[v4 13/14] iio: imu: add BNO055 I2C driver

[Andrea Merello]

From: Andrea Merello <andrea.merello@xxxxxx>

This path adds an I2C driver for communicating to a BNO055 IMU via I2C
bus and it enables the BNO055 core driver to work in this scenario.

Signed-off-by: Andrea Merello <andrea.merello@xxxxxx>
---
 drivers/iio/imu/bno055/Kconfig      | 11 ++++++
 drivers/iio/imu/bno055/Makefile     |  1 +
 drivers/iio/imu/bno055/bno055_i2c.c | 56 +++++++++++++++++++++++++++++
 3 files changed, 68 insertions(+)
 create mode 100644 drivers/iio/imu/bno055/bno055_i2c.c

diff --git a/drivers/iio/imu/bno055/Kconfig b/drivers/iio/imu/bno055/Kconfig
index 5a1a574c9770..38b461646c02 100644
--- a/drivers/iio/imu/bno055/Kconfig
+++ b/drivers/iio/imu/bno055/Kconfig
@@ -18,3 +18,14 @@ config BOSCH_BNO055_SERDEV_TRACING
        depends on EVENT_TRACING && BOSCH_BNO055_SERIAL
        help
          Enable this to enable trace events for the BNO055 serdev driver.
+
+config BOSCH_BNO055_I2C
+	tristate "Bosch BNO055 attached via I2C bus"
+	depends on I2C
+	select REGMAP_I2C
+	select BOSCH_BNO055_IIO
+	help
+	  Enable this to support Bosch BNO055 IMUs attached via I2C bus.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called bno055_i2c.
diff --git a/drivers/iio/imu/bno055/Makefile b/drivers/iio/imu/bno055/Makefile
index 20128b1a1afc..20f911aad94b 100644
--- a/drivers/iio/imu/bno055/Makefile
+++ b/drivers/iio/imu/bno055/Makefile
@@ -2,5 +2,6 @@
 
 obj-$(CONFIG_BOSCH_BNO055_IIO) += bno055.o
 obj-$(CONFIG_BOSCH_BNO055_SERIAL) += bno055_ser.o
+obj-$(CONFIG_BOSCH_BNO055_I2C) += bno055_i2c.o
 
 CFLAGS_bno055_ser.o := -I$(src)
diff --git a/drivers/iio/imu/bno055/bno055_i2c.c b/drivers/iio/imu/bno055/bno055_i2c.c
new file mode 100644
index 000000000000..d59bb4e661be
--- /dev/null
+++ b/drivers/iio/imu/bno055/bno055_i2c.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Support for I2C-interfaced Bosch BNO055 IMU.
+ *
+ * Copyright (C) 2021-2022 Istituto Italiano di Tecnologia
+ * Electronic Design Laboratory
+ * Written by Andrea Merello <andrea.merello@xxxxxx>
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include "bno055.h"
+
+#define BNO055_I2C_XFER_BURST_BREAK_THRESHOLD 3 /* FIXME */
+
+static int bno055_i2c_probe(struct i2c_client *client)
+{
+	struct regmap *regmap;
+
+	regmap = devm_regmap_init_i2c(client, &bno055_regmap_config);
+	if (IS_ERR(regmap))
+		return dev_err_probe(&client->dev, PTR_ERR(regmap),
+				     "Unable to init register map");
+
+	return bno055_probe(&client->dev, regmap,
+			    BNO055_I2C_XFER_BURST_BREAK_THRESHOLD, true);
+}
+
+static const struct i2c_device_id bno055_i2c_id[] = {
+	{"bno055", 0},
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, bno055_i2c_id);
+
+static const struct of_device_id __maybe_unused bno055_i2c_of_match[] = {
+	{ .compatible = "bosch,bno055" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, bno055_i2c_of_match);
+
+static struct i2c_driver bno055_driver = {
+	.driver = {
+		.name = "bno055-i2c",
+		.of_match_table = of_match_ptr(bno055_i2c_of_match),
+	},
+	.probe_new = bno055_i2c_probe,
+	.id_table = bno055_i2c_id,
+};
+module_i2c_driver(bno055_driver);
+
+MODULE_AUTHOR("Andrea Merello");
+MODULE_DESCRIPTION("Bosch BNO055 I2C interface");
+MODULE_IMPORT_NS(IIO_BNO055);
+MODULE_LICENSE("GPL");
-- 
2.17.1