thermal/drivers/tegra: Add driver for Tegra30 thermal sensor

All NVIDIA Tegra30 SoCs have a two-channel on-chip sensor unit which
monitors temperature and voltage of the SoC. Sensors control CPU frequency
throttling, which is activated by hardware once preprogrammed temperature
level is breached, they also send signal to Power Management controller to
perform emergency shutdown on a critical overheat of the SoC die. Add
driver for the Tegra30 TSENSOR module, exposing it as a thermal sensor.

Tested-by: Andreas Westman Dorcsak <hedmoo@yahoo.com> # Asus TF700T
Tested-by: Maxim Schwalm <maxim.schwalm@gmail.com> # Asus TF700T
Tested-by: Svyatoslav Ryhel <clamor95@gmail.com> # Asus TF201T
Tested-by: Ihor Didenko <tailormoon@rambler.ru> # Asus TF300T
Tested-by: Ion Agorria <ion@agorria.com> # Asus TF201T
Tested-by: Matt Merhar <mattmerhar@protonmail.com> # Ouya
Tested-by: Peter Geis <pgwipeout@gmail.com> # Ouya
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210616190417.32214-4-digetx@gmail.com

drivers/thermal/tegra/Kconfig

@@ -18,4 +18,11 @@ config TEGRA_BPMP_THERMAL
 	  Enable this option for support for sensing system temperature of NVIDIA
 	  Tegra systems-on-chip with the BPMP coprocessor (Tegra186).
 
+config TEGRA30_TSENSOR
+	tristate "Tegra30 Thermal Sensor"
+	depends on ARCH_TEGRA_3x_SOC || COMPILE_TEST
+	help
+	  Enable this option to support thermal management of NVIDIA Tegra30
+	  system-on-chip.
+
 endmenu

drivers/thermal/tegra/Makefile

 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_TEGRA_SOCTHERM)		+= tegra-soctherm.o
 obj-$(CONFIG_TEGRA_BPMP_THERMAL)	+= tegra-bpmp-thermal.o
+obj-$(CONFIG_TEGRA30_TSENSOR)		+= tegra30-tsensor.o
 
 tegra-soctherm-y				:= soctherm.o soctherm-fuse.o
 tegra-soctherm-$(CONFIG_ARCH_TEGRA_124_SOC)	+= tegra124-soctherm.o