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 #ifndef NRFX_TWIS_H__
33 #define NRFX_TWIS_H__
34
35 #include <nrfx.h>
36 #include <hal/nrf_twis.h>
37 #include <hal/nrf_gpio.h>
38
39 #ifdef __cplusplus
40 extern "C" {
41 #endif
42
43 /**
44 * @defgroup nrfx_twis TWIS driver
45 * @{
46 * @ingroup nrf_twis
47 * @brief Two Wire Slave interface (TWIS) peripheral driver.
48 */
49
50 /**
51 * @brief TWIS driver instance data structure.
52 */
53 typedef struct
54 {
55 NRF_TWIS_Type * p_reg; ///< Pointer to a structure with TWIS registers.
56 uint8_t drv_inst_idx; ///< Driver instance index.
57 } nrfx_twis_t;
58
59 enum {
60 #if NRFX_CHECK(NRFX_TWIS0_ENABLED)
61 NRFX_TWIS0_INST_IDX,
62 #endif
63 #if NRFX_CHECK(NRFX_TWIS1_ENABLED)
64 NRFX_TWIS1_INST_IDX,
65 #endif
66 #if NRFX_CHECK(NRFX_TWIS2_ENABLED)
67 NRFX_TWIS2_INST_IDX,
68 #endif
69 #if NRFX_CHECK(NRFX_TWIS3_ENABLED)
70 NRFX_TWIS3_INST_IDX,
71 #endif
72 NRFX_TWIS_ENABLED_COUNT
73 };
74
75 /**
76 * @brief Macro for creating a TWIS driver instance.
77 */
78 #define NRFX_TWIS_INSTANCE(id) \
79 { \
80 .p_reg = NRFX_CONCAT_2(NRF_TWIS, id), \
81 .drv_inst_idx = NRFX_CONCAT_3(NRFX_TWIS, id, _INST_IDX), \
82 }
83
84 /**
85 * @brief Event callback function event definitions.
86 */
87 typedef enum
88 {
89 NRFX_TWIS_EVT_READ_REQ, ///< Read request detected.
90 /**< If there is no buffer prepared, buf_req flag in the even will be set.
91 Call then @ref nrfx_twis_tx_prepare to give parameters for buffer.
92 */
93 NRFX_TWIS_EVT_READ_DONE, ///< Read request has finished - free any data.
94 NRFX_TWIS_EVT_READ_ERROR, ///< Read request finished with error.
95 NRFX_TWIS_EVT_WRITE_REQ, ///< Write request detected.
96 /**< If there is no buffer prepared, buf_req flag in the even will be set.
97 Call then @ref nrfx_twis_rx_prepare to give parameters for buffer.
98 */
99 NRFX_TWIS_EVT_WRITE_DONE, ///< Write request has finished - process data.
100 NRFX_TWIS_EVT_WRITE_ERROR, ///< Write request finished with error.
101 NRFX_TWIS_EVT_GENERAL_ERROR ///< Error that happens not inside WRITE or READ transaction.
102 } nrfx_twis_evt_type_t;
103
104 /**
105 * @brief Possible error sources.
106 *
107 * This is flag enum - values from this enum can be connected using logical or operator.
108 * @note
109 * We could use directly @ref nrf_twis_error_t. Error type enum is redefined here because
110 * of possible future extension (eg. supporting timeouts and synchronous mode).
111 */
112 typedef enum
113 {
114 NRFX_TWIS_ERROR_OVERFLOW = NRF_TWIS_ERROR_OVERFLOW, /**< RX buffer overflow detected, and prevented. */
115 NRFX_TWIS_ERROR_DATA_NACK = NRF_TWIS_ERROR_DATA_NACK, /**< NACK sent after receiving a data byte. */
116 NRFX_TWIS_ERROR_OVERREAD = NRF_TWIS_ERROR_OVERREAD, /**< TX buffer over-read detected, and prevented. */
117 NRFX_TWIS_ERROR_UNEXPECTED_EVENT = 1 << 8 /**< Unexpected event detected by state machine. */
118 } nrfx_twis_error_t;
119
120 /**
121 * @brief TWIS driver event structure.
