1 |
|
---|
2 | /** \addtogroup hal */
|
---|
3 | /** @{*/
|
---|
4 | /* mbed Microcontroller Library
|
---|
5 | * Copyright (c) 2006-2013 ARM Limited
|
---|
6 | *
|
---|
7 | * Licensed under the Apache License, Version 2.0 (the "License");
|
---|
8 | * you may not use this file except in compliance with the License.
|
---|
9 | * You may obtain a copy of the License at
|
---|
10 | *
|
---|
11 | * http://www.apache.org/licenses/LICENSE-2.0
|
---|
12 | *
|
---|
13 | * Unless required by applicable law or agreed to in writing, software
|
---|
14 | * distributed under the License is distributed on an "AS IS" BASIS,
|
---|
15 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
---|
16 | * See the License for the specific language governing permissions and
|
---|
17 | * limitations under the License.
|
---|
18 | */
|
---|
19 | #ifndef MBED_SPI_API_H
|
---|
20 | #define MBED_SPI_API_H
|
---|
21 |
|
---|
22 | #include "device.h"
|
---|
23 | #include "hal/dma_api.h"
|
---|
24 | #include "hal/buffer.h"
|
---|
25 |
|
---|
26 | #if DEVICE_SPI
|
---|
27 |
|
---|
28 | #define SPI_EVENT_ERROR (1 << 1)
|
---|
29 | #define SPI_EVENT_COMPLETE (1 << 2)
|
---|
30 | #define SPI_EVENT_RX_OVERFLOW (1 << 3)
|
---|
31 | #define SPI_EVENT_ALL (SPI_EVENT_ERROR | SPI_EVENT_COMPLETE | SPI_EVENT_RX_OVERFLOW)
|
---|
32 |
|
---|
33 | #define SPI_EVENT_INTERNAL_TRANSFER_COMPLETE (1 << 30) // Internal flag to report that an event occurred
|
---|
34 |
|
---|
35 | #define SPI_FILL_WORD (0xFFFF)
|
---|
36 | #define SPI_FILL_CHAR (0xFF)
|
---|
37 |
|
---|
38 | #if DEVICE_SPI_ASYNCH
|
---|
39 | /** Asynch SPI HAL structure
|
---|
40 | */
|
---|
41 | typedef struct {
|
---|
42 | struct spi_s spi; /**< Target specific SPI structure */
|
---|
43 | struct buffer_s tx_buff; /**< Tx buffer */
|
---|
44 | struct buffer_s rx_buff; /**< Rx buffer */
|
---|
45 | } spi_t;
|
---|
46 |
|
---|
47 | #else
|
---|
48 | /** Non-asynch SPI HAL structure
|
---|
49 | */
|
---|
50 | typedef struct spi_s spi_t;
|
---|
51 |
|
---|
52 | #endif
|
---|
53 |
|
---|
54 | #ifdef __cplusplus
|
---|
55 | extern "C" {
|
---|
56 | #endif
|
---|
57 |
|
---|
58 | /**
|
---|
59 | * \defgroup hal_GeneralSPI SPI Configuration Functions
|
---|
60 | * @{
|
---|
61 | */
|
---|
62 |
|
---|
63 | /** Initialize the SPI peripheral
|
---|
64 | *
|
---|
65 | * Configures the pins used by SPI, sets a default format and frequency, and enables the peripheral
|
---|
66 | * @param[out] obj The SPI object to initialize
|
---|
67 | * @param[in] mosi The pin to use for MOSI
|
---|
68 | * @param[in] miso The pin to use for MISO
|
---|
69 | * @param[in] sclk The pin to use for SCLK
|
---|
70 | * @param[in] ssel The pin to use for SSEL
|
---|
71 | */
|
---|
72 | void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel);
|
---|
73 |
|
---|
74 | /** Release a SPI object
|
---|
75 | *
|
---|
76 | * TODO: spi_free is currently unimplemented
|
---|
77 | * This will require reference counting at the C++ level to be safe
|
---|
78 | *
|
---|
79 | * Return the pins owned by the SPI object to their reset state
|
---|
80 | * Disable the SPI peripheral
|
---|
81 | * Disable the SPI clock
|
---|
82 | * @param[in] obj The SPI object to deinitialize
|
---|
83 | */
|
---|
84 | void spi_free(spi_t *obj);
|
---|
85 |
|
---|
86 | /** Configure the SPI format
|
---|
87 | *
|
---|
88 | * Set the number of bits per frame, configure clock polarity and phase, shift order and master/slave mode.
