Add ADC support for STM32F3 and STM32F0 devices (#7681)

* Add ADC support for STM32F3 and STM32F0 devices

* Add section about configration options available to the ARM ADC implementation

* Fix STM32 typo

2 files changed, 264 insertions, 0 deletions

diff --git a/drivers/arm/analog.c b/drivers/arm/analog.c
new file mode 100644
index 0000000000..427381f281
--- /dev/null
+++ b/drivers/arm/analog.c
@@ -0,0 +1,207 @@
+/* Copyright 2019 Drew Mills
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "analog.h"
+#include "quantum.h"
+
+/* User configurable ADC options */
+#ifndef ADC_CIRCULAR_BUFFER
+#    define ADC_CIRCULAR_BUFFER FALSE
+#endif
+
+#ifndef ADC_NUM_CHANNELS
+#    define ADC_NUM_CHANNELS 1
+#elif ADC_NUM_CHANNELS != 1
+#    error "The ARM ADC implementation currently only supports reading one channel at a time."
+#endif
+
+#ifndef ADC_BUFFER_DEPTH
+#    define ADC_BUFFER_DEPTH 2
+#endif
+
+// For more sampling rate options, look at hal_adc_lld.h in ChibiOS
+#ifndef ADC_SAMPLING_RATE
+#    define ADC_SAMPLING_RATE ADC_SMPR_SMP_1P5
+#endif
+
+// Options are 12, 10, 8, and 6 bit.
+#ifndef ADC_RESOLUTION
+#    define ADC_RESOLUTION ADC_CFGR1_RES_12BIT
+#endif
+
+static ADCConfig   adcCfg = {};
+static adcsample_t sampleBuffer[ADC_NUM_CHANNELS * ADC_BUFFER_DEPTH];
+
+// Initialize to max number of ADCs, set to empty object to initialize all to false.
+#if defined(STM32F0XX)
+static bool adcInitialized[1] = {};
+#elif defined(STM32F3XX)
+static bool adcInitialized[4] = {};
+#else
+#    error "adcInitialized has not been implemented for this ARM microcontroller."
+#endif
+
+static ADCConversionGroup adcConversionGroup = {
+    ADC_CIRCULAR_BUFFER,
+    (uint16_t)(ADC_NUM_CHANNELS),
+    NULL,  // No end callback
+    NULL,  // No error callback
+#if defined(STM32F0XX)
+    ADC_CFGR1_CONT | ADC_RESOLUTION,
+    ADC_TR(0, 0).ADC_SAMPLING_RATE,
+    NULL,  // Doesn't specify a default channel
+#elif defined(STM32F3XX)
+    ADC_CFGR_CONT | ADC_RESOLUTION,
+    ADC_TR(0, 4095),
+    {
+        ADC_SAMPLING_RATE,
+        ADC_SAMPLING_RATE,
+    },
+    {
+        0,  // Doesn't specify a default channel
+        0,
+        0,
+        0,
+    },
+#endif
+};
+
+static inline ADCDriver* intToADCDriver(uint8_t adcInt) {
+    ADCDriver* target;
+
+    switch (adcInt) {
+        // clang-format off
+#if STM32_ADC_USE_ADC1
+        case 0: target = &ADCD1; break;
+#endif
+#if STM32_ADC_USE_ADC2
+        case 1: target = &ADCD2; break;
+#endif
+#if STM32_ADC_USE_ADC3
+        case 2: target = &ADCD3; break;
+#endif
+#if STM32_ADC_USE_ADC4
+        case 3: target = &ADCD4; break;
+#endif
+        default: target = NULL; break;
+            // clang-format on
+    }
+
+    return target;
+}
+
+static inline void manageAdcInitializationDriver(uint8_t adc, ADCDriver* adcDriver) {
+    if (!adcInitialized[adc]) {
+        adcStart(adcDriver, &adcCfg);
+        adcInitialized[adc] = true;
+    }
+}
+
+static inline void manageAdcInitialization(uint8_t adc) { manageAdcInitializationDriver(adc, intToADCDriver(adc)); }
+
+pin_and_adc pinToMux(pin_t pin) {
+    switch (pin) {