122 */
123 typedef struct
124 {
125 nrfx_twis_evt_type_t type; ///< Event type.
126 union
127 {
128 bool buf_req; ///< Flag for @ref NRFX_TWIS_EVT_READ_REQ and @ref NRFX_TWIS_EVT_WRITE_REQ.
129 /**< Information if transmission buffer requires to be prepared. */
130 uint32_t tx_amount; ///< Data for @ref NRFX_TWIS_EVT_READ_DONE.
131 uint32_t rx_amount; ///< Data for @ref NRFX_TWIS_EVT_WRITE_DONE.
132 uint32_t error; ///< Data for @ref NRFX_TWIS_EVT_GENERAL_ERROR.
133 } data;
134 } nrfx_twis_evt_t;
135
136 /**
137 * @brief TWI slave event callback function type.
138 *
139 * @param[in] p_event Event information structure.
140 */
141 typedef void (*nrfx_twis_event_handler_t)(nrfx_twis_evt_t const * p_event);
142
143 /**
144 * @brief Structure for TWIS configuration.
145 */
146 typedef struct
147 {
148 uint32_t addr[2]; //!< Set addresses that this slave should respond. Set 0 to disable.
149 uint32_t scl; //!< SCL pin number.
150 uint32_t sda; //!< SDA pin number.
151 nrf_gpio_pin_pull_t scl_pull; //!< SCL pin pull.
152 nrf_gpio_pin_pull_t sda_pull; //!< SDA pin pull.
153 uint8_t interrupt_priority; //!< The priority of interrupt for the module to set.
154 } nrfx_twis_config_t;
155
156 /**
157 * @brief Generate default configuration for TWIS driver instance.
158 */
159 #define NRFX_TWIS_DEFAULT_CONFIG \
160 { \
161 .addr = { NRFX_TWIS_DEFAULT_CONFIG_ADDR0, \
162 NRFX_TWIS_DEFAULT_CONFIG_ADDR1 }, \
163 .scl = 31, \
164 .scl_pull = (nrf_gpio_pin_pull_t)NRFX_TWIS_DEFAULT_CONFIG_SCL_PULL, \
165 .sda = 31, \
166 .sda_pull = (nrf_gpio_pin_pull_t)NRFX_TWIS_DEFAULT_CONFIG_SDA_PULL, \
167 .interrupt_priority = NRFX_TWIS_DEFAULT_CONFIG_IRQ_PRIORITY \
168 }
169
170 /**
171 * @brief Function for initializing the TWIS driver instance.
172 *
173 * Function initializes and enables TWIS driver.
174 * @attention After driver initialization enable it by @ref nrfx_twis_enable.
175 *
176 * @param[in] p_instance Pointer to the driver instance structure.
177 * @attention @em p_instance has to be global object.
178 * It would be used by interrupts so make it sure that object
179 * would not be destroyed when function is leaving.
180 * @param[in] p_config Pointer to the structure with initial configuration.
181 * @param[in] event_handler Event handler provided by the user.
182 *
183 * @retval NRFX_SUCCESS If initialization was successful.
184 * @retval NRFX_ERROR_INVALID_STATE If the driver is already initialized.
185 * @retval NRFX_ERROR_BUSY If some other peripheral with the same
186 * instance ID is already in use. This is
187 * possible only if NRFX_PRS_ENABLED
188 * is set to a value other than zero.
189 */
190 nrfx_err_t nrfx_twis_init(nrfx_twis_t const * p_instance,
191 nrfx_twis_config_t const * p_config,
192 nrfx_twis_event_handler_t event_handler);
193
194 /**
195 * @brief Function for uninitializing the TWIS driver instance.
196 *
197 * Function initializes the peripheral and resets all registers to default values.
198 *
199 * @param[in] p_instance Pointer to the driver instance structure.
200 * @note
201 * It is safe to call nrfx_twis_uninit even before initialization.
202 * Actually @ref nrfx_twis_init function calls this function to
203 * make sure that TWIS state is known.
204 * @note
205 * If TWIS driver was in uninitialized state before calling this function,
206 * selected pins would not be reset to default configuration.
207 */
208 void nrfx_twis_uninit(nrfx_twis_t const * p_instance);
209
210 /**
211 * @brief Enable TWIS instance.
