From 6307fd765a8d7d0db2f5b781eb4b8ac1ab072303 Mon Sep 17 00:00:00 2001
From: Laurens Valk <laurens@pybricks.com>
Date: Sat, 12 Dec 2020 14:14:07 +0100
Subject: [PATCH] pbio/iodev: add power requirement capability flag

---
 lib/lego/lego_uart.h          |  3 +++
 lib/pbio/include/pbio/iodev.h | 14 +++++++++++++-
 lib/pbio/src/uartdev.c        |  3 +++
 3 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/lib/lego/lego_uart.h b/lib/lego/lego_uart.h
index f3f3c4130..fe37b021c 100644
--- a/lib/lego/lego_uart.h
+++ b/lib/lego/lego_uart.h
@@ -541,6 +541,9 @@ typedef enum {
 
     /** This mode is a motor mode. */
     LUMP_MODE_FLAGS0_MOTOR = 1 << 5,
+
+    /** This sensor mode requires battery voltage, not just logic voltage. */
+    LUMP_MODE_FLAGS0_REQUIRES_POWER = 1 << 6,
 } lump_mode_flags0_t;
 
 /**
diff --git a/lib/pbio/include/pbio/iodev.h b/lib/pbio/include/pbio/iodev.h
index d93c9d68c..6a35bb35d 100644
--- a/lib/pbio/include/pbio/iodev.h
+++ b/lib/pbio/include/pbio/iodev.h
@@ -204,6 +204,10 @@ typedef enum {
      * Indicates that the motor provides absolute position feedback.
      */
     PBIO_IODEV_CAPABILITY_FLAG_HAS_MOTOR_ABS_POS = 1 << 3,
+    /**
+     * Indicates that a sensor requires permanent battery voltage, not just logic voltage.
+     */
+    PBIO_IODEV_CAPABILITY_FLAG_REQUIRES_POWER = 1 << 4,
 } pbio_iodev_capability_flags_t;
 
 /**
@@ -218,7 +222,15 @@ typedef enum {
  *
  * @param [in] d    Pointer to pbio_iodev_t.
  */
-#define PBIO_IODEV_IS_FEEDBACK_MOTOR(d) ((d)->capability_flags > PBIO_IODEV_CAPABILITY_FLAG_IS_MOTOR)
+#define PBIO_IODEV_IS_FEEDBACK_MOTOR(d) ((d)->capability_flags & PBIO_IODEV_CAPABILITY_FLAG_HAS_MOTOR_REL_POS)
+
+/**
+ * Macro for testing if I/O device requires battery power.
+ *
+ * @param [in] d    Pointer to pbio_iodev_t.
+ */
+#define PBIO_IODEV_REQUIRES_POWER(d) ((d)->capability_flags & PBIO_IODEV_CAPABILITY_FLAG_REQUIRES_POWER)
+
 
 /**
  * Mapping flags that describe the input and output values of an I/O device.
diff --git a/lib/pbio/src/uartdev.c b/lib/pbio/src/uartdev.c
index c57c6f7c5..b820a8ea2 100644
--- a/lib/pbio/src/uartdev.c
+++ b/lib/pbio/src/uartdev.c
@@ -494,6 +494,9 @@ static void pbio_uartdev_parse_msg(uartdev_port_data_t *data) {
                     if (flags->flags0 & LUMP_MODE_FLAGS0_MOTOR_ABS_POS) {
                         data->iodev.capability_flags |= PBIO_IODEV_CAPABILITY_FLAG_HAS_MOTOR_ABS_POS;
                     }
+                    if (flags->flags0 & LUMP_MODE_FLAGS0_REQUIRES_POWER) {
+                        data->iodev.capability_flags |= PBIO_IODEV_CAPABILITY_FLAG_REQUIRES_POWER;
+                    }
 
                     debug_pr("new_mode: %d\n", data->new_mode);
                     debug_pr("name: %s\n", data->info->mode_info[mode].name);