[PATCH] iio: accel: Add driver for the mCube MC3230 3-axis accelerometer

[PATCH] iio: accel: Add driver for the mCube MC3230 3-axis accelerometer

[Hans de Goede]

Add an IIO driver for the mCube MC3230 3-axis accelerometer.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 .../devicetree/bindings/i2c/trivial-devices.txt    |   1 +
 drivers/iio/accel/Kconfig                          |  10 +
 drivers/iio/accel/Makefile                         |   1 +
 drivers/iio/accel/mc3230.c                         | 225 +++++++++++++++++++++
 4 files changed, 237 insertions(+)
 create mode 100644 drivers/iio/accel/mc3230.c

diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
index badf5eb..fbbad64 100644
--- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
+++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
@@ -56,6 +56,7 @@ maxim,ds1050		5 Bit Programmable, Pulse-Width Modulator
 maxim,max1237		Low-Power, 4-/12-Channel, 2-Wire Serial, 12-Bit ADCs
 maxim,max6625		9-Bit/12-Bit Temperature Sensors with I²C-Compatible Serial Interface
 mc,rv3029c2		Real Time Clock Module with I2C-Bus
+mcube,mc3230		mCube 3-axis 8-bit digital accelerometer
 microchip,mcp4531-502	Microchip 7-bit Single I2C Digital Potentiometer (5k)
 microchip,mcp4531-103	Microchip 7-bit Single I2C Digital Potentiometer (10k)
 microchip,mcp4531-503	Microchip 7-bit Single I2C Digital Potentiometer (50k)
diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 5630f23..3aee97d 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -138,6 +138,16 @@ config KXCJK1013
 	  To compile this driver as a module, choose M here: the module will
 	  be called kxcjk-1013.
 
+config MC3230
+	tristate "mCube MC3230 Digital Accelerometer Driver"
+	depends on I2C
+	help
+	  Say yes here to build support for the mCube MC3230 low-g tri-axial
+	  digital accelerometer.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called mc3230.
+
 config MMA7455
 	tristate
 	select IIO_BUFFER
diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index e974841..07a0c72 100644
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_DMARD09)	+= dmard09.o
 obj-$(CONFIG_HID_SENSOR_ACCEL_3D) += hid-sensor-accel-3d.o
 obj-$(CONFIG_KXCJK1013) += kxcjk-1013.o
 obj-$(CONFIG_KXSD9)	+= kxsd9.o
+obj-$(CONFIG_MC3230)	+= mc3230.o
 
