alif/machine_adc: Add basic ADC support.

ADC12 information has been added to pin struct.

Signed-off-by: Damien George <damien@micropython.org>

Author: dpgeorge

ports/alif/Makefile

@@ -176,6 +176,7 @@ ALIF_SRC_C += $(addprefix $(ALIF_DFP_REL_TOP)/,\
 	Device/common/source/system_M55.c \
 	Device/common/source/system_utils.c \
 	Device/core/$(MCU_CORE)/source/startup_$(MCU_CORE).c \
+	drivers/source/adc.c \
 	drivers/source/mhu_driver.c \
 	drivers/source/mhu_receiver.c \
 	drivers/source/mhu_sender.c \

ports/alif/irq.h

@@ -43,6 +43,7 @@
 #define IRQ_PRI_MHU             NVIC_EncodePriority(NVIC_PRIORITYGROUP_7, 0, 0)
 #define IRQ_PRI_QUIET_TIMING    NVIC_EncodePriority(NVIC_PRIORITYGROUP_7, 1, 0)
 #define IRQ_PRI_UART_REPL       NVIC_EncodePriority(NVIC_PRIORITYGROUP_7, 1, 0)
+#define IRQ_PRI_ADC             NVIC_EncodePriority(NVIC_PRIORITYGROUP_7, 3, 0)
 #define IRQ_PRI_USB             NVIC_EncodePriority(NVIC_PRIORITYGROUP_7, 5, 0)
 #define IRQ_PRI_PENDSV          NVIC_EncodePriority(NVIC_PRIORITYGROUP_7, 127, 0)
 

