[PATCH v2 4/8] ACPI: driver: Do not set acpi_device_name() unnecessarily
From: Rafael J. Wysocki
Date: Fri Mar 13 2026 - 09:08:34 EST
From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
ACPI drivers usually set acpi_device_name() for the given struct
acpi_device to whatever they like, but that value is never used unless
the driver itself uses it and, quite unfortunately, drivers neglect to
clear it on remove. Some drivers use it for printing messages or
initializing the names of subordinate devices, but it is better to use
string literals for that, especially if the given one is used just once.
To eliminate unnecessary overhead related to acpi_device_name()
handling, rework multiple core ACPI device drivers to stop setting
acpi_device_name() for struct acpi_device objects manipulated
by them and use a string literal instead of it where applicable.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/acpi/ac.c | 6 ++----
drivers/acpi/acpi_memhotplug.c | 2 --
drivers/acpi/acpi_pad.c | 2 --
drivers/acpi/acpi_processor.c | 1 -
drivers/acpi/acpi_video.c | 16 +++++-----------
drivers/acpi/battery.c | 3 ---
drivers/acpi/button.c | 7 +++----
drivers/acpi/ec.c | 2 --
drivers/acpi/pci_link.c | 2 --
drivers/acpi/pci_root.c | 7 ++-----
drivers/acpi/power.c | 2 --
drivers/acpi/sbs.c | 1 -
drivers/acpi/sbshc.c | 2 --
drivers/acpi/thermal.c | 6 ++----
include/acpi/processor.h | 1 -
15 files changed, 14 insertions(+), 46 deletions(-)
--- a/drivers/acpi/ac.c
+++ b/drivers/acpi/ac.c
@@ -22,7 +22,6 @@
#include <acpi/battery.h>
#define ACPI_AC_CLASS "ac_adapter"
-#define ACPI_AC_DEVICE_NAME "AC Adapter"
#define ACPI_AC_FILE_STATE "state"
#define ACPI_AC_NOTIFY_STATUS 0x80
#define ACPI_AC_STATUS_OFFLINE 0x00
@@ -203,7 +202,6 @@ static int acpi_ac_probe(struct platform
return -ENOMEM;
ac->device = adev;
- strscpy(acpi_device_name(adev), ACPI_AC_DEVICE_NAME);
strscpy(acpi_device_class(adev), ACPI_AC_CLASS);
platform_set_drvdata(pdev, ac);
@@ -226,8 +224,8 @@ static int acpi_ac_probe(struct platform
goto err_release_ac;
}
- pr_info("%s [%s] (%s-line)\n", acpi_device_name(adev),
- acpi_device_bid(adev), str_on_off(ac->state));
+ pr_info("AC Adapter [%s] (%s-line)\n", acpi_device_bid(adev),
+ str_on_off(ac->state));
ac->battery_nb.notifier_call = acpi_ac_battery_notify;
register_acpi_notifier(&ac->battery_nb);
--- a/drivers/acpi/acpi_memhotplug.c
+++ b/drivers/acpi/acpi_memhotplug.c
@@ -20,7 +20,6 @@
#define ACPI_MEMORY_DEVICE_CLASS "memory"
#define ACPI_MEMORY_DEVICE_HID "PNP0C80"
-#define ACPI_MEMORY_DEVICE_NAME "Hotplug Mem Device"
static const struct acpi_device_id memory_device_ids[] = {
{ACPI_MEMORY_DEVICE_HID, 0},
@@ -297,7 +296,6 @@ static int acpi_memory_device_add(struct
INIT_LIST_HEAD(&mem_device->res_list);
mem_device->device = device;
mem_device->mgid = -1;
- sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
device->driver_data = mem_device;
--- a/drivers/acpi/acpi_pad.c
+++ b/drivers/acpi/acpi_pad.c
@@ -24,7 +24,6 @@
#include <xen/xen.h>
#define ACPI_PROCESSOR_AGGREGATOR_CLASS "acpi_pad"
-#define ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME "Processor Aggregator"
#define ACPI_PROCESSOR_AGGREGATOR_NOTIFY 0x80
#define ACPI_PROCESSOR_AGGREGATOR_STATUS_SUCCESS 0
@@ -427,7 +426,6 @@ static int acpi_pad_probe(struct platfor
{
struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
- strscpy(acpi_device_name(adev), ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME);
strscpy(acpi_device_class(adev), ACPI_PROCESSOR_AGGREGATOR_CLASS);
return acpi_dev_install_notify_handler(adev, ACPI_DEVICE_NOTIFY,
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -438,7 +438,6 @@ static int acpi_processor_add(struct acp
}
pr->handle = device->handle;
- strscpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
strscpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
device->driver_data = pr;
--- a/drivers/acpi/acpi_video.c
+++ b/drivers/acpi/acpi_video.c
@@ -30,9 +30,6 @@
#include <linux/uaccess.h>
#include <linux/string_choices.h>
-#define ACPI_VIDEO_BUS_NAME "Video Bus"
-#define ACPI_VIDEO_DEVICE_NAME "Video Device"
-