 obj-$(CONFIG_MMA7455)		+= mma7455_core.o
 obj-$(CONFIG_MMA7455_I2C)	+= mma7455_i2c.o
diff --git a/drivers/iio/accel/mc3230.c b/drivers/iio/accel/mc3230.c
new file mode 100644
index 0000000..21127a9
--- /dev/null
+++ b/drivers/iio/accel/mc3230.c
@@ -0,0 +1,225 @@
+/**
+ * mCube MC3230 3-Axis Accelerometer
+ *
+ * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * IIO driver for mCube MC3230; 7-bit I2C address: 0x4c.
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define MC3230_REG_XOUT			0x00
+#define MC3230_REG_YOUT			0x01
+#define MC3230_REG_ZOUT			0x02
+
+#define MC3230_REG_MODE			0x07
+#define MC3230_MODE_OPCON_MASK		0x03
+#define MC3230_MODE_OPCON_WAKE		0x01
+#define MC3230_MODE_OPCON_STANDBY	0x03
+
+#define MC3230_REG_CHIP_ID		0x18
+#define MC3230_CHIP_ID			0x01
+
+#define MC3230_REG_PRODUCT_CODE		0x3b
+#define MC3230_PRODUCT_CODE		0x19
+
+/*
+ * The accelerometer has one measurement range:
+ *
+ * -1.5g - +1.5g (8-bit, signed)
+ *
+ * scale = (1.5 + 1.5) * 9.81 / (2^8 - 1)	= 0.115411765
+ */
+
+#define MC3230_SCALE_AVAIL		"0.115411765"
+
+const int mc3230_nscale = 115411765;
+
+#define MC3230_CHANNEL(reg, axis) {	\
+	.type = IIO_ACCEL,	\
+	.address = reg,	\
+	.modified = 1,	\
+	.channel2 = IIO_MOD_##axis,	\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+}
+
+static const struct iio_chan_spec mc3230_channels[] = {
+	MC3230_CHANNEL(MC3230_REG_XOUT, X),
+	MC3230_CHANNEL(MC3230_REG_YOUT, Y),
+	MC3230_CHANNEL(MC3230_REG_ZOUT, Z),
+};
+
+struct mc3230_data {
+	struct i2c_client *client;
+};
+
+static IIO_CONST_ATTR(in_accel_scale_available, MC3230_SCALE_AVAIL);
+
+static struct attribute *mc3230_attributes[] = {
+	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group mc3230_attribute_group = {
+	.attrs = mc3230_attributes
+};
+
+static int mc3230_set_opcon(struct mc3230_data *data, int opcon)
+{
+	int ret;
+	struct i2c_client *client = data->client;
+
+	ret = i2c_smbus_read_byte_data(client, MC3230_REG_MODE);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed to read mode reg: %d\n", ret);
+		return ret;
+	}
+
+	ret &= ~MC3230_MODE_OPCON_MASK;
+	ret |= opcon;
+
+	ret = i2c_smbus_write_byte_data(client, MC3230_REG_MODE, ret);
+	if (ret < 0) {
+		dev_err(&client->dev, "failed to write mode reg: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int mc3230_read_raw(struct iio_dev *indio_dev,
+				struct iio_chan_spec const *chan,
+				int *val, int *val2, long mask)
+{
+	struct mc3230_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		ret = i2c_smbus_read_byte_data(data->client, chan->address);
+		if (ret < 0)
+			return ret;
+		*val = sign_extend32(ret, 7);
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 0;
+		*val2 = mc3230_nscale;
+		return IIO_VAL_INT_PLUS_NANO;
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_info mc3230_info = {
+	.driver_module	= THIS_MODULE,
+	.read_raw	= mc3230_read_raw,
+	.attrs		= &mc3230_attribute_group,
+};
+
+static int mc3230_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	int ret;
+	struct iio_dev *indio_dev;
+	struct mc3230_data *data;
+
+	/* First check chip-id and product-id */
+	ret = i2c_smbus_read_byte_data(client, MC3230_REG_CHIP_ID);
+	if (ret != MC3230_CHIP_ID)
+		return (ret < 0) ? ret : -ENODEV;
+
+	ret = i2c_smbus_read_byte_data(client, MC3230_REG_PRODUCT_CODE);
+	if (ret != MC3230_PRODUCT_CODE)
+		return (ret < 0) ? ret : -ENODEV;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev) {
+		dev_err(&client->dev, "iio allocation failed!\n");
+		return -ENOMEM;
+	}
+
+	data = iio_priv(indio_dev);
+	data->client = client;
+	i2c_set_clientdata(client, indio_dev);
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &mc3230_info;
+	indio_dev->name = "mc3230";
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = mc3230_channels;
+	indio_dev->num_channels = ARRAY_SIZE(mc3230_channels);
+
+	ret = mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
+	if (ret < 0)
+		return ret;
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0) {
+		dev_err(&client->dev, "device_register failed\n");
+		mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
+	}
+
+	return ret;
+}
+
+static int mc3230_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	iio_device_unregister(indio_dev);
+
+	return mc3230_set_opcon(iio_priv(indio_dev), MC3230_MODE_OPCON_STANDBY);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mc3230_suspend(struct device *dev)
+{
+	struct mc3230_data *data;
+
+	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
+
+	return mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
+}
+
+static int mc3230_resume(struct device *dev)
+{
+	struct mc3230_data *data;
+
+	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
+
+	return mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(mc3230_pm_ops, mc3230_suspend, mc3230_resume);
+
+static const struct i2c_device_id mc3230_i2c_id[] = {
+	{"mc3230", 0},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, mc3230_i2c_id);
+
+static struct i2c_driver mc3230_driver = {
+	.driver = {
+		.name = "mc3230",
+		.pm = &mc3230_pm_ops,
+	},
+	.probe		= mc3230_probe,
+	.remove		= mc3230_remove,
+	.id_table	= mc3230_i2c_id,
+};
+
+module_i2c_driver(mc3230_driver);
+
+MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
+MODULE_DESCRIPTION("mCube MC3230 3-Axis Accelerometer driver");
+MODULE_LICENSE("GPL v2");
-- 
2.9.3

