acpi_thermal: implement B_GET_DEVICE_NAME

Get the name from the _STR method of the ACPI object.
Convert from UTF16 as needed.

In cases where the ACPI implementation provides multiple zones, this
allows to differenciate them.

Change-Id: If349207dcfd22cc9c3baf50b8f8d63d56dc62f21
Reviewed-on: https://review.haiku-os.org/c/haiku/+/9739
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: waddlesplash <[email protected]>

src/add-ons/kernel/drivers/power/acpi_thermal/Jamfile

@@ -1,5 +1,7 @@
 SubDir HAIKU_TOP src add-ons kernel drivers power acpi_thermal ;
 
+UsePrivateKernelHeaders ;
+
 KernelAddon acpi_thermal :
 	acpi_thermal.c
 	;

src/add-ons/kernel/drivers/power/acpi_thermal/acpi_thermal.c

@@ -17,6 +17,9 @@
 #include <stdlib.h>
 
 #include <ACPI.h>
+
+#include <util/convertutf.h>
+
 #include "acpi_thermal.h"
 
 #define ACPI_THERMAL_MODULE_NAME "drivers/power/acpi_thermal/driver_v1"
@@ -156,18 +159,53 @@ status_t
 acpi_thermal_control(void* _cookie, uint32 op, void* arg, size_t len)
 {
 	acpi_thermal_device_info* device = (acpi_thermal_device_info*)_cookie;
-	status_t err = B_ERROR;
+	status_t err = B_DEV_INVALID_IOCTL;
 
-	acpi_thermal_type* att = NULL;
+	switch (op) {
+		case B_GET_DEVICE_NAME: {
+			acpi_data buffer;
 
+			buffer.pointer = NULL;
+			buffer.length = ACPI_ALLOCATE_BUFFER;
+
+			err = device->acpi->evaluate_method (device->acpi_cookie, "_STR",
+				NULL, &buffer);
+
+			if (err != B_OK) {
+				dprintf("acpi_thermal: could not get zone name: %s\n", strerror(err));
+				free(buffer.pointer);
+				break;
+			}
+
+			acpi_object_type* object = (acpi_object_type*)buffer.pointer;
+			if (object->object_type == ACPI_TYPE_STRING) {
+				err = user_strlcpy((char*)arg, object->string.string, min(object->string.len, len));
+				free(buffer.pointer);
+			} else if (object->object_type == ACPI_TYPE_BUFFER) {
+				char utf8[256];
+				ssize_t bytes = utf16le_to_utf8(object->buffer.buffer, object->buffer.length / 2,
+					utf8, sizeof(utf8));
+				free(buffer.pointer);
+				if (bytes < 0) {
+					err = bytes;
+					break;
+				}
+
+				err = user_strlcpy((char*)arg, utf8, min((size_t)bytes, len));
+			}
+
+			if (err > 0)
+				err = B_OK;
+			break;
+		}
+		case drvOpGetThermalType: {
 			acpi_object_type object;
+			acpi_thermal_type* att = NULL;
 
 			acpi_data buffer;
 			buffer.pointer = &object;
 			buffer.length = sizeof(object);
 
-	switch (op) {
-		case drvOpGetThermalType: {
 			att = (acpi_thermal_type*)arg;
 
 			// Read basic temperature thresholds.