zephyr/drivers/sensor/iis2mdc/iis2mdc_spi.c

115 lines
2.3 KiB
C

/* ST Microelectronics IIS2MDC 3-axis magnetometer sensor
*
* Copyright (c) 2020 STMicroelectronics
*
* SPDX-License-Identifier: Apache-2.0
*
* Datasheet:
* https://www.st.com/resource/en/datasheet/iis2mdc.pdf
*/
#define DT_DRV_COMPAT st_iis2mdc
#include <string.h>
#include "iis2mdc.h"
#include <logging/log.h>
#if DT_ANY_INST_ON_BUS_STATUS_OKAY(spi)
#define IIS2MDC_SPI_READ (1 << 7)
LOG_MODULE_DECLARE(IIS2MDC, CONFIG_SENSOR_LOG_LEVEL);
static int iis2mdc_spi_read(const struct device *dev, uint8_t reg,
uint8_t *val, uint16_t len)
{
const struct iis2mdc_dev_config *cfg = dev->config;
const struct spi_config *spi_cfg = &cfg->bus_cfg.spi_cfg;
uint8_t buffer_tx[2] = { reg | IIS2MDC_SPI_READ, 0 };
const struct spi_buf tx_buf = {
.buf = buffer_tx,
.len = 2,
};
const struct spi_buf_set tx = {
.buffers = &tx_buf,
.count = 1
};
const struct spi_buf rx_buf[2] = {
{
.buf = NULL,
.len = 1,
},
{
.buf = val,
.len = len,
}
};
const struct spi_buf_set rx = {
.buffers = rx_buf,
.count = 2
};
if (len > 64) {
return -EIO;
}
if (spi_transceive(cfg->bus, spi_cfg, &tx, &rx)) {
return -EIO;
}
return 0;
}
static int iis2mdc_spi_write(const struct device *dev, uint8_t reg,
uint8_t *val, uint16_t len)
{
const struct iis2mdc_dev_config *cfg = dev->config;
const struct spi_config *spi_cfg = &cfg->bus_cfg.spi_cfg;
uint8_t buffer_tx[1] = { reg & ~IIS2MDC_SPI_READ };
const struct spi_buf tx_buf[2] = {
{
.buf = buffer_tx,
.len = 1,
},
{
.buf = val,
.len = len,
}
};
const struct spi_buf_set tx = {
.buffers = tx_buf,
.count = 2
};
if (len > 64) {
return -EIO;
}
if (spi_write(cfg->bus, spi_cfg, &tx)) {
return -EIO;
}
return 0;
}
int iis2mdc_spi_init(const struct device *dev)
{
struct iis2mdc_data *data = dev->data;
const struct iis2mdc_dev_config *const cfg = dev->config;
const struct spi_cs_control *cs_ctrl = cfg->bus_cfg.spi_cfg.cs;
if (!device_is_ready(cs_ctrl->gpio_dev)) {
LOG_ERR("Cannot get pointer to CS gpio device");
return -ENODEV;
}
data->ctx_spi.read_reg = (stmdev_read_ptr) iis2mdc_spi_read;
data->ctx_spi.write_reg = (stmdev_write_ptr) iis2mdc_spi_write;
data->ctx = &data->ctx_spi;
data->ctx->handle = (void *)dev;
return 0;
}
#endif /* DT_ANY_INST_ON_BUS_STATUS_OKAY(spi) */