zephyr/drivers/sensor/lis2dw12/lis2dw12_spi.c

127 lines
2.6 KiB
C

/* ST Microelectronics LIS2DW12 3-axis accelerometer driver
*
* Copyright (c) 2019 STMicroelectronics
*
* SPDX-License-Identifier: Apache-2.0
*
* Datasheet:
* https://www.st.com/resource/en/datasheet/lis2dw12.pdf
*/
#include <string.h>
#include "lis2dw12.h"
#include <logging/log.h>
#ifdef DT_ST_LIS2DW12_BUS_SPI
#define LIS2DW12_SPI_READ (1 << 7)
LOG_MODULE_DECLARE(LIS2DW12, CONFIG_SENSOR_LOG_LEVEL);
static struct spi_config lis2dw12_spi_conf = {
.frequency = DT_INST_0_ST_LIS2DW12_SPI_MAX_FREQUENCY,
.operation = (SPI_OP_MODE_MASTER | SPI_MODE_CPOL |
SPI_MODE_CPHA | SPI_WORD_SET(8) | SPI_LINES_SINGLE),
.slave = DT_INST_0_ST_LIS2DW12_BASE_ADDRESS,
.cs = NULL,
};
static int lis2dw12_spi_read(struct lis2dw12_data *ctx, u8_t reg,
u8_t *data, u16_t len)
{
struct spi_config *spi_cfg = &lis2dw12_spi_conf;
u8_t buffer_tx[2] = { reg | LIS2DW12_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 = 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 lis2dw12_spi_write(struct lis2dw12_data *ctx, u8_t reg,
u8_t *data, u16_t len)
{
struct spi_config *spi_cfg = &lis2dw12_spi_conf;
u8_t buffer_tx[1] = { reg & ~LIS2DW12_SPI_READ };
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 lis2dw12_spi_ctx = {
.read_reg = (stmdev_read_ptr) lis2dw12_spi_read,
.write_reg = (stmdev_write_ptr) lis2dw12_spi_write,
};
int lis2dw12_spi_init(struct device *dev)
{
struct lis2dw12_data *data = dev->driver_data;
data->ctx = &lis2dw12_spi_ctx;
data->ctx->handle = data;
#if defined(DT_INST_0_ST_LIS2DW12_CS_GPIOS_CONTROLLER)
/* handle SPI CS thru GPIO if it is the case */
data->cs_ctrl.gpio_dev = device_get_binding(
DT_INST_0_ST_LIS2DW12_CS_GPIOS_CONTROLLER);
if (!data->cs_ctrl.gpio_dev) {
LOG_ERR("Unable to get GPIO SPI CS device");
return -ENODEV;
}
data->cs_ctrl.gpio_pin = DT_INST_0_ST_LIS2DW12_CS_GPIOS_PIN;
data->cs_ctrl.delay = 0U;
lis2dw12_spi_conf.cs = &data->cs_ctrl;
LOG_DBG("SPI GPIO CS configured on %s:%u",
DT_INST_0_ST_LIS2DW12_CS_GPIOS_CONTROLLER,
DT_INST_0_ST_LIS2DW12_CS_GPIOS_PIN);
#endif
return 0;
}
#endif /* DT_ST_LIS2DW12_BUS_SPI */