sonypi: Convert ACPI driver to a platform one

[PATCH v1] sonypi: Convert ACPI driver to a platform one

Posted by Rafael J. Wysocki 1 month, 1 week ago

From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>

In all cases in which a struct acpi_driver is used for binding a driver
to an ACPI device object, a corresponding platform device is created by
the ACPI core and that device is regarded as a proper representation of
underlying hardware.  Accordingly, a struct platform_driver should be
used by driver code to bind to that device.  There are multiple reasons
why drivers should not bind directly to ACPI device objects [1].

Overall, it is better to bind drivers to platform devices than to their
ACPI companions, so convert the sonypi ACPI 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.

Link: https://lore.kernel.org/all/2396510.ElGaqSPkdT@rafael.j.wysocki/ [1]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/char/sonypi.c | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/char/sonypi.c b/drivers/char/sonypi.c
index 677bb5ac950a..ccda997a9098 100644
--- a/drivers/char/sonypi.c
+++ b/drivers/char/sonypi.c
@@ -1115,15 +1115,17 @@ static int sonypi_disable(void)
 }
 
 #ifdef CONFIG_ACPI
-static int sonypi_acpi_add(struct acpi_device *device)
+static int sonypi_acpi_probe(struct platform_device *pdev)
 {
+	struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
+
 	sonypi_acpi_device = device;
 	strcpy(acpi_device_name(device), "Sony laptop hotkeys");
 	strcpy(acpi_device_class(device), "sony/hotkey");
 	return 0;
 }
 
-static void sonypi_acpi_remove(struct acpi_device *device)
+static void sonypi_acpi_remove(struct platform_device *pdev)
 {
 	sonypi_acpi_device = NULL;
 }
@@ -1133,13 +1135,12 @@ static const struct acpi_device_id sonypi_device_ids[] = {
 	{"", 0},
 };
 
-static struct acpi_driver sonypi_acpi_driver = {
-	.name           = "sonypi",
-	.class          = "hkey",
-	.ids            = sonypi_device_ids,
-	.ops            = {
-		           .add = sonypi_acpi_add,
-			   .remove = sonypi_acpi_remove,
+static struct platform_driver sonypi_acpi_driver = {
+	.probe = sonypi_acpi_probe,
+	.remove = sonypi_acpi_remove,
+	.driver = {
+		.name = "sonypi_acpi",
+		.acpi_match_table = sonypi_device_ids,
 	},
 };
 #endif
@@ -1518,8 +1519,8 @@ static int __init sonypi_init(void)
 		goto err_free_device;
 
 #ifdef CONFIG_ACPI
-	if (acpi_bus_register_driver(&sonypi_acpi_driver) >= 0)
-		acpi_driver_registered = 1;
+	error = platform_driver_register(&sonypi_acpi_driver);
+	acpi_driver_registered = !error;
 #endif
 
 	return 0;
@@ -1535,7 +1536,7 @@ static void __exit sonypi_exit(void)
 {
 #ifdef CONFIG_ACPI
 	if (acpi_driver_registered)
-		acpi_bus_unregister_driver(&sonypi_acpi_driver);
+		platform_driver_unregister(&sonypi_acpi_driver);
 #endif
 	platform_device_unregister(sonypi_platform_device);
 	platform_driver_unregister(&sonypi_driver);
-- 
2.51.0

Re: [PATCH v1] sonypi: Convert ACPI driver to a platform one

Posted by Rafael J. Wysocki 3 weeks, 1 day ago

On Mon, Feb 23, 2026 at 4:59 PM Rafael J. Wysocki <rafael@kernel.org> wrote:
>
> From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
>
> In all cases in which a struct acpi_driver is used for binding a driver
> to an ACPI device object, a corresponding platform device is created by
> the ACPI core and that device is regarded as a proper representation of
> underlying hardware.  Accordingly, a struct platform_driver should be
> used by driver code to bind to that device.  There are multiple reasons
> why drivers should not bind directly to ACPI device objects [1].
>
> Overall, it is better to bind drivers to platform devices than to their
> ACPI companions, so convert the sonypi ACPI 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.
>
> Link: https://lore.kernel.org/all/2396510.ElGaqSPkdT@rafael.j.wysocki/ [1]
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> ---
>  drivers/char/sonypi.c | 25 +++++++++++++------------
>  1 file changed, 13 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/char/sonypi.c b/drivers/char/sonypi.c
> index 677bb5ac950a..ccda997a9098 100644
> --- a/drivers/char/sonypi.c
> +++ b/drivers/char/sonypi.c
> @@ -1115,15 +1115,17 @@ static int sonypi_disable(void)
>  }
>
>  #ifdef CONFIG_ACPI
> -static int sonypi_acpi_add(struct acpi_device *device)
> +static int sonypi_acpi_probe(struct platform_device *pdev)
>  {
> +       struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
> +
>         sonypi_acpi_device = device;
>         strcpy(acpi_device_name(device), "Sony laptop hotkeys");
>         strcpy(acpi_device_class(device), "sony/hotkey");
>         return 0;
>  }
>
> -static void sonypi_acpi_remove(struct acpi_device *device)
> +static void sonypi_acpi_remove(struct platform_device *pdev)
>  {
>         sonypi_acpi_device = NULL;
>  }
> @@ -1133,13 +1135,12 @@ static const struct acpi_device_id sonypi_device_ids[] = {
>         {"", 0},
>  };
>
> -static struct acpi_driver sonypi_acpi_driver = {
> -       .name           = "sonypi",
> -       .class          = "hkey",
> -       .ids            = sonypi_device_ids,
> -       .ops            = {
> -                          .add = sonypi_acpi_add,
> -                          .remove = sonypi_acpi_remove,
> +static struct platform_driver sonypi_acpi_driver = {
> +       .probe = sonypi_acpi_probe,
> +       .remove = sonypi_acpi_remove,
> +       .driver = {
> +               .name = "sonypi_acpi",
> +               .acpi_match_table = sonypi_device_ids,
>         },
>  };
>  #endif
> @@ -1518,8 +1519,8 @@ static int __init sonypi_init(void)
>                 goto err_free_device;
>
>  #ifdef CONFIG_ACPI
> -       if (acpi_bus_register_driver(&sonypi_acpi_driver) >= 0)
> -               acpi_driver_registered = 1;
> +       error = platform_driver_register(&sonypi_acpi_driver);
> +       acpi_driver_registered = !error;
>  #endif
>
>         return 0;
> @@ -1535,7 +1536,7 @@ static void __exit sonypi_exit(void)
>  {
>  #ifdef CONFIG_ACPI
>         if (acpi_driver_registered)
> -               acpi_bus_unregister_driver(&sonypi_acpi_driver);
> +               platform_driver_unregister(&sonypi_acpi_driver);
>  #endif
>         platform_device_unregister(sonypi_platform_device);
>         platform_driver_unregister(&sonypi_driver);
> --


