zephyr: drivers: thermistors are device tree nodes

Thermistor drivers now query the device tree for configuration.
Thermistor tests have been updated to be parameterized
on all thermistors enabled in the device tree.

BRANCH=none
BUG=b:184374937
TEST= 1) zmake testall
      2) make runhosttests

Cq-Depend: chromium:3161332
Signed-off-by: Aaron Massey <aaronmassey@chromium.org>
Change-Id: Ic5330cd5c33e79e192428ca857651de9a225856e
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3133812
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
Tested-by: Aaron Massey <aaronmassey@google.com>
Commit-Queue: Aaron Massey <aaronmassey@google.com>

7 files changed, 72 insertions, 108 deletions

diff --git a/zephyr/dts/bindings/temp/temp_sensor.yaml b/zephyr/dts/bindings/temp/cros_ec_temp_sensor.yaml
index 753cfab967..288dc2d1c8 100644
--- a/zephyr/dts/bindings/temp/temp_sensor.yaml
+++ b/zephyr/dts/bindings/temp/cros_ec_temp_sensor.yaml
@@ -2,11 +2,23 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-# Common properties for temperature sensors
-# Zero values in degrees K(-273 in degrees C)in thermal thresholds will
-# be ignored
+description: >
+  Common properties for temperature sensors
+  Zero values in degrees K(-273 in degrees C)in thermal thresholds will
+  be ignored
+
+compatible: cros-ec,temp-sensor
 
 properties:
+    adc:
+      required: true
+      type: phandle
+      description: The named adc channel
+
+    thermistor:
+      type: phandle
+      description: Underlying thermistor device if used
+
     label:
       required: true
       type: string
@@ -26,34 +38,26 @@ properties:
       - TEMP_SENSOR_PP3300_REGULATOR
 
     temp_fan_off:
-      required: false
       type: int
-      default: -273
       description:
         Temperature threshold in degrees C when no active cooling
         is needed
 
     temp_fan_max:
-      required: false
       type: int
-      default: -273
       description:
         Temperature threshold in degrees C when max active cooling
         is needed
 
     temp_host_warn:
-      required: false
       type: int
-      default: -273
       description:
         Temperature threshold in degrees C of thermal warn.
         Temperatures above the thermal warn threshold generate a
         request to the AP to throttle itself.
 
     temp_host_high:
-      required: false
       type: int
-      default: -273
       description:
         Temperature threshold in degrees C of thermal high.
         Temperatures above the thermal high threshold cause the EC to
@@ -61,30 +65,22 @@ properties:
         throttle.
 
     temp_host_halt:
-      required: false
       type: int
-      default: -273
       description:
         Temperature threshold in degrees C that forces AP to shutdown
         due to thermal reason
 
     temp_host_release_warn:
-      required: false
       type: int
-      default: -273
       description:
         Temperature release threshold in degrees C of thermal warn
 
     temp_host_release_high:
-      required: false
       type: int
-      default: -273
       description:
         Temperature release threshold in degrees C of thermal high
 
