Change in coreboot[master]: ec/google/chromeec: Implement support for DRIVERS_ACPI_THERMAL_ZONE

[Raul Rangel (Code Review)]

Attention is currently required from: Tim Wawrzynczak.
Raul Rangel has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/54133 )

Change subject: ec/google/chromeec: Implement support for DRIVERS_ACPI_THERMAL_ZONE
......................................................................

ec/google/chromeec: Implement support for DRIVERS_ACPI_THERMAL_ZONE

This generates the required method to access temperature data from the
ChromeEC.

BUG=b:186166365
TEST=Boot guybrush to the OS

Signed-off-by: Raul E Rangel 
Change-Id: I418b6691a7d00a4c2d89c9c1fe8f9416602be0f1
---
M src/ec/google/chromeec/Makefile.inc
A src/ec/google/chromeec/thermal_zone.c
2 files changed, 20 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/33/54133/1

diff --git a/src/ec/google/chromeec/Makefile.inc b/src/ec/google/chromeec/Makefile.inc
index a37d673..a647b09 100644
--- a/src/ec/google/chromeec/Makefile.inc
+++ b/src/ec/google/chromeec/Makefile.inc
@@ -43,6 +43,7 @@
 ramstage-$(CONFIG_EC_GOOGLE_CHROMEEC_SWITCHES) += switches.c

ramstage-$(CONFIG_DRIVERS_INTEL_DPTF) += ec_dptf_helpers.c
+ramstage-$(CONFIG_DRIVERS_ACPI_THERMAL_ZONE) += thermal_zone.c

CHROMEEC_SOURCE ?= $(top)/3rdparty/chromeec

diff --git a/src/ec/google/chromeec/thermal_zone.c b/src/ec/google/chromeec/thermal_zone.c
new file mode 100644
index 0000000..6031851
--- /dev/null
+++ b/src/ec/google/chromeec/thermal_zone.c
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <acpi/acpigen.h>
+#include "drivers/acpi/thermal_zone/chip.h"
+
+enum cb_err acpigen_write_thermal_zone_get_temperature(
+	const struct drivers_acpi_thermal_zone_config *config)
+{
+	acpigen_write_method_serialized("_TMP", 0);
+
+	acpigen_emit_byte(RETURN_OP);
+	/* TODO: Can we search for the CrosEC device? */
+	acpigen_emit_namestring("\_SB.PCI0.LPCB.EC0.TSRD");
+	acpigen_write_integer(config->temperature_sensor_id);
+
+	acpigen_write_method_end();
+
+	return CB_SUCCESS;
+}