Re: [PATCH] iio: accel: Add driver for the mCube MC3230 3-axis accelerometer

[Peter Meerwald-Stadler]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 8965 bytes --]


> Add an IIO driver for the mCube MC3230 3-axis accelerometer.

comments below
 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  .../devicetree/bindings/i2c/trivial-devices.txt    |   1 +
>  drivers/iio/accel/Kconfig                          |  10 +
>  drivers/iio/accel/Makefile                         |   1 +
>  drivers/iio/accel/mc3230.c                         | 225 +++++++++++++++++++++
>  4 files changed, 237 insertions(+)
>  create mode 100644 drivers/iio/accel/mc3230.c
> 
> diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> index badf5eb..fbbad64 100644
> --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
> @@ -56,6 +56,7 @@ maxim,ds1050		5 Bit Programmable, Pulse-Width Modulator
>  maxim,max1237		Low-Power, 4-/12-Channel, 2-Wire Serial, 12-Bit ADCs
>  maxim,max6625		9-Bit/12-Bit Temperature Sensors with I²C-Compatible Serial Interface
>  mc,rv3029c2		Real Time Clock Module with I2C-Bus
> +mcube,mc3230		mCube 3-axis 8-bit digital accelerometer
>  microchip,mcp4531-502	Microchip 7-bit Single I2C Digital Potentiometer (5k)
>  microchip,mcp4531-103	Microchip 7-bit Single I2C Digital Potentiometer (10k)
>  microchip,mcp4531-503	Microchip 7-bit Single I2C Digital Potentiometer (50k)
> diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> index 5630f23..3aee97d 100644
> --- a/drivers/iio/accel/Kconfig
> +++ b/drivers/iio/accel/Kconfig
> @@ -138,6 +138,16 @@ config KXCJK1013
>  	  To compile this driver as a module, choose M here: the module will
>  	  be called kxcjk-1013.
>  
> +config MC3230
> +	tristate "mCube MC3230 Digital Accelerometer Driver"
> +	depends on I2C
> +	help
> +	  Say yes here to build support for the mCube MC3230 low-g tri-axial
> +	  digital accelerometer.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called mc3230.
> +
>  config MMA7455
>  	tristate
>  	select IIO_BUFFER
> diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
> index e974841..07a0c72 100644
> --- a/drivers/iio/accel/Makefile
> +++ b/drivers/iio/accel/Makefile
> @@ -13,6 +13,7 @@ obj-$(CONFIG_DMARD09)	+= dmard09.o
>  obj-$(CONFIG_HID_SENSOR_ACCEL_3D) += hid-sensor-accel-3d.o
>  obj-$(CONFIG_KXCJK1013) += kxcjk-1013.o
>  obj-$(CONFIG_KXSD9)	+= kxsd9.o
> +obj-$(CONFIG_MC3230)	+= mc3230.o
>  
>  obj-$(CONFIG_MMA7455)		+= mma7455_core.o
>  obj-$(CONFIG_MMA7455_I2C)	+= mma7455_i2c.o
> diff --git a/drivers/iio/accel/mc3230.c b/drivers/iio/accel/mc3230.c
> new file mode 100644
> index 0000000..21127a9
> --- /dev/null
> +++ b/drivers/iio/accel/mc3230.c
> @@ -0,0 +1,225 @@
> +/**
> + * mCube MC3230 3-Axis Accelerometer
> + *
> + * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * IIO driver for mCube MC3230; 7-bit I2C address: 0x4c.
> + */
> +
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +
> +#define MC3230_REG_XOUT			0x00
> +#define MC3230_REG_YOUT			0x01
> +#define MC3230_REG_ZOUT			0x02
> +
> +#define MC3230_REG_MODE			0x07
> +#define MC3230_MODE_OPCON_MASK		0x03
> +#define MC3230_MODE_OPCON_WAKE		0x01
> +#define MC3230_MODE_OPCON_STANDBY	0x03
> +
> +#define MC3230_REG_CHIP_ID		0x18
> +#define MC3230_CHIP_ID			0x01
> +
> +#define MC3230_REG_PRODUCT_CODE		0x3b
> +#define MC3230_PRODUCT_CODE		0x19
> +
> +/*
> + * The accelerometer has one measurement range:
> + *
> + * -1.5g - +1.5g (8-bit, signed)
> + *
> + * scale = (1.5 + 1.5) * 9.81 / (2^8 - 1)	= 0.115411765
> + */
> +
> +#define MC3230_SCALE_AVAIL		"0.115411765"
> +
> +const int mc3230_nscale = 115411765;

