1 /*
2 * Copyright (c) 2022 Würth Elektronik eiSos GmbH & Co. KG
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include "weplatform_spi.h"
8
9 #include <errno.h>
10
11 #ifdef CONFIG_SPI
12 #include <zephyr/drivers/spi.h>
13 #endif /* CONFIG_SPI */
14
15 /**
16 * @brief Read data starting from the addressed register via SPI
17 * @param[in] interface Sensor interface
18 * @param[in] regAdr The register address to read from
19 * @param[in] numBytesToRead Number of bytes to read
20 * @param[out] data The read data will be stored here
21 * @retval Error code
22 */
WE_ReadReg_SPI(WE_sensorInterface_t * interface,uint8_t regAdr,uint16_t numBytesToRead,uint8_t * data)23 inline int8_t WE_ReadReg_SPI(WE_sensorInterface_t *interface, uint8_t regAdr,
24 uint16_t numBytesToRead, uint8_t *data)
25 {
26 int status = 0;
27
28 #ifdef CONFIG_SPI
29 uint8_t bytesStep = interface->options.spi.burstMode ? numBytesToRead : 1;
30
31 for (uint8_t i = 0; i < numBytesToRead; i += bytesStep) {
32 uint8_t buffer_tx[2] = { (regAdr + i) | (1 << 7), 0 };
33
34 /* Write 1 byte containing register address (MSB=1) + 1 dummy byte */
35 const struct spi_buf tx_buf = { .buf = buffer_tx, .len = 2 };
36 const struct spi_buf_set tx_buf_set = { .buffers = &tx_buf, .count = 1 };
37
38 /* Skip first byte, then read "bytesStep" bytes of data */
39 const struct spi_buf rx_buf[2] = { { .buf = NULL, .len = 1 },
40 { .buf = data + i, .len = bytesStep } };
41 const struct spi_buf_set rx_buf_set = { .buffers = rx_buf, .count = 2 };
42
43 status = spi_transceive_dt(interface->handle, &tx_buf_set, &rx_buf_set);
44 if (status != 0) {
45 /* Error, abort */
46 break;
47 }
48 }
49 #else
50 status = -EIO;
51 #endif /* CONFIG_SPI */
52
53 return status == 0 ? WE_SUCCESS : WE_FAIL;
54 }
55
56 /**
57 * @brief Write data starting from the addressed register via SPI
58 * @param[in] interface Sensor interface
59 * @param[in] regAdr Address of register to be written
60 * @param[in] numBytesToWrite Number of bytes to write
61 * @param[in] data Data to be written
62 * @retval Error code
63 */
WE_WriteReg_SPI(WE_sensorInterface_t * interface,uint8_t regAdr,uint16_t numBytesToWrite,uint8_t * data)64 inline int8_t WE_WriteReg_SPI(WE_sensorInterface_t *interface, uint8_t regAdr,
65 uint16_t numBytesToWrite, uint8_t *data)
66 {
67 int status = 0;
68
69 #ifdef CONFIG_SPI
70 uint8_t bytesStep = interface->options.spi.burstMode ? numBytesToWrite : 1;
71
72 for (uint8_t i = 0; i < numBytesToWrite; i += bytesStep) {
73 uint8_t buffer_tx[1] = { (regAdr + i) & ~(1 << 7) };
74
75 /*
76 * First write 1 byte containing register address (MSB=0), then
77 * write "bytesStep" bytes of data
78 */
79 const struct spi_buf tx_buf[2] = { { .buf = buffer_tx, .len = 1 },
80 { .buf = data + i, .len = bytesStep } };
81 const struct spi_buf_set tx_buf_set = { .buffers = tx_buf, .count = 2 };
82
83 status = spi_write_dt(interface->handle, &tx_buf_set);
84
85 if (status != 0) {
86 /* Error, abort */
87 break;
88 }
89 }
90 #else
91 status = -EIO;
92 #endif /* CONFIG_SPI */
93
94 return status == 0 ? WE_SUCCESS : WE_FAIL;
95 }
96
