ESP32S2: Support for FrequencyIO

ports/esp32s2/Makefile

@@ -188,6 +188,7 @@ SRC_C += \
 	lib/utils/pyexec.c \
 	lib/utils/stdout_helpers.c \
 	lib/utils/sys_stdio_mphal.c \
+	peripherals/timer.c \
 	peripherals/pcnt.c \
 	peripherals/pins.c \
 	peripherals/rmt.c \

ports/esp32s2/common-hal/frequencyio/FrequencyIn.c

@@ -0,0 +1,193 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 microDev
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "shared-bindings/frequencyio/FrequencyIn.h"
+
+#include "py/runtime.h"
+
+static void IRAM_ATTR pcnt_overflow_handler(void *self_in) {
+    frequencyio_frequencyin_obj_t * self = self_in;
+    // reset counter
+    pcnt_counter_clear(self->unit);
+
+    // increase multiplier
+    self->multiplier++;
+
+    // reset interrupt
+    PCNT.int_clr.val = BIT(self->unit);
+}
+
+static void IRAM_ATTR timer_interrupt_handler(void *self_in) {
+    frequencyio_frequencyin_obj_t * self = self_in;
+    // get counter value
+    int16_t count;
+    pcnt_get_counter_value(self->unit, &count);
+    self->frequency = ((count / 2.0) + (self->multiplier * INT16_MAX / 4.0)) / (self->capture_period);
+
+    // reset multiplier
+    self->multiplier = 0;
+
+    // reset counter
+    pcnt_counter_clear(self->unit);
+
+    // reset interrupt
+    timg_dev_t *device = self->timer.group ? &(TIMERG1) : &(TIMERG0);
+    if (self->timer.idx) {
+        device->int_clr.t1 = 1;
+    } else {
+        device->int_clr.t0 = 1;
+    }
+    device->hw_timer[self->timer.idx].config.alarm_en = 1;
+}
+
+static void init_pcnt(frequencyio_frequencyin_obj_t* self) {
+    // Prepare configuration for the PCNT unit
+    const pcnt_config_t pcnt_config = {
+        // Set PCNT input signal and control GPIOs
+        .pulse_gpio_num = self->pin,
+        .ctrl_gpio_num = PCNT_PIN_NOT_USED,
+        .channel = PCNT_CHANNEL_0,
+        // What to do on the positive / negative edge of pulse input?
+        .pos_mode = PCNT_COUNT_INC,  // count both rising and falling edges
+        .neg_mode = PCNT_COUNT_INC,
+        // Set counter limit
+        .counter_h_lim = INT16_MAX,
+        .counter_l_lim = 0,
+    };
+
+    // initialize PCNT
+    const int8_t unit = peripherals_pcnt_init(pcnt_config);
+    if (unit == -1) {
+        mp_raise_RuntimeError(translate("All PCNT units in use"));
+    }
+
+    // set the GPIO back to high-impedance, as pcnt_unit_config sets it as pull-up
+    gpio_set_pull_mode(self->pin, GPIO_FLOATING);
+
+    self->unit = (pcnt_unit_t)unit;
+
+    // enable pcnt interrupt
+    pcnt_event_enable(self->unit, PCNT_EVT_H_LIM);
+    pcnt_isr_register(pcnt_overflow_handler, (void *)self, ESP_INTR_FLAG_IRAM, &self->handle);
+    pcnt_intr_enable(self->unit);
+}
+
+static void init_timer(frequencyio_frequencyin_obj_t* self) {
+    // Prepare configuration for the timer module
+    const timer_config_t config = {
+        .alarm_en = true,
+        .counter_en = false,
+        .intr_type = TIMER_INTR_LEVEL,
+        .counter_dir = TIMER_COUNT_UP,
+        .auto_reload = true,
+        .divider = 80            // 1 us per tick
+    };
+
+    // initialize Timer
+    peripherals_timer_init(&config, &self->timer);
+    if (self->timer.idx == TIMER_MAX || self->timer.group == TIMER_GROUP_MAX) {
+        mp_raise_RuntimeError(translate("All timers in use"));
+    }
+
+    timer_idx_t idx = self->timer.idx;
+    timer_group_t group = self->timer.group;
+
+    // enable timer interrupt
+    timer_set_alarm_value(group, idx, self->capture_period * 1000000);
+    timer_isr_register(group, idx, timer_interrupt_handler, (void *)self, ESP_INTR_FLAG_IRAM, &self->handle);
+    timer_enable_intr(group, idx);
+
+    // start timer
+    timer_start(self->timer.group, self->timer.idx);
+}
+
+void common_hal_frequencyio_frequencyin_construct(frequencyio_frequencyin_obj_t* self,
+        const mcu_pin_obj_t* pin, const uint16_t capture_period) {
+    if ((capture_period == 0) || (capture_period > 500)) {
+        mp_raise_ValueError(translate("Invalid capture period. Valid range: 1 - 500"));
+    }
+
+    self->pin = pin->number;
+    self->handle = NULL;
+    self->multiplier = 0;
+    self->capture_period = capture_period;
+
+    // initialize pcnt and timer
+    init_pcnt(self);
+    init_timer(self);
+
+    claim_pin(pin);
+}
+
+bool common_hal_frequencyio_frequencyin_deinited(frequencyio_frequencyin_obj_t* self) {
+    return self->unit == PCNT_UNIT_MAX;
+}
+
+void common_hal_frequencyio_frequencyin_deinit(frequencyio_frequencyin_obj_t* self) {
+    if (common_hal_frequencyio_frequencyin_deinited(self)) {
+        return;
+    }
+    reset_pin_number(self->pin);
+    peripherals_pcnt_deinit(&self->unit);
+    peripherals_timer_deinit(&self->timer);
+    if (self->handle) {
+        esp_intr_free(self->handle);
+        self->handle = NULL;
+    }
+}
+
+uint32_t common_hal_frequencyio_frequencyin_get_item(frequencyio_frequencyin_obj_t* self) {
+    return self->frequency;
+}
+
+void common_hal_frequencyio_frequencyin_pause(frequencyio_frequencyin_obj_t* self) {
+    pcnt_counter_pause(self->unit);
+    timer_pause(self->timer.group, self->timer.idx);
+}
+
+void common_hal_frequencyio_frequencyin_resume(frequencyio_frequencyin_obj_t* self) {
+    pcnt_counter_resume(self->unit);
+    timer_start(self->timer.group, self->timer.idx);
+}
+
+void common_hal_frequencyio_frequencyin_clear(frequencyio_frequencyin_obj_t* self) {
+    self->frequency = 0;
+    pcnt_counter_clear(self->unit);
+    timer_set_counter_value(self->timer.group, self->timer.idx, 0);
+}
+
+uint16_t common_hal_frequencyio_frequencyin_get_capture_period(frequencyio_frequencyin_obj_t *self) {
+    return self->capture_period;
+}
+
+void common_hal_frequencyio_frequencyin_set_capture_period(frequencyio_frequencyin_obj_t *self, uint16_t capture_period) {
+    if ((capture_period == 0) || (capture_period > 500)) {
+        mp_raise_ValueError(translate("Invalid capture period. Valid range: 1 - 500"));
+    }
+    self->capture_period = capture_period;
+    common_hal_frequencyio_frequencyin_clear(self);
+    timer_set_alarm_value(self->timer.group, self->timer.idx, capture_period * 1000000);
+}

ports/esp32s2/common-hal/frequencyio/FrequencyIn.h

@@ -0,0 +1,45 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 microDev
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_ESP32S2_COMMON_HAL_FREQUENCYIO_FREQUENCYIN_H
+#define MICROPY_INCLUDED_ESP32S2_COMMON_HAL_FREQUENCYIO_FREQUENCYIN_H
+
+#include "py/obj.h"
+#include "peripherals/pcnt.h"
+#include "peripherals/timer.h"
+
+typedef struct {
+    mp_obj_base_t base;
+    pcnt_unit_t unit;
+    timer_index_t timer;
+    intr_handle_t handle;
+    uint8_t pin;
+    uint8_t multiplier;
+    uint32_t frequency;
+    uint16_t capture_period;
+} frequencyio_frequencyin_obj_t;
+
+#endif // MICROPY_INCLUDED_ESP32S2_COMMON_HAL_FREQUENCYIO_FREQUENCYIN_H

ports/esp32s2/common-hal/frequencyio/__init__.c

@@ -0,0 +1 @@
+// No ferquencyio module functions.

ports/esp32s2/mpconfigport.mk

@@ -18,7 +18,7 @@ CIRCUITPY_AUDIOBUSIO = 0
 CIRCUITPY_AUDIOIO = 0
 CIRCUITPY_CANIO = 1
 CIRCUITPY_COUNTIO = 1
-CIRCUITPY_FREQUENCYIO = 0
+CIRCUITPY_FREQUENCYIO = 1
 CIRCUITPY_I2CPERIPHERAL = 0
 CIRCUITPY_ROTARYIO = 1
 CIRCUITPY_NVM = 0

ports/esp32s2/peripherals/timer.c

@@ -0,0 +1,76 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 microDev
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "peripherals/timer.h"
+
+#define TIMER_FREE 1
+#define TIMER_BUSY 0
+
+static uint8_t timer_state[2][2];
+
+void peripherals_timer_reset(void) {
+    timer_index_t timer;
+    for (uint8_t i = 0; i < 2; i++) {
+        for (uint8_t j = 0; j < 2; j++) {
+            if (timer_state[i][j] == TIMER_BUSY) {
+                timer.idx = (timer_idx_t)j;
+                timer.group = (timer_group_t)i;
+                timer_state[i][j] = TIMER_FREE;
+                peripherals_timer_deinit(&timer);
+            }
+        }
+    }
+}
+
+void peripherals_timer_init(const timer_config_t * config, timer_index_t * timer) {
+    bool break_loop = false;
+
+    // get free timer
+    for (uint8_t i = 0; i < 2; i++) {
+        for (uint8_t j = 0; j < 2; j++) {
+            if (timer_state[i][j] == TIMER_FREE) {
+                timer->idx = (timer_idx_t)j;
+                timer->group = (timer_group_t)i;
+                timer_state[i][j] = TIMER_BUSY;
+                break_loop = true;
+                break;
+            } else if (i == 1 && j == 1) {
+                timer->idx = TIMER_MAX;
+                timer->group = TIMER_GROUP_MAX;
+                return;
+            }
+        }
+        if (break_loop) {break;}
+    }
+
+    // initialize timer module
+    timer_init(timer->group, timer->idx, config);
+    timer_set_counter_value(timer->group, timer->idx, 0);
+}
+
+void peripherals_timer_deinit(timer_index_t * timer) {
+    timer_deinit(timer->group, timer->idx);
+}

ports/esp32s2/peripherals/timer.h

@@ -0,0 +1,41 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 microDev
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_ESP32S2_PERIPHERALS_TIMER_HANDLER_H
+#define MICROPY_INCLUDED_ESP32S2_PERIPHERALS_TIMER_HANDLER_H
+
+#include "driver/timer.h"
+
+typedef struct {
+    timer_idx_t idx;
+    timer_group_t group;
+} timer_index_t;
+
+extern void peripherals_timer_init(const timer_config_t * config, timer_index_t * timer);
+extern void peripherals_timer_deinit(timer_index_t * timer);
+extern void peripherals_timer_reset(void);
+
+#endif  // MICROPY_INCLUDED_ESP32S2_PERIPHERALS_TIMER_HANDLER_H