Re: [PATCH v1] ACPI: bus: Drop two fields from struct acpi_device_pnp

From: Hans de Goede

Date: Mon Aug 31 2026 - 16:19:01 EST


Hi,

On 31-Aug-26 22:07, Rafael J. Wysocki wrote:
> From: "Rafael J. Wysocki" <rafael.j.wysocki@xxxxxxxxx>
>
> There are two fields in struct acpi_device_pnp, device_name and
> device_class, that were supposed to be populated and used by device
> drivers, but they have never been used consistently and now they
> are only set for the bus object in acpi_set_pnp_ids() (and never
> read afterward).
>
> Drop them along with all of the associated symbols except for
> MAX_ACPI_CLASS_NAME_LEN and the acpi_device_class typedef that
> are used by the ACPI netlink messaging code. Move those two
> definitions closer to the struct acpi_bus_event that refers to
> the acpi_device_class type.
>
> No intentional functional impact.
>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Nice :) Patch looks good to me:

Reviewed-by: Hans de Goede <johannes.goede@xxxxxxxxxxxxxxxx>

Regards,

Hans



> ---
> drivers/acpi/scan.c | 4 ----
> include/acpi/acpi_bus.h | 11 +++--------
> 2 files changed, 3 insertions(+), 12 deletions(-)
>
> --- a/drivers/acpi/scan.c
> +++ b/drivers/acpi/scan.c
> @@ -28,9 +28,7 @@
> #include "internal.h"
> #include "sleep.h"
>
> -#define ACPI_BUS_CLASS "system_bus"
> #define ACPI_BUS_HID "LNXSYBUS"
> -#define ACPI_BUS_DEVICE_NAME "System Bus"
>
> #define INVALID_ACPI_HANDLE ((acpi_handle)ZERO_PAGE(0))
>
> @@ -1446,8 +1444,6 @@ static void acpi_set_pnp_ids(acpi_handle
> acpi_object_is_system_bus(handle)) {
> /* \_SB, \_TZ, LNXSYBUS */
> acpi_add_id(pnp, ACPI_BUS_HID);
> - strscpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
> - strscpy(pnp->device_class, ACPI_BUS_CLASS);
> }
>
> break;
> --- a/include/acpi/acpi_bus.h
> +++ b/include/acpi/acpi_bus.h
> @@ -206,12 +206,8 @@ struct acpi_device_dir {
>
> /* Plug and Play */
>
> -#define MAX_ACPI_DEVICE_NAME_LEN 40
> -#define MAX_ACPI_CLASS_NAME_LEN 20
> typedef char acpi_bus_id[8];
> typedef u64 acpi_bus_address;
> -typedef char acpi_device_name[MAX_ACPI_DEVICE_NAME_LEN];
> -typedef char acpi_device_class[MAX_ACPI_CLASS_NAME_LEN];
>
> struct acpi_hardware_id {
> struct list_head list;
> @@ -233,16 +229,12 @@ struct acpi_device_pnp {
> acpi_bus_address bus_address; /* _ADR */
> char *unique_id; /* _UID */
> struct list_head ids; /* _HID and _CIDs */
> - acpi_device_name device_name; /* Driver-determined */
> - acpi_device_class device_class; /* " */
> };
>
> #define acpi_device_bid(d) ((d)->pnp.bus_id)
> #define acpi_device_adr(d) ((d)->pnp.bus_address)
> const char *acpi_device_hid(struct acpi_device *device);
> #define acpi_device_uid(d) ((d)->pnp.unique_id)
> -#define acpi_device_name(d) ((d)->pnp.device_name)
> -#define acpi_device_class(d) ((d)->pnp.device_class)
>
> /* Power Management */
>
> @@ -582,6 +574,9 @@ int acpi_dev_for_each_child_reverse(stru
> * ------
> */
>
> +#define MAX_ACPI_CLASS_NAME_LEN 20
> +typedef char acpi_device_class[MAX_ACPI_CLASS_NAME_LEN];
> +
> struct acpi_bus_event {
> struct list_head node;
> acpi_device_class device_class;
>
>
>