diff options
Diffstat (limited to 'drivers/staging/iio')
| -rw-r--r-- | drivers/staging/iio/magnetometer/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/staging/iio/magnetometer/Makefile | 1 | ||||
| -rw-r--r-- | drivers/staging/iio/magnetometer/ak8975.c | 485 |
3 files changed, 0 insertions, 497 deletions
diff --git a/drivers/staging/iio/magnetometer/Kconfig b/drivers/staging/iio/magnetometer/Kconfig index df5e0d4..a3ea69e 100644 --- a/drivers/staging/iio/magnetometer/Kconfig +++ b/drivers/staging/iio/magnetometer/Kconfig @@ -3,17 +3,6 @@ # menu "Magnetometer sensors" -config SENSORS_AK8975 - tristate "Asahi Kasei AK8975 3-Axis Magnetometer" - depends on I2C - depends on GPIOLIB - help - Say yes here to build support for Asahi Kasei AK8975 3-Axis - Magnetometer. - - To compile this driver as a module, choose M here: the module - will be called ak8975. - config SENSORS_HMC5843 tristate "Honeywell HMC5843/5883/5883L 3-Axis Magnetometer" depends on I2C diff --git a/drivers/staging/iio/magnetometer/Makefile b/drivers/staging/iio/magnetometer/Makefile index f2a753f..f9bfb2e 100644 --- a/drivers/staging/iio/magnetometer/Makefile +++ b/drivers/staging/iio/magnetometer/Makefile @@ -2,5 +2,4 @@ # Makefile for industrial I/O Magnetometer sensors # -obj-$(CONFIG_SENSORS_AK8975) += ak8975.o obj-$(CONFIG_SENSORS_HMC5843) += hmc5843.o diff --git a/drivers/staging/iio/magnetometer/ak8975.c b/drivers/staging/iio/magnetometer/ak8975.c deleted file mode 100644 index af6c320..0000000 --- a/drivers/staging/iio/magnetometer/ak8975.c +++ /dev/null @@ -1,485 +0,0 @@ -/* - * A sensor driver for the magnetometer AK8975. - * - * Magnetic compass sensor driver for monitoring magnetic flux information. - * - * Copyright (c) 2010, NVIDIA Corporation. - * - * 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. - * - * This program is distributed in the hope that it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for - * more details. - * - * You should have received a copy of the GNU General Public License along - * with this program; if not, write to the Free Software Foundation, Inc., - * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. - */ - -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/slab.h> -#include <linux/i2c.h> -#include <linux/err.h> -#include <linux/mutex.h> -#include <linux/delay.h> - -#include <linux/gpio.h> - -#include <linux/iio/iio.h> -#include <linux/iio/sysfs.h> -/* - * Register definitions, as well as various shifts and masks to get at the - * individual fields of the registers. - */ -#define AK8975_REG_WIA 0x00 -#define AK8975_DEVICE_ID 0x48 - -#define AK8975_REG_INFO 0x01 - -#define AK8975_REG_ST1 0x02 -#define AK8975_REG_ST1_DRDY_SHIFT 0 -#define AK8975_REG_ST1_DRDY_MASK (1 << AK8975_REG_ST1_DRDY_SHIFT) - -#define AK8975_REG_HXL 0x03 -#define AK8975_REG_HXH 0x04 -#define AK8975_REG_HYL 0x05 -#define AK8975_REG_HYH 0x06 -#define AK8975_REG_HZL 0x07 -#define AK8975_REG_HZH 0x08 -#define AK8975_REG_ST2 0x09 -#define AK8975_REG_ST2_DERR_SHIFT 2 -#define AK8975_REG_ST2_DERR_MASK (1 << AK8975_REG_ST2_DERR_SHIFT) - -#define AK8975_REG_ST2_HOFL_SHIFT 3 -#define AK8975_REG_ST2_HOFL_MASK (1 << AK8975_REG_ST2_HOFL_SHIFT) - -#define AK8975_REG_CNTL 0x0A -#define AK8975_REG_CNTL_MODE_SHIFT 0 -#define AK8975_REG_CNTL_MODE_MASK (0xF << AK8975_REG_CNTL_MODE_SHIFT) -#define AK8975_REG_CNTL_MODE_POWER_DOWN 0 -#define AK8975_REG_CNTL_MODE_ONCE 1 -#define AK8975_REG_CNTL_MODE_SELF_TEST 8 -#define AK8975_REG_CNTL_MODE_FUSE_ROM 0xF - -#define AK8975_REG_RSVC 0x0B -#define AK8975_REG_ASTC 0x0C -#define AK8975_REG_TS1 0x0D -#define AK8975_REG_TS2 0x0E -#define AK8975_REG_I2CDIS 0x0F -#define AK8975_REG_ASAX 0x10 -#define AK8975_REG_ASAY 0x11 -#define AK8975_REG_ASAZ 0x12 - -#define AK8975_MAX_REGS AK8975_REG_ASAZ - -/* - * Miscellaneous values. - */ -#define AK8975_MAX_CONVERSION_TIMEOUT 500 -#define AK8975_CONVERSION_DONE_POLL_TIME 10 