#define MAX_NAME_LEN 20
MODULE_AUTHOR("Bruno Ducrot");
@@ -1144,7 +1141,6 @@ static int acpi_video_bus_get_one_device
return -ENOMEM;
}
- strscpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
strscpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
data->device_id = device_id;
@@ -1882,7 +1878,7 @@ static int acpi_video_bus_add_notify_han
snprintf(video->phys, sizeof(video->phys),
"%s/video/input0", acpi_device_hid(video->device));
- input->name = acpi_device_name(video->device);
+ input->name = "Video Bus";
input->phys = video->phys;
input->id.bustype = BUS_HOST;
input->id.product = 0x06;
@@ -2019,7 +2015,6 @@ static int acpi_video_bus_probe(struct a
auxiliary_set_drvdata(aux_dev, video);
video->device = device;
- strscpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
strscpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
device->driver_data = video;
@@ -2041,11 +2036,10 @@ static int acpi_video_bus_probe(struct a
*/
acpi_device_fix_up_power_children(device);
- pr_info("%s [%s] (multi-head: %s rom: %s post: %s)\n",
- ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
- str_yes_no(video->flags.multihead),
- str_yes_no(video->flags.rom),
- str_yes_no(video->flags.post));
+ pr_info("Video Device [%s] (multi-head: %s rom: %s post: %s)\n",
+ acpi_device_bid(device), str_yes_no(video->flags.multihead),
+ str_yes_no(video->flags.rom), str_yes_no(video->flags.post));
+
mutex_lock(&video_list_lock);
list_add_tail(&video->entry, &video_bus_head);
mutex_unlock(&video_list_lock);
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -33,8 +33,6 @@
#define ACPI_BATTERY_CAPACITY_VALID(capacity) \
((capacity) != 0 && (capacity) != ACPI_BATTERY_VALUE_UNKNOWN)
-#define ACPI_BATTERY_DEVICE_NAME "Battery"
-
/* Battery power unit: 0 means mW, 1 means mA */
#define ACPI_BATTERY_POWER_UNIT_MA 1
@@ -1229,7 +1227,6 @@ static int acpi_battery_probe(struct pla
platform_set_drvdata(pdev, battery);
battery->device = device;
- strscpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
strscpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
result = devm_mutex_init(&pdev->dev, &battery->update_lock);
--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -558,27 +558,26 @@ static int acpi_button_probe(struct plat
goto err_free_button;
}
- name = acpi_device_name(device);
class = acpi_device_class(device);
if (!strcmp(hid, ACPI_BUTTON_HID_POWER) ||
!strcmp(hid, ACPI_BUTTON_HID_POWERF)) {
button->type = ACPI_BUTTON_TYPE_POWER;
handler = acpi_button_notify;
- strscpy(name, ACPI_BUTTON_DEVICE_NAME_POWER, MAX_ACPI_DEVICE_NAME_LEN);
+ name = ACPI_BUTTON_DEVICE_NAME_POWER;
sprintf(class, "%s/%s",
ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_POWER);
} else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEP) ||
!strcmp(hid, ACPI_BUTTON_HID_SLEEPF)) {
button->type = ACPI_BUTTON_TYPE_SLEEP;
handler = acpi_button_notify;
- strscpy(name, ACPI_BUTTON_DEVICE_NAME_SLEEP, MAX_ACPI_DEVICE_NAME_LEN);
+ name = ACPI_BUTTON_DEVICE_NAME_SLEEP;
sprintf(class, "%s/%s",
ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_SLEEP);
} else if (!strcmp(hid, ACPI_BUTTON_HID_LID)) {
button->type = ACPI_BUTTON_TYPE_LID;
handler = acpi_lid_notify;
- strscpy(name, ACPI_BUTTON_DEVICE_NAME_LID, MAX_ACPI_DEVICE_NAME_LEN);
+ name = ACPI_BUTTON_DEVICE_NAME_LID;
sprintf(class, "%s/%s",
ACPI_BUTTON_CLASS, ACPI_BUTTON_SUBCLASS_LID);
input->open = acpi_lid_input_open;
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -36,7 +36,6 @@
#include "internal.h"
#define ACPI_EC_CLASS "embedded_controller"
-#define ACPI_EC_DEVICE_NAME "Embedded Controller"
/* EC status register */
#define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */
@@ -1681,7 +1680,6 @@ static int acpi_ec_probe(struct platform
struct acpi_ec *ec;
int ret;
- strscpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
strscpy(acpi_device_class(device), ACPI_EC_CLASS);
if (boot_ec && (boot_ec->handle == device->handle ||
--- a/drivers/acpi/pci_link.c
+++ b/drivers/acpi/pci_link.c
@@ -30,7 +30,6 @@
#include "internal.h"
#define ACPI_PCI_LINK_CLASS "pci_irq_routing"
-#define ACPI_PCI_LINK_DEVICE_NAME "PCI Interrupt Link"