|
---|
89 | * The default bit order is MSB.
|
---|
90 | * @param[in,out] obj The SPI object to configure
|
---|
91 | * @param[in] bits The number of bits per frame
|
---|
92 | * @param[in] mode The SPI mode (clock polarity, phase, and shift direction)
|
---|
93 | * @param[in] slave Zero for master mode or non-zero for slave mode
|
---|
94 | */
|
---|
95 | void spi_format(spi_t *obj, int bits, int mode, int slave);
|
---|
96 |
|
---|
97 | /** Set the SPI baud rate
|
---|
98 | *
|
---|
99 | * Actual frequency may differ from the desired frequency due to available dividers and bus clock
|
---|
100 | * Configures the SPI peripheral's baud rate
|
---|
101 | * @param[in,out] obj The SPI object to configure
|
---|
102 | * @param[in] hz The baud rate in Hz
|
---|
103 | */
|
---|
104 | void spi_frequency(spi_t *obj, int hz);
|
---|
105 |
|
---|
106 | /**@}*/
|
---|
107 | /**
|
---|
108 | * \defgroup SynchSPI Synchronous SPI Hardware Abstraction Layer
|
---|
109 | * @{
|
---|
110 | */
|
---|
111 |
|
---|
112 | /** Write a byte out in master mode and receive a value
|
---|
113 | *
|
---|
114 | * @param[in] obj The SPI peripheral to use for sending
|
---|
115 | * @param[in] value The value to send
|
---|
116 | * @return Returns the value received during send
|
---|
117 | */
|
---|
118 | int spi_master_write(spi_t *obj, int value);
|
---|
119 |
|
---|
120 | /** Write a block out in master mode and receive a value
|
---|
121 | *
|
---|
122 | * The total number of bytes sent and received will be the maximum of
|
---|
123 | * tx_length and rx_length. The bytes written will be padded with the
|
---|
124 | * value 0xff.
|
---|
125 | *
|
---|
126 | * @param[in] obj The SPI peripheral to use for sending
|
---|
127 | * @param[in] tx_buffer Pointer to the byte-array of data to write to the device
|
---|
128 | * @param[in] tx_length Number of bytes to write, may be zero
|
---|
129 | * @param[in] rx_buffer Pointer to the byte-array of data to read from the device
|
---|
130 | * @param[in] rx_length Number of bytes to read, may be zero
|
---|
131 | * @param[in] write_fill Default data transmitted while performing a read
|
---|
132 | * @returns
|
---|
133 | * The number of bytes written and read from the device. This is
|
---|
134 | * maximum of tx_length and rx_length.
|
---|
135 | */
|
---|
136 | int spi_master_block_write(spi_t *obj, const char *tx_buffer, int tx_length, char *rx_buffer, int rx_length, char write_fill);
|
---|
137 |
|
---|
138 | /** Check if a value is available to read
|
---|
139 | *
|
---|
140 | * @param[in] obj The SPI peripheral to check
|
---|
141 | * @return non-zero if a value is available
|
---|
142 | */
|
---|
143 | int spi_slave_receive(spi_t *obj);
|
---|
144 |
|
---|
145 | /** Get a received value out of the SPI receive buffer in slave mode
|
---|
146 | *
|
---|
147 | * Blocks until a value is available
|
---|
148 | * @param[in] obj The SPI peripheral to read
|
---|
149 | * @return The value received
|
---|
150 | */
|
---|
151 | int spi_slave_read(spi_t *obj);
|
---|
152 |
|
---|
153 | /** Write a value to the SPI peripheral in slave mode
|
---|
154 | *
|
---|
155 | * Blocks until the SPI peripheral can be written to
|
---|
156 | * @param[in] obj The SPI peripheral to write
|
---|
157 | * @param[in] value The value to write
|
---|
158 | */
|
---|
159 | void spi_slave_write(spi_t *obj, int value);
|
---|
160 |
|
---|
161 | /** Checks if the specified SPI peripheral is in use
|
---|
162 | *
