1 /* 2 * Copyright (c) 2015 - 2018, Nordic Semiconductor ASA 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, this 9 * list of conditions and the following disclaimer. 10 * 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * 3. Neither the name of the copyright holder nor the names of its 16 * contributors may be used to endorse or promote products derived from this 17 * software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 20 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 23 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <nrfx.h> 33 34 #if NRFX_CHECK(NRFX_PDM_ENABLED) 35 36 #include <nrfx_pdm.h> 37 #include <hal/nrf_gpio.h> 38 39 #define NRFX_LOG_MODULE PDM 40 #include <nrfx_log.h> 41 42 #define EVT_TO_STR(event) \ 43 (event == NRF_PDM_EVENT_STARTED ? "NRF_PDM_EVENT_STARTED" : \ 44 (event == NRF_PDM_EVENT_STOPPED ? "NRF_PDM_EVENT_STOPPED" : \ 45 (event == NRF_PDM_EVENT_END ? "NRF_PDM_EVENT_END" : \ 46 "UNKNOWN EVENT"))) 47 48 49 /** @brief PDM interface status. */ 50 typedef enum 51 { 52 NRFX_PDM_STATE_IDLE, 53 NRFX_PDM_STATE_RUNNING, 54 NRFX_PDM_STATE_STARTING, 55 NRFX_PDM_STATE_STOPPING 56 } nrfx_pdm_state_t; 57 58 /** @brief PDM interface control block.*/ 59 typedef struct 60 { 61 nrfx_pdm_event_handler_t event_handler; ///< Event handler function pointer. 62 int16_t * buff_address[2]; ///< Sample buffers. 63 uint16_t buff_length[2]; ///< Length of the sample buffers. 64 nrfx_drv_state_t drv_state; ///< Driver state. 65 volatile nrfx_pdm_state_t op_state; ///< PDM peripheral operation state. 66 uint8_t active_buffer; ///< Number of currently active buffer. 67 uint8_t error; ///< Driver error flag. 68 volatile uint8_t irq_buff_request; ///< Request the next buffer in the ISR. 69 } nrfx_pdm_cb_t; 70 71 static nrfx_pdm_cb_t m_cb; 72 73 74 void nrfx_pdm_irq_handler(void) 75 { 76 if (nrf_pdm_event_check(NRF_PDM_EVENT_STARTED)) 77 { 78 nrf_pdm_event_clear(NRF_PDM_EVENT_STARTED); 79 NRFX_LOG_DEBUG("Event: %s.", EVT_TO_STR(NRF_PDM_EVENT_STARTED)); 80 81 uint8_t finished_buffer = m_cb.active_buffer; 82 83 // Check if the next buffer was set before. 84 uint8_t next_buffer = (~m_cb.active_buffer) & 0x01; 85 if (m_cb.buff_address[next_buffer] || 86 m_cb.op_state == NRFX_PDM_STATE_STARTING) 87 { 88 nrfx_pdm_evt_t evt; 89 evt.error = NRFX_PDM_NO_ERROR; 90 m_cb.error = 0; 91 92 // Release the full buffer if ready and request the next one. 93 if (m_cb.op_state == NRFX_PDM_STATE_STARTING) 94 { 95 evt.buffer_released = 0; 96 m_cb.op_state = NRFX_PDM_STATE_RUNNING; 97 } 98 else 99 { 100 evt.buffer_released = m_cb.buff_address[finished_buffer]; 101 m_cb.buff_address[finished_buffer] = 0; 102 m_cb.active_buffer = next_buffer; 103 } 104 evt.buffer_requested = true; 105 m_cb.event_handler(&evt); 106 } 107 else 108 { 109 // No next buffer available. Report an error. 110 // Do not request the new buffer as it was already done. 111 if (m_cb.error == 0) 112 { 113 nrfx_pdm_evt_t const evt = { 114 .buffer_requested = false, 115 .buffer_released = NULL, 116 .error = NRFX_PDM_ERROR_OVERFLOW 117 }; 118 m_cb.error = 1; 119 m_cb.event_handler(&evt); 120 } 121 } 122 123 if (m_cb.op_state == NRFX_PDM_STATE_STARTING) 124 { 125 m_cb.op_state = NRFX_PDM_STATE_RUNNING; 126 } 127 } 128 else if (nrf_pdm_event_check(NRF_PDM_EVENT_STOPPED)) 129 { 130 nrf_pdm_event_clear(NRF_PDM_EVENT_STOPPED); 131 NRFX_LOG_DEBUG("Event: %s.", EVT_TO_STR(NRF_PDM_EVENT_STOPPED)); 132 nrf_pdm_disable(); 133 m_cb.op_state = NRFX_PDM_STATE_IDLE; 134 135 // Release the buffers. 