[PATCH v4 3/4] iio: accel: adxl345: Split driver into core and I2C

From: Eva Rachel Retuya
Date: Sun Feb 26 2017 - 08:48:29 EST

Move I2C-specific code into its own file and rely on regmap to access
registers. The core code provides access to x, y, z and scale readings.

Signed-off-by: Eva Rachel Retuya <eraretuya@xxxxxxxxx>
---
Changes from v3:
* Revert to explicit and separate I2C and SPI configuration
* Add OF match table, make it enumerable in ACPI environment (Andy's suggestion)

drivers/iio/accel/Kconfig | 11 +++-
drivers/iio/accel/Makefile | 3 +-
drivers/iio/accel/adxl345.h | 18 ++++++
drivers/iio/accel/{adxl345.c => adxl345_core.c} | 55 ++++-------------
drivers/iio/accel/adxl345_i2c.c | 78 +++++++++++++++++++++++++
5 files changed, 117 insertions(+), 48 deletions(-)
create mode 100644 drivers/iio/accel/adxl345.h
rename drivers/iio/accel/{adxl345.c => adxl345_core.c} (78%)
create mode 100644 drivers/iio/accel/adxl345_i2c.c

diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 26b8614..9f5a889 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -6,16 +6,21 @@
menu "Accelerometers"

config ADXL345
- tristate "Analog Devices ADXL345 3-Axis Digital Accelerometer Driver"
+ tristate
+
+config ADXL345_I2C
+ tristate "Analog Devices ADXL345 3-Axis Digital Accelerometer I2C Driver"
depends on !(INPUT_ADXL34X=y || INPUT_ADXL34X=m)
depends on I2C
+ select ADXL345
select REGMAP_I2C
help
Say Y here if you want to build support for the Analog Devices
ADXL345 3-axis digital accelerometer.

- To compile this driver as a module, choose M here: the
- module will be called adxl345.
+ To compile this driver as a module, choose M here: the module
+ will be called adxl345_i2c and you will also get adxl345_core
+ for the core module.

config BMA180
tristate "Bosch BMA180/BMA250 3-Axis Accelerometer Driver"
diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index 618488d..3f4a6d6 100644
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -3,7 +3,8 @@
#

# When adding new entries keep the list in alphabetical order
-obj-$(CONFIG_ADXL345) += adxl345.o
+obj-$(CONFIG_ADXL345) += adxl345_core.o
+obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
obj-$(CONFIG_BMA180) += bma180.o
obj-$(CONFIG_BMA220) += bma220_spi.o
obj-$(CONFIG_BMC150_ACCEL) += bmc150-accel-core.o
diff --git a/drivers/iio/accel/adxl345.h b/drivers/iio/accel/adxl345.h
new file mode 100644
index 0000000..fca3e25
--- /dev/null
+++ b/drivers/iio/accel/adxl345.h
@@ -0,0 +1,18 @@
+/*
+ * ADXL345 3-Axis Digital Accelerometer
+ *
+ * Copyright (c) 2017 Eva Rachel Retuya <eraretuya@xxxxxxxxx>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License. See the file COPYING in the main
+ * directory of this archive for more details.
+ */
+
+#ifndef _ADXL345_H_
+#define _ADXL345_H_
+
+int adxl345_common_probe(struct device *dev, struct regmap *regmap,
+ const char *name);
+int adxl345_common_remove(struct device *dev);
+
+#endif /* _ADXL345_H_ */
diff --git a/drivers/iio/accel/adxl345.c b/drivers/iio/accel/adxl345_core.c
similarity index 78%
rename from drivers/iio/accel/adxl345.c
rename to drivers/iio/accel/adxl345_core.c
index bec8bec..9dea6a5 100644
--- a/drivers/iio/accel/adxl345.c
+++ b/drivers/iio/accel/adxl345_core.c
@@ -7,17 +7,16 @@
* the GNU General Public License. See the file COPYING in the main
* directory of this archive for more details.
*
- * IIO driver for ADXL345
- * 7-bit I2C slave address: 0x1D (ALT ADDRESS pin tied to VDDIO) or
- * 0x53 (ALT ADDRESS pin grounded)
+ * IIO core driver for ADXL345
*/

-#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/regmap.h>

#include <linux/iio/iio.h>

+#include "adxl345.h"
+
#define ADXL345_REG_DEVID 0x00
#define ADXL345_REG_POWER_CTL 0x2D
#define ADXL345_REG_DATA_FORMAT 0x31
@@ -50,11 +49,6 @@ struct adxl345_data {
u8 data_range;
};

-static const struct regmap_config adxl345_regmap_config = {
- .reg_bits = 8,
- .val_bits = 8,
-};
-
#define ADXL345_CHANNEL(reg, axis) { \
.type = IIO_ACCEL, \
.modified = 1, \
@@ -107,25 +101,14 @@ static const struct iio_info adxl345_info = {
.read_raw = adxl345_read_raw,
};

