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1// SPDX-License-Identifier: GPL-2.02/*3 * SPI driver for Bosch BMI323 6-Axis IMU.4 *5 * Copyright (C) 2023, Jagath Jog J <jagathjog1996@gmail.com>6 */7 8#include <linux/mod_devicetable.h>9#include <linux/module.h>10#include <linux/regmap.h>11#include <linux/spi/spi.h>12 13#include "bmi323.h"14 15/*16 * From BMI323 datasheet section 4: Notes on the Serial Interface Support.17 * Each SPI register read operation requires to read one dummy byte before18 * the actual payload.19 */20static int bmi323_regmap_spi_read(void *context, const void *reg_buf,21 size_t reg_size, void *val_buf,22 size_t val_size)23{24 struct spi_device *spi = context;25 26 return spi_write_then_read(spi, reg_buf, reg_size, val_buf, val_size);27}28 29static int bmi323_regmap_spi_write(void *context, const void *data,30 size_t count)31{32 struct spi_device *spi = context;33 u8 *data_buff = (u8 *)data;34 35 data_buff[1] = data_buff[0];36 return spi_write(spi, data_buff + 1, count - 1);37}38 39static const struct regmap_bus bmi323_regmap_bus = {40 .read = bmi323_regmap_spi_read,41 .write = bmi323_regmap_spi_write,42};43 44static const struct regmap_config bmi323_spi_regmap_config = {45 .reg_bits = 8,46 .val_bits = 16,47 .pad_bits = 8,48 .read_flag_mask = BIT(7),49 .max_register = BMI323_CFG_RES_REG,50 .val_format_endian = REGMAP_ENDIAN_LITTLE,51};52 53static int bmi323_spi_probe(struct spi_device *spi)54{55 struct device *dev = &spi->dev;56 struct regmap *regmap;57 58 regmap = devm_regmap_init(dev, &bmi323_regmap_bus, dev,59 &bmi323_spi_regmap_config);60 if (IS_ERR(regmap))61 return dev_err_probe(dev, PTR_ERR(regmap),62 "Failed to initialize SPI Regmap\n");63 64 return bmi323_core_probe(dev);65}66 67static const struct spi_device_id bmi323_spi_ids[] = {68 { "bmi323" },69 { }70};71MODULE_DEVICE_TABLE(spi, bmi323_spi_ids);72 73static const struct of_device_id bmi323_of_spi_match[] = {74 { .compatible = "bosch,bmi323" },75 { }76};77MODULE_DEVICE_TABLE(of, bmi323_of_spi_match);78 79static struct spi_driver bmi323_spi_driver = {80 .driver = {81 .name = "bmi323",82 .pm = pm_ptr(&bmi323_core_pm_ops),83 .of_match_table = bmi323_of_spi_match,84 },85 .probe = bmi323_spi_probe,86 .id_table = bmi323_spi_ids,87};88module_spi_driver(bmi323_spi_driver);89 90MODULE_DESCRIPTION("Bosch BMI323 IMU driver");91MODULE_AUTHOR("Jagath Jog J <jagathjog1996@gmail.com>");92MODULE_LICENSE("GPL");93MODULE_IMPORT_NS(IIO_BMI323);94