zephyr: shim: implement a default led_set_brightness

Implement a default led_set_brightness, should be good enough to replace
all existing pwm leds currently defined:

atlas, nocturne: 2 leds with independent channels
volteer, boldar, trondo: 2 leds with sidesel
terrador, todor, waddledee, wheelie: 1 led
brya, kano, liara, waddledoo: 2 leds but only amber/white
grunt:1 led with only blue/amber

BRANCH=none
BUG=b:177452529
TEST=build and run on volteer
TEST=gdb disassemble/s led_set_brightness

Signed-off-by: Fabio Baltieri <fabiobaltieri@google.com>
Change-Id: I24cb10574889ccfbc7c9fddc70ceb81d1e8b2170
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3207147
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>

4 files changed, 78 insertions, 1 deletions

diff --git a/board/volteer/led.c b/board/volteer/led.c
index 6b09d5b4a0..e4d52c889f 100644
--- a/board/volteer/led.c
+++ b/board/volteer/led.c
@@ -49,7 +49,6 @@ void led_get_brightness_range(enum ec_led_id led_id, uint8_t *brightness_range)
 	brightness_range[EC_LED_COLOR_GREEN] = 255;
 	brightness_range[EC_LED_COLOR_BLUE] = 255;
 }
-#endif
 
 int led_set_brightness(enum ec_led_id led_id, const uint8_t *brightness)
 {
@@ -79,6 +78,7 @@ int led_set_brightness(enum ec_led_id led_id, const uint8_t *brightness)
 
 	return EC_SUCCESS;
 }
+#endif
 
 /* Illuminates the LED on the side of the active charging port. If not charging,
  * illuminates both LEDs.
diff --git a/zephyr/dts/bindings/led/cros-ec,pwm-leds.yaml b/zephyr/dts/bindings/led/cros-ec,pwm-leds.yaml
index cad2e14088..b629ceac0a 100644
--- a/zephyr/dts/bindings/led/cros-ec,pwm-leds.yaml
+++ b/zephyr/dts/bindings/led/cros-ec,pwm-leds.yaml
@@ -74,3 +74,32 @@ properties:
     description: |
       A list of brigthness range value for all supported channels in order,
       Red, Green, Blue, Yellow, White, Amber (0 to 255).
+
+child-binding:
+  description: |
+    LED child binding node for mapping a PWM_LED to a EC_LED_ID.
+
+    For example
+
+    pwm_led_0@0 {
+                reg = <0>;
+                ec-led-name = "EC_LED_ID_LEFT_LED";
+    };
+    pwm_led_1@1 {
+                reg = <1>;
+                ec-led-name = "EC_LED_ID_RIGHT_LED";
+    };
+
+  properties:
+    reg:
+      type: int
+      required: true
+      description: LED ID, can be either 0 or 1 for PWM_LED0 and PWM_LED1
+      enum:
+        - 0 # PWM_LED0
+        - 1 # PWM_LED1
+
+    ec-led-name:
+      type: string
+      required: true
+      description: The EC_LED_ID value to map the LED to.
diff --git a/zephyr/projects/volteer/volteer/pwm_leds.dts b/zephyr/projects/volteer/volteer/pwm_leds.dts
index 659cdecbf2..f5c33d0d97 100644
--- a/zephyr/projects/volteer/volteer/pwm_leds.dts
+++ b/zephyr/projects/volteer/volteer/pwm_leds.dts
@@ -28,5 +28,13 @@
 		color-map-amber  = <100  20   0>;
 
 		brightness-range = <255 255 255 0 0 0>;
+
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		pwm_led_0@0 {
+			reg = <0>;
+			ec-led-name = "EC_LED_ID_POWER_LED";
+		};
 	};
 };
diff --git a/zephyr/shim/src/pwm_led.c b/zephyr/shim/src/pwm_led.c
index 4fef611a76..994c217fcf 100644
--- a/zephyr/shim/src/pwm_led.c
+++ b/zephyr/shim/src/pwm_led.c
@@ -71,4 +71,44 @@ void led_get_brightness_range(enum ec_led_id led_id, uint8_t *brightness_range)
 	       sizeof(dt_brigthness_range));
 }
 
+#define PWM_NAME_TO_ID(node_id) \
+	case DT_STRING_TOKEN(node_id, ec_led_name): \
+		pwm_id = DT_REG_ADDR(node_id); \
+		break;
+
+int led_set_brightness(enum ec_led_id led_id, const uint8_t *brightness)
+{
+	enum pwm_led_id pwm_id;
+
+	switch (led_id) {
+	DT_INST_FOREACH_CHILD(0, PWM_NAME_TO_ID)
+	default:
+		return EC_ERROR_UNKNOWN;
+	}
+
+	if (DT_INST_NODE_HAS_PROP(0, color_map_red) &&
+	    brightness[EC_LED_COLOR_RED])
+		set_pwm_led_color(pwm_id, EC_LED_COLOR_RED);
+	else if (DT_INST_NODE_HAS_PROP(0, color_map_green) &&
+		 brightness[EC_LED_COLOR_GREEN])
+		set_pwm_led_color(pwm_id, EC_LED_COLOR_GREEN);
+	else if (DT_INST_NODE_HAS_PROP(0, color_map_blue) &&
+			brightness[EC_LED_COLOR_BLUE])
+		set_pwm_led_color(pwm_id, EC_LED_COLOR_BLUE);
+	else if (DT_INST_NODE_HAS_PROP(0, color_map_yellow) &&
+			brightness[EC_LED_COLOR_YELLOW])
+		set_pwm_led_color(pwm_id, EC_LED_COLOR_YELLOW);
+	else if (DT_INST_NODE_HAS_PROP(0, color_map_white) &&
+			brightness[EC_LED_COLOR_WHITE])
+		set_pwm_led_color(pwm_id, EC_LED_COLOR_WHITE);
+	else if (DT_INST_NODE_HAS_PROP(0, color_map_amber) &&
+			brightness[EC_LED_COLOR_AMBER])
+		set_pwm_led_color(pwm_id, EC_LED_COLOR_AMBER);
+	else
+		/* Otherwise, the "color" is "off". */
+		set_pwm_led_color(pwm_id, -1);
+
+	return EC_SUCCESS;
+}
+
 #endif /* DT_HAS_COMPAT_STATUS_OKAY */