zephyr/drivers/sensor/bme680/bme680_spi.c

147 lines
2.9 KiB
C

/*
* Copyright (c) 2016, 2017 Intel Corporation
* Copyright (c) 2017 IpTronix S.r.l.
* Copyright (c) 2021 Nordic Semiconductor ASA
* Copyright (c) 2022, Leonard Pollak
*
* SPDX-License-Identifier: Apache-2.0
*/
/*
* Bus-specific functionality for BME680s accessed via SPI.
*/
#include <zephyr/logging/log.h>
#include "bme680.h"
#if BME680_BUS_SPI
LOG_MODULE_DECLARE(bme680, CONFIG_SENSOR_LOG_LEVEL);
static int bme680_bus_check_spi(const union bme680_bus *bus)
{
return spi_is_ready(&bus->spi) ? 0 : -ENODEV;
}
static inline int bme680_set_mem_page(const struct device *dev, uint8_t addr)
{
const struct bme680_config *config = dev->config;
struct bme680_data *data = dev->data;
uint8_t page = (addr > 0x7f) ? 0U : 1U;
int err = 0;
if (data->mem_page != page) {
uint8_t buf[2];
struct spi_buf tx_buf = {
.buf = &buf[0],
.len = 1,
};
const struct spi_buf_set tx = {
.buffers = &tx_buf,
.count = 1,
};
const struct spi_buf rx_buf[] = {
{ .buf = NULL, .len = 1 },
{ .buf = &buf[1], .len = 1 },
};
const struct spi_buf_set rx = {
.buffers = rx_buf,
.count = ARRAY_SIZE(rx_buf),
};
buf[0] = BME680_REG_STATUS | BME680_SPI_READ_BIT;
err = spi_transceive_dt(&config->bus.spi, &tx, &rx);
if (err < 0) {
return err;
}
if (data->mem_page == 1U) {
buf[1] &= ~BME680_SPI_MEM_PAGE_MSK;
} else {
buf[1] |= BME680_SPI_MEM_PAGE_MSK;
}
buf[0] = BME680_REG_STATUS & BME680_SPI_WRITE_MSK;
tx_buf.len = 2;
err = spi_write_dt(&config->bus.spi, &tx);
if (err < 0) {
return err;
}
data->mem_page = page;
}
return err;
}
static int bme680_reg_write_spi(const struct device *dev,
uint8_t reg, uint8_t val)
{
const struct bme680_config *config = dev->config;
int err;
uint8_t cmd[] = { reg & BME680_SPI_WRITE_MSK, val };
const struct spi_buf tx_buf = {
.buf = cmd,
.len = sizeof(cmd)
};
const struct spi_buf_set tx = {
.buffers = &tx_buf,
.count = 1
};
err = bme680_set_mem_page(dev, reg);
if (err) {
return err;
}
err = spi_write_dt(&config->bus.spi, &tx);
return err;
}
static int bme680_reg_read_spi(const struct device *dev,
uint8_t start, uint8_t *buf, int size)
{
const struct bme680_config *config = dev->config;
int err;
uint8_t addr;
const struct spi_buf tx_buf = {
.buf = &addr,
.len = 1
};
const struct spi_buf_set tx = {
.buffers = &tx_buf,
.count = 1
};
struct spi_buf rx_buf[2];
const struct spi_buf_set rx = {
.buffers = rx_buf,
.count = ARRAY_SIZE(rx_buf)
};
rx_buf[0].buf = NULL;
rx_buf[0].len = 1;
addr = start | BME680_SPI_READ_BIT;
rx_buf[1].buf = buf;
rx_buf[1].len = size;
err = bme680_set_mem_page(dev, start);
if (err) {
return err;
}
err = spi_transceive_dt(&config->bus.spi, &tx, &rx);
return err;
}
const struct bme680_bus_io bme680_bus_io_spi = {
.check = bme680_bus_check_spi,
.read = bme680_reg_read_spi,
.write = bme680_reg_write_spi,
};
#endif /* BME680_BUS_SPI */