1 files changed, 92 insertions, 0 deletions
diff --git a/drivers/iio/imu/bmi323/bmi323_spi.c b/drivers/iio/imu/bmi323/bmi323_spi.c
new file mode 100644
index 00000000000000..7b1e8127d0dd9b
--- /dev/null
+++ b/drivers/iio/imu/bmi323/bmi323_spi.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SPI driver for Bosch BMI323 6-Axis IMU.
+ *
+ * Copyright (C) 2023, Jagath Jog J <jagathjog1996@gmail.com>
+ */
+
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+#include "bmi323.h"
+
+/*
+ * From BMI323 datasheet section 4: Notes on the Serial Interface Support.
+ * Each SPI register read operation requires to read one dummy byte before
+ * the actual payload.
+ */
+static int bmi323_regmap_spi_read(void *context, const void *reg_buf,
+				  size_t reg_size, void *val_buf,
+				  size_t val_size)
+{
+	struct spi_device *spi = context;
+
+	return spi_write_then_read(spi, reg_buf, reg_size, val_buf, val_size);
+}
+
+static int bmi323_regmap_spi_write(void *context, const void *data,
+				   size_t count)
+{
+	struct spi_device *spi = context;
+	u8 *data_buff = (u8 *)data;
+
+	data_buff[1] = data_buff[0];
+	return spi_write(spi, data_buff + 1, count - 1);
+}
+
+static struct regmap_bus bmi323_regmap_bus = {
+	.read = bmi323_regmap_spi_read,
+	.write = bmi323_regmap_spi_write,
+};
+
+static const struct regmap_config bmi323_spi_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 16,
+	.pad_bits = 8,
+	.read_flag_mask = BIT(7),
+	.max_register = BMI323_CFG_RES_REG,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
+};
+
+static int bmi323_spi_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct regmap *regmap;
+
+	regmap = devm_regmap_init(dev, &bmi323_regmap_bus, dev,
+				  &bmi323_spi_regmap_config);
+	if (IS_ERR(regmap))
+		return dev_err_probe(dev, PTR_ERR(regmap),
+				     "Failed to initialize SPI Regmap\n");
+
+	return bmi323_core_probe(dev);
+}
+
+static const struct spi_device_id bmi323_spi_ids[] = {
+	{ "bmi323" },
+	{ }
+};
+MODULE_DEVICE_TABLE(spi, bmi323_spi_ids);
+
+static const struct of_device_id bmi323_of_spi_match[] = {
+	{ .compatible = "bosch,bmi323" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, bmi323_of_spi_match);
+
+static struct spi_driver bmi323_spi_driver = {
+	.driver = {
+		.name = "bmi323",
+		.of_match_table = bmi323_of_spi_match,
+	},
+	.probe = bmi323_spi_probe,
+	.id_table = bmi323_spi_ids,
+};
+module_spi_driver(bmi323_spi_driver);
+
+MODULE_DESCRIPTION("Bosch BMI323 IMU driver");
+MODULE_AUTHOR("Jagath Jog J <jagathjog1996@gmail.com>");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(IIO_BMI323);