Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753308AbcD2NIJ (ORCPT ); Fri, 29 Apr 2016 09:08:09 -0400 Received: from mout01.posteo.de ([185.67.36.65]:48461 "EHLO mout01.posteo.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753409AbcD2NIG (ORCPT ); Fri, 29 Apr 2016 09:08:06 -0400 Subject: Re: [PATCH v3] iio: accel: Add support for Freescale MMA7660FC To: Constantin Musca , jic23@kernel.org, knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org References: <1461932343-14967-1-git-send-email-constantin.musca@intel.com> Cc: daniel.baluta@intel.com From: Martin Kepplinger X-Enigmail-Draft-Status: N1110 Message-ID: <57235CB0.40803@posteo.de> Date: Fri, 29 Apr 2016 15:08:00 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Icedove/38.7.0 MIME-Version: 1.0 In-Reply-To: <1461932343-14967-1-git-send-email-constantin.musca@intel.com> Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9555 Lines: 341 Am 2016-04-29 um 14:19 schrieb Constantin Musca: > Minimal implementation of an IIO driver for the Freescale > MMA7660FC 3-axis accelerometer. Datasheet: > http://www.freescale.com.cn/files/sensors/doc/data_sheet/MMA7660FC.pdf it's nxp.com now, which would probably be valid for a longer time. Theoretically there would be a way to add it to mma8452, but with quite some rewriting of register definitions. I guess it's ok to start over here to keep it simple. If everyone is aware of this, feel free to add my reviewed-by. Are you planning to support it's orienation detection via iio in the future? martin > > Includes: > - ACPI support; > - read_raw for x,y,z axes; > - reading and setting the scale (range) parameter. > - power management > > Signed-off-by: Constantin Musca > --- > drivers/iio/accel/Kconfig | 10 ++ > drivers/iio/accel/Makefile | 2 + > drivers/iio/accel/mma7660.c | 269 ++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 281 insertions(+) > create mode 100644 drivers/iio/accel/mma7660.c > > diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig > index e4a758c..1df6361 100644 > --- a/drivers/iio/accel/Kconfig > +++ b/drivers/iio/accel/Kconfig > @@ -136,6 +136,16 @@ config MMA7455_SPI > To compile this driver as a module, choose M here: the module > will be called mma7455_spi. > > +config MMA7660 > + tristate "Freescale MMA7660FC 3-Axis Accelerometer Driver" > + depends on I2C > + help > + Say yes here to get support for the Freescale MMA7660FC 3-Axis > + accelerometer. > + > + Choosing M will build the driver as a module. If so, the module > + will be called mma7660. > + > config MMA8452 > tristate "Freescale MMA8452Q and similar Accelerometers Driver" > depends on I2C > diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile > index 71b6794..ba1165f 100644 > --- a/drivers/iio/accel/Makefile > +++ b/drivers/iio/accel/Makefile > @@ -15,6 +15,8 @@ obj-$(CONFIG_MMA7455) += mma7455_core.o > obj-$(CONFIG_MMA7455_I2C) += mma7455_i2c.o > obj-$(CONFIG_MMA7455_SPI) += mma7455_spi.o > > +obj-$(CONFIG_MMA7660) += mma7660.o > + > obj-$(CONFIG_MMA8452) += mma8452.o > > obj-$(CONFIG_MMA9551_CORE) += mma9551_core.o > diff --git a/drivers/iio/accel/mma7660.c b/drivers/iio/accel/mma7660.c > new file mode 100644 > index 0000000..94b2999 > --- /dev/null > +++ b/drivers/iio/accel/mma7660.c > @@ -0,0 +1,269 @@ > +/** > + * Freescale MMA7660FC 3-Axis Accelerometer > + * > + * Copyright (c) 2016, 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 Freescale MMA7660FC; 7-bit I2C address: 0x4c. > + */ > + > +#include > +#include > +#include > +#include > +#include > + > +#define MMA7660_DRIVER_NAME "mma7660" > + > +#define MMA7660_REG_XOUT 0x00 > +#define MMA7660_REG_YOUT 0x01 > +#define MMA7660_REG_ZOUT 0x02 > +#define MMA7660_REG_OUT_BIT_ALERT BIT(6) > + > +#define MMA7660_REG_MODE 0x07 > +#define MMA7660_REG_MODE_BIT_MODE BIT(0) > +#define MMA7660_REG_MODE_BIT_TON BIT(2) > + > +#define MMA7660_I2C_READ_RETRIES 5 > + > +/* > + * The accelerometer has one measurement range: > + * > + * -1.5g - +1.5g (6-bit, signed) > + * > + * scale = (1.5 + 1.5) * 9.81 / (2^6 - 1) = 0.467142857 > + */ > + > +#define MMA7660_SCALE_AVAIL "0.467142857" > + > +const int mma7660_nscale = 467142857; > + > +#define MMA7660_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 mma7660_channels[] = { > + MMA7660_CHANNEL(MMA7660_REG_XOUT, X), > + MMA7660_CHANNEL(MMA7660_REG_YOUT, Y), > + MMA7660_CHANNEL(MMA7660_REG_ZOUT, Z), > +}; > + > +enum mma7660_mode { > + MMA7660_MODE_STANDBY, > + MMA7660_MODE_ACTIVE > +}; > + > +struct mma7660_data { > + struct i2c_client *client; > + struct mutex lock; > + enum mma7660_mode mode; > +}; > + > +static IIO_CONST_ATTR(in_accel_scale_available, MMA7660_SCALE_AVAIL); > + > +static struct attribute *mma7660_attributes[] = { > + &iio_const_attr_in_accel_scale_available.dev_attr.attr, > + NULL, > +}; > + > +static const struct attribute_group mma7660_attribute_group = { > + .attrs = mma7660_attributes > +}; > + > +static int mma7660_set_mode(struct mma7660_data *data, > + enum mma7660_mode mode) > +{ > + int ret; > + struct i2c_client *client = data->client; > + > + if (mode == data->mode) > + return 0; > + > + ret = i2c_smbus_read_byte_data(client, MMA7660_REG_MODE); > + if (ret < 0) { > + dev_err(&client->dev, "failed to read sensor mode\n"); > + return ret; > + } > + > + if (mode == MMA7660_MODE_ACTIVE) { > + ret &= ~MMA7660_REG_MODE_BIT_TON; > + ret |= MMA7660_REG_MODE_BIT_MODE; > + } else { > + ret &= ~MMA7660_REG_MODE_BIT_TON; > + ret &= ~MMA7660_REG_MODE_BIT_MODE; > + } > + > + ret = i2c_smbus_write_byte_data(client, MMA7660_REG_MODE, ret); > + if (ret < 0) { > + dev_err(&client->dev, "failed to change sensor mode\n"); > + return ret; > + } > + > + data->mode = mode; > + return ret; > +} > + > +static int mma7660_read_accel(struct mma7660_data *data, u8 address) > +{ > + int ret, retries = MMA7660_I2C_READ_RETRIES; > + struct i2c_client *client = data->client; > + > + do { > + ret = i2c_smbus_read_byte_data(client, address); > + if (ret < 0) { > + dev_err(&client->dev, "register read failed\n"); > + return ret; > + } > + } while (retries-- > 0 && ret & MMA7660_REG_OUT_BIT_ALERT); > + > + if (ret & MMA7660_REG_OUT_BIT_ALERT) { > + dev_err(&client->dev, "all register read retries failed\n"); > + return -ETIMEDOUT; > + } > + > + return ret; > +} > + > +static int mma7660_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + int *val, int *val2, long mask) > +{ > + struct mma7660_data *data = iio_priv(indio_dev); > + int ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + mutex_lock(&data->lock); > + ret = mma7660_read_accel(data, chan->address); > + mutex_unlock(&data->lock); > + if (ret < 0) > + return ret; > + *val = sign_extend32(ret, 5); > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_SCALE: > + *val = 0; > + *val2 = mma7660_nscale; > + return IIO_VAL_INT_PLUS_NANO; > + default: > + return -EINVAL; > + } > + > + return -EINVAL; > +} > + > +static const struct iio_info mma7660_info = { > + .driver_module = THIS_MODULE, > + .read_raw = mma7660_read_raw, > + .attrs = &mma7660_attribute_group, > +}; > + > +static int mma7660_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + int ret; > + struct iio_dev *indio_dev; > + struct mma7660_data *data; > + > + 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); > + mutex_init(&data->lock); > + data->mode = MMA7660_MODE_STANDBY; > + > + indio_dev->dev.parent = &client->dev; > + indio_dev->info = &mma7660_info; > + indio_dev->name = MMA7660_DRIVER_NAME; > + indio_dev->modes = INDIO_DIRECT_MODE; > + indio_dev->channels = mma7660_channels; > + indio_dev->num_channels = ARRAY_SIZE(mma7660_channels); > + > + ret = mma7660_set_mode(data, MMA7660_MODE_ACTIVE); > + if (ret < 0) > + return ret; > + > + ret = iio_device_register(indio_dev); > + if (ret < 0) { > + dev_err(&client->dev, "device_register failed\n"); > + mma7660_set_mode(data, MMA7660_MODE_STANDBY); > + } > + > + return ret; > +} > + > +static int mma7660_remove(struct i2c_client *client) > +{ > + struct iio_dev *indio_dev = i2c_get_clientdata(client); > + > + iio_device_unregister(indio_dev); > + > + return mma7660_set_mode(iio_priv(indio_dev), MMA7660_MODE_STANDBY); > +} > + > +#ifdef CONFIG_PM_SLEEP > +static int mma7660_suspend(struct device *dev) > +{ > + struct mma7660_data *data; > + > + data = iio_priv(i2c_get_clientdata(to_i2c_client(dev))); > + > + return mma7660_set_mode(data, MMA7660_MODE_STANDBY); > +} > + > +static int mma7660_resume(struct device *dev) > +{ > + struct mma7660_data *data; > + > + data = iio_priv(i2c_get_clientdata(to_i2c_client(dev))); > + > + return mma7660_set_mode(data, MMA7660_MODE_ACTIVE); > +} > + > +static SIMPLE_DEV_PM_OPS(mma7660_pm_ops, mma7660_suspend, mma7660_resume); > + > +#define MMA7660_PM_OPS (&mma7660_pm_ops) > +#else > +#define MMA7660_PM_OPS NULL > +#endif > + > +static const struct i2c_device_id mma7660_i2c_id[] = { > + {"mma7660", 0}, > + {} > +}; > + > +static const struct acpi_device_id mma7660_acpi_id[] = { > + {"MMA7660", 0}, > + {} > +}; > + > +MODULE_DEVICE_TABLE(acpi, mma7660_acpi_id); > + > +static struct i2c_driver mma7660_driver = { > + .driver = { > + .name = "mma7660", > + .pm = MMA7660_PM_OPS, > + .acpi_match_table = ACPI_PTR(mma7660_acpi_id), > + }, > + .probe = mma7660_probe, > + .remove = mma7660_remove, > + .id_table = mma7660_i2c_id, > +}; > + > +module_i2c_driver(mma7660_driver); > + > +MODULE_AUTHOR("Constantin Musca "); > +MODULE_DESCRIPTION("Freescale MMA7660FC 3-Axis Accelerometer driver"); > +MODULE_LICENSE("GPL v2"); >