#define ACPI_PCI_LINK_MAX_POSSIBLE 16
static int acpi_pci_link_add(struct acpi_device *device,
@@ -725,7 +724,6 @@ static int acpi_pci_link_add(struct acpi
return -ENOMEM;
link->device = device;
- strscpy(acpi_device_name(device), ACPI_PCI_LINK_DEVICE_NAME);
strscpy(acpi_device_class(device), ACPI_PCI_LINK_CLASS);
device->driver_data = link;
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -25,7 +25,6 @@
#include "internal.h"
#define ACPI_PCI_ROOT_CLASS "pci_bridge"
-#define ACPI_PCI_ROOT_DEVICE_NAME "PCI Root Bridge"
static int acpi_pci_root_add(struct acpi_device *device,
const struct acpi_device_id *not_used);
static void acpi_pci_root_remove(struct acpi_device *device);
@@ -689,7 +688,6 @@ static int acpi_pci_root_add(struct acpi
root->device = device;
root->segment = segment & 0xFFFF;
- strscpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
strscpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
device->driver_data = root;
@@ -698,9 +696,8 @@ static int acpi_pci_root_add(struct acpi
goto end;
}
- pr_info("%s [%s] (domain %04x %pR)\n",
- acpi_device_name(device), acpi_device_bid(device),
- root->segment, &root->secondary);
+ pr_info("PCI Root Bridge [%s] (domain %04x %pR)\n",
+ acpi_device_bid(device), root->segment, &root->secondary);
root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -38,7 +38,6 @@
#include "internal.h"
#define ACPI_POWER_CLASS "power_resource"
-#define ACPI_POWER_DEVICE_NAME "Power Resource"
#define ACPI_POWER_RESOURCE_STATE_OFF 0x00
#define ACPI_POWER_RESOURCE_STATE_ON 0x01
#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
@@ -955,7 +954,6 @@ struct acpi_device *acpi_add_power_resou
mutex_init(&resource->resource_lock);
INIT_LIST_HEAD(&resource->list_node);
INIT_LIST_HEAD(&resource->dependents);
- strscpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
strscpy(acpi_device_class(device), ACPI_POWER_CLASS);
device->power.state = ACPI_STATE_UNKNOWN;
device->flags.match_driver = true;
--- a/drivers/acpi/sbs.c
+++ b/drivers/acpi/sbs.c
@@ -648,7 +648,6 @@ static int acpi_sbs_probe(struct platfor
sbs->hc = dev_get_drvdata(pdev->dev.parent);
sbs->device = device;
- strscpy(acpi_device_name(device), ACPI_SBS_DEVICE_NAME);
strscpy(acpi_device_class(device), ACPI_SBS_CLASS);
result = acpi_charger_add(sbs);
--- a/drivers/acpi/sbshc.c
+++ b/drivers/acpi/sbshc.c
@@ -19,7 +19,6 @@
#include "internal.h"
#define ACPI_SMB_HC_CLASS "smbus_host_ctl"
-#define ACPI_SMB_HC_DEVICE_NAME "ACPI SMBus HC"
struct acpi_smb_hc {
struct acpi_ec *ec;
@@ -251,7 +250,6 @@ static int acpi_smbus_hc_probe(struct pl
return -EIO;
}
- strscpy(acpi_device_name(device), ACPI_SMB_HC_DEVICE_NAME);
strscpy(acpi_device_class(device), ACPI_SMB_HC_CLASS);
hc = kzalloc_obj(struct acpi_smb_hc);
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -35,7 +35,6 @@
#include "internal.h"
#define ACPI_THERMAL_CLASS "thermal_zone"
-#define ACPI_THERMAL_DEVICE_NAME "Thermal Zone"
#define ACPI_THERMAL_NOTIFY_TEMPERATURE 0x80
#define ACPI_THERMAL_NOTIFY_THRESHOLDS 0x81
#define ACPI_THERMAL_NOTIFY_DEVICES 0x82
@@ -800,7 +799,6 @@ static int acpi_thermal_probe(struct pla
tz->device = device;
strscpy(tz->name, device->pnp.bus_id);
- strscpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
strscpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
acpi_thermal_aml_dependency_fix(tz);
@@ -879,8 +877,8 @@ static int acpi_thermal_probe(struct pla
mutex_init(&tz->thermal_check_lock);
INIT_WORK(&tz->thermal_check_work, acpi_thermal_check_fn);
- pr_info("%s [%s] (%ld C)\n", acpi_device_name(device),
- acpi_device_bid(device), deci_kelvin_to_celsius(tz->temp_dk));
+ pr_info("Thermal Zone [%s] (%ld C)\n", acpi_device_bid(device),
+ deci_kelvin_to_celsius(tz->temp_dk));
result = acpi_dev_install_notify_handler(device, ACPI_DEVICE_NOTIFY,
acpi_thermal_notify, tz);
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -15,7 +15,6 @@
#include <asm/acpi.h>
#define ACPI_PROCESSOR_CLASS "processor"
-#define ACPI_PROCESSOR_DEVICE_NAME "Processor"
#define ACPI_PROCESSOR_DEVICE_HID "ACPI0007"
#define ACPI_PROCESSOR_CONTAINER_HID "ACPI0010"