Just an inline comment; OK for the rest.

Il giorno gio 28 ott 2021 alle ore 13:05 Jonathan Cameron
[off-list ref] ha scritto:

On Thu, 28 Oct 2021 12:18:40 +0200
Andrea Merello [off-list ref] wrote:

quoted

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 <redacted>

Hi Andrea,

A few minor things inline.

Jonathan

quoted

---
 drivers/iio/imu/bno055/Kconfig      |  6 ++++
 drivers/iio/imu/bno055/Makefile     |  1 +
 drivers/iio/imu/bno055/bno055_i2c.c | 54 +++++++++++++++++++++++++++++
 3 files changed, 61 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 941e43f0368d..87200787d548 100644
--- a/drivers/iio/imu/bno055/Kconfig
+++ b/drivers/iio/imu/bno055/Kconfig

@@ -7,3 +7,9 @@ config BOSH_BNO055_SERIAL
      tristate "Bosh BNO055 attached via serial bus"
      depends on SERIAL_DEV_BUS
      select BOSH_BNO055_IIO
+
+config BOSH_BNO055_I2C
+     tristate "Bosh BNO055 attached via I2C bus"
+     depends on I2C
+     select REGMAP_I2C
+     select BOSH_BNO055_IIO

diff --git a/drivers/iio/imu/bno055/Makefile b/drivers/iio/imu/bno055/Makefile
index 7285ade2f4b9..eaf24018cb28 100644
--- a/drivers/iio/imu/bno055/Makefile
+++ b/drivers/iio/imu/bno055/Makefile

@@ -2,3 +2,4 @@

 obj-$(CONFIG_BOSH_BNO055_IIO) += bno055.o
 obj-$(CONFIG_BOSH_BNO055_SERIAL) += bno055_sl.o
+obj-$(CONFIG_BOSH_BNO055_I2C) += bno055_i2c.o

diff --git a/drivers/iio/imu/bno055/bno055_i2c.c b/drivers/iio/imu/bno055/bno055_i2c.c
new file mode 100644
index 000000000000..eea0daa6a61d
--- /dev/null
+++ b/drivers/iio/imu/bno055/bno055_i2c.c

@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * I2C interface for Bosh BNO055 IMU.
+ * This file implements I2C communication up to the register read/write
+ * level.

Not really. It just uses regmap, so I'd drop this comment.

quoted

+ *
+ * Copyright (C) 2021 Istituto Italiano di Tecnologia
+ * Electronic Design Laboratory
+ * Written by Andrea Merello [off-list ref]
+ */
+
+#include <linux/i2c.h>

Why?  I'm not seeing an i2c specific calls in here.

Because of the definition of struct i2c_client, that is being accessed
in lines like this
dev_err(&client->dev, "Unable to init register map");

quoted

+#include <linux/regmap.h>
+#include <linux/module.h>

mod_devicetable.h for struct i2c_device_id

quoted

+
+#include "bno055.h"
+
+#define BNO055_I2C_XFER_BURST_BREAK_THRESHOLD 3 /* FIXME */
+
+static int bno055_i2c_probe(struct i2c_client *client,
+                         const struct i2c_device_id *id)
+{
+     struct regmap *regmap =
+             devm_regmap_init_i2c(client, &bno055_regmap_config);
+
+     if (IS_ERR(regmap)) {
+             dev_err(&client->dev, "Unable to init register map");
+             return PTR_ERR(regmap);
+     }
+
+     return bno055_probe(&client->dev, regmap,
+                         BNO055_I2C_XFER_BURST_BREAK_THRESHOLD);
+
+     return 0;

?

quoted

+}
+
+static const struct i2c_device_id bno055_i2c_id[] = {
+     {"bno055", 0},
+     { },

It's at terminator, so don't put a comma as we'll never add entries after this.

quoted

+};
+MODULE_DEVICE_TABLE(i2c, bno055_i2c_id);
+
+static struct i2c_driver bno055_driver = {
+     .driver = {
+             .name = "bno055-i2c",
+     },
+     .probe = bno055_i2c_probe,
+     .id_table = bno055_i2c_id
+};
+module_i2c_driver(bno055_driver);
+
+MODULE_AUTHOR("Andrea Merello");
+MODULE_DESCRIPTION("Bosch BNO055 I2C interface");
+MODULE_LICENSE("GPL v2");