stm32/adc: Fix reading internal ADC channels on G4 MCUs.

For STM32G4 series, the internal sensors are connected to:
- ADC1_IN16: Temperature sensor
- ADC1_IN17: Battery voltage monitoring
- ADC1_IN18: Internal voltage reference
but ADC_CHANNEL_TEMPSENSOR_ADC1, ADC_CHANNEL_VBAT,
ADC_CHANNEL_VREFINT are not defined as 16, 17, 18.

This commit converts channel 16, 17, 18 to ADC_CHANNEL_x in
adc_get_internal_channel().

Signed-off-by: Yuuki NAGAO <wf.yn386@gmail.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/ports/stm32/adc.c b/ports/stm32/adc.c
index fc0882286..93eaa93f0 100644
--- a/ports/stm32/adc.c
+++ b/ports/stm32/adc.c
@@ -220,6 +220,14 @@ static inline uint32_t adc_get_internal_channel(uint32_t channel) {
     if (channel == 16) {
         channel = ADC_CHANNEL_TEMPSENSOR;
     }
+    #elif defined(STM32G4)
+    if (channel == 16) {
+        channel = ADC_CHANNEL_TEMPSENSOR_ADC1;
+    } else if (channel == 17) {
+        channel = ADC_CHANNEL_VBAT;
+    } else if (channel == 18) {
+        channel = ADC_CHANNEL_VREFINT;
+    }
     #elif defined(STM32L4)
     if (channel == 0) {
         channel = ADC_CHANNEL_VREFINT;