If anyone has any objections or  concerns regarding this change,
please let me know.

In the absence of any, I'll queue it up for 7.1.

Thanks!

Re: [PATCH v1] sonypi: Convert ACPI driver to a platform one

Posted by Ilpo Järvinen 2 weeks, 5 days ago

On Fri, 13 Mar 2026, Rafael J. Wysocki wrote:

> On Mon, Feb 23, 2026 at 4:59 PM Rafael J. Wysocki <rafael@kernel.org> wrote:
> >
> > From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
> >
> > In all cases in which a struct acpi_driver is used for binding a driver
> > to an ACPI device object, a corresponding platform device is created by
> > the ACPI core and that device is regarded as a proper representation of
> > underlying hardware.  Accordingly, a struct platform_driver should be
> > used by driver code to bind to that device.  There are multiple reasons
> > why drivers should not bind directly to ACPI device objects [1].
> >
> > Overall, it is better to bind drivers to platform devices than to their
> > ACPI companions, so convert the sonypi ACPI 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.
> >
> > Link: https://lore.kernel.org/all/2396510.ElGaqSPkdT@rafael.j.wysocki/ [1]
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > ---
> >  drivers/char/sonypi.c | 25 +++++++++++++------------
> >  1 file changed, 13 insertions(+), 12 deletions(-)
> >
> > diff --git a/drivers/char/sonypi.c b/drivers/char/sonypi.c
> > index 677bb5ac950a..ccda997a9098 100644
> > --- a/drivers/char/sonypi.c
> > +++ b/drivers/char/sonypi.c
> > @@ -1115,15 +1115,17 @@ static int sonypi_disable(void)
> >  }
> >
> >  #ifdef CONFIG_ACPI
> > -static int sonypi_acpi_add(struct acpi_device *device)
> > +static int sonypi_acpi_probe(struct platform_device *pdev)
> >  {
> > +       struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
> > +
> >         sonypi_acpi_device = device;
> >         strcpy(acpi_device_name(device), "Sony laptop hotkeys");
> >         strcpy(acpi_device_class(device), "sony/hotkey");
> >         return 0;
> >  }
> >
> > -static void sonypi_acpi_remove(struct acpi_device *device)
> > +static void sonypi_acpi_remove(struct platform_device *pdev)
> >  {
> >         sonypi_acpi_device = NULL;
> >  }
> > @@ -1133,13 +1135,12 @@ static const struct acpi_device_id sonypi_device_ids[] = {
> >         {"", 0},
> >  };
> >
> > -static struct acpi_driver sonypi_acpi_driver = {
> > -       .name           = "sonypi",
> > -       .class          = "hkey",
> > -       .ids            = sonypi_device_ids,
> > -       .ops            = {
> > -                          .add = sonypi_acpi_add,
> > -                          .remove = sonypi_acpi_remove,
> > +static struct platform_driver sonypi_acpi_driver = {
> > +       .probe = sonypi_acpi_probe,
> > +       .remove = sonypi_acpi_remove,
> > +       .driver = {
> > +               .name = "sonypi_acpi",
> > +               .acpi_match_table = sonypi_device_ids,
> >         },
> >  };
> >  #endif
> > @@ -1518,8 +1519,8 @@ static int __init sonypi_init(void)
> >                 goto err_free_device;
> >
> >  #ifdef CONFIG_ACPI
> > -       if (acpi_bus_register_driver(&sonypi_acpi_driver) >= 0)
> > -               acpi_driver_registered = 1;
> > +       error = platform_driver_register(&sonypi_acpi_driver);
> > +       acpi_driver_registered = !error;
> >  #endif
> >
> >         return 0;
> > @@ -1535,7 +1536,7 @@ static void __exit sonypi_exit(void)
> >  {
> >  #ifdef CONFIG_ACPI
> >         if (acpi_driver_registered)
> > -               acpi_bus_unregister_driver(&sonypi_acpi_driver);
> > +               platform_driver_unregister(&sonypi_acpi_driver);
> >  #endif
> >         platform_device_unregister(sonypi_platform_device);
> >         platform_driver_unregister(&sonypi_driver);
> > --
> 
> 
> If anyone has any objections or  concerns regarding this change,
> please let me know.
> 
> In the absence of any, I'll queue it up for 7.1.

I did check it earlier, it seemed fine to me.

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>


-- 
 i.