From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751636AbbJSLIx (ORCPT ); Mon, 19 Oct 2015 07:08:53 -0400 Received: from ns.pmeerw.net ([84.19.176.92]:55815 "EHLO pmeerw.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750784AbbJSLIv (ORCPT ); Mon, 19 Oct 2015 07:08:51 -0400 Date: Mon, 19 Oct 2015 13:08:50 +0200 (CEST) From: Peter Meerwald To: Teodora Baluta cc: jic23@kernel.org, knaack.h@gmx.de, lars@metafoo.de, daniel.baluta@intel.com, dan.carpenter@oracle.com, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] iio: accel: add support for Memsic MXC6255XC sensor In-Reply-To: <1444991368-14609-1-git-send-email-teodora.baluta@intel.com> Message-ID: References: <1444991368-14609-1-git-send-email-teodora.baluta@intel.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 16 Oct 2015, Teodora Baluta wrote: > This patch adds a minimal implementation for the Memsic MXC6255XC > orientation sensing accelerometer. The supported operations are reading > raw acceleration values for X/Y axis that can be scaled using the > exposed scale. minor comments below link to datasheet? > Signed-off-by: Teodora Baluta > --- > drivers/iio/accel/Kconfig | 11 +++ > drivers/iio/accel/Makefile | 1 + > drivers/iio/accel/mxc6255.c | 210 ++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 222 insertions(+) > create mode 100644 drivers/iio/accel/mxc6255.c > > diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig > index 969428d..75ac087 100644 > --- a/drivers/iio/accel/Kconfig > +++ b/drivers/iio/accel/Kconfig > @@ -158,6 +158,17 @@ config MXC4005 > To compile this driver as a module, choose M. The module will be > called mxc4005. > > +config MXC6255 > + tristate "Memsic MXC6255 Orientation Sensing Accelerometer Driver" > + depends on I2C > + select REGMAP_I2C > + help > + Say yes here to build support for the Memsic MXC6255 Orientation > + Sensing Accelerometer Driver. > + > + To compile this driver as a module, choose M here: the module will be > + called mxc6255. > + > config STK8312 > tristate "Sensortek STK8312 3-Axis Accelerometer Driver" > depends on I2C > diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile > index 7925f16..525ed52 100644 > --- a/drivers/iio/accel/Makefile > +++ b/drivers/iio/accel/Makefile > @@ -17,6 +17,7 @@ obj-$(CONFIG_MMA9551) += mma9551.o > obj-$(CONFIG_MMA9553) += mma9553.o > > obj-$(CONFIG_MXC4005) += mxc4005.o > +obj-$(CONFIG_MXC6255) += mxc6255.o > > obj-$(CONFIG_STK8312) += stk8312.o > obj-$(CONFIG_STK8BA50) += stk8ba50.o > diff --git a/drivers/iio/accel/mxc6255.c b/drivers/iio/accel/mxc6255.c > new file mode 100644 > index 0000000..ed0f1ab > --- /dev/null > +++ b/drivers/iio/accel/mxc6255.c > @@ -0,0 +1,210 @@ > +/* > + * MXC6255 - MEMSIC orientation sensing accelerometer > + * > + * Copyright (c) 2015, Intel Corporation. > + * > + * 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. > + * > + * IIO driver for MXC6255 (7-bit I2C slave address 0x15). > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define MXC6255_DRV_NAME "mxc6255" > +#define MXC6255_REGMAP_NAME "mxc6255_regmap" > + > +#define MXC6255_REG_XOUT 0x00 > +#define MXC6255_REG_YOUT 0x01 > +#define MXC6255_REG_CHIP_ID 0x08 > + > +#define MXC6255_AXIS_TO_REG(axis) (MXC6255_REG_XOUT + axis) > + > +/* > + * MXC6255 has only one measurement range: +/- 2G. > + * The acceleration output is an 8-bit value. is a > + * > + * Scale is calculated as following: as follows > + * (2 + 2) * 9.80665 / (2^8 - 1) = 0.153829 > + * > + */ > +#define MXC6255_SCALE_AVAIL "0.153829" > + > +enum mxc6255_axis { > + AXIS_X, > + AXIS_Y, > +}; > + > +struct mxc6255_data { > + struct i2c_client *client; > + struct regmap *regmap; > +}; > + > +/* scale value for +/- 2G measurement range */ > +static const int mxc6255_scale = 153829; it is customary to use a #define > + > +static IIO_CONST_ATTR(in_accel_scale_available, MXC6255_SCALE_AVAIL); > + > +static struct attribute *mxc6255_attributes[] = { > + &iio_const_attr_in_accel_scale_available.dev_attr.attr, > + NULL, > +}; > + > +static