syscon.c
> +++ b/drivers/mfd/syscon.c
> @@ -12,22 +12,15 @@
>  #include <linux/clk.h>
>  #include <linux/err.h>
>  #include <linux/hwspinlock.h>
> -#include <linux/io.h>
> -#include <linux/init.h>
>  #include <linux/list.h>
>  #include <linux/mutex.h>
>  #include <linux/of.h>
>  #include <linux/of_address.h>
> -#include <linux/of_platform.h>
> -#include <linux/platform_data/syscon.h>
> -#include <linux/platform_device.h>
>  #include <linux/regmap.h>
>  #include <linux/reset.h>
>  #include <linux/mfd/syscon.h>
>  #include <linux/slab.h>
>  
> -static struct platform_driver syscon_driver;
> -
>  static DEFINE_MUTEX(syscon_list_lock);
>  static LIST_HEAD(syscon_list);
>  
> @@ -337,62 +330,3 @@ struct regmap *syscon_regmap_lookup_by_phandle_optional(struct device_node *np,
>  	return regmap;
>  }
>  EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle_optional);
> -
> -static int syscon_probe(struct platform_device *pdev)
> -{
> -	struct device *dev = &pdev->dev;
> -	struct syscon_platform_data *pdata = dev_get_platdata(dev);
> -	struct syscon *syscon;
> -	struct regmap_config syscon_config = syscon_regmap_config;
> -	struct resource *res;
> -	void __iomem *base;
> -
> -	syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL);
> -	if (!syscon)
> -		return -ENOMEM;
> -
> -	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -	if (!res)
> -		return -ENOENT;
> -
> -	base = devm_ioremap(dev, res->start, resource_size(res));
> -	if (!base)
> -		return -ENOMEM;
> -
> -	syscon_config.max_register = resource_size(res) - 4;
> -	if (!syscon_config.max_register)
> -		syscon_config.max_register_is_0 = true;
> -
> -	if (pdata)
> -		syscon_config.name = pdata->label;
> -	syscon->regmap = devm_regmap_init_mmio(dev, base, &syscon_config);
> -	if (IS_ERR(syscon->regmap)) {
> -		dev_err(dev, "regmap init failed\n");
> -		return PTR_ERR(syscon->regmap);
> -	}
> -
> -	platform_set_drvdata(pdev, syscon);
> -
> -	dev_dbg(dev, "regmap %pR registered\n", res);
> -
> -	return 0;
> -}
> -
> -static const struct platform_device_id syscon_ids[] = {
> -	{ "syscon", },
> -	{ }
> -};
> -
> -static struct platform_driver syscon_driver = {
> -	.driver = {
> -		.name = "syscon",
> -	},
> -	.probe		= syscon_probe,
> -	.id_table	= syscon_ids,
> -};
> -
> -static int __init syscon_init(void)
> -{
> -	return platform_driver_register(&syscon_driver);
> -}
> -postcore_initcall(syscon_init);
> diff --git a/drivers/mfd/vexpress-sysreg.c b/drivers/mfd/vexpress-sysreg.c
> index d34d58ce46db2ad0d53b3daeabc9d3763883b39a..ef03d6cec9ff6927668d051ca459eb1d8ff7269e 100644
> --- a/drivers/mfd/vexpress-sysreg.c
> +++ b/drivers/mfd/vexpress-sysreg.c
> @@ -10,7 +10,6 @@
>  #include <linux/mfd/core.h>
>  #include <linux/module.h>
>  #include <linux/of_platform.h>
> -#include <linux/platform_data/syscon.h>
>  #include <linux/platform_device.h>
>  #include <linux/slab.h>
>  #include <linux/stat.h>
> diff --git a/include/linux/platform_data/syscon.h b/include/linux/platform_data/syscon.h
> deleted file mode 100644
> index 2c089dd3e2bda3baf5cef201ef43bca709e12c0b..0000000000000000000000000000000000000000
> --- a/include/linux/platform_data/syscon.h
> +++ /dev/null
> @@ -1,9 +0,0 @@
> -/* SPDX-License-Identifier: GPL-2.0 */
> -#ifndef PLATFORM_DATA_SYSCON_H
> -#define PLATFORM_DATA_SYSCON_H
> -
> -struct syscon_platform_data {
> -	const char *label;
> -};
> -
> -#endif
> 
> -- 
> 2.45.2
> 

-- 
====================
| I would like to |
| fix the world,  |
| but they're not |
| giving me the   |
 \ source code!  /
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