zephyr/drivers/sensor/iis2dh/iis2dh_spi.c

129 lines
2.7 KiB
C

/* ST Microelectronics IIS2DH 3-axis accelerometer driver
*
* Copyright (c) 2020 STMicroelectronics
*
* SPDX-License-Identifier: Apache-2.0
*
* Datasheet:
* https://www.st.com/resource/en/datasheet/iis2dh.pdf
*/
#define DT_DRV_COMPAT st_iis2dh
#include <string.h>
#include "iis2dh.h"
#include <logging/log.h>
#if DT_ANY_INST_ON_BUS_STATUS_OKAY(spi)
#define IIS2DH_SPI_READM (3 << 6) /* 0xC0 */
#define IIS2DH_SPI_WRITEM (1 << 6) /* 0x40 */
LOG_MODULE_DECLARE(IIS2DH, CONFIG_SENSOR_LOG_LEVEL);
static struct spi_config iis2dh_spi_conf = {
.frequency = DT_INST_PROP(0, spi_max_frequency),
.operation = (SPI_OP_MODE_MASTER | SPI_MODE_CPOL |
SPI_MODE_CPHA | SPI_WORD_SET(8)),
.slave = DT_INST_REG_ADDR(0),
.cs = NULL,
};
static int iis2dh_spi_read(struct iis2dh_data *ctx, uint8_t reg,
uint8_t *data, uint16_t len)
{
struct spi_config *spi_cfg = &iis2dh_spi_conf;
uint8_t buffer_tx[2] = { reg | IIS2DH_SPI_READM, 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 = data,
.len = len,
}
};
const struct spi_buf_set rx = {
.buffers = rx_buf,
.count = 2
};
if (spi_transceive(ctx->bus, spi_cfg, &tx, &rx)) {
return -EIO;
}
return 0;
}
static int iis2dh_spi_write(struct iis2dh_data *ctx, uint8_t reg,
uint8_t *data, uint16_t len)
{
struct spi_config *spi_cfg = &iis2dh_spi_conf;
uint8_t buffer_tx[1] = { reg | IIS2DH_SPI_WRITEM };
const struct spi_buf tx_buf[2] = {
{
.buf = buffer_tx,
.len = 1,
},
{
.buf = data,
.len = len,
}
};
const struct spi_buf_set tx = {
.buffers = tx_buf,
.count = 2
};
if (spi_write(ctx->bus, spi_cfg, &tx)) {
return -EIO;
}
return 0;
}
stmdev_ctx_t iis2dh_spi_ctx = {
.read_reg = (stmdev_read_ptr) iis2dh_spi_read,
.write_reg = (stmdev_write_ptr) iis2dh_spi_write,
};
int iis2dh_spi_init(const struct device *dev)
{
struct iis2dh_data *data = dev->data;
data->ctx = &iis2dh_spi_ctx;
data->ctx->handle = data;
#if DT_INST_SPI_DEV_HAS_CS_GPIOS(0)
/* handle SPI CS thru GPIO if it is the case */
data->cs_ctrl.gpio_dev = device_get_binding(
DT_INST_SPI_DEV_CS_GPIOS_LABEL(0));
if (!data->cs_ctrl.gpio_dev) {
LOG_ERR("Unable to get GPIO SPI CS device");
return -ENODEV;
}
data->cs_ctrl.gpio_pin = DT_INST_SPI_DEV_CS_GPIOS_PIN(0);
data->cs_ctrl.delay = 0U;
iis2dh_spi_conf.cs = &data->cs_ctrl;
LOG_DBG("SPI GPIO CS configured on %s:%u",
DT_INST_SPI_DEV_CS_GPIOS_LABEL(0),
DT_INST_SPI_DEV_CS_GPIOS_PIN(0));
#endif
return 0;
}
#endif /* DT_ANY_INST_ON_BUS_STATUS_OKAY(spi) */