static

> +
> +#define MC3230_CHANNEL(reg, axis) {	\
> +	.type = IIO_ACCEL,	\
> +	.address = reg,	\
> +	.modified = 1,	\
> +	.channel2 = IIO_MOD_##axis,	\
> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
> +	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
> +}
> +
> +static const struct iio_chan_spec mc3230_channels[] = {
> +	MC3230_CHANNEL(MC3230_REG_XOUT, X),
> +	MC3230_CHANNEL(MC3230_REG_YOUT, Y),
> +	MC3230_CHANNEL(MC3230_REG_ZOUT, Z),
> +};
> +
> +struct mc3230_data {
> +	struct i2c_client *client;
> +};
> +
> +static IIO_CONST_ATTR(in_accel_scale_available, MC3230_SCALE_AVAIL);
> +
> +static struct attribute *mc3230_attributes[] = {
> +	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group mc3230_attribute_group = {
> +	.attrs = mc3230_attributes
> +};
> +
> +static int mc3230_set_opcon(struct mc3230_data *data, int opcon)
> +{
> +	int ret;
> +	struct i2c_client *client = data->client;
> +

guess we want locking here

> +	ret = i2c_smbus_read_byte_data(client, MC3230_REG_MODE);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "failed to read mode reg: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret &= ~MC3230_MODE_OPCON_MASK;
> +	ret |= opcon;
> +
> +	ret = i2c_smbus_write_byte_data(client, MC3230_REG_MODE, ret);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "failed to write mode reg: %d\n", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int mc3230_read_raw(struct iio_dev *indio_dev,
> +				struct iio_chan_spec const *chan,
> +				int *val, int *val2, long mask)
> +{
> +	struct mc3230_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		ret = i2c_smbus_read_byte_data(data->client, chan->address);
> +		if (ret < 0)
> +			return ret;
> +		*val = sign_extend32(ret, 7);
> +		return IIO_VAL_INT;
> +	case IIO_CHAN_INFO_SCALE:
> +		*val = 0;
> +		*val2 = mc3230_nscale;
> +		return IIO_VAL_INT_PLUS_NANO;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static const struct iio_info mc3230_info = {
> +	.driver_module	= THIS_MODULE,
> +	.read_raw	= mc3230_read_raw,
> +	.attrs		= &mc3230_attribute_group,
> +};
> +
> +static int mc3230_probe(struct i2c_client *client,
> +			const struct i2c_device_id *id)
> +{
> +	int ret;
> +	struct iio_dev *indio_dev;
> +	struct mc3230_data *data;
> +
> +	/* First check chip-id and product-id */
> +	ret = i2c_smbus_read_byte_data(client, MC3230_REG_CHIP_ID);
> +	if (ret != MC3230_CHIP_ID)
> +		return (ret < 0) ? ret : -ENODEV;
> +
> +	ret = i2c_smbus_read_byte_data(client, MC3230_REG_PRODUCT_CODE);
> +	if (ret != MC3230_PRODUCT_CODE)
> +		return (ret < 0) ? ret : -ENODEV;
> +
> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> +	if (!indio_dev) {
> +		dev_err(&client->dev, "iio allocation failed!\n");
> +		return -ENOMEM;
> +	}
> +
> +	data = iio_priv(indio_dev);
> +	data->client = client;
> +	i2c_set_clientdata(client, indio_dev);
> +
> +	indio_dev->dev.parent = &client->dev;
> +	indio_dev->info = &mc3230_info;
> +	indio_dev->name = "mc3230";
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +	indio_dev->channels = mc3230_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(mc3230_channels);
> +
> +	ret = mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = iio_device_register(indio_dev);
> +	if (ret < 0) {
> +		dev_err(&client->dev, "device_register failed\n");
> +		mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
> +	}
> +
> +	return ret;
> +}
> +
> +static int mc3230_remove(struct i2c_client *client)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> +	iio_device_unregister(indio_dev);
> +
> +	return mc3230_set_opcon(iio_priv(indio_dev), MC3230_MODE_OPCON_STANDBY);
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int mc3230_suspend(struct device *dev)
> +{
> +	struct mc3230_data *data;
> +
> +	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
> +
> +	return mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
> +}
> +
> +static int mc3230_resume(struct device *dev)
> +{
> +	struct mc3230_data *data;
> +
> +	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
> +
> +	return mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
> +}
> +#endif
> +
> +static SIMPLE_DEV_PM_OPS(mc3230_pm_ops, mc3230_suspend, mc3230_resume);
> +
> +static const struct i2c_device_id mc3230_i2c_id[] = {
> +	{"mc3230", 0},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, mc3230_i2c_id);
> +
> +static struct i2c_driver mc3230_driver = {
> +	.driver = {
> +		.name = "mc3230",
> +		.pm = &mc3230_pm_ops,
> +	},
> +	.probe		= mc3230_probe,
> +	.remove		= mc3230_remove,
> +	.id_table	= mc3230_i2c_id,
> +};
> +
> +module_i2c_driver(mc3230_driver);
> +
> +MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
> +MODULE_DESCRIPTION("mCube MC3230 3-Axis Accelerometer driver");
> +MODULE_LICENSE("GPL v2");
> 