136 nrfx_pdm_evt_t evt; 137 evt.error = NRFX_PDM_NO_ERROR; 138 evt.buffer_requested = false; 139 if (m_cb.buff_address[m_cb.active_buffer]) 140 { 141 evt.buffer_released = m_cb.buff_address[m_cb.active_buffer]; 142 m_cb.buff_address[m_cb.active_buffer] = 0; 143 m_cb.event_handler(&evt); 144 } 145 146 uint8_t second_buffer = (~m_cb.active_buffer) & 0x01; 147 if (m_cb.buff_address[second_buffer]) 148 { 149 evt.buffer_released = m_cb.buff_address[second_buffer]; 150 m_cb.buff_address[second_buffer] = 0; 151 m_cb.event_handler(&evt); 152 } 153 m_cb.active_buffer = 0; 154 } 155 156 if (m_cb.irq_buff_request) 157 { 158 nrfx_pdm_evt_t const evt = 159 { 160 .buffer_requested = true, 161 .buffer_released = NULL, 162 .error = NRFX_PDM_NO_ERROR, 163 }; 164 m_cb.irq_buff_request = 0; 165 m_cb.event_handler(&evt); 166 } 167 } 168 169 170 nrfx_err_t nrfx_pdm_init(nrfx_pdm_config_t const * p_config, 171 nrfx_pdm_event_handler_t event_handler) 172 { 173 NRFX_ASSERT(p_config); 174 NRFX_ASSERT(event_handler); 175 nrfx_err_t err_code; 176 177 if (m_cb.drv_state != NRFX_DRV_STATE_UNINITIALIZED) 178 { 179 err_code = NRFX_ERROR_INVALID_STATE; 180 NRFX_LOG_WARNING("Function: %s, error code: %s.", 181 __func__, 182 NRFX_LOG_ERROR_STRING_GET(err_code)); 183 return err_code; 184 } 185 186 if (p_config->gain_l > NRF_PDM_GAIN_MAXIMUM || 187 p_config->gain_r > NRF_PDM_GAIN_MAXIMUM) 188 { 189 err_code = NRFX_ERROR_INVALID_PARAM; 190 NRFX_LOG_WARNING("Function: %s, error code: %s.", 191 __func__, 192 NRFX_LOG_ERROR_STRING_GET(err_code)); 193 return err_code; 194 } 195 196 m_cb.buff_address[0] = 0; 197 m_cb.buff_address[1] = 0; 198 m_cb.active_buffer = 0; 199 m_cb.error = 0; 200 m_cb.event_handler = event_handler; 201 m_cb.op_state = NRFX_PDM_STATE_IDLE; 202 203 nrf_pdm_clock_set(p_config->clock_freq); 204 nrf_pdm_mode_set(p_config->mode, p_config->edge); 205 nrf_pdm_gain_set(p_config->gain_l, p_config->gain_r); 206 207 nrf_gpio_cfg_output(p_config->pin_clk); 208 nrf_gpio_pin_clear(p_config->pin_clk); 209 nrf_gpio_cfg_input(p_config->pin_din, NRF_GPIO_PIN_NOPULL); 210 nrf_pdm_psel_connect(p_config->pin_clk, p_config->pin_din); 211 212 nrf_pdm_event_clear(NRF_PDM_EVENT_STARTED); 213 nrf_pdm_event_clear(NRF_PDM_EVENT_END); 214 nrf_pdm_event_clear(NRF_PDM_EVENT_STOPPED); 215 nrf_pdm_int_enable(NRF_PDM_INT_STARTED | NRF_PDM_INT_STOPPED); 216 NRFX_IRQ_PRIORITY_SET(PDM_IRQn, p_config->interrupt_priority); 217 NRFX_IRQ_ENABLE(PDM_IRQn); 218 m_cb.drv_state = NRFX_DRV_STATE_INITIALIZED; 219 220 err_code = NRFX_SUCCESS; 221 NRFX_LOG_INFO("Function: %s, error code: %s.", 222 __func__, 223 NRFX_LOG_ERROR_STRING_GET(err_code)); 224 return err_code; 225 } 226 227 void nrfx_pdm_uninit(void) 228 { 229 nrf_pdm_disable(); 230 nrf_pdm_psel_disconnect(); 231 m_cb.drv_state = NRFX_DRV_STATE_UNINITIALIZED; 232 NRFX_LOG_INFO("Uninitialized."); 233 } 234 235 static void pdm_start() 236 { 237 m_cb.drv_state = NRFX_DRV_STATE_POWERED_ON; 238 nrf_pdm_enable(); 239 nrf_pdm_event_clear(NRF_PDM_EVENT_STARTED); 240 nrf_pdm_task_trigger(NRF_PDM_TASK_START); 241 } 242 243 static void pdm_buf_request() 244 { 245 m_cb.irq_buff_request = 1; 246 NRFX_IRQ_PENDING_SET(PDM_IRQn); 247 } 248 249 nrfx_err_t nrfx_pdm_start(void) 250 { 251 NRFX_ASSERT(m_cb.drv_state != NRFX_DRV_STATE_UNINITIALIZED); 252 nrfx_err_t err_code; 253 254 if (m_cb.op_state != NRFX_PDM_STATE_IDLE) 255 { 256 if (m_cb.op_state == NRFX_PDM_STATE_RUNNING) 257 { 258 err_code = NRFX_SUCCESS; 259 NRFX_LOG_INFO("Function: %s, error code: %s.", 260 __func__, 261 NRFX_LOG_ERROR_STRING_GET(err_code)); 262 return err_code; 263 } 264 err_code = NRFX_ERROR_BUSY; 265 NRFX_LOG_WARNING("Function: %s, error code: %s.", 266 __func__, 267 NRFX_LOG_ERROR_STRING_GET(err_code)); 268 return err_code; 269 } 270 271 m_cb.op_state = NRFX_PDM_STATE_STARTING; 272 pdm_buf_request(); 273 274 err_code = NRFX_SUCCESS; 275 NRFX_LOG_INFO("Function: %s, error code: %s.", 276 __func__, 277 NRFX_LOG_ERROR_STRING_GET(err_code)); 278 return err_code; 279 } 280 281 nrfx_err_t nrfx_pdm_buffer_set(int16_t * buffer, uint16_t buffer_length) 282 { 283 if (m_cb.drv_state == NRFX_DRV_STATE_UNINITIALIZED) 284 { 285 return NRFX_ERROR_INVALID_STATE; 286 } 287 if (m_cb.op_state == NRFX_PDM_STATE_STOPPING) 288 { 289 return NRFX_ERROR_BUSY; 290 } 291 if ((buffer == NULL) || (buffer_length > NRFX_PDM_MAX_BUFFER_SIZE)) 292 { 293 return NRFX_ERROR_INVALID_PARAM; 294 } 295 296 nrfx_err_t err_code = NRFX_SUCCESS; 297 298 // Enter the PDM critical section. 299 NRFX_IRQ_DISABLE(PDM_IRQn); 300 301 uint8_t next_buffer = (~m_cb.active_buffer) & 0x01; 302 if (m_cb.op_state == NRFX_PDM_STATE_STARTING) 303 { 304 next_buffer = 0; 305 } 306 307 if (m_cb.buff_address[next_buffer]) 308 { 309 // Buffer already set. 310 err_code = NRFX_ERROR_BUSY; 311 } 312 else 313 { 314 m_cb.buff_address[next_buffer] = buffer; 315 m_cb.buff_length[next_buffer] = buffer_length; 316 nrf_pdm_buffer_set((uint32_t *)buffer, buffer_length); 317 318 if (m_cb.drv_state != NRFX_DRV_STATE_POWERED_ON) 319 { 320 pdm_start(); 321 } 322 } 323 324 NRFX_IRQ_ENABLE(PDM_IRQn); 325 return err_code; 326 } 327 328 nrfx_err_t nrfx_pdm_stop(void) 329 { 330 NRFX_ASSERT(m_cb.drv_state != NRFX_DRV_STATE_UNINITIALIZED); 331 nrfx_err_t err_code; 332 333 if (m_cb.op_state != NRFX_PDM_STATE_RUNNING) 334 { 335 if (m_cb.op_state == NRFX_PDM_STATE_IDLE || 336 m_cb.op_state == NRFX_PDM_STATE_STARTING) 337 { 338 nrf_pdm_disable(); 339 m_cb.op_state = NRFX_PDM_STATE_IDLE; 340 err_code = NRFX_SUCCESS; 341 NRFX_LOG_INFO("Function: %s, error code: %s.", 342 __func__, 343 NRFX_LOG_ERROR_STRING_GET(err_code)); 344 return err_code; 345 } 346 err_code = NRFX_ERROR_BUSY; 347 NRFX_LOG_WARNING("Function: %s, error code: %s.", 348 __func__, 349 NRFX_LOG_ERROR_STRING_GET(err_code)); 350 return err_code; 351 } 352 m_cb.drv_state = NRFX_DRV_STATE_INITIALIZED; 353 m_cb.op_state = NRFX_PDM_STATE_STOPPING; 354 355 nrf_pdm_task_trigger(NRF_PDM_TASK_STOP); 356 err_code = NRFX_SUCCESS; 357 NRFX_LOG_INFO("Function: %s, error code: %s.", __func__, NRFX_LOG_ERROR_STRING_GET(err_code)); 358 return err_code; 359 } 360 361 #endif // NRFX_CHECK(NRFX_PDM_ENABLED) 362