ports/alif/machine_adc.c

@@ -0,0 +1,225 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2024 OpenMV LLC.
+ *
+ * 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.
+ */
+
+// This file is never compiled standalone, it's included directly from
+// extmod/machine_adc.c via MICROPY_PY_MACHINE_ADC_INCLUDEFILE.
+
+#include "py/mphal.h"
+
+#include "analog_config.h"
+#include "adc.h"
+#include "sys_ctrl_adc.h"
+
+#define ADC_CHANNEL_TEMP_SENSOR (6)
+#define ADC_CHANNEL_INT_VREF (7)
+
+static const uint8_t adc_instance_table[4] = {
+    ADC_INSTANCE_ADC12_0,
+    ADC_INSTANCE_ADC12_1,
+    ADC_INSTANCE_ADC12_2,
+    ADC_INSTANCE_ADC24_0,
+};
+
+static ADC_Type *const adc_regs_table[4] = {
+    (ADC_Type *)ADC120_BASE,
+    (ADC_Type *)ADC121_BASE,
+    (ADC_Type *)ADC122_BASE,
+    (ADC_Type *)ADC24_BASE,
+};
+
+static bool adc_inited[4];
+static conv_info_t adc_conv_info_table[4];
+
+static void adc_nvic_config(unsigned int irq) {
+    NVIC_ClearPendingIRQ(irq);
+    NVIC_SetPriority(irq, IRQ_PRI_ADC);
+    NVIC_EnableIRQ(irq);
+}
+
+static void adc_init(uint8_t adc_periph) {
+    if (adc_inited[adc_periph]) {
+        return;
+    }
+
+    ADC_Type *regs = adc_regs_table[adc_periph];
+    uint8_t adc_instance = adc_instance_table[adc_periph];
+    conv_info_t *conv_info = &adc_conv_info_table[adc_periph];
+
+    adc_set_clk_control(adc_instance, true);
+    enable_cmp_periph_clk();
+    analog_config_vbat_reg2();
+    analog_config_cmp_reg2();
+    adc_set_differential_ctrl(adc_instance, false);
+    adc_set_comparator_ctrl(adc_instance, true, 2);
+
+    if (adc_instance == ADC_INSTANCE_ADC24_0) {
+        enable_adc24();
+        set_adc24_output_rate(0);
+        set_adc24_bias(0);
+    } else {
+        adc_set_sample_width(regs, 32);
+    }
+
+    adc_set_clk_div(regs, 4);
+    adc_set_avg_sample(regs, 32);
+    adc_set_n_shift_bit(regs, 1, 1);
+    adc_set_single_ch_scan_mode(regs, conv_info);
+    adc_unmask_interrupt(regs);
+
+    adc_nvic_config(ADC120_DONE0_IRQ_IRQn);
+    adc_nvic_config(ADC120_DONE1_IRQ_IRQn);
+    adc_nvic_config(ADC121_DONE0_IRQ_IRQn);
+    adc_nvic_config(ADC121_DONE1_IRQ_IRQn);
+    adc_nvic_config(ADC122_DONE0_IRQ_IRQn);
+    adc_nvic_config(ADC122_DONE1_IRQ_IRQn);
+}
+
+static uint16_t adc_config_and_read_u16(unsigned int adc_periph, uint32_t channel) {
+    ADC_Type *adc_regs = adc_regs_table[adc_periph];
+    conv_info_t *conv_info = &adc_conv_info_table[adc_periph];
+
+    conv_info->status = ADC_CONV_STAT_NONE;
+    conv_info->mode = ADC_CONV_MODE_SINGLE_SHOT;
+
+    // Select channel and start conversion.
+    adc_init_channel_select(adc_regs, channel);
+    adc_set_single_ch_scan_mode(adc_regs, conv_info);
+    adc_enable_single_shot_conv(adc_regs);
+
+    // Wait for conversion to complete.
+    while (!(conv_info->status & ADC_CONV_STAT_COMPLETE)) {
+        __WFE();
+    }
+
+    return conv_info->sampled_value;
+}
+
+static void adc_done0_irq_handler_helper(unsigned int adc_periph) {
+    adc_done0_irq_handler(adc_regs_table[adc_periph], &adc_conv_info_table[adc_periph]);
+}
+
+static void adc_done1_irq_handler_helper(unsigned int adc_periph) {
+    adc_done1_irq_handler(adc_regs_table[adc_periph], &adc_conv_info_table[adc_periph]);
+}
+
+void ADC120_DONE0_IRQHandler(void) {
+    adc_done0_irq_handler_helper(0);
+    __SEV();
+}
+
+void ADC120_DONE1_IRQHandler(void) {
+    adc_done1_irq_handler_helper(0);
+    __SEV();
+}
+
+void ADC121_DONE0_IRQHandler(void) {
+    adc_done0_irq_handler_helper(1);
+    __SEV();
+}
+
+void ADC121_DONE1_IRQHandler(void) {
+    adc_done1_irq_handler_helper(1);
+    __SEV();
+}
+
+void ADC122_DONE0_IRQHandler(void) {
+    adc_done0_irq_handler_helper(2);
+    __SEV();
+}
+
+void ADC122_DONE1_IRQHandler(void) {
+    adc_done1_irq_handler_helper(2);
+    __SEV();
+}
+
+/******************************************************************************/
+// MicroPython bindings for machine.ADC
+
+#define MICROPY_PY_MACHINE_ADC_CLASS_CONSTANTS \
+    { MP_ROM_QSTR(MP_QSTR_CORE_TEMP), MP_ROM_INT(ADC_CHANNEL_TEMP_SENSOR) }, \
+    { MP_ROM_QSTR(MP_QSTR_CORE_VREF), MP_ROM_INT(ADC_CHANNEL_INT_VREF) }, \
+
+typedef struct _machine_adc_obj_t {
+    mp_obj_base_t base;
+    uint8_t adc_periph;
+    uint8_t adc_channel;
+} machine_adc_obj_t;
+
+static void mp_machine_adc_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
+    machine_adc_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    mp_printf(print, "<ADC12%u channel=%u>", self->adc_periph, self->adc_channel);
+}
+
+// ADC(id)
+static mp_obj_t mp_machine_adc_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
+    // Check number of arguments
+    mp_arg_check_num(n_args, n_kw, 1, 1, false);
+
+    mp_obj_t source = all_args[0];
+
+    uint8_t adc_periph;
+    uint8_t adc_channel;
+    const machine_pin_obj_t *pin = NULL;
+
+    if (mp_obj_is_int(source)) {
+        // Get and validate channel number.
+        adc_channel = mp_obj_get_int(source);
+        if (adc_channel < ADC_CHANNEL_TEMP_SENSOR) {
+            adc_periph = 0;
+        } else if (adc_channel == ADC_CHANNEL_TEMP_SENSOR || adc_channel == ADC_CHANNEL_INT_VREF) {
+            adc_periph = 2;
+        } else {
+            mp_raise_ValueError(MP_ERROR_TEXT("invalid channel"));
+        }
+    } else {
+        // Get GPIO and check it has ADC capabilities.
+        pin = mp_hal_get_pin_obj(source);
+        if (pin->adc12_periph <= 2 && pin->adc12_channel <= 5) {
+            // Select the ADC12 peripheral and channel.
+            adc_periph = pin->adc12_periph;
+            adc_channel = pin->adc12_channel;
+            // Configure the pad for analog input.
+            pinconf_set(pin->port, pin->pin, PINMUX_ALTERNATE_FUNCTION_7, PADCTRL_READ_ENABLE);
+        } else {
+            mp_raise_ValueError(MP_ERROR_TEXT("Pin doesn't have ADC capabilities"));
+        }
+    }
+
+    // Initialise the ADC peripheral.
+    adc_init(adc_periph);
+
+    // Create ADC object.
+    machine_adc_obj_t *o = mp_obj_malloc(machine_adc_obj_t, &machine_adc_type);
+    o->adc_periph = adc_periph;
+    o->adc_channel = adc_channel;
+
+    return MP_OBJ_FROM_PTR(o);
+}
+
+// read_u16()
+static mp_int_t mp_machine_adc_read_u16(machine_adc_obj_t *self) {
+    return adc_config_and_read_u16(self->adc_periph, self->adc_channel);
+}

