iio: gyro: fxas21002c: add i2c driver

Add the real driver to talk over i2c and use the fxas21002c core
for the main tasks.
Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/gyro/Kconfig

@@ -77,6 +77,8 @@ config FXAS21002C
        tristate "NXP FXAS21002C Gyro Sensor"
        select IIO_BUFFER
        select IIO_TRIGGERED_BUFFER
+       select FXAS21002C_I2C if (I2C)
+       depends on I2C
        help
          Say yes here to build support for NXP FXAS21002C Tri-axis Gyro
          Sensor driver connected via I2C or SPI.
@@ -84,6 +86,10 @@ config FXAS21002C
          This driver can also be built as a module.  If so, the module
          will be called fxas21002c_i2c or fxas21002c_spi.
 
+config FXAS21002C_I2C
+       tristate
+       select REGMAP_I2C
+
 config HID_SENSOR_GYRO_3D
 	depends on HID_SENSOR_HUB
 	select IIO_BUFFER

drivers/iio/gyro/Makefile

@@ -13,6 +13,7 @@ obj-$(CONFIG_BMG160) += bmg160_core.o
 obj-$(CONFIG_BMG160_I2C) += bmg160_i2c.o
 obj-$(CONFIG_BMG160_SPI) += bmg160_spi.o
 obj-$(CONFIG_FXAS21002C) += fxas21002c_core.o
+obj-$(CONFIG_FXAS21002C_I2C) += fxas21002c_i2c.o
 
 obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o
 

drivers/iio/gyro/fxas21002c_i2c.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for NXP FXAS21002C Gyroscope - I2C
+ *
+ * Copyright (C) 2018 Linaro Ltd.
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include "fxas21002c.h"
+
+static const struct regmap_config fxas21002c_regmap_i2c_conf = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = FXAS21002C_REG_CTRL3,
+};
+
+static int fxas21002c_i2c_probe(struct i2c_client *i2c)
+{
+	struct regmap *regmap;
+
+	regmap = devm_regmap_init_i2c(i2c, &fxas21002c_regmap_i2c_conf);
+	if (IS_ERR(regmap)) {
+		dev_err(&i2c->dev, "Failed to register i2c regmap: %ld\n",
+			PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	return fxas21002c_core_probe(&i2c->dev, regmap, i2c->irq, i2c->name);
+}
+
+static int fxas21002c_i2c_remove(struct i2c_client *i2c)
+{
+	fxas21002c_core_remove(&i2c->dev);
+
+	return 0;
+}
+
+static const struct i2c_device_id fxas21002c_i2c_id[] = {
+	{ "fxas21002c", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, fxas21002c_i2c_id);
+
+static const struct of_device_id fxas21002c_i2c_of_match[] = {
+	{ .compatible = "nxp,fxas21002c", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, fxas21002c_i2c_of_match);
+
+static struct i2c_driver fxas21002c_i2c_driver = {
+	.driver = {
+		.name = "fxas21002c_i2c",
+		.pm = &fxas21002c_pm_ops,
+		.of_match_table = fxas21002c_i2c_of_match,
+	},
+	.probe_new	= fxas21002c_i2c_probe,
+	.remove		= fxas21002c_i2c_remove,
+	.id_table	= fxas21002c_i2c_id,
+};
+module_i2c_driver(fxas21002c_i2c_driver);
+
+MODULE_AUTHOR("Rui Miguel Silva <rui.silva@linaro.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("FXAS21002C I2C Gyro driver");