212 *
213 * This function enables TWIS instance.
214 * Function defined if there is needs for dynamically enabling and disabling the peripheral.
215 * Use @ref nrfx_twis_enable and @ref nrfx_twis_disable functions.
216 * They do not change any configuration registers.
217 *
218 * @param p_instance Pointer to the driver instance structure.
219 */
220 void nrfx_twis_enable(nrfx_twis_t const * p_instance);
221
222 /**
223 * @brief Disable TWIS instance.
224 *
225 * Disabling TWIS instance gives possibility to turn off the TWIS while
226 * holding configuration done by @ref nrfx_twis_init.
227 *
228 * @param p_instance Pointer to the driver instance structure.
229 */
230 void nrfx_twis_disable(nrfx_twis_t const * p_instance);
231
232 /**
233 * @brief Get and clear last error flags.
234 *
235 * Function gets information about errors.
236 * This is also the only possibility to exit from error substate of the internal state machine.
237 *
238 * @param[in] p_instance Pointer to the driver instance structure.
239 * @return Error flags defined in @ref nrfx_twis_error_t.
240 * @attention
241 * This function clears error state and flags.
242 */
243 uint32_t nrfx_twis_error_get_and_clear(nrfx_twis_t const * p_instance);
244
245
246 /**
247 * @brief Prepare data for sending.
248 *
249 * This function should be used in response for @ref NRFX_TWIS_EVT_READ_REQ event.
250 *
251 * @note Peripherals using EasyDMA (including TWIS) require the transfer buffers
252 * to be placed in the Data RAM region. If this condition is not met,
253 * this function will fail with the error code NRFX_ERROR_INVALID_ADDR.
254 *
255 * @param[in] p_instance Pointer to the driver instance structure.
256 * @param[in] p_buf Transmission buffer.
257 * @attention Transmission buffer has to be placed in RAM.
258 * @param size Maximum number of bytes that master may read from buffer given.
259 *
260 * @retval NRFX_SUCCESS Preparation finished properly.
261 * @retval NRFX_ERROR_INVALID_ADDR Given @em p_buf is not placed inside the RAM.
262 * @retval NRFX_ERROR_INVALID_LENGTH Wrong value in @em size parameter.
263 * @retval NRFX_ERROR_INVALID_STATE Module not initialized or not enabled.
264 */
265 nrfx_err_t nrfx_twis_tx_prepare(nrfx_twis_t const * p_instance,
266 void const * p_buf,
267 size_t size);
268
269 /**
270 * @brief Get number of transmitted bytes.
271 *
272 * Function returns number of bytes sent.
273 * This function may be called after @ref NRFX_TWIS_EVT_READ_DONE or @ref NRFX_TWIS_EVT_READ_ERROR events.
274 *
275 * @param[in] p_instance Pointer to the driver instance structure.
276 *
277 * @return Number of bytes sent.
278 */
279 __STATIC_INLINE size_t nrfx_twis_tx_amount(nrfx_twis_t const * p_instance);
280
281 /**
282 * @brief Prepare data for receiving
283 *
284 * This function should be used in response for @ref NRFX_TWIS_EVT_WRITE_REQ event.
285 *
286 * @note Peripherals using EasyDMA (including TWIS) require the transfer buffers
287 * to be placed in the Data RAM region. If this condition is not met,
288 * this function will fail with the error code NRFX_ERROR_INVALID_ADDR.
289 *
290 * @param[in] p_instance Pointer to the driver instance structure.
291 * @param[in] p_buf Buffer that would be filled with received data.
292 * @attention Receiving buffer has to be placed in RAM.
293 * @param size Size of the buffer (maximum amount of data to receive).
294 *
295 * @retval NRFX_SUCCESS Preparation finished properly.
296 * @retval NRFX_ERROR_INVALID_ADDR Given @em p_buf is not placed inside the RAM.
297 * @retval NRFX_ERROR_INVALID_LENGTH Wrong value in @em size parameter.
298 * @retval NRFX_ERROR_INVALID_STATE Module not initialized or not enabled.