|
---|
163 | * @param[in] obj The SPI peripheral to check
|
---|
164 | * @return non-zero if the peripheral is currently transmitting
|
---|
165 | */
|
---|
166 | int spi_busy(spi_t *obj);
|
---|
167 |
|
---|
168 | /** Get the module number
|
---|
169 | *
|
---|
170 | * @param[in] obj The SPI peripheral to check
|
---|
171 | * @return The module number
|
---|
172 | */
|
---|
173 | uint8_t spi_get_module(spi_t *obj);
|
---|
174 |
|
---|
175 | /**@}*/
|
---|
176 |
|
---|
177 | #if DEVICE_SPI_ASYNCH
|
---|
178 | /**
|
---|
179 | * \defgroup AsynchSPI Asynchronous SPI Hardware Abstraction Layer
|
---|
180 | * @{
|
---|
181 | */
|
---|
182 |
|
---|
183 | /** Begin the SPI transfer. Buffer pointers and lengths are specified in tx_buff and rx_buff
|
---|
184 | *
|
---|
185 | * @param[in] obj The SPI object that holds the transfer information
|
---|
186 | * @param[in] tx The transmit buffer
|
---|
187 | * @param[in] tx_length The number of bytes to transmit
|
---|
188 | * @param[in] rx The receive buffer
|
---|
189 | * @param[in] rx_length The number of bytes to receive
|
---|
190 | * @param[in] bit_width The bit width of buffer words
|
---|
191 | * @param[in] event The logical OR of events to be registered
|
---|
192 | * @param[in] handler SPI interrupt handler
|
---|
193 | * @param[in] hint A suggestion for how to use DMA with this transfer
|
---|
194 | */
|
---|
195 | void spi_master_transfer(spi_t *obj, const void *tx, size_t tx_length, void *rx, size_t rx_length, uint8_t bit_width, uint32_t handler, uint32_t event, DMAUsage hint);
|
---|
196 |
|
---|
197 | /** The asynchronous IRQ handler
|
---|
198 | *
|
---|
199 | * Reads the received values out of the RX FIFO, writes values into the TX FIFO and checks for transfer termination
|
---|
200 | * conditions, such as buffer overflows or transfer complete.
|
---|
201 | * @param[in] obj The SPI object that holds the transfer information
|
---|
202 | * @return Event flags if a transfer termination condition was met; otherwise 0.
|
---|
203 | */
|
---|
204 | uint32_t spi_irq_handler_asynch(spi_t *obj);
|
---|
205 |
|
---|
206 | /** Attempts to determine if the SPI peripheral is already in use
|
---|
207 | *
|
---|
208 | * If a temporary DMA channel has been allocated, peripheral is in use.
|
---|
209 | * If a permanent DMA channel has been allocated, check if the DMA channel is in use. If not, proceed as though no DMA
|
---|
210 | * channel were allocated.
|
---|
211 | * If no DMA channel is allocated, check whether tx and rx buffers have been assigned. For each assigned buffer, check
|
---|
212 | * if the corresponding buffer position is less than the buffer length. If buffers do not indicate activity, check if
|
---|
213 | * there are any bytes in the FIFOs.
|
---|
214 | * @param[in] obj The SPI object to check for activity
|
---|
215 | * @return Non-zero if the SPI port is active or zero if it is not.
|
---|
216 | */
|
---|
217 | uint8_t spi_active(spi_t *obj);
|
---|
218 |
|
---|
219 | /** Abort an SPI transfer
|
---|
220 | *
|
---|
221 | * @param obj The SPI peripheral to stop
|
---|
222 | */
|
---|
223 | void spi_abort_asynch(spi_t *obj);
|
---|
224 |
|
---|
225 |
|
---|
226 | #endif
|
---|
227 |
|
---|
228 | /**@}*/
|
---|
229 |
|
---|
230 | #ifdef __cplusplus
|
---|
231 | }
|
---|
232 | #endif // __cplusplus
|
---|
233 |
|
---|
234 | #endif // SPI_DEVICE
|
---|
235 |
|
---|
236 | #endif // MBED_SPI_API_H
|
---|
237 |
|
---|
238 | /** @}*/
|
---|