// SPDX-License-Identifier: GPL-2.0-only /* * STMicroelectronics sensors spi library driver * * Copyright 2012-2013 STMicroelectronics Inc. * * Denis Ciocca <denis.ciocca@st.com> */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/iio/iio.h> #include <linux/property.h> #include <linux/regmap.h> #include <linux/iio/common/st_sensors_spi.h> #include "st_sensors_core.h" #define ST_SENSORS_SPI_MULTIREAD 0xc0 static const struct regmap_config st_sensors_spi_regmap_config = { .reg_bits = 8, .val_bits = 8, }; static const struct regmap_config st_sensors_spi_regmap_multiread_bit_config = { .reg_bits = 8, .val_bits = 8, .read_flag_mask = ST_SENSORS_SPI_MULTIREAD, }; /* * st_sensors_is_spi_3_wire() - check if SPI 3-wire mode has been selected * @spi: spi device reference. * * Return: true if SPI 3-wire mode is selected, false otherwise. */ static bool st_sensors_is_spi_3_wire(struct spi_device *spi) { struct st_sensors_platform_data *pdata; struct device *dev = &spi->dev; if (device_property_read_bool(dev, "spi-3wire")) return true; pdata = dev_get_platdata(dev); if (pdata && pdata->spi_3wire) return true; return false; } /* * st_sensors_configure_spi_3_wire() - configure SPI 3-wire if needed * @spi: spi device reference. * @settings: sensor specific settings reference. * * Return: 0 on success, else a negative error code. */ static int st_sensors_configure_spi_3_wire(struct spi_device *spi, struct st_sensor_settings *settings) { if (settings->sim.addr) { u8 buffer[] = { settings->sim.addr, settings->sim.value }; return spi_write(spi, buffer, 2); } return 0; } /* * st_sensors_spi_configure() - configure SPI interface * @indio_dev: IIO device reference. * @spi: spi device reference. * * Return: 0 on success, else a negative error code. */ int st_sensors_spi_configure(struct iio_dev *indio_dev, struct spi_device *spi) { struct st_sensor_data *sdata = iio_priv(indio_dev); const struct regmap_config *config; int err; if (st_sensors_is_spi_3_wire(spi)) { err = st_sensors_configure_spi_3_wire(spi, sdata->sensor_settings); if (err < 0) return err; } if (sdata->sensor_settings->multi_read_bit) config = &st_sensors_spi_regmap_multiread_bit_config; else config = &st_sensors_spi_regmap_config; sdata->regmap = devm_regmap_init_spi(spi, config); if (IS_ERR(sdata->regmap)) { dev_err(&spi->dev, "Failed to register spi regmap (%ld)\n", PTR_ERR(sdata->regmap)); return PTR_ERR(sdata->regmap); } spi_set_drvdata(spi, indio_dev); indio_dev->dev.parent = &spi->dev; indio_dev->name = spi->modalias; sdata->dev = &spi->dev; sdata->irq = spi->irq; return 0; } EXPORT_SYMBOL(st_sensors_spi_configure); MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>"); MODULE_DESCRIPTION("STMicroelectronics ST-sensors spi driver"); MODULE_LICENSE("GPL v2");