Merge pull request #20833 from chrysn-pull-requests/leds-provided-on-…

…demand

drivers/led: Allow LEDn_ON to be disabled by other modules

boards/common/particle-mesh/include/board.h

@@ -95,6 +95,18 @@ extern "C" {
 #define LED2_MASK           (1 << 15)
 #define LED_MASK            (LED0_MASK | LED1_MASK | LED2_MASK)
 
+/* The typical SAUL setup for this board uses PWM to make the LEDs (really a
+ * single RGB LED) into a PWM controlled RGB LED entry. As a consequence of the
+ * PWM configuration, toggling the GPIO has no effect any more, and thus we do
+ * not define the macros so that no LEDs get picked up for LEDn_IS_PROVIDED.
+ * (The LEDn_ON etc macros will still be present and no-op as usual, but those
+ * explicitly checking for IS_PROVIDED will get an accurate picture).
+ *
+ * Both conditions are typically true when saul_default is on, but strictly, it
+ * is those two that in combination make LEDs effectively unavailable to users.
+ * */
+#if !(IS_USED(MODULE_AUTO_INIT_SAUL) && IS_USED(MODULE_SAUL_PWM))
+
 #define LED0_ON             (LED_PORT->OUTCLR = LED0_MASK)
 #define LED0_OFF            (LED_PORT->OUTSET = LED0_MASK)
 #define LED0_TOGGLE         (LED_PORT->OUT   ^= LED0_MASK)
@@ -106,6 +118,9 @@ extern "C" {
 #define LED2_ON             (LED_PORT->OUTCLR = LED2_MASK)
 #define LED2_OFF            (LED_PORT->OUTSET = LED2_MASK)
 #define LED2_TOGGLE         (LED_PORT->OUT   ^= LED2_MASK)
+
+#endif /* !(IS_USED(MODULE_AUTO_INIT_SAUL) && IS_USED(MODULE_SAUL_PWM)) */
+
 /** @} */
 
 /**

drivers/periph_common/init_leds.c

@@ -17,7 +17,7 @@
  * @}
  */
 
-#include "board.h"
+#include "led.h"
 #include "periph/gpio.h"
 #include "kernel_defines.h"
 
@@ -35,28 +35,32 @@ void led_init(void)
         return;
     }
 
-#ifdef LED0_PIN
+    /* The condition is dual: We don't init if the LED is absent (eg. when a
+     * LEDn_PIN is defined, but there is a higher level driver such as SAUL PWM that makes the
+     * direct use impossible), but we also don't init if there is no pin (eg.
+     * on native where there is a different mechanism for LEDs). */
+#if defined(LED0_IS_PRESENT) && defined(LED0_PIN)
     LED_INIT(0);
 #endif
-#ifdef LED1_PIN
+#if defined(LED1_IS_PRESENT) && defined(LED1_PIN)
     LED_INIT(1);
 #endif
-#ifdef LED2_PIN
+#if defined(LED2_IS_PRESENT) && defined(LED2_PIN)
     LED_INIT(2);
 #endif
-#ifdef LED3_PIN
+#if defined(LED3_IS_PRESENT) && defined(LED3_PIN)
     LED_INIT(3);
 #endif
-#ifdef LED4_PIN
+#if defined(LED4_IS_PRESENT) && defined(LED4_PIN)
     LED_INIT(4);
 #endif
-#ifdef LED5_PIN
+#if defined(LED5_IS_PRESENT) && defined(LED5_PIN)
     LED_INIT(5);
 #endif
-#ifdef LED6_PIN
+#if defined(LED6_IS_PRESENT) && defined(LED6_PIN)
     LED_INIT(6);
 #endif
-#ifdef LED7_PIN
+#if defined(LED7_IS_PRESENT) && defined(LED7_PIN)
     LED_INIT(7);
 #endif
 }