On Thu, Dec 11, 2025 at 03:22:00PM +0100, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <[email protected]>
> 
> While binding drivers directly to struct acpi_device objects allows
> basic functionality to be provided, at least in the majority of cases,
> there are some problems with it, related to general consistency, sysfs
> layout, power management operation ordering, and code cleanliness.
> 
> Overall, it is better to bind drivers to platform devices than to their
> ACPI companions, so convert the ACPI NFIT core driver to a platform one.
> 
> While this is not expected to alter functionality, it changes sysfs
> layout and so it will be visible to user space.

Changes sysfs layout? That means it changes sysfs paths?
Does it change paths defined in Documentation/ABI/testing/sysfs "What:"


> 
> This change was mostly developed by Michal Wilczynski [1].
> 
> Linu: 
> https://lore.kernel.org/linux-acpi/[email protected]/
>  [1]
> Signed-off-by: Rafael J. Wysocki <[email protected]>
> ---
>  drivers/acpi/nfit/core.c |   34 ++++++++++++++++++----------------
>  1 file changed, 18 insertions(+), 16 deletions(-)
> 
> --- a/drivers/acpi/nfit/core.c
> +++ b/drivers/acpi/nfit/core.c
> @@ -2,6 +2,7 @@
>  /*
>   * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
>   */
> +#include <linux/platform_device.h>
>  #include <linux/list_sort.h>
>  #include <linux/libnvdimm.h>
>  #include <linux/module.h>
> @@ -98,7 +99,7 @@ static struct acpi_device *to_acpi_dev(s
>                       || strcmp(nd_desc->provider_name, "ACPI.NFIT") != 0)
>               return NULL;
>  
> -     return to_acpi_device(acpi_desc->dev);
> +     return ACPI_COMPANION(acpi_desc->dev);
>  }
>  
>  static int xlat_bus_status(void *buf, unsigned int cmd, u32 status)
> @@ -3283,11 +3284,11 @@ static void acpi_nfit_put_table(void *ta
>  
>  static void acpi_nfit_notify(acpi_handle handle, u32 event, void *data)
>  {
> -     struct acpi_device *adev = data;
> +     struct device *dev = data;
>  
> -     device_lock(&adev->dev);
> -     __acpi_nfit_notify(&adev->dev, handle, event);
> -     device_unlock(&adev->dev);
> +     device_lock(dev);
> +     __acpi_nfit_notify(dev, handle, event);
> +     device_unlock(dev);
>  }
>  
>  static void acpi_nfit_remove_notify_handler(void *data)
> @@ -3328,18 +3329,19 @@ void acpi_nfit_shutdown(void *data)
>  }
>  EXPORT_SYMBOL_GPL(acpi_nfit_shutdown);
>  
> -static int acpi_nfit_add(struct acpi_device *adev)
> +static int acpi_nfit_probe(struct platform_device *pdev)
>  {
>       struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
>       struct acpi_nfit_desc *acpi_desc;
> -     struct device *dev = &adev->dev;
> +     struct device *dev = &pdev->dev;
> +     struct acpi_device *adev = ACPI_COMPANION(dev);
>       struct acpi_table_header *tbl;
>       acpi_status status = AE_OK;
>       acpi_size sz;
>       int rc = 0;
>  
>       rc = acpi_dev_install_notify_handler(adev, ACPI_DEVICE_NOTIFY,
> -                                          acpi_nfit_notify, adev);
> +                                          acpi_nfit_notify, dev);
>       if (rc)
>               return rc;
>  
> @@ -3369,7 +3371,7 @@ static int acpi_nfit_add(struct acpi_dev
>       acpi_desc = devm_kzalloc(dev, sizeof(*acpi_desc), GFP_KERNEL);
>       if (!acpi_desc)
>               return -ENOMEM;
> -     acpi_nfit_desc_init(acpi_desc, &adev->dev);
> +     acpi_nfit_desc_init(acpi_desc, dev);
>  
>       /* Save the acpi header for exporting the revision via sysfs */
>       acpi_desc->acpi_header = *tbl;
> @@ -3474,11 +3476,11 @@ static const struct acpi_device_id acpi_
>  };
>  MODULE_DEVICE_TABLE(acpi, acpi_nfit_ids);
>  
> -static struct acpi_driver acpi_nfit_driver = {
> -     .name = KBUILD_MODNAME,
> -     .ids = acpi_nfit_ids,
> -     .ops = {
> -             .add = acpi_nfit_add,
> +static struct platform_driver acpi_nfit_driver = {
> +     .probe = acpi_nfit_probe,
> +     .driver = {
> +             .name = "acpi-nfit",
> +             .acpi_match_table = acpi_nfit_ids,
>       },
>  };
>  
> @@ -3516,7 +3518,7 @@ static __init int nfit_init(void)
>               return -ENOMEM;
>  
>       nfit_mce_register();
> -     ret = acpi_bus_register_driver(&acpi_nfit_driver);
> +     ret = platform_driver_register(&acpi_nfit_driver);
>       if (ret) {
>               nfit_mce_unregister();
>               destroy_workqueue(nfit_wq);
> @@ -3529,7 +3531,7 @@ static __init int nfit_init(void)
>  static __exit void nfit_exit(void)
>  {
>       nfit_mce_unregister();
> -     acpi_bus_unregister_driver(&acpi_nfit_driver);
> +     platform_driver_unregister(&acpi_nfit_driver);
>       destroy_workqueue(nfit_wq);
>       WARN_ON(!list_empty(&acpi_descs));
>  }
> 
> 
> 
> 

Reply via email to