-- 

Peter Meerwald-Stadler
+43-664-2444418 (mobile)

Re: [PATCH] iio: accel: Add driver for the mCube MC3230 3-axis accelerometer

[Hans de Goede]

Hi,

On 11-09-16 19:47, Peter Meerwald-Stadler wrote:
>
>> Add an IIO driver for the mCube MC3230 3-axis accelerometer.
>
> comments below
>
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>> ---
>>  .../devicetree/bindings/i2c/trivial-devices.txt    |   1 +
>>  drivers/iio/accel/Kconfig                          |  10 +
>>  drivers/iio/accel/Makefile                         |   1 +
>>  drivers/iio/accel/mc3230.c                         | 225 +++++++++++++++++++++
>>  4 files changed, 237 insertions(+)
>>  create mode 100644 drivers/iio/accel/mc3230.c
>>
>> diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> index badf5eb..fbbad64 100644
>> --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
>> @@ -56,6 +56,7 @@ maxim,ds1050		5 Bit Programmable, Pulse-Width Modulator
>>  maxim,max1237		Low-Power, 4-/12-Channel, 2-Wire Serial, 12-Bit ADCs
>>  maxim,max6625		9-Bit/12-Bit Temperature Sensors with I²C-Compatible Serial Interface
>>  mc,rv3029c2		Real Time Clock Module with I2C-Bus
>> +mcube,mc3230		mCube 3-axis 8-bit digital accelerometer
>>  microchip,mcp4531-502	Microchip 7-bit Single I2C Digital Potentiometer (5k)
>>  microchip,mcp4531-103	Microchip 7-bit Single I2C Digital Potentiometer (10k)
>>  microchip,mcp4531-503	Microchip 7-bit Single I2C Digital Potentiometer (50k)
>> diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
>> index 5630f23..3aee97d 100644
>> --- a/drivers/iio/accel/Kconfig
>> +++ b/drivers/iio/accel/Kconfig
>> @@ -138,6 +138,16 @@ config KXCJK1013
>>  	  To compile this driver as a module, choose M here: the module will
>>  	  be called kxcjk-1013.
>>
>> +config MC3230
>> +	tristate "mCube MC3230 Digital Accelerometer Driver"
>> +	depends on I2C
>> +	help
>> +	  Say yes here to build support for the mCube MC3230 low-g tri-axial
>> +	  digital accelerometer.
>> +
>> +	  To compile this driver as a module, choose M here: the
>> +	  module will be called mc3230.
>> +
>>  config MMA7455
>>  	tristate
>>  	select IIO_BUFFER
>> diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
>> index e974841..07a0c72 100644
>> --- a/drivers/iio/accel/Makefile
>> +++ b/drivers/iio/accel/Makefile
>> @@ -13,6 +13,7 @@ obj-$(CONFIG_DMARD09)	+= dmard09.o
>>  obj-$(CONFIG_HID_SENSOR_ACCEL_3D) += hid-sensor-accel-3d.o
>>  obj-$(CONFIG_KXCJK1013) += kxcjk-1013.o
>>  obj-$(CONFIG_KXSD9)	+= kxsd9.o
>> +obj-$(CONFIG_MC3230)	+= mc3230.o
>>
>>  obj-$(CONFIG_MMA7455)		+= mma7455_core.o
>>  obj-$(CONFIG_MMA7455_I2C)	+= mma7455_i2c.o
>> diff --git a/drivers/iio/accel/mc3230.c b/drivers/iio/accel/mc3230.c
>> new file mode 100644
>> index 0000000..21127a9
>> --- /dev/null
>> +++ b/drivers/iio/accel/mc3230.c
>> @@ -0,0 +1,225 @@
>> +/**
>> + * mCube MC3230 3-Axis Accelerometer
>> + *
>> + * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation; either version 2 of the License, or
>> + * (at your option) any later version.
>> + *
>> + * IIO driver for mCube MC3230; 7-bit I2C address: 0x4c.
>> + */
>> +
>> +#include <linux/i2c.h>
>> +#include <linux/module.h>
>> +#include <linux/iio/iio.h>
>> +#include <linux/iio/sysfs.h>
>> +
>> +#define MC3230_REG_XOUT			0x00
>> +#define MC3230_REG_YOUT			0x01
>> +#define MC3230_REG_ZOUT			0x02
>> +
>> +#define MC3230_REG_MODE			0x07
>> +#define MC3230_MODE_OPCON_MASK		0x03
>> +#define MC3230_MODE_OPCON_WAKE		0x01
>> +#define MC3230_MODE_OPCON_STANDBY	0x03
>> +
>> +#define MC3230_REG_CHIP_ID		0x18
>> +#define MC3230_CHIP_ID			0x01
>> +
>> +#define MC3230_REG_PRODUCT_CODE		0x3b
>> +#define MC3230_PRODUCT_CODE		0x19
>> +
>> +/*
>> + * The accelerometer has one measurement range:
>> + *
>> + * -1.5g - +1.5g (8-bit, signed)
>> + *
>> + * scale = (1.5 + 1.5) * 9.81 / (2^8 - 1)	= 0.115411765
>> + */
>> +
>> +#define MC3230_SCALE_AVAIL		"0.115411765"
>> +
>> +const int mc3230_nscale = 115411765;
>
> static