+        // clang-format off
+#if defined(STM32F0XX)
+        case A0:  return (pin_and_adc){ ADC_CHANNEL_IN0,  0 };
+        case A1:  return (pin_and_adc){ ADC_CHANNEL_IN1,  0 };
+        case A2:  return (pin_and_adc){ ADC_CHANNEL_IN2,  0 };
+        case A3:  return (pin_and_adc){ ADC_CHANNEL_IN3,  0 };
+        case A4:  return (pin_and_adc){ ADC_CHANNEL_IN4,  0 };
+        case A5:  return (pin_and_adc){ ADC_CHANNEL_IN5,  0 };
+        case A6:  return (pin_and_adc){ ADC_CHANNEL_IN6,  0 };
+        case A7:  return (pin_and_adc){ ADC_CHANNEL_IN7,  0 };
+        case B0:  return (pin_and_adc){ ADC_CHANNEL_IN8,  0 };
+        case B1:  return (pin_and_adc){ ADC_CHANNEL_IN9,  0 };
+        case C0:  return (pin_and_adc){ ADC_CHANNEL_IN10, 0 };
+        case C1:  return (pin_and_adc){ ADC_CHANNEL_IN11, 0 };
+        case C2:  return (pin_and_adc){ ADC_CHANNEL_IN12, 0 };
+        case C3:  return (pin_and_adc){ ADC_CHANNEL_IN13, 0 };
+        case C4:  return (pin_and_adc){ ADC_CHANNEL_IN14, 0 };
+        case C5:  return (pin_and_adc){ ADC_CHANNEL_IN15, 0 };
+#elif defined(STM32F3XX)
+        case A0:  return (pin_and_adc){ ADC_CHANNEL_IN1,  0 };
+        case A1:  return (pin_and_adc){ ADC_CHANNEL_IN2,  0 };
+        case A2:  return (pin_and_adc){ ADC_CHANNEL_IN3,  0 };
+        case A3:  return (pin_and_adc){ ADC_CHANNEL_IN4,  0 };
+        case A4:  return (pin_and_adc){ ADC_CHANNEL_IN1,  1 };
+        case A5:  return (pin_and_adc){ ADC_CHANNEL_IN2,  1 };
+        case A6:  return (pin_and_adc){ ADC_CHANNEL_IN3,  1 };
+        case A7:  return (pin_and_adc){ ADC_CHANNEL_IN4,  1 };
+        case B0:  return (pin_and_adc){ ADC_CHANNEL_IN12, 2 };
+        case B1:  return (pin_and_adc){ ADC_CHANNEL_IN1,  2 };
+        case B2:  return (pin_and_adc){ ADC_CHANNEL_IN12, 1 };
+        case B12: return (pin_and_adc){ ADC_CHANNEL_IN2,  3 };
+        case B13: return (pin_and_adc){ ADC_CHANNEL_IN3,  3 };
+        case B14: return (pin_and_adc){ ADC_CHANNEL_IN4,  3 };
+        case B15: return (pin_and_adc){ ADC_CHANNEL_IN5,  3 };
+        case C0:  return (pin_and_adc){ ADC_CHANNEL_IN6,  0 }; // Can also be ADC2
+        case C1:  return (pin_and_adc){ ADC_CHANNEL_IN7,  0 }; // Can also be ADC2
+        case C2:  return (pin_and_adc){ ADC_CHANNEL_IN8,  0 }; // Can also be ADC2
+        case C3:  return (pin_and_adc){ ADC_CHANNEL_IN9,  0 }; // Can also be ADC2
+        case C4:  return (pin_and_adc){ ADC_CHANNEL_IN5,  1 };
+        case C5:  return (pin_and_adc){ ADC_CHANNEL_IN11, 1 };
+        case D8:  return (pin_and_adc){ ADC_CHANNEL_IN12, 3 };
+        case D9:  return (pin_and_adc){ ADC_CHANNEL_IN13, 3 };
+        case D10: return (pin_and_adc){ ADC_CHANNEL_IN7,  2 }; // Can also be ADC4
+        case D11: return (pin_and_adc){ ADC_CHANNEL_IN8,  2 }; // Can also be ADC4
+        case D12: return (pin_and_adc){ ADC_CHANNEL_IN9,  2 }; // Can also be ADC4
+        case D13: return (pin_and_adc){ ADC_CHANNEL_IN10, 2 }; // Can also be ADC4
+        case D14: return (pin_and_adc){ ADC_CHANNEL_IN11, 2 }; // Can also be ADC4
