Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750944AbaKPVKs (ORCPT ); Sun, 16 Nov 2014 16:10:48 -0500 Received: from saturn.retrosnub.co.uk ([178.18.118.26]:52356 "EHLO saturn.retrosnub.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750738AbaKPVKq (ORCPT ); Sun, 16 Nov 2014 16:10:46 -0500 Message-ID: <546912D3.1030602@kernel.org> Date: Sun, 16 Nov 2014 21:10:43 +0000 From: Jonathan Cameron User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: Daniel Baluta CC: linux-iio@vger.kernel.org, srinivas.pandruvada@linux.intel.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] iio: imu: Add support for Kionix KMX61 sensor References: <1415640251-2047-1-git-send-email-daniel.baluta@intel.com> In-Reply-To: <1415640251-2047-1-git-send-email-daniel.baluta@intel.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/11/14 17:24, Daniel Baluta wrote: > Minimal implementation for KMX61 6-axis accelerometer/magnetometer. It exports > raw accel/magn readings together with scale and sampling frequency. > > Datasheet will be available at: > http://www.kionix.com/6-axis-accelerometer-magnetometer/kmx61 > > Signed-off-by: Daniel Baluta Looking very nice. I made a few more comments inline but only one was more than a comment - I added a check on val==0 in the obvious place. Please take a look at the testing branch of iio.git to make sure I didn't mess anything up! Applied to the togreg branch of iio.git - initially pushed out as testing for the autobuilders to play with it. Jonathan > --- > Changes since v1: > * serialize non-atomic operations with a mutex (set_odr/get_odr, set_scale). > * no need to protect reading info scale because it reduces to reading an u8 > which should be atomic on all arches > * *note* - read_measurment is an atomic operation > > drivers/iio/imu/Kconfig | 9 + > drivers/iio/imu/Makefile | 2 + > drivers/iio/imu/kmx61.c | 590 +++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 601 insertions(+) > create mode 100644 drivers/iio/imu/kmx61.c > > diff --git a/drivers/iio/imu/Kconfig b/drivers/iio/imu/Kconfig > index 2b0e451..d675f43 100644 > --- a/drivers/iio/imu/Kconfig > +++ b/drivers/iio/imu/Kconfig > @@ -25,6 +25,15 @@ config ADIS16480 > Say yes here to build support for Analog Devices ADIS16375, ADIS16480, > ADIS16485, ADIS16488 inertial sensors. > > +config KMX61 > + tristate "Kionix KMX61 6-axis accelerometer and magnetometer" > + depends on I2C > + help > + Say Y here if you want to build a driver for Kionix KMX61 6-axis accelerometer > + and magnetometer. > + To compile this driver as module, choose M here: the module will be called > + kmx61. > + > source "drivers/iio/imu/inv_mpu6050/Kconfig" > > endmenu > diff --git a/drivers/iio/imu/Makefile b/drivers/iio/imu/Makefile > index 114d2c1..e1e6e3d 100644 > --- a/drivers/iio/imu/Makefile > +++ b/drivers/iio/imu/Makefile > @@ -14,3 +14,5 @@ adis_lib-$(CONFIG_IIO_ADIS_LIB_BUFFER) += adis_buffer.o > obj-$(CONFIG_IIO_ADIS_LIB) += adis_lib.o > > obj-y += inv_mpu6050/ > + > +obj-$(CONFIG_KMX61) += kmx61.o > diff --git a/drivers/iio/imu/kmx61.c b/drivers/iio/imu/kmx61.c > new file mode 100644 > index 0000000..6135a16 > --- /dev/null > +++ b/drivers/iio/imu/kmx61.c > @@ -0,0 +1,590 @@ > +/* > + * KMX61 - Kionix 6-axis Accelerometer/Magnetometer > + * > + * Copyright (c) 2014, 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 KMX61 (7-bit I2C slave address 0x0E or 0x0F). > + * > + * TODO: buffer, interrupt, thresholds, acpi, temperature sensor > + * > + */ > + > +#include > +#include > +#include > +#include > + > +#define KMX61_DRV_NAME "kmx61" > + > +#define KMX61_REG_WHO_AM_I 0x00 > + > +#define KMX61_ACC_XOUT_L 0x0A > + > +#define KMX61_ACC_XOUT_H 0x0B > +#define KMX61_ACC_YOUT_L 0x0C > +#define KMX61_ACC_YOUT_H 0x0D > +#define KMX61_ACC_ZOUT_L 0x0E > +#define KMX61_ACC_ZOUT_H 0x0F > + > +#define KMX61_MAG_XOUT_L 0x12 > + > +#define KMX61_MAG_XOUT_H 0x13 > +#define KMX61_MAG_YOUT_L 0x14 > +#define KMX61_MAG_YOUT_H 0x15 > +#define KMX61_MAG_ZOUT_L 0x16 > +#define KMX61_MAG_ZOUT_H 0x17 > + > +#define KMX61_REG_ODCNTL 0x2C > + > +#define KMX61_REG_STBY 0x29 > +#define KMX61_REG_CTRL1 0x2A > + > +#define KMX61_REG_COTR 0x3C > + > +#define KMX61_ACC_STBY_BIT BIT(0) > +#define KMX61_MAG_STBY_BIT BIT(1) > +#define KMX61_ACT_STBY_BIT BIT(7) > + > +#define KMX61_ALL_STBY (KMX61_ACC_STBY_BIT | KMX61_MAG_STBY_BIT) > + > +#define KMX61_REG_CTRL1_GSEL0_SHIFT 0 > +#define KMX61_REG_CTRL1_GSEL1_SHIFT 1 > +#define KMX61_REG_CTRL1_GSEL0_MASK 0x01 > +#define KMX61_REG_CTRL1_GSEL1_MASK 0x02 > + > +#define KMX61_REG_CTRL1_BIT_RES BIT(4) > + > +#define KMX61_ACC_ODR_SHIFT 0 > +#define KMX61_MAG_ODR_SHIFT 4 > +#define KMX61_ACC_ODR_MASK 0x0F > +#define KMX61_MAG_ODR_MASK 0xF0 > + > +#define KMX61_CHIP_ID 0x12 > + > +struct kmx61_data { > + struct i2c_client *client; > + /* serialize access to non-atomic ops, e.g set_mode */ > + struct mutex lock; > + u8 range; > + u8 odr_bits; > +}; > + > +enum kmx61_range { > + KMX61_RANGE_2G, > + KMX61_RANGE_4G, > + KMX61_RANGE_8G, > +}; > + > +enum kmx61_scan { > + KMX61_SCAN_ACC_X, > + KMX61_SCAN_ACC_Y, > + KMX61_SCAN_ACC_Z, > + KMX61_SCAN_TEMP, > + KMX61_SCAN_MAG_X, > + KMX61_SCAN_MAG_Y, > + KMX61_SCAN_MAG_Z, > +}; > + > +static const struct { > + u16 scale; > + u8 gsel0; > + u8 gsel1; > +} kmx61_scale_table[] = { > + {9582, 0, 0}, > + {19163, 1, 0}, > + {38326, 0, 1}, > +}; > + > +/* KMX61 devices */ > +#define KMX61_ACC 0x01 > +#define KMX61_MAG 0x02 > + > +static const struct { > + int val; > + int val2; > + int odr_bits; > +} samp_freq_table[] = { {12, 500000, 0x00}, > + {25, 0, 0x01}, > + {50, 0, 0x02}, > + {100, 0, 0x03}, > + {200, 0, 0x04}, > + {400, 0, 0x05}, > + {800, 0, 0x06}, > + {1600, 0, 0x07}, > + {0, 781000, 0x08}, > + {1, 563000, 0x09}, > + {3, 125000, 0x0A}, > + {6, 250000, 0x0B} }; > + > +static IIO_CONST_ATTR(accel_scale_available, "0.009582 0.019163 0.038326"); > +static IIO_CONST_ATTR(magn_scale_available, "0.001465"); > +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL( > + "0.781000 1.563000 3.125000 6.250000 12.500000 25 50 100 200 400 800"); > + > +static struct attribute *kmx61_attributes[] = { > + &iio_const_attr_accel_scale_available.dev_attr.attr, > + &iio_const_attr_magn_scale_available.dev_attr.attr, > + &iio_const_attr_sampling_frequency_available.dev_attr.attr, Interesting. So sampling frequency is controllable seperately for the two sensing types, but uses a single set of values. This is a rare coherent looking bit of dual sensor type hardware ;) > + NULL, > +}; > + > +static const struct attribute_group kmx61_attribute_group = { > + .attrs = kmx61_attributes, > +}; > + > +#define KMX61_ACC_CHAN(_axis, _index) { \ > + .type = IIO_ACCEL, \ > + .modified = 1, \ > + .channel2 = IIO_MOD_ ## _axis, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ > + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ > + .scan_index = _index, \ > + .scan_type = { \ > + .sign = 's', \ > + .realbits = 12, \ > + .storagebits = 16, \ > + .shift = 4, \ > + .endianness = IIO_BE, \ > + }, \ > +} > + > +#define KMX61_MAG_CHAN(_axis, _index) { \ > + .type = IIO_MAGN, \ > + .modified = 1, \ > + .channel2 = IIO_MOD_ ## _axis, \ > + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ > + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ > + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ > + .scan_index = _index, \ > + .scan_type = { \ > + .sign = 's', \ > + .realbits = 14, \ > + .storagebits = 16, \ > + .shift = 2, \ > + .endianness = IIO_BE, \ > + }, \ Wouldn't normally expect scan_index and scan_type in a driver without buffered support, but you do make use of some of the elements elsewhere and state that buffered support is on the todo list so lets leave it here. > +} > + > +static const struct iio_chan_spec kmx61_channels[] = { > + KMX61_ACC_CHAN(X, KMX61_SCAN_ACC_X), > + KMX61_ACC_CHAN(Y, KMX61_SCAN_ACC_Y), > + KMX61_ACC_CHAN(Z, KMX61_SCAN_ACC_Z), > + KMX61_MAG_CHAN(X, KMX61_SCAN_MAG_X), > + KMX61_MAG_CHAN(Y, KMX61_SCAN_MAG_Y), > + KMX61_MAG_CHAN(Z, KMX61_SCAN_MAG_Z), > +}; > + > +static int kmx61_convert_freq_to_bit(int val, int val2) > +{ > + int i; > + > + for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++) > + if (val == samp_freq_table[i].val && > + val2 == samp_freq_table[i].val2) > + return samp_freq_table[i].odr_bits; > + return -EINVAL; > +} > + > +static int kmx61_set_mode(struct kmx61_data *data, u8 mode, u8 device) > +{ > + int ret; > + > + ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY); > + if (ret < 0) { > + dev_err(&data->client->dev, "Error reading reg_stby\n"); > + return ret; > + } > + if (device & KMX61_ACC) { > + if (mode & KMX61_ACC_STBY_BIT) > + ret |= KMX61_ACC_STBY_BIT; > + else > + ret &= ~KMX61_ACC_STBY_BIT; > + } > + > + if (device & KMX61_MAG) { > + if (mode & KMX61_MAG_STBY_BIT) > + ret |= KMX61_MAG_STBY_BIT; > + else > + ret &= ~KMX61_MAG_STBY_BIT; > + } > + > + ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_STBY, ret); > + if (ret < 0) { > + dev_err(&data->client->dev, "Error writing reg_stby\n"); > + return ret; > + } > + > + return ret; > +} > + > +static int kmx61_get_mode(struct kmx61_data *data, u8 *mode, u8 device) > +{ > + int ret; > + > + ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_STBY); > + if (ret < 0) { > + dev_err(&data->client->dev, "Error reading reg_stby\n"); > + return ret; > + } > + *mode = 0; > + > + if (device & KMX61_ACC) { > + if (ret & KMX61_ACC_STBY_BIT) > + *mode |= KMX61_ACC_STBY_BIT; > + else > + *mode &= ~KMX61_ACC_STBY_BIT; > + } > + > + if (device & KMX61_MAG) { > + if (ret & KMX61_MAG_STBY_BIT) > + *mode |= KMX61_MAG_STBY_BIT; > + else > + *mode &= ~KMX61_MAG_STBY_BIT; > + } > + > + return 0; > +} > + > +static int kmx61_set_odr(struct kmx61_data *data, int val, int val2, u8 device) > +{ > + int ret; > + u8 mode; > + int lodr_bits, odr_bits; > + > + ret = kmx61_get_mode(data, &mode, KMX61_ACC | KMX61_MAG); > + if (ret < 0) > + return ret; > + > + lodr_bits = kmx61_convert_freq_to_bit(val, val2); > + if (lodr_bits < 0) > + return lodr_bits; > + > + /* To change ODR, accel and magn must be in STDBY */ > + ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG); > + if (ret < 0) > + return ret; > + > + odr_bits = 0; > + if (device & KMX61_ACC) > + odr_bits |= lodr_bits; > + if (device & KMX61_MAG) > + odr_bits |= (lodr_bits << KMX61_MAG_ODR_SHIFT); > + > + ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_ODCNTL, > + odr_bits); > + if (ret < 0) > + return ret; > + > + ret = kmx61_set_mode(data, mode, KMX61_ACC | KMX61_MAG); > + if (ret < 0) > + return ret; > + > + data->odr_bits = lodr_bits; > + > + return 0; > +} > + > +static > +int kmx61_get_odr(struct kmx61_data *data, int *val, int *val2, u8 device) > +{ int i; > + u8 lodr_bits; > + > + if (device & KMX61_ACC) > + lodr_bits = (data->odr_bits >> KMX61_ACC_ODR_SHIFT) & > + KMX61_ACC_ODR_MASK; > + else if (device & KMX61_MAG) > + lodr_bits = (data->odr_bits >> KMX61_MAG_ODR_SHIFT) & > + KMX61_MAG_ODR_MASK; > + else > + return -EINVAL; > + > + for (i = 0; i < ARRAY_SIZE(samp_freq_table); i++) > + if (lodr_bits == samp_freq_table[i].odr_bits) { > + *val = samp_freq_table[i].val; > + *val2 = samp_freq_table[i].val2; > + return 0; > + } > + return -EINVAL; > +} > + > +static int kmx61_set_range(struct kmx61_data *data, int range) > +{ > + int ret; > + > + ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_CTRL1); > + if (ret < 0) { > + dev_err(&data->client->dev, "Error reading reg_ctrl1\n"); > + return ret; > + } > + > + ret &= ~(KMX61_REG_CTRL1_GSEL0_MASK | KMX61_REG_CTRL1_GSEL1_MASK); > + ret |= kmx61_scale_table[range].gsel0 << KMX61_REG_CTRL1_GSEL0_SHIFT; > + ret |= kmx61_scale_table[range].gsel1 << KMX61_REG_CTRL1_GSEL1_SHIFT; > + > + ret = i2c_smbus_write_byte_data(data->client, KMX61_REG_CTRL1, ret); > + if (ret < 0) { > + dev_err(&data->client->dev, "Error writing reg_ctrl1\n"); > + return ret; > + } > + > + data->range = range; > + > + return 0; > +} > + I'd be tempted to use a parameter name other than val as that tends to have a fairly specific meaning in iio drivers (afterall you pass val2 in here!) scale would work or maybe microscale or similar? > +static int kmx61_set_scale(struct kmx61_data *data, int val) > +{ > + int ret, i; > + u8 mode; > + > + for (i = 0; i < ARRAY_SIZE(kmx61_scale_table); i++) { > + if (kmx61_scale_table[i].scale == val) { > + ret = kmx61_get_mode(data, &mode, > + KMX61_ACC | KMX61_MAG); > + if (ret < 0) > + return ret; > + > + ret = kmx61_set_mode(data, KMX61_ALL_STBY, > + KMX61_ACC | KMX61_MAG); > + if (ret < 0) > + return ret; > + > + ret = kmx61_set_range(data, i); > + if (ret < 0) > + return ret; > + > + ret = kmx61_set_mode(data, mode, > + KMX61_ACC | KMX61_MAG); > + if (ret < 0) > + return ret; > + > + return 0; > + } > + } > + return -EINVAL; > +} > + > +static int kmx61_chip_init(struct kmx61_data *data) > +{ > + int ret; > + > + ret = i2c_smbus_read_byte_data(data->client, KMX61_REG_WHO_AM_I); > + if (ret < 0) { > + dev_err(&data->client->dev, "Error reading who_am_i\n"); > + return ret; > + } > + > + if (ret != KMX61_CHIP_ID) { > + dev_err(&data->client->dev, > + "Wrong chip id, got %x expected %x\n", > + ret, KMX61_CHIP_ID); > + return -EINVAL; > + } > + > + /* set accel 12bit, 4g range */ > + ret = kmx61_set_range(data, KMX61_RANGE_4G); > + if (ret < 0) > + return ret; > + > + /* put accel and magnetometer in operating mode */ > + ret = kmx61_set_mode(data, 0, KMX61_ACC | KMX61_MAG); > + if (ret < 0) > + return ret; > + > + return 0; > +} > + > +static int kmx61_read_measurement(struct kmx61_data *data, int base, int offset) > +{ > + int ret; > + u8 reg = base + offset * 2; > + > + ret = i2c_smbus_read_word_data(data->client, reg); > + if (ret < 0) { > + dev_err(&data->client->dev, "failed to read reg at %x\n", reg); > + return ret; > + } > + > + return ret; > +} > + > +static int kmx61_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, int *val, > + int *val2, long mask) > +{ > + struct kmx61_data *data = iio_priv(indio_dev); > + int ret; > + u8 base_reg; > + u8 device; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + switch (chan->type) { > + case IIO_ACCEL: case IIO_MAGN: > + base_reg = KMX61_ACC_XOUT_L; > + break; > + default: > + return -EINVAL; > + } > + ret = kmx61_read_measurement(data, base_reg, chan->scan_index); > + if (ret < 0) > + return ret; > + *val = sign_extend32(ret >> chan->scan_type.shift, > + chan->scan_type.realbits - 1); > + return IIO_VAL_INT; > + case IIO_CHAN_INFO_SCALE: > + switch (chan->type) { > + case IIO_ACCEL: > + *val = 0; > + *val2 = kmx61_scale_table[data->range].scale; > + return IIO_VAL_INT_PLUS_MICRO; > + case IIO_MAGN: > + /* 14 bits res, 1465 microGauss per magn count */ > + *val = 0; > + *val2 = 1465; > + return IIO_VAL_INT_PLUS_MICRO; > + default: > + break; > + } > + case IIO_CHAN_INFO_SAMP_FREQ: > + switch (chan->type) { > + case IIO_ACCEL: > + device = KMX61_ACC; > + break; > + case IIO_MAGN: > + device = KMX61_MAG; > + break; > + default: > + return -EINVAL; > + } > + > + mutex_lock(&data->lock); > + ret = kmx61_get_odr(data, val, val2, device); > + mutex_unlock(&data->lock); > + if (ret) > + return -EINVAL; > + return IIO_VAL_INT_PLUS_MICRO; > + } > + return -EINVAL; > +} > + > +static int kmx61_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, int val, > + int val2, long mask) > +{ > + struct kmx61_data *data = iio_priv(indio_dev); > + int ret; > + u8 device; > + > + switch (mask) { > + case IIO_CHAN_INFO_SAMP_FREQ: > + switch (chan->type) { > + case IIO_ACCEL: > + device = KMX61_ACC; > + break; > + case IIO_MAGN: > + device = KMX61_MAG; > + break; > + default: > + return -EINVAL; > + } > + mutex_lock(&data->lock); > + ret = kmx61_set_odr(data, val, val2, device); > + mutex_unlock(&data->lock); > + break; > + case IIO_CHAN_INFO_SCALE: > + switch (chan->type) { > + case IIO_ACCEL: Should verify that val == 0 incase of crazy userspace input. > + mutex_lock(&data->lock); > + ret = kmx61_set_scale(data, val2); > + mutex_unlock(&data->lock); > + break; > + default: > + ret = -EINVAL; > + } > + break; > + default: > + ret = -EINVAL; > + } > + > + return ret; > +} > + > +static const struct iio_info kmx61_info = { > + .driver_module = THIS_MODULE, > + .read_raw = kmx61_read_raw, > + .write_raw = kmx61_write_raw, > + .attrs = &kmx61_attribute_group, > +}; > + > +static int kmx61_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct kmx61_data *data; > + struct iio_dev *indio_dev; > + int ret; > + > + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); > + if (!indio_dev) > + return -ENOMEM; > + > + data = iio_priv(indio_dev); > + i2c_set_clientdata(client, indio_dev); > + data->client = client; > + > + indio_dev->dev.parent = &client->dev; > + indio_dev->info = &kmx61_info; > + indio_dev->channels = kmx61_channels; > + indio_dev->num_channels = ARRAY_SIZE(kmx61_channels); > + indio_dev->modes = INDIO_DIRECT_MODE; > + > + mutex_init(&data->lock); > + > + ret = kmx61_chip_init(data); > + if (ret < 0) > + return ret; > + > + return iio_device_register(indio_dev); > +} > + > +static int kmx61_remove(struct i2c_client *client) > +{ > + struct iio_dev *indio_dev = i2c_get_clientdata(client); > + struct kmx61_data *data = iio_priv(indio_dev); > + int ret; > + > + iio_device_unregister(indio_dev); > + > + mutex_lock(&data->lock); > + ret = kmx61_set_mode(data, KMX61_ALL_STBY, KMX61_ACC | KMX61_MAG); > + mutex_unlock(&data->lock); > + > + return ret; > +} > + > +static const struct i2c_device_id kmx61_id[] = { > + {"kmx61", 0}, > + {} > +}; > + > +MODULE_DEVICE_TABLE(i2c, kmx61_id); > + > +static struct i2c_driver kmx61_driver = { > + .driver = { > + .name = "kmx61", > + }, > + .probe = kmx61_probe, > + .remove = kmx61_remove, > + .id_table = kmx61_id, > +}; > + > +module_i2c_driver(kmx61_driver); > + > +MODULE_AUTHOR("Daniel Baluta "); > +MODULE_DESCRIPTION("KMX61 accelerometer/magnetometer driver"); > +MODULE_LICENSE("GPL v2"); > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/