const struct attribute_group mxc6255_attribute_group = { > + .attrs = mxc6255_attributes > +}; > + > +static int mxc6255_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long mask) > +{ > + struct mxc6255_data *data = iio_priv(indio_dev); > + unsigned int reg; > + int axis = chan->channel2 - 1; > + int ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + ret = regmap_read(data->regmap, > + MXC6255_AXIS_TO_REG(axis), ®); use chan->address, and drop the _AXIS_TO_REG macro and axis variable > + if (ret < 0) { > + dev_err(&data->client->dev, > + "Error reading axis %d\n", axis); > + return ret; > + } > + > + *val = sign_extend32(reg, 7); > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_SCALE: > + *val = 0; > + *val2 = mxc6255_scale; > + return IIO_VAL_INT_PLUS_MICRO; > + default: > + return -EINVAL; > + } > +} > + > +static const struct iio_info mxc6255_info = { > + .driver_module = THIS_MODULE, > + .read_raw = mxc6255_read_raw, > + .attrs = &mxc6255_attribute_group, > +}; > + > +#define MXC6255_CHANNEL(_axis) { \ > + .type = IIO_ACCEL, \ > + .modified = 1, \ > + .channel2 = IIO_MOD_##_axis, \ > + .address = AXIS_##_axis, \ put MXC6255_REG_XOUT / MXC6255_REG_YOUT here, add parameter to _CHANNEL macro > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ > +} > + > +static const struct iio_chan_spec mxc6255_channels[] = { > + MXC6255_CHANNEL(X), > + MXC6255_CHANNEL(Y), > +}; > + > +static bool mxc6255_is_readable_reg(struct device *dev, unsigned int reg) > +{ > + switch (reg) { > + case MXC6255_REG_XOUT: > + case MXC6255_REG_YOUT: > + case MXC6255_REG_CHIP_ID: > + return true; > + default: > + return false; > + } > +} > + > +static const struct regmap_config mxc6255_regmap_config = { > + .name = MXC6255_REGMAP_NAME, > + > + .reg_bits = 8, > + .val_bits = 8, > + > + .readable_reg = mxc6255_is_readable_reg, > +}; > + > +static int mxc6255_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct mxc6255_data *data; > + struct iio_dev *indio_dev; > + struct regmap *regmap; > + unsigned int chip_id; > + int ret; > + > + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); > + if (!indio_dev) > + return -ENOMEM; > + > + regmap = devm_regmap_init_i2c(client, &mxc6255_regmap_config); > + if (IS_ERR(regmap)) { > + dev_err(&client->dev, "Error initializing regmap\n"); > + return PTR_ERR(regmap); > + } > + > + data = iio_priv(indio_dev); > + i2c_set_clientdata(client, indio_dev); > + data->client = client; > + data->regmap = regmap; > + > + indio_dev->name = MXC6255_DRV_NAME; > + indio_dev->dev.parent = &client->dev; > + indio_dev->channels = mxc6255_channels; > + indio_dev->num_channels = ARRAY_SIZE(mxc6255_channels); > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->info = &mxc6255_info; > + > + ret = regmap_read(data->regmap, MXC6255_REG_CHIP_ID, &chip_id); > + if (ret < 0) { > + dev_err(&client->dev, "Error reading chip id %d\n", ret); > + return ret; > + } > + > + dev_dbg(&client->dev, "Chip id %x\n", chip_id); maybe check chip id? > + > + ret = devm_iio_device_register(&client->dev, indio_dev); > + if (ret < 0) { > + dev_err(&client->dev, "Could not register IIO device\n"); > + return ret; > + } > + > + return 0; > +} > + > +static const struct acpi_device_id mxc6255_acpi_match[] = { > + {"MXC6255", 0}, > + { } > +}; > +MODULE_DEVICE_TABLE(acpi, mxc6255_acpi_match); > + > +static const struct i2c_device_id mxc6255_id[] = { > + {"mxc6255", 0}, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, mxc6255_id); > + > +static struct i2c_driver mxc6255_driver = { > + .driver = { > + .name = MXC6255_DRV_NAME, > + .acpi_match_table = ACPI_PTR(mxc6255_acpi_match), > + }, > + .probe = mxc6255_probe, > + .id_table = mxc6255_id, > +}; > + > +module_i2c_driver(mxc6255_driver); > + > +MODULE_AUTHOR("Teodora Baluta "); > +MODULE_DESCRIPTION("MEMSIC MXC6255 orientation sensing accelerometer driver"); > +MODULE_LICENSE("GPL v2"); > -- Peter Meerwald +43-664-2444418 (mobile)