     temp_host_release_halt:
-      required: false
       type: int
-      default: -273
       description:
         Temperature release threshold in degrees C of thermal shutdown
diff --git a/zephyr/dts/bindings/temp/cros_ec_thermistor.yaml b/zephyr/dts/bindings/temp/cros_ec_thermistor.yaml
new file mode 100644
index 0000000000..d4bc32ed3c
--- /dev/null
+++ b/zephyr/dts/bindings/temp/cros_ec_thermistor.yaml
@@ -0,0 +1,57 @@
+# Copyright 2021 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# For more information:
+# https://www.electronics-tutorials.ws/io/thermistors.html
+
+description: Common properties for thermistors
+
+compatible: cros-ec,thermistor
+
+properties:
+  scaling-factor:
+    required: true
+    type: int
+    description: Scaling factor for voltage pairs
+
+  num-pairs:
+    required: true
+    type: int
+    description: Number of sample data points for linear interpolation
+
+  steinhart-reference-mv:
+    required: true
+    type: int
+    description: >
+      Used only for testing.
+      Is the reference voltage for temperature 25C.
+
+  steinhart-reference-res:
+    required: true
+    type: int
+    description: >
+      Used only for testing.
+      Is the reference resistance for temperature 25C.
+
+child-binding:
+  description: >
+    Data samples derived from Steinhart-Hart
+    equation in a resistor divider circuit.
+    Used in linear interpolation.
+
+  properties:
+    milivolt:
+      type: int
+      required: true
+      description: Voltage reading for a given temperature sample
+
+    temp:
+      type: int
+      required: true
+      description: Temperature (Celcius) in a sample
+
+    sample-index:
+      type: int
+      required: true
+      description: The index of a datum to maintain sample order to interpolate.
diff --git a/zephyr/dts/bindings/temp/temp-3v0-22k6-47k-4050b.yaml b/zephyr/dts/bindings/temp/temp-3v0-22k6-47k-4050b.yaml
deleted file mode 100644
index 09390a3656..0000000000
--- a/zephyr/dts/bindings/temp/temp-3v0-22k6-47k-4050b.yaml
+++ /dev/null
@@ -1,15 +0,0 @@
-# Copyright 2021 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-description: Thermistor 3v0-22k6-47k-4050b
-
-compatible: "temp-3v0-22k6-47k-4050b"
-
-include: [temp_sensor.yaml, thermistor.yaml]
-
-properties:
-  get-temp-func:
-    enum:
-    - get_temp_3v0_22k6_47k_4050b
-    default: get_temp_3v0_22k6_47k_4050b
diff --git a/zephyr/dts/bindings/temp/temp-3v3-13k7-47k-4050b.yaml b/zephyr/dts/bindings/temp/temp-3v3-13k7-47k-4050b.yaml
deleted file mode 100644
index 76b6dfaa30..0000000000
--- a/zephyr/dts/bindings/temp/temp-3v3-13k7-47k-4050b.yaml
+++ /dev/null
@@ -1,15 +0,0 @@
-# Copyright 2021 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-description: Thermistor 3v3-13k7-47k-4050b
-
-compatible: "temp-3v3-13k7-47k-4050b"
-
-include: [temp_sensor.yaml, thermistor.yaml]
-
-properties:
-  get-temp-func:
-    enum:
-    - get_temp_3v3_13k7_47k_4050b
-    default: get_temp_3v3_13k7_47k_4050b
diff --git a/zephyr/dts/bindings/temp/temp-3v3-30k9-47k-4050b.yaml b/zephyr/dts/bindings/temp/temp-3v3-30k9-47k-4050b.yaml
deleted file mode 100644
index 4d45a0eb51..0000000000
--- a/zephyr/dts/bindings/temp/temp-3v3-30k9-47k-4050b.yaml
+++ /dev/null
@@ -1,15 +0,0 @@
-# Copyright 2021 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-description: Thermistor 3v3-30k9-47k-4050b
-
-compatible: "temp-3v3-30k9-47k-4050b"
-
-include: [temp_sensor.yaml, thermistor.yaml]
-
-properties:
-  get-temp-func:
-    enum:
-    - get_temp_3v3_30k9_47k_4050b
-    default: get_temp_3v3_30k9_47k_4050b
diff --git a/zephyr/dts/bindings/temp/temp-3v3-51k1-47k-4050b.yaml b/zephyr/dts/bindings/temp/temp-3v3-51k1-47k-4050b.yaml
deleted file mode 100644
index 0b8343f909..0000000000
--- a/zephyr/dts/bindings/temp/temp-3v3-51k1-47k-4050b.yaml
+++ /dev/null
@@ -1,15 +0,0 @@
-# Copyright 2021 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-description: Thermistor 3v3-51k1-47k-4050b
-
-compatible: "temp-3v3-51k1-47k-4050b"
-
-include: [temp_sensor.yaml, thermistor.yaml]
-
-properties:
-  get-temp-func:
-    enum:
-    - get_temp_3v3_51k1_47k_4050b
-    default: get_temp_3v3_51k1_47k_4050b
diff --git a/zephyr/dts/bindings/temp/thermistor.yaml b/zephyr/dts/bindings/temp/thermistor.yaml
deleted file mode 100644
index 66a07de945..0000000000
--- a/zephyr/dts/bindings/temp/thermistor.yaml
+++ /dev/null
@@ -1,29 +0,0 @@
-# Copyright 2021 The Chromium OS Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# Common properties for thermistors
-
-properties:
-  adc:
-    required: true
-    type: phandle
-    description: named-adc child node connected to the thermistor
-
-  get-temp-func:
-    type: string
-    required: false
-    description: >
-      Name of the board-provided function which reads the temperature. If you
-      have different values and need to add a new function, you can add that
-      here.
-
-      The name is get_temp_<v>_<rs>_<rn>_<b>:
-
-      v: voltage of resistor-divider circuit
-      rs: value of the resistor that is in series with the thermistor
-      rn: nominal resistance of thermistor at 25C
-      b: B value for temperature range 25C to 100C
-
-      See https://www.electronics-tutorials.ws/io/thermistors.html for more
-      information.