1 /*
2  * Copyright (c) 2016, 2017 Intel Corporation
3  * Copyright (c) 2017 IpTronix S.r.l.
4  * Copyright (c) 2021 Nordic Semiconductor ASA
5  *
6  * SPDX-License-Identifier: Apache-2.0
7  */
8 
9 /*
10  * Bus-specific functionality for BMP388s accessed via SPI.
11  */
12 
13 #include <zephyr/logging/log.h>
14 #include "bmp388.h"
15 
16 #if BMP388_BUS_SPI
17 
18 LOG_MODULE_DECLARE(BMP388, CONFIG_SENSOR_LOG_LEVEL);
19 
bmp388_bus_check_spi(const union bmp388_bus * bus)20 static int bmp388_bus_check_spi(const union bmp388_bus *bus)
21 {
22 	return spi_is_ready_dt(&bus->spi) ? 0 : -ENODEV;
23 }
24 
bmp388_reg_read_spi(const union bmp388_bus * bus,uint8_t start,uint8_t * buf,int size)25 static int bmp388_reg_read_spi(const union bmp388_bus *bus,
26 			       uint8_t start, uint8_t *buf, int size)
27 {
28 	uint8_t addr;
29 	const struct spi_buf tx_buf = {
30 		.buf = &addr,
31 		.len = 1
32 	};
33 	const struct spi_buf_set tx = {
34 		.buffers = &tx_buf,
35 		.count = 1
36 	};
37 	struct spi_buf rx_buf[2];
38 	const struct spi_buf_set rx = {
39 		.buffers = rx_buf,
40 		.count = ARRAY_SIZE(rx_buf)
41 	};
42 	int i;
43 
44 	rx_buf[0].buf = NULL;
45 	rx_buf[0].len = 1;
46 
47 	rx_buf[1].len = 1;
48 
49 	for (i = 0; i < size; i++) {
50 		int ret;
51 
52 		addr = (start + i) | 0x80;
53 		rx_buf[1].buf = &buf[i];
54 
55 		ret = spi_transceive_dt(&bus->spi, &tx, &rx);
56 		if (ret) {
57 			LOG_DBG("spi_transceive FAIL %d\n", ret);
58 			return ret;
59 		}
60 	}
61 
62 	return 0;
63 }
64 
bmp388_reg_write_spi(const union bmp388_bus * bus,uint8_t reg,uint8_t val)65 static int bmp388_reg_write_spi(const union bmp388_bus *bus,
66 				uint8_t reg, uint8_t val)
67 {
68 	uint8_t cmd[] = { reg & 0x7F, val };
69 	const struct spi_buf tx_buf = {
70 		.buf = cmd,
71 		.len = sizeof(cmd)
72 	};
73 	const struct spi_buf_set tx = {
74 		.buffers = &tx_buf,
75 		.count = 1
76 	};
77 	int ret;
78 
79 	ret = spi_write_dt(&bus->spi, &tx);
80 	if (ret) {
81 		LOG_DBG("spi_write FAIL %d\n", ret);
82 		return ret;
83 	}
84 	return 0;
85 }
86 
87 const struct bmp388_bus_io bmp388_bus_io_spi = {
88 	.check = bmp388_bus_check_spi,
89 	.read = bmp388_reg_read_spi,
90 	.write = bmp388_reg_write_spi,
91 };
92 #endif /* BMP388_BUS_SPI */
93