iio: gyro: fxas2100x: add i2c driver

This add the real driver to talk over i2c and use the fxas2100x core
for the main tasks.

Reviewed-by: Jun Nie <jun.nie@linaro.org>
Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>

3 files changed, 81 insertions, 0 deletions

diff --git a/drivers/iio/gyro/Kconfig b/drivers/iio/gyro/Kconfig
index c168aa63de3b..1f9bfc51febb 100644
--- a/drivers/iio/gyro/Kconfig
+++ b/drivers/iio/gyro/Kconfig
@@ -77,6 +77,8 @@ config FXAS2100X
 	tristate "NXP FXAS2100X Gyro Sensor"
 	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
+	select FXAS2100X_I2C if (I2C)
+	depends on (I2C || SPI_MASTER)
 	help
 	  Say yes here to build support for NXP FXAS2100X family Tri-axis Gyro
 	  Sensor driver connected via I2C or SPI.
@@ -84,6 +86,10 @@ config FXAS2100X
 	  This driver can also be built as a module.  If so, the module
 	  will be called fxas2100x_i2c or fxas2100x_spi.
 
+config FXAS2100X_I2C
+	tristate
+	select REGMAP_I2C
+
 config HID_SENSOR_GYRO_3D
 	depends on HID_SENSOR_HUB
 	select IIO_BUFFER
diff --git a/drivers/iio/gyro/Makefile b/drivers/iio/gyro/Makefile
index 9e2395185a6e..8b1540ddbbce 100644
--- a/drivers/iio/gyro/Makefile
+++ b/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_FXAS2100X) += fxas2100x_core.o
+obj-$(CONFIG_FXAS2100X_I2C) += fxas2100x_i2c.o
 
 obj-$(CONFIG_HID_SENSOR_GYRO_3D) += hid-sensor-gyro-3d.o
 
diff --git a/drivers/iio/gyro/fxas2100x_i2c.c b/drivers/iio/gyro/fxas2100x_i2c.c
new file mode 100644
index 000000000000..2e25c5ef4130
--- /dev/null
+++ b/drivers/iio/gyro/fxas2100x_i2c.c
@@ -0,0 +1,74 @@
+/*
+ * Driver for NXP FXAS2100x Gyroscope - I2C
+ *
+ * Copyright (C) 2017 Linaro Ltd.
+ *
+ */
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+#include "fxas2100x.h"
+
+static const struct regmap_config fxas2100x_regmap_i2c_conf = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = FXAS2100X_REG_CTRL3,
+};
+
+static int fxas2100x_i2c_probe(struct i2c_client *i2c,
+			       const struct i2c_device_id *id)
+{
+	struct regmap *regmap;
+	const char *name = NULL;
+
+	regmap = devm_regmap_init_i2c(i2c, &fxas2100x_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);
+	}
+
+	if (id)
+		name = id->name;
+
+	return fxas2100x_core_probe(&i2c->dev, regmap, i2c->irq, name);
+}
+
+static int fxas2100x_i2c_remove(struct i2c_client *i2c)
+{
+	fxas2100x_core_remove(&i2c->dev);
+
+	return 0;
+}
+
+static const struct i2c_device_id fxas2100x_i2c_id[] = {
+	{ "fxas2100x", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, fxas2100x_i2c_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id fxas2100x_i2c_of_match[] = {
+	{ .compatible = "nxp,fxas2100x", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, fxas2100x_i2c_of_match);
+#endif
+
+static struct i2c_driver fxas2100x_i2c_driver = {
+	.driver = {
+		.name = "fxas2100x_i2c",
+		.pm = &fxas2100x_pm_ops,
+		.of_match_table = of_match_ptr(fxas2100x_i2c_of_match),
+	},
+	.probe		= fxas2100x_i2c_probe,
+	.remove		= fxas2100x_i2c_remove,
+	.id_table	= fxas2100x_i2c_id,
+};
+module_i2c_driver(fxas2100x_i2c_driver);
+
+MODULE_AUTHOR("Rui Miguel Silva <rui.silva@linaro.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("FXAS2100X I2C Gyro driver");