+        case E7:  return (pin_and_adc){ ADC_CHANNEL_IN13, 2 };
+        case E8:  return (pin_and_adc){ ADC_CHANNEL_IN6,  2 }; // Can also be ADC4
+        case E9:  return (pin_and_adc){ ADC_CHANNEL_IN2,  2 };
+        case E10: return (pin_and_adc){ ADC_CHANNEL_IN14, 2 };
+        case E11: return (pin_and_adc){ ADC_CHANNEL_IN15, 2 };
+        case E12: return (pin_and_adc){ ADC_CHANNEL_IN16, 2 };
+        case E13: return (pin_and_adc){ ADC_CHANNEL_IN3,  2 };
+        case E14: return (pin_and_adc){ ADC_CHANNEL_IN1,  3 };
+        case E15: return (pin_and_adc){ ADC_CHANNEL_IN2,  3 };
+        case F2:  return (pin_and_adc){ ADC_CHANNEL_IN10, 0 }; // Can also be ADC2
+        case F4:  return (pin_and_adc){ ADC_CHANNEL_IN5,  0 };
+#else
+#error "An ADC pin-to-mux configuration has not been specified for this microcontroller."
+#endif
+        default:  return (pin_and_adc){ 0, 0 };
+            // clang-format on
+    }
+}
+
+adcsample_t analogReadPin(pin_t pin) { return adc_read(pinToMux(pin)); }
+
+adcsample_t analogReadPinAdc(pin_t pin, uint8_t adc) {
+    pin_and_adc target = pinToMux(pin);
+    target.adc         = adc;
+    return adc_read(target);
+}
+
+adcsample_t adc_read(pin_and_adc mux) {
+#if defined(STM32F0XX)
+    adcConversionGroup.sqr = ADC_CHSELR_CHSEL1;
+#elif defined(STM32F3XX)
+    adcConversionGroup.sqr[0] = ADC_SQR1_SQ1_N(mux.pin);
+#else
+#    error "adc_read has not been updated to support this ARM microcontroller."
+#endif
+
+    ADCDriver* targetDriver = intToADCDriver(mux.adc);
+    manageAdcInitializationDriver(mux.adc, targetDriver);
+
+    adcConvert(targetDriver, &adcConversionGroup, &sampleBuffer[0], ADC_BUFFER_DEPTH);
+    adcsample_t* result = sampleBuffer;
+
+    return *result;
+}
diff --git a/drivers/arm/analog.h b/drivers/arm/analog.h
new file mode 100644
index 0000000000..ab592ada33
--- /dev/null
+++ b/drivers/arm/analog.h
@@ -0,0 +1,57 @@
+/* Copyright 2019 Drew Mills
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "quantum.h"
+#include "ch.h"
+#include <hal.h>
+
+#if !defined(STM32F0XX) && !defined(STM32F3XX)
+#    error "Only STM23F0 and STM32F3 devices have ADC support in QMK at this time."
+#endif
+
+#if !HAL_USE_ADC
+#    error "You need to set HAL_USE_ADC to TRUE in your halconf.h to use the ADC."
+#endif
+
+#if !STM32_ADC_USE_ADC1 && !STM32_ADC_USE_ADC2 && !STM32_ADC_USE_ADC3 && !STM32_ADC_USE_ADC4
+#    error "You need to set one of the 'STM32_ADC_USE_ADCx' settings to TRUE in your mcuconf.h to use the ADC."
+#endif
+
+#if STM32_ADC_DUAL_MODE
+#    error "STM32 ADC Dual Mode is not supported at this time."
+#endif
+
+#if STM32_ADCV3_OVERSAMPLING
+#    error "STM32 ADCV3 Oversampling is not supported at this time."
+#endif
+
+typedef struct {
+    pin_t   pin;
+    uint8_t adc;
+} pin_and_adc;
+#define PIN_AND_ADC(p, a) \
+    (pin_and_adc) { p, a }
+
+// analogReference has been left un-defined for ARM devices.
+// void analogReference(uint8_t mode);
+
+adcsample_t analogReadPin(pin_t pin);
+adcsample_t analogReadPinAdc(pin_t pin, uint8_t adc);
+pin_and_adc pinToMux(pin_t pin);
+
+adcsample_t adc_read(pin_and_adc mux);