Ack.

>> +
>> +#define MC3230_CHANNEL(reg, axis) {	\
>> +	.type = IIO_ACCEL,	\
>> +	.address = reg,	\
>> +	.modified = 1,	\
>> +	.channel2 = IIO_MOD_##axis,	\
>> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
>> +	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
>> +}
>> +
>> +static const struct iio_chan_spec mc3230_channels[] = {
>> +	MC3230_CHANNEL(MC3230_REG_XOUT, X),
>> +	MC3230_CHANNEL(MC3230_REG_YOUT, Y),
>> +	MC3230_CHANNEL(MC3230_REG_ZOUT, Z),
>> +};
>> +
>> +struct mc3230_data {
>> +	struct i2c_client *client;
>> +};
>> +
>> +static IIO_CONST_ATTR(in_accel_scale_available, MC3230_SCALE_AVAIL);
>> +
>> +static struct attribute *mc3230_attributes[] = {
>> +	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
>> +	NULL,
>> +};
>> +
>> +static const struct attribute_group mc3230_attribute_group = {
>> +	.attrs = mc3230_attributes
>> +};
>> +
>> +static int mc3230_set_opcon(struct mc3230_data *data, int opcon)
>> +{
>> +	int ret;
>> +	struct i2c_client *client = data->client;
>> +
>
> guess we want locking here

This register only gets touched by this function, and this
function only gets called:

-pre iio_device_register
-post iio_device_unregister
-on suspend/resume

So I do not see what it could race with.

