cpu/esp32: port periph/dac to ESP-IDF dac API

cpu/esp32/include/periph_cpu.h

@@ -281,7 +281,7 @@ typedef enum {
 /**
  * @brief  Number of DAC channels that could be used at maximum.
  */
-#define DAC_NUMOF_MAX   2
+#define DAC_NUMOF_MAX   (SOC_DAC_PERIPH_NUM)
 
 /** @} */
 

cpu/esp32/periph/dac.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2019 Gunar Schorcht
+ * Copyright (C) 2022 Gunar Schorcht
  *
  * This file is subject to the terms and conditions of the GNU Lesser General
  * Public License v2.1. See the file LICENSE in the top level directory for more
@@ -22,108 +22,73 @@
 #include "board.h"
 #include "periph/dac.h"
 
-#include "adc_arch.h"
-#include "adc_ctrl.h"
 #include "esp_common.h"
-#include "gpio_arch.h"
-#include "soc/rtc_io_struct.h"
-#include "soc/rtc_cntl_struct.h"
-#include "soc/sens_reg.h"
-#include "soc/sens_struct.h"
+#include "soc/dac_periph.h"
+#include "esp_idf_api/dac.h"
 
 #define ENABLE_DEBUG 0
 #include "debug.h"
 
-/* declaration of external functions */
-extern void _adc2_ctrl_init(void);
-
 /* forward declarations of internal functions */
 static bool _dac_conf_check(void);
 static bool _dac_module_initialized  = false;
 
-/* external variable declarations */
-extern const gpio_t _gpio_rtcio_map[];
+/* RIOT DAC line to ESP-IDF channel map, filled during initialization */
+dac_channel_t _dac_channels[DAC_NUMOF] = { DAC_CHANNEL_MAX };
 
-int8_t dac_init (dac_t line)
+int8_t dac_init(dac_t line)
 {
-    CHECK_PARAM_RET (line < DAC_NUMOF, DAC_NOLINE)
-
     if (!_dac_module_initialized) {
-        /* do some configuration checks */
+        /* do some configuration checks and fill _dac_channel */
         if (!_dac_conf_check()) {
             return DAC_NOLINE;
         }
         _dac_module_initialized = true;
     }
 
-    _adc2_ctrl_init();
-
-    uint8_t rtcio = _gpio_rtcio_map[dac_channels[line]];
-    uint8_t idx;
-
-    /* try to initialize the pin as DAC output */
-    if (gpio_get_pin_usage(_adc_hw[rtcio].gpio) != _GPIO) {
-        LOG_TAG_ERROR("dac", "GPIO%d is used for %s and cannot be used as "
-                      "DAC output\n", _adc_hw[rtcio].gpio,
-                      gpio_get_pin_usage_str(_adc_hw[rtcio].gpio));
+    if ((line >= DAC_NUMOF) || (_dac_channels[line] == DAC_CHANNEL_MAX)) {
+        LOG_TAG_ERROR("dac", "Line %u is an invalid DAC line\n", line);
         return DAC_NOLINE;
     }
 
-    /* disable the output of the pad */
-    RTCIO.enable_w1tc.val = BIT(_adc_hw[rtcio].rtc_gpio);
-
-    switch (rtcio) {
-        case RTCIO_DAC1: /* GPIO25, RTC6 */
-        case RTCIO_DAC2: /* GPIO26, RTC7 */
-                idx = rtcio - RTCIO_DAC1;
-                RTCIO.pad_dac[idx].mux_sel = 1; /* route to RTC */
-                RTCIO.pad_dac[idx].fun_sel = 0; /* function ADC2_CH8, ADC2_CH9 */
-                RTCIO.pad_dac[idx].fun_ie = 0;  /* input disabled */
-                RTCIO.pad_dac[idx].rue = 0;     /* pull-up disabled */
-                RTCIO.pad_dac[idx].rde = 0;     /* pull-down disabled */
-
-                RTCIO.pad_dac[idx].dac_xpd_force = 1; /* use RTC pad not the FSM*/
-                RTCIO.pad_dac[idx].xpd_dac = 1;       /* DAC powered on */
-                break;
-
-        default: return DAC_NOLINE;
-    }
-
-    /* set pin usage type  */
-    gpio_set_pin_usage(_adc_hw[rtcio].gpio, _DAC);
-
-    /* don't use DMA */
-    SENS.sar_dac_ctrl1.dac_dig_force = 0;
-
-    /* disable CW generators and invert DAC signal */
-    SENS.sar_dac_ctrl1.sw_tone_en = 0;
-    SENS.sar_dac_ctrl2.dac_cw_en1 = 0;
-    SENS.sar_dac_ctrl2.dac_cw_en2 = 0;
+    dac_poweron(line);
+    dac_set(line, 0);
 
     return DAC_OK;
 }
 
-void dac_set (dac_t line, uint16_t value)
+void dac_set(dac_t line, uint16_t value)
 {
-    CHECK_PARAM (line < DAC_NUMOF);
-    RTCIO.pad_dac[_gpio_rtcio_map[dac_channels[line]] - RTCIO_DAC1].dac = value >> 8;
+    assert(line < DAC_NUMOF);
+    assert(_dac_channels[line] != DAC_CHANNEL_MAX);
+    esp_idf_dac_output_voltage(_dac_channels[line],
+                               value >> (16 - SOC_DAC_RESOLUTION));
 }
 
-void dac_poweroff (dac_t line)
+void dac_poweroff(dac_t line)
 {
-    CHECK_PARAM (line < DAC_NUMOF);
+    assert(line < DAC_NUMOF);
+    assert(_dac_channels[line] != DAC_CHANNEL_MAX);
+    esp_idf_dac_output_disable(_dac_channels[line]);
 }
 
-void dac_poweron (dac_t line)
+void dac_poweron(dac_t line)
 {
-    CHECK_PARAM (line < DAC_NUMOF);
+    assert(line < DAC_NUMOF);
+    assert(_dac_channels[line] != DAC_CHANNEL_MAX);
+    esp_idf_dac_output_enable(_dac_channels[line]);
 }
 
 static bool _dac_conf_check(void)
 {
     for (unsigned i = 0; i < DAC_NUMOF; i++) {
-        if (_gpio_rtcio_map[dac_channels[i]] != RTCIO_DAC1 &&
-            _gpio_rtcio_map[dac_channels[i]] != RTCIO_DAC2) {
+        for (unsigned j = 0; i < SOC_DAC_PERIPH_NUM; j++) {
+            if (dac_channels[i] == dac_periph_signal.dac_channel_io_num[j]) {
+                _dac_channels[i] = j;
+                break;
+            }
+        }
+        if (_dac_channels[i] == DAC_CHANNEL_MAX) {
             LOG_TAG_ERROR("dac", "GPIO%d cannot be used as DAC line\n",
                           dac_channels[i]);
             return false;