299 */
300 nrfx_err_t nrfx_twis_rx_prepare(nrfx_twis_t const * p_instance,
301 void * p_buf,
302 size_t size);
303
304 /**
305 * @brief Get number of received bytes.
306 *
307 * Function returns number of bytes received.
308 * This function may be called after @ref NRFX_TWIS_EVT_WRITE_DONE or @ref NRFX_TWIS_EVT_WRITE_ERROR events.
309 *
310 * @param[in] p_instance Pointer to the driver instance structure.
311 *
312 * @return Number of bytes received.
313 */
314 __STATIC_INLINE size_t nrfx_twis_rx_amount(nrfx_twis_t const * p_instance);
315
316 /**
317 * @brief Function checks if driver is busy right now.
318 *
319 * Actual driver substate is tested.
320 * If driver is in any other state than IDLE or ERROR this function returns true.
321 *
322 * @param[in] p_instance Pointer to the driver instance structure.
323 *
324 * @retval true Driver is in state other than ERROR or IDLE.
325 * @retval false There is no transmission pending.
326 */
327 bool nrfx_twis_is_busy(nrfx_twis_t const * p_instance);
328
329 /**
330 * @brief Function checks if driver is waiting for tx buffer.
331 *
332 * If this function returns true, it means that driver is stalled expecting
333 * of the @ref nrfx_twis_tx_prepare function call.
334 *
335 * @param[in] p_instance Pointer to the driver instance structure.
336 *
337 * @retval true Driver waits for @ref nrfx_twis_tx_prepare.
338 * @retval false Driver is not in the state where it waits for preparing tx buffer.
339 */
340 bool nrfx_twis_is_waiting_tx_buff(nrfx_twis_t const * p_instance);
341
342 /**
343 * @brief Function checks if driver is waiting for rx buffer.
344 *
345 * If this function returns true, it means that driver is staled expecting
346 * of the @ref nrfx_twis_rx_prepare function call.
347 *
348 * @param[in] p_instance Pointer to the driver instance structure.
349 *
350 * @retval true Driver waits for @ref nrfx_twis_rx_prepare.
351 * @retval false Driver is not in the state where it waits for preparing rx buffer.
352 */
353 bool nrfx_twis_is_waiting_rx_buff(nrfx_twis_t const * p_instance);
354
355 /**
356 * @brief Check if driver is sending data.
357 *
358 * If this function returns true, it means that there is ongoing output transmission.
359 *
360 * @param[in] p_instance Pointer to the driver instance structure.
361 *
362 * @retval true There is ongoing output transmission.
363 * @retval false Driver is in other state.
364 */
365 bool nrfx_twis_is_pending_tx(nrfx_twis_t const * p_instance);
366
367 /**
368 * @brief Check if driver is receiving data.
369 *
370 * If this function returns true, it means that there is ongoing input transmission.
371 *
372 * @param[in] p_instance Pointer to the driver instance structure.
373 *
374 * @retval true There is ongoing input transmission.
375 * @retval false Driver is in other state.
376 */
377 bool nrfx_twis_is_pending_rx(nrfx_twis_t const * p_instance);
378
379 #ifndef SUPPRESS_INLINE_IMPLEMENTATION
nrfx_twis_tx_amount(nrfx_twis_t const * p_instance)380 __STATIC_INLINE size_t nrfx_twis_tx_amount(nrfx_twis_t const * p_instance)
381 {
382 return nrf_twis_tx_amount_get(p_instance->p_reg);
383 }
384
nrfx_twis_rx_amount(nrfx_twis_t const * p_instance)385 __STATIC_INLINE size_t nrfx_twis_rx_amount(nrfx_twis_t const * p_instance)
386 {
387 return nrf_twis_rx_amount_get(p_instance->p_reg);
388 }
389 #endif // SUPPRESS_INLINE_IMPLEMENTATION
390
391
392 void nrfx_twis_0_irq_handler(void);
393 void nrfx_twis_1_irq_handler(void);
394 void nrfx_twis_2_irq_handler(void);
395 void nrfx_twis_3_irq_handler(void);
396
397
398 /** @} */
399
400 #ifdef __cplusplus
401 }
402 #endif
403
404 #endif // NRFX_TWIS_H__
405