Spektrum SRXL2 ESC: enable the driver and fix protocol decoding

.github/scripts/check-pg-versions.sh

@@ -187,7 +187,9 @@ while IFS= read -r file; do
     fi
 
     # Determine companion file (.c <-> .h)
-    local companion=""
+    # NOTE: this loop runs in the main script body, not inside a function, so
+    # `local` is invalid here and aborts the script under `set -e`.
+    companion=""
     if [[ "$file" == *.c ]]; then
         companion="${file%.c}.h"
     elif [[ "$file" == *.h ]]; then

docs/Settings.md

@@ -3273,6 +3273,7 @@ Protocol that is used to send motor updates to ESCs. Possible values - STANDARD,
 | DSHOT150 |  |
 | DSHOT300 |  |
 | DSHOT600 |  |
+| SRXL2 |  |
 
 ---
 

src/main/CMakeLists.txt

@@ -267,6 +267,8 @@ main_sources(COMMON_SRC
     drivers/rcc.h
     drivers/serial.c
     drivers/serial.h
+    drivers/srxl2_esc.c
+    drivers/srxl2_esc.h
     drivers/sound_beeper.c
     drivers/sound_beeper.h
     drivers/stack_check.c

src/main/common/log.c

@@ -205,8 +205,10 @@ void _logBufferHex(logTopic_e topic, unsigned level, const void *buffer, size_t
 {
     // Print lines of up to maxBytes bytes. We need 5 characters per byte
     // 0xAB[space|\n]
-    const size_t charsPerByte = 5;
-    const size_t maxBytes = 8;
+    // Use enum constants (not const size_t locals) so the buffer size is a true
+    // integer constant expression. Newer Apple clang otherwise folds the const
+    // locals and reports the array as a VLA (-Werror=gnu-folding-constant).
+    enum { charsPerByte = 5, maxBytes = 8 };
     char buf[LOG_PREFIX_FORMATTED_SIZE + charsPerByte * maxBytes + 1]; // +1 for the null terminator
     size_t bufPos = LOG_PREFIX_FORMATTED_SIZE;
     const uint8_t *inputPtr = buffer;

src/main/drivers/pwm_mapping.c

@@ -70,6 +70,7 @@ static const motorProtocolProperties_t motorProtocolProperties[] = {
     [PWM_TYPE_DSHOT150]     = { .usesHwTimer = true,    .isDSHOT = true },
     [PWM_TYPE_DSHOT300]     = { .usesHwTimer = true,    .isDSHOT = true },
     [PWM_TYPE_DSHOT600]     = { .usesHwTimer = true,    .isDSHOT = true },
+    [PWM_TYPE_SRXL2]        = { .usesHwTimer = false,   .isDSHOT = false },
 };
 
 pwmInitError_e getPwmInitError(void)

src/main/drivers/pwm_mapping.h

@@ -47,6 +47,7 @@ typedef enum {
     PWM_TYPE_DSHOT150,
     PWM_TYPE_DSHOT300,
     PWM_TYPE_DSHOT600,
+    PWM_TYPE_SRXL2,
 } motorPwmProtocolTypes_e;
 
 typedef enum {

src/main/drivers/pwm_output.c

@@ -34,6 +34,7 @@
 #include "drivers/timer.h"
 #include "drivers/pwm_mapping.h"
 #include "drivers/pwm_output.h"
+#include "drivers/srxl2_esc.h"
 #include "io/servo_sbus.h"
 #include "sensors/esc_sensor.h"
 
@@ -211,6 +212,11 @@ static void pwmWriteStandard(uint8_t index, uint16_t value)
     }
 }
 
+static void pwmWriteSrxl2(uint8_t index, uint16_t value)
+{
+    srxl2EscWriteMotor(index, value);
+}
+
 void pwmWriteMotor(uint8_t index, uint16_t value)
 {
     if (motorWritePtr && index < MAX_MOTORS && pwmMotorsEnabled) {
@@ -518,7 +524,27 @@ static bool executeDShotCommands(void){
 }
 #endif
 
+#else // digital motor protocol
+
+// This stub is needed to avoid ESC_SENSOR dependency on DSHOT
+void pwmRequestMotorTelemetry(int motorIndex)
+{
+    UNUSED(motorIndex);
+}
+
+#endif
+
+// pwmCompleteMotorUpdate must also exist for SRXL2-only targets (no DSHOT),
+// where it just drives the SRXL2 transmit. The digital/DSHOT body below is
+// kept behind USE_DSHOT so it is omitted on those targets.
+#if defined(USE_DSHOT) || defined(USE_SRXL2_ESC)
 void pwmCompleteMotorUpdate(void) {
+    if (initMotorProtocol == PWM_TYPE_SRXL2) {
+        srxl2EscUpdate(micros());
+        return;
+    }
+
+#ifdef USE_DSHOT
     // This only makes sense for digital motor protocols
     if (!isMotorProtocolDigital()) {
         return;
@@ -574,16 +600,8 @@ void pwmCompleteMotorUpdate(void) {
 #endif
     }
 #endif
+#endif
 }
-
-#else // digital motor protocol
-
-// This stub is needed to avoid ESC_SENSOR dependency on DSHOT
-void pwmRequestMotorTelemetry(int motorIndex)
-{
-    UNUSED(motorIndex);
-}
-
 #endif
 
 void pwmMotorPreconfigure(void)
@@ -608,6 +626,18 @@ void pwmMotorPreconfigure(void)
             motorWritePtr = pwmWriteStandard;
             break;
 
+        case PWM_TYPE_SRXL2:
+            // SRXL2 paces its own transmissions inside srxl2EscUpdate() and
+            // pwmCompleteMotorUpdate() returns early for it, so the digital update
+            // interval is unused here. Avoid calling motorConfigDigitalUpdateInterval()
+            // which is only defined when USE_DSHOT is enabled.
+            if (srxl2EscInit()) {
+                motorWritePtr = pwmWriteSrxl2;
+            } else {
+                motorWritePtr = pwmWriteNull;
+            }
+            break;
+
 #ifdef USE_DSHOT
         case PWM_TYPE_DSHOT600:
         case PWM_TYPE_DSHOT300:
@@ -642,6 +672,9 @@ uint32_t getEscUpdateFrequency(void) {
         case PWM_TYPE_DSHOT600:
             return 16000;
 
+        case PWM_TYPE_SRXL2:
+            return SRXL2_ESC_UPDATE_HZ;
+
         case PWM_TYPE_ONESHOT125:
         default:
             return 1000;
@@ -676,6 +709,10 @@ bool pwmMotorConfig(const timerHardware_t *timerHardware, uint8_t motorIndex, bo
         motors[motorIndex].pwmPort = motorConfigPwm(timerHardware, 1e-3f, 1e-3f, getEscUpdateFrequency(), enableOutput);
         break;
 
+    case PWM_TYPE_SRXL2:
+        motors[motorIndex].pwmPort = NULL;
+        break;
+
     default:
         motors[motorIndex].pwmPort = NULL;
         break;