Defined IS_(HOST_)LED_ON/OFF() and improved LED documentation (#4853)

* Defined IS_(HOST_)LED_ON/OFF() and improved LED documentation

* Update docs/custom_quantum_functions.md

Co-Authored-By: DidierLoiseau <didierloiseau+github@gmail.com>

* Update docs/custom_quantum_functions.md

Co-Authored-By: DidierLoiseau <didierloiseau+github@gmail.com>

* Integrated @drashna and @fauxpark's PR comments

- changed all plurals of "LED" to "LEDs" in the file
- rewording of the note about host_keyboard_leds() vs. led_set_user()

* Update docs/custom_quantum_functions.md

Co-Authored-By: DidierLoiseau <didierloiseau+github@gmail.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/tmk_core/common/host.h b/tmk_core/common/host.h
index aeabba710..e70bb6853 100644
--- a/tmk_core/common/host.h
+++ b/tmk_core/common/host.h
@@ -46,6 +46,12 @@ void host_consumer_send(uint16_t data);
 uint16_t host_last_system_report(void);
 uint16_t host_last_consumer_report(void);
 
+#define IS_LED_ON(USB_LED, LED_NAME)    ((USB_LED) & (1 << (LED_NAME)))
+#define IS_LED_OFF(USB_LED, LED_NAME)   (~(USB_LED) & (1 << (LED_NAME)))
+
+#define IS_HOST_LED_ON(LED_NAME)     IS_LED_ON(host_keyboard_leds(), (LED_NAME))
+#define IS_HOST_LED_OFF(LED_NAME)    IS_LED_OFF(host_keyboard_leds(), (LED_NAME))
+
 #ifdef __cplusplus
 }
 #endif