ACPI: processor: Split out thermal initialization from ACPI PSS

Commit 239708a3af44 ("ACPI: Split out ACPI PSS from ACPI Processor
driver"), moves processor thermal registration to acpi_pss_perf_init(),
which doesn't get executed if ACPI_CPU_FREQ_PSS is not enabled.

As ARM64 supports P-states using CPPC, it should be possible to also
support processor passive cooling even if PSS is not enabled. Split
out the processor thermal cooling register from ACPI PSS to support
this, and move it into a separate function in processor_thermal.c.

Signed-off-by: Riwen Lu <luriwen@kylinos.cn>
Reviewed-by: Punit Agrawal <punit.agrawal@bytedance.com>
[ rjw: Subject edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 54 insertions, 0 deletions

diff --git a/drivers/acpi/processor_thermal.c b/drivers/acpi/processor_thermal.c
index d8b2dfcd59b5..db6ac540e924 100644
--- a/drivers/acpi/processor_thermal.c
+++ b/drivers/acpi/processor_thermal.c
@@ -266,3 +266,57 @@ const struct thermal_cooling_device_ops processor_cooling_ops = {
 	.get_cur_state = processor_get_cur_state,
 	.set_cur_state = processor_set_cur_state,
 };
+
+int acpi_processor_thermal_init(struct acpi_processor *pr,
+				struct acpi_device *device)
+{
+	int result = 0;
+
+	pr->cdev = thermal_cooling_device_register("Processor", device,
+						   &processor_cooling_ops);
+	if (IS_ERR(pr->cdev)) {
+		result = PTR_ERR(pr->cdev);
+		return result;
+	}
+
+	dev_dbg(&device->dev, "registered as cooling_device%d\n",
+		pr->cdev->id);
+
+	result = sysfs_create_link(&device->dev.kobj,
+				   &pr->cdev->device.kobj,
+				   "thermal_cooling");
+	if (result) {
+		dev_err(&device->dev,
+			"Failed to create sysfs link 'thermal_cooling'\n");
+		goto err_thermal_unregister;
+	}
+
+	result = sysfs_create_link(&pr->cdev->device.kobj,
+				   &device->dev.kobj,
+				   "device");
+	if (result) {
+		dev_err(&pr->cdev->device,
+			"Failed to create sysfs link 'device'\n");
+		goto err_remove_sysfs_thermal;
+	}
+
+	return 0;
+
+err_remove_sysfs_thermal:
+	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
+err_thermal_unregister:
+	thermal_cooling_device_unregister(pr->cdev);
+
+	return result;
+}
+
+void acpi_processor_thermal_exit(struct acpi_processor *pr,
+				 struct acpi_device *device)
+{
+	if (pr->cdev) {
+		sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
+		sysfs_remove_link(&pr->cdev->device.kobj, "device");
+		thermal_cooling_device_unregister(pr->cdev);
+		pr->cdev = NULL;
+	}
+}