-static int adxl345_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
+int adxl345_common_probe(struct device *dev, struct regmap *regmap,
+ const char *name)
{
struct adxl345_data *data;
struct iio_dev *indio_dev;
- struct device *dev;
- struct regmap *regmap;
int ret;
u32 regval;

- regmap = devm_regmap_init_i2c(client, &adxl345_regmap_config);
- if (IS_ERR(regmap)) {
- dev_err(&client->dev, "Error initializing regmap: %d\n",
- (int)PTR_ERR(regmap));
- return PTR_ERR(regmap);
- }
-
- dev = regmap_get_device(regmap);
-
ret = regmap_read(regmap, ADXL345_REG_DEVID, &regval);
if (ret < 0) {
dev_err(dev, "Error reading device ID: %d\n", ret);
@@ -156,7 +139,7 @@ static int adxl345_probe(struct i2c_client *client,
}

indio_dev->dev.parent = dev;
- indio_dev->name = id->name;
+ indio_dev->name = name;
indio_dev->info = &adxl345_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = adxl345_channels;
@@ -179,10 +162,11 @@ static int adxl345_probe(struct i2c_client *client,

return ret;
}
+EXPORT_SYMBOL_GPL(adxl345_common_probe);

-static int adxl345_remove(struct i2c_client *client)
+int adxl345_common_remove(struct device *dev)
{
- struct iio_dev *indio_dev = i2c_get_clientdata(client);
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct adxl345_data *data = iio_priv(indio_dev);

iio_device_unregister(indio_dev);
@@ -190,25 +174,8 @@ static int adxl345_remove(struct i2c_client *client)
return regmap_write(data->regmap, ADXL345_REG_POWER_CTL,
ADXL345_POWER_CTL_STANDBY);
}
-
-static const struct i2c_device_id adxl345_i2c_id[] = {
- { "adxl345", 0 },
- { }
-};
-
-MODULE_DEVICE_TABLE(i2c, adxl345_i2c_id);
-
-static struct i2c_driver adxl345_driver = {
- .driver = {
- .name = "adxl345",
- },
- .probe = adxl345_probe,
- .remove = adxl345_remove,
- .id_table = adxl345_i2c_id,
-};
-
-module_i2c_driver(adxl345_driver);
+EXPORT_SYMBOL_GPL(adxl345_common_remove);

MODULE_AUTHOR("Eva Rachel Retuya <eraretuya@xxxxxxxxx>");
-MODULE_DESCRIPTION("ADXL345 3-Axis Digital Accelerometer driver");
+MODULE_DESCRIPTION("ADXL345 3-Axis Digital Accelerometer core driver");
MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/accel/adxl345_i2c.c b/drivers/iio/accel/adxl345_i2c.c
new file mode 100644
index 0000000..19053be
--- /dev/null
+++ b/drivers/iio/accel/adxl345_i2c.c
@@ -0,0 +1,78 @@
+/*
+ * ADXL345 3-Axis Digital Accelerometer
+ *
+ * Copyright (c) 2017 Eva Rachel Retuya <eraretuya@xxxxxxxxx>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License. See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * I2C driver for ADXL345
+ * 7-bit I2C slave address: 0x1D (ALT ADDRESS pin tied to VDDIO) or
+ * 0x53 (ALT ADDRESS pin grounded)
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include "adxl345.h"
+
+static const struct regmap_config adxl345_i2c_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+};
+
+static int adxl345_i2c_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct regmap *regmap;
+ const char *name = NULL;
+
+ regmap = devm_regmap_init_i2c(client, &adxl345_i2c_regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(&client->dev, "Error initializing i2c regmap: %d\n",
+ (int)PTR_ERR(regmap));
+ return PTR_ERR(regmap);
+ }
+
+ if (id)
+ name = id->name;
+
+ return adxl345_common_probe(&client->dev, regmap, name);
+}
+
+static int adxl345_i2c_remove(struct i2c_client *client)
+{
+ return adxl345_common_remove(&client->dev);
+}
+
+static const struct i2c_device_id adxl345_i2c_id[] = {
+ { "adxl345", 0 },
+ { }
+};
+
+MODULE_DEVICE_TABLE(i2c, adxl345_i2c_id);
+
+static const struct of_device_id adxl345_of_match[] = {
+ { .compatible = "adi,adxl345" },
+ { },
+};
+
+MODULE_DEVICE_TABLE(of, adxl345_of_match);
+
+static struct i2c_driver adxl345_i2c_driver = {
+ .driver = {
+ .name = "adxl345_i2c",
+ .of_match_table = adxl345_of_match,
+ },
+ .probe = adxl345_i2c_probe,
+ .remove = adxl345_i2c_remove,
+ .id_table = adxl345_i2c_id,
+};
+
+module_i2c_driver(adxl345_i2c_driver);
+
+MODULE_AUTHOR("Eva Rachel Retuya <eraretuya@xxxxxxxxx>");
+MODULE_DESCRIPTION("ADXL345 3-Axis Digital Accelerometer I2C driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4