Regards,

Hans




>
>> +	ret = i2c_smbus_read_byte_data(client, MC3230_REG_MODE);
>> +	if (ret < 0) {
>> +		dev_err(&client->dev, "failed to read mode reg: %d\n", ret);
>> +		return ret;
>> +	}
>> +
>> +	ret &= ~MC3230_MODE_OPCON_MASK;
>> +	ret |= opcon;
>> +
>> +	ret = i2c_smbus_write_byte_data(client, MC3230_REG_MODE, ret);
>> +	if (ret < 0) {
>> +		dev_err(&client->dev, "failed to write mode reg: %d\n", ret);
>> +		return ret;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int mc3230_read_raw(struct iio_dev *indio_dev,
>> +				struct iio_chan_spec const *chan,
>> +				int *val, int *val2, long mask)
>> +{
>> +	struct mc3230_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +
>> +	switch (mask) {
>> +	case IIO_CHAN_INFO_RAW:
>> +		ret = i2c_smbus_read_byte_data(data->client, chan->address);
>> +		if (ret < 0)
>> +			return ret;
>> +		*val = sign_extend32(ret, 7);
>> +		return IIO_VAL_INT;
>> +	case IIO_CHAN_INFO_SCALE:
>> +		*val = 0;
>> +		*val2 = mc3230_nscale;
>> +		return IIO_VAL_INT_PLUS_NANO;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +}
>> +
>> +static const struct iio_info mc3230_info = {
>> +	.driver_module	= THIS_MODULE,
>> +	.read_raw	= mc3230_read_raw,
>> +	.attrs		= &mc3230_attribute_group,
>> +};
>> +
>> +static int mc3230_probe(struct i2c_client *client,
>> +			const struct i2c_device_id *id)
>> +{
>> +	int ret;
>> +	struct iio_dev *indio_dev;
>> +	struct mc3230_data *data;
>> +
>> +	/* First check chip-id and product-id */
>> +	ret = i2c_smbus_read_byte_data(client, MC3230_REG_CHIP_ID);
>> +	if (ret != MC3230_CHIP_ID)
>> +		return (ret < 0) ? ret : -ENODEV;
>> +
>> +	ret = i2c_smbus_read_byte_data(client, MC3230_REG_PRODUCT_CODE);
>> +	if (ret != MC3230_PRODUCT_CODE)
>> +		return (ret < 0) ? ret : -ENODEV;
>> +
>> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
>> +	if (!indio_dev) {
>> +		dev_err(&client->dev, "iio allocation failed!\n");
>> +		return -ENOMEM;
>> +	}
>> +
>> +	data = iio_priv(indio_dev);
>> +	data->client = client;
>> +	i2c_set_clientdata(client, indio_dev);
>> +
>> +	indio_dev->dev.parent = &client->dev;
>> +	indio_dev->info = &mc3230_info;
>> +	indio_dev->name = "mc3230";
>> +	indio_dev->modes = INDIO_DIRECT_MODE;
>> +	indio_dev->channels = mc3230_channels;
>> +	indio_dev->num_channels = ARRAY_SIZE(mc3230_channels);
>> +
>> +	ret = mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	ret = iio_device_register(indio_dev);
>> +	if (ret < 0) {
>> +		dev_err(&client->dev, "device_register failed\n");
>> +		mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
>> +	}
>> +
>> +	return ret;
>> +}
>> +
>> +static int mc3230_remove(struct i2c_client *client)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
>> +
>> +	iio_device_unregister(indio_dev);
>> +
>> +	return mc3230_set_opcon(iio_priv(indio_dev), MC3230_MODE_OPCON_STANDBY);
>> +}
>> +
>> +#ifdef CONFIG_PM_SLEEP
>> +static int mc3230_suspend(struct device *dev)
>> +{
>> +	struct mc3230_data *data;
>> +
>> +	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
>> +
>> +	return mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
>> +}
>> +
>> +static int mc3230_resume(struct device *dev)
>> +{
>> +	struct mc3230_data *data;
>> +
>> +	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
>> +
>> +	return mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
>> +}
>> +#endif
>> +
>> +static SIMPLE_DEV_PM_OPS(mc3230_pm_ops, mc3230_suspend, mc3230_resume);
>> +
>> +static const struct i2c_device_id mc3230_i2c_id[] = {
>> +	{"mc3230", 0},
>> +	{}
>> +};
>> +MODULE_DEVICE_TABLE(i2c, mc3230_i2c_id);
>> +
>> +static struct i2c_driver mc3230_driver = {
>> +	.driver = {
>> +		.name = "mc3230",
>> +		.pm = &mc3230_pm_ops,
>> +	},
>> +	.probe		= mc3230_probe,
>> +	.remove		= mc3230_remove,
>> +	.id_table	= mc3230_i2c_id,
>> +};
>> +
>> +module_i2c_driver(mc3230_driver);
>> +
>> +MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
>> +MODULE_DESCRIPTION("mCube MC3230 3-Axis Accelerometer driver");
>> +MODULE_LICENSE("GPL v2");
>>
>

