stm32f0: New target STM32F0 added.

Signed-off-by: Eugene Krashtan <Eugene.Krashtan@opensynergy.com>

src/stm32f0/adc.c

@@ -0,0 +1,164 @@
+/*
+ *  ADC functions on STM32F0
+ *
+ *  Copyright (C) 2019 Eug Krashtan <eug.krashtan@gmail.com>
+ *  This file may be distributed under the terms of the GNU GPLv3 license.
+ *
+ */
+
+#include <stdbool.h> // bool
+#include "board/gpio.h" // gpio_adc_setup
+#include "board/io.h" // readb
+#include "stm32f0xx_hal.h"
+#include "internal.h" // GPIO
+#include "compiler.h" // ARRAY_SIZE
+#include "command.h" // shutdown
+#include "sched.h" // sched_shutdown
+
+DECL_CONSTANT("ADC_MAX", 4095);
+
+#define ADC_DELAY (240 * 8)
+static bool adc_busy;
+static uint8_t adc_current_channel;
+ADC_HandleTypeDef hadc;
+
+static const uint8_t adc_pins[] = {
+    GPIO('A', 0), GPIO('A', 1),
+#if !(CONFIG_SERIAL)
+    GPIO('A', 2), GPIO('A', 3),
+#endif
+    GPIO('A', 4), GPIO('A', 5), GPIO('A', 6), GPIO('A', 7),
+    GPIO('B', 1),
+    // Fake ADC on this GPIO (returns tempsensor value)
+    GPIO('B', 8)
+};
+
+static const uint32_t adc_channels[] = {
+    ADC_CHANNEL_0,
+    ADC_CHANNEL_1,
+#if !(CONFIG_SERIAL)
+    ADC_CHANNEL_2,
+    ADC_CHANNEL_3,
+#endif
+    ADC_CHANNEL_4,
+    ADC_CHANNEL_5,
+    ADC_CHANNEL_6,
+    ADC_CHANNEL_7,
+    ADC_CHANNEL_9,
+    // For tests
+    ADC_CHANNEL_TEMPSENSOR
+};
+
+struct gpio_adc
+gpio_adc_setup(uint8_t pin)
+{
+    // Find pin in adc_pins table
+    int chan;
+    ADC_ChannelConfTypeDef sConfig = {0};
+    for (chan=0; ; chan++) {
+        if (chan >= ARRAY_SIZE(adc_pins))
+            shutdown("Not a valid ADC pin");
+        if (adc_pins[chan] == pin) {
+            sConfig.Channel = adc_channels[chan];
+            break;
+        }
+    }
+
+    /**ADC GPIO Configuration
+    */
+    GPIO_InitTypeDef GPIO_InitStruct = {0};
+    GPIO_InitStruct.Pin = 1 << (pin % 16);;
+    GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
+    GPIO_InitStruct.Pull = GPIO_NOPULL;
+    HAL_GPIO_Init((pin<8)?GPIOA:GPIOB, &GPIO_InitStruct);
+    /**Configure for the selected ADC regular channel to be converted.
+    */
+    sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;
+    sConfig.SamplingTime = ADC_SAMPLETIME_239CYCLES_5;
+    HAL_ADC_ConfigChannel(&hadc, &sConfig);
+    HAL_ADCEx_Calibration_Start(&hadc);
+    return (struct gpio_adc){ .pin = adc_channels[chan] };
+}
+
+// Try to sample a value. Returns zero if sample ready, otherwise
+// returns the number of clock ticks the caller should wait before
+// retrying this function.
+uint32_t
+gpio_adc_sample(struct gpio_adc g)
+{
+    /* ADC not busy, start conversion */
+    if (!readb(&adc_busy)) {
+        HAL_ADC_Start(&hadc);
+        adc_busy = true;
+        adc_current_channel = g.pin;
+        return ADC_DELAY;
+    /* ADC finished conversion for this channel */
+    } else if (HAL_ADC_PollForConversion(&hadc, 100) == HAL_OK) {
+        __HAL_ADC_CLEAR_FLAG(&hadc, ADC_FLAG_EOS);
+        adc_busy = false;
+        return 0;
+    }
+    /* Wants to sample another channel, or not finished yet */
+    return ADC_DELAY;
+}
+
+// Read a value; use only after gpio_adc_sample() returns zero
+uint16_t
+gpio_adc_read(struct gpio_adc g)
+{
+    return HAL_ADC_GetValue(&hadc);
+}
+
+// Cancel a sample that may have been started with gpio_adc_sample()
+void
+gpio_adc_cancel_sample(struct gpio_adc g)
+{
+    if (readb(&adc_busy) && readl(&adc_current_channel) == g.pin) {
+        adc_busy = false;
+        HAL_ADC_Stop(&hadc);
+    }
+}
+
+/**
+  * @brief ADC Initialization Function
+  * @param None
+  * @retval None
+  */
+void AdcInit(void)
+{
+    /**Configure the global features of the ADC (Clock,
+     * Resolution, Data Alignment and number of conversion)
+    */
+    hadc.Instance = ADC1;
+    hadc.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV1;
+    hadc.Init.Resolution = ADC_RESOLUTION_12B;
+    hadc.Init.DataAlign = ADC_DATAALIGN_RIGHT;
+    hadc.Init.ScanConvMode = ADC_SCAN_DIRECTION_FORWARD;
+    hadc.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
+    hadc.Init.LowPowerAutoWait = DISABLE;
+    hadc.Init.LowPowerAutoPowerOff = DISABLE;
+    hadc.Init.ContinuousConvMode = DISABLE;
+    hadc.Init.DiscontinuousConvMode = DISABLE;
+    hadc.Init.ExternalTrigConv = ADC_SOFTWARE_START;
+    hadc.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
+    hadc.Init.DMAContinuousRequests = DISABLE;
+    hadc.Init.Overrun = ADC_OVR_DATA_OVERWRITTEN;
+    HAL_ADC_Init(&hadc);
+}
+DECL_INIT(AdcInit);
+
+
+/**
+* @brief ADC MSP Initialization
+* @param hadc: ADC handle pointer
+* @retval None
+*/
+void HAL_ADC_MspInit(ADC_HandleTypeDef* hadc)
+{
+    if(hadc->Instance==ADC1)
+    {
+        /* Peripheral clock enable */
+        __HAL_RCC_ADC1_CLK_ENABLE();
+        __HAL_RCC_GPIOA_CLK_ENABLE();
+    }
+}