ports/alif/mcu/make-pins.py

@@ -10,20 +10,51 @@
 NUM_PORTS = 16
 NUM_PINS_PER_PORT = 8
 
+# Maps pad name to (adc12_periph, adc12_channel).
+ADC12_ANA_MAP = {
+    "P0_0": (0, 0),
+    "P0_1": (0, 1),
+    "P0_2": (0, 2),
+    "P0_3": (0, 3),
+    "P0_4": (0, 4),
+    "P0_5": (0, 5),
+    "P0_6": (1, 0),
+    "P0_7": (1, 1),
+    "P1_0": (1, 2),
+    "P1_1": (1, 3),
+    "P1_2": (1, 4),
+    "P1_3": (1, 5),
+    "P1_4": (2, 0),
+    "P1_5": (2, 1),
+    "P1_6": (2, 2),
+    "P1_7": (2, 3),
+    "P2_0": (2, 4),
+    "P2_1": (2, 5),
+}
+
 
 class AlifPin(boardgen.Pin):
     # Emit the struct which contains the pin instance.
     def definition(self):
         port, pin = self.name()[1:].split("_")
+        adc12_periph, adc12_channel = ADC12_ANA_MAP.get(self.name(), (3, 7))
         base = "LPGPIO_BASE" if port == "15" else "GPIO{}_BASE".format(port)
         return (
             "{{ "
             ".base = {{ .type = &machine_pin_type }}, "
             ".gpio = (GPIO_Type *){base}, "
             ".port = PORT_{port}, "
             ".pin = PIN_{pin}, "
+            ".adc12_periph = {adc12_periph}, "
+            ".adc12_channel = {adc12_channel}, "
             ".name = MP_QSTR_P{port}_{pin} "
-            "}}".format(port=port, pin=pin, base=base)
+            "}}".format(
+                port=port,
+                pin=pin,
+                base=base,
+                adc12_periph=adc12_periph,
+                adc12_channel=adc12_channel,
+            )
         )
 
     # Alif cpu names must be "Pn_m".

ports/alif/mpconfigport.h

@@ -101,6 +101,8 @@
 #define MICROPY_PY_MACHINE_BOOTLOADER           (1)
 #define MICROPY_PY_MACHINE_BARE_METAL_FUNCS     (1)
 #define MICROPY_PY_MACHINE_DISABLE_IRQ_ENABLE_IRQ (1)
+#define MICROPY_PY_MACHINE_ADC                  (1)
+#define MICROPY_PY_MACHINE_ADC_INCLUDEFILE      "ports/alif/machine_adc.c"
 #define MICROPY_PY_MACHINE_DHT_READINTO         (1)
 #define MICROPY_PY_MACHINE_PULSE                (1)
 #define MICROPY_PY_MACHINE_SOFTI2C              (1)

ports/alif/mphalport.h

@@ -85,6 +85,8 @@ typedef struct _machine_pin_obj_t {
     GPIO_Type *gpio;
     uint8_t port;
     uint8_t pin;
+    uint8_t adc12_periph : 2;
+    uint8_t adc12_channel : 3;
     qstr name;
 } machine_pin_obj_t;