Re: [PATCH] iio: accel: Add driver for the mCube MC3230 3-axis accelerometer

[Hans de Goede]

Hi,

On 11-09-16 20:59, Hans de Goede wrote:
> Hi,
>
> On 11-09-16 19:47, Peter Meerwald-Stadler wrote:
>>
>>> Add an IIO driver for the mCube MC3230 3-axis accelerometer.
>>
>> comments below

p.s.

Thank you for the quick review.

Regards,

Hans

Re: [PATCH] iio: accel: Add driver for the mCube MC3230 3-axis accelerometer

[Peter Meerwald-Stadler]

> > > +static const struct iio_chan_spec mc3230_channels[] = {
> > > +	MC3230_CHANNEL(MC3230_REG_XOUT, X),
> > > +	MC3230_CHANNEL(MC3230_REG_YOUT, Y),
> > > +	MC3230_CHANNEL(MC3230_REG_ZOUT, Z),
> > > +};
> > > +
> > > +struct mc3230_data {
> > > +	struct i2c_client *client;
> > > +};

probably don't need mc3230_data (or the client pointer within), not worth 
changing as likely stuff will be added in the future

> > > +static int mc3230_set_opcon(struct mc3230_data *data, int opcon)
> > > +{
> > > +	int ret;
> > > +	struct i2c_client *client = data->client;
> > > +
> > 
> > guess we want locking here
> 
> This register only gets touched by this function, and this
> function only gets called:
> 
> -pre iio_device_register
> -post iio_device_unregister
> -on suspend/resume

> So I do not see what it could race with.

I didn't check where set_opcon() is actually called, seems safe

I think there is a theoretic race in _remove() as _unregister() retval is 
not checked, no need to change

p.

-- 

Peter Meerwald-Stadler
+43-664-2444418 (mobile)

Re: [PATCH] iio: accel: Add driver for the mCube MC3230 3-axis accelerometer

[Hans de Goede]

Hi,

On 12-09-16 07:32, Peter Meerwald-Stadler wrote:
>
>>>> +static const struct iio_chan_spec mc3230_channels[] = {
>>>> +	MC3230_CHANNEL(MC3230_REG_XOUT, X),
>>>> +	MC3230_CHANNEL(MC3230_REG_YOUT, Y),
>>>> +	MC3230_CHANNEL(MC3230_REG_ZOUT, Z),
>>>> +};
>>>> +
>>>> +struct mc3230_data {
>>>> +	struct i2c_client *client;
>>>> +};
>
> probably don't need mc3230_data (or the client pointer within), not worth
> changing as likely stuff will be added in the future

I was thinking the same, but since iio does not use
set / get private_data but instead allocs private data
as part of devm_iio_device_alloc, this seemed cleaner then doing:

devm_iio_device_alloc(&client->dev, sizeof(struct i2c_client *));

And then doing somewhat ugly casts to retrieve the client pointer again.

>>>> +static int mc3230_set_opcon(struct mc3230_data *data, int opcon)
>>>> +{
>>>> +	int ret;
>>>> +	struct i2c_client *client = data->client;
>>>> +
>>>
>>> guess we want locking here
>>
>> This register only gets touched by this function, and this
>> function only gets called:
>>
>> -pre iio_device_register
>> -post iio_device_unregister
>> -on suspend/resume
>
>> So I do not see what it could race with.
>
> I didn't check where set_opcon() is actually called, seems safe
>
> I think there is a theoretic race in _remove() as _unregister() retval is
> not checked, no need to change

OK, I'll do a v2 adding the missing static then.

Regards,

Hans

Re: [PATCH] iio: accel: Add driver for the mCube MC3230 3-axis accelerometer

[Daniel Baluta]

On Sun, Sep 11, 2016 at 7:29 PM, Hans de Goede <hdegoede@redhat.com> wrote:
> Add an IIO driver for the mCube MC3230 3-axis accelerometer.

Hi Hans,

This looks good. Could you add a link to documentation in the commit message?