diff --git a/Documentation/admin-guide/acpi/fan_performance_states.rst b/Documentation/admin-guide/acpi/fan_performance_states.rst
new file mode 100644
index 0000000000000000000000000000000000000000..21d233ca50d8b1009cb21bd033088af60d297c39
--- /dev/null
+++ b/Documentation/admin-guide/acpi/fan_performance_states.rst
@@ -0,0 +1,62 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===========================
+ACPI Fan Performance States
+===========================
+
+When the optional _FPS object is present under an ACPI device representing a
+fan (for example, PNP0C0B or INT3404), the ACPI fan driver creates additional
+"state*" attributes in the sysfs directory of the ACPI device in question.
+These attributes list properties of fan performance states.
+
+For more information on _FPS refer to the ACPI specification at:
+
+http://uefi.org/specifications
+
+For instance, the contents of the INT3404 ACPI device sysfs directory
+may look as follows::
+
+ $ ls -l /sys/bus/acpi/devices/INT3404:00/
+ total 0
+...
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state0
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state1
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state10
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state11
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state2
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state3
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state4
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state5
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state6
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state7
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state8
+ -r--r--r-- 1 root root 4096 Dec 13 20:38 state9
+ -r--r--r-- 1 root root 4096 Dec 13 01:00 status
+ ...
+
+where each of the "state*" files represents one performance state of the fan
+and contains a colon-separated list of 5 integer numbers (fields) with the
+following interpretation::
+
+control_percent:trip_point_index:speed_rpm:noise_level_mdb:power_mw
+
+* ``control_percent``: The percent value to be used to set the fan speed to a
+ specific level using the _FSL object (0-100).
+
+* ``trip_point_index``: The active cooling trip point number that corresponds
+ to this performance state (0-9).
+
+* ``speed_rpm``: Speed of the fan in rotations per minute.
+
+* ``noise_level_mdb``: Audible noise emitted by the fan in this state in
+ millidecibels.
+
+* ``power_mw``: Power draw of the fan in this state in milliwatts.
+
+For example::
+
+ $cat /sys/bus/acpi/devices/INT3404:00/state1
+ 25:0:3200:12500:1250
+
+When a given field is not populated or its value provided by the platform
+firmware is invalid, the "not-defined" string is shown instead of the value.
diff --git a/Documentation/admin-guide/acpi/index.rst b/Documentation/admin-guide/acpi/index.rst
index 4d13eeea1ecac3ca70d8a9214237e0dd2a05d331..71277689ad97f452fb91ff8738601f6e163d1d65 100644
--- a/Documentation/admin-guide/acpi/index.rst
+++ b/Documentation/admin-guide/acpi/index.rst
@@ -12,3 +12,4 @@ the Linux ACPI support.
dsdt-override
ssdt-overlays
cppc_sysfs
+ fan_performance_states
diff --git a/drivers/acpi/fan.c b/drivers/acpi/fan.c
index 816b0803f7fb778c9165a34d2009284f6114ddb1..86d2417953b599efe0775201bd868788d09ed38c 100644
--- a/drivers/acpi/fan.c
+++ b/drivers/acpi/fan.c
@@ -44,12 +44,16 @@ static const struct dev_pm_ops acpi_fan_pm = {
#define FAN_PM_OPS_PTR NULL
#endif
+#define ACPI_FPS_NAME_LEN 20
+
struct acpi_fan_fps {
u64 control;
u64 trip_point;
u64 speed;
u64 noise_level;
u64 power;
+ char name[ACPI_FPS_NAME_LEN];
+ struct device_attribute dev_attr;
};
struct acpi_fan_fif {
@@ -265,6 +269,39 @@ static int acpi_fan_speed_cmp(const void *a, const void *b)
return fps1->speed - fps2->speed;
}
+static ssize_t show_state(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct acpi_fan_fps *fps = container_of(attr, struct acpi_fan_fps, dev_attr);
+ int count;
+
+ if (fps->control == 0xFFFFFFFF || fps->control > 100)
+ count = snprintf(buf, PAGE_SIZE, "not-defined:");
+ else
+ count = snprintf(buf, PAGE_SIZE, "%lld:", fps->control);
+
+ if (fps->trip_point == 0xFFFFFFFF || fps->trip_point > 9)
+ count += snprintf(&buf[count], PAGE_SIZE, "not-defined:");
+ else
+ count += snprintf(&buf[count], PAGE_SIZE, "%lld:", fps->trip_point);
+
+ if (fps->speed == 0xFFFFFFFF)
+ count += snprintf(&buf[count], PAGE_SIZE, "not-defined:");
+ else
+ count += snprintf(&buf[count], PAGE_SIZE, "%lld:", fps->speed);
+
+ if (fps->noise_level == 0xFFFFFFFF)
+ count += snprintf(&buf[count], PAGE_SIZE, "not-defined:");
+ else
+ count += snprintf(&buf[count], PAGE_SIZE, "%lld:", fps->noise_level * 100);
+
+ if (fps->power == 0xFFFFFFFF)
+ count += snprintf(&buf[count], PAGE_SIZE, "not-defined\n");
+ else
+ count += snprintf(&buf[count], PAGE_SIZE, "%lld\n", fps->power);
+
+ return count;
+}
+
static int acpi_fan_get_fps(struct acpi_device *device)
{
struct acpi_fan *fan = acpi_driver_data(device);
@@ -295,12 +332,13 @@ static int acpi_fan_get_fps(struct acpi_device *device)
}
for (i = 0; i < fan->fps_count; i++) {
struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
- struct acpi_buffer fps = { sizeof(fan->fps[i]), &fan->fps[i] };
+ struct acpi_buffer fps = { offsetof(struct acpi_fan_fps, name),
+ &fan->fps[i] };
status = acpi_extract_package(&obj->package.elements[i + 1],
&format, &fps);
if (ACPI_FAILURE(status)) {
dev_err(&device->dev, "Invalid _FPS element\n");
- break;
+ goto err;
}
}
@@ -308,6 +346,24 @@ static int acpi_fan_get_fps(struct acpi_device *device)
sort(fan->fps, fan->fps_count, sizeof(*fan->fps),
acpi_fan_speed_cmp, NULL);
+ for (i = 0; i < fan->fps_count; ++i) {
+ struct acpi_fan_fps *fps = &fan->fps[i];
+
+ snprintf(fps->name, ACPI_FPS_NAME_LEN, "state%d", i);
+ fps->dev_attr.show = show_state;
+ fps->dev_attr.store = NULL;
+ fps->dev_attr.attr.name = fps->name;
+ fps->dev_attr.attr.mode = 0444;
+ status = sysfs_create_file(&device->dev.kobj, &fps->dev_attr.attr);
+ if (status) {
+ int j;
+
+ for (j = 0; j < i; ++j)
+ sysfs_remove_file(&device->dev.kobj, &fan->fps[j].dev_attr.attr);
+ break;
+ }
+ }
+
err:
kfree(obj);
return status;
@@ -330,14 +386,20 @@ static int acpi_fan_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, fan);
if (acpi_fan_is_acpi4(device)) {
- if (acpi_fan_get_fif(device) || acpi_fan_get_fps(device))
- goto end;
+ result = acpi_fan_get_fif(device);
+ if (result)
+ return result;
+
+ result = acpi_fan_get_fps(device);
+ if (result)
+ return result;
+
fan->acpi4 = true;
} else {
result = acpi_device_update_power(device, NULL);
if (result) {
dev_err(&device->dev, "Failed to set initial power state\n");
- goto end;
+ goto err_end;
}
}
@@ -350,7 +412,7 @@ static int acpi_fan_probe(struct platform_device *pdev)
&fan_cooling_ops);
if (IS_ERR(cdev)) {
result = PTR_ERR(cdev);
- goto end;
+ goto err_end;
}
dev_dbg(&pdev->dev, "registered as cooling_device%d\n", cdev->id);
@@ -365,10 +427,21 @@ static int acpi_fan_probe(struct platform_device *pdev)
result = sysfs_create_link(&cdev->device.kobj,
&pdev->dev.kobj,
"device");
- if (result)
+ if (result) {
dev_err(&pdev->dev, "Failed to create sysfs link 'device'\n");
+ goto err_end;
+ }
+
+ return 0;
+
+err_end:
+ if (fan->acpi4) {
+ int i;
+
+ for (i = 0; i < fan->fps_count; ++i)
+ sysfs_remove_file(&device->dev.kobj, &fan->fps[i].dev_attr.attr);
+ }
-end:
return result;
}
@@ -376,6 +449,13 @@ static int acpi_fan_remove(struct platform_device *pdev)
{
struct acpi_fan *fan = platform_get_drvdata(pdev);
+ if (fan->acpi4) {
+ struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
+ int i;
+
+ for (i = 0; i < fan->fps_count; ++i)
+ sysfs_remove_file(&device->dev.kobj, &fan->fps[i].dev_attr.attr);
+ }
sysfs_remove_link(&pdev->dev.kobj, "thermal_cooling");
sysfs_remove_link(&fan->cdev->device.kobj, "device");
thermal_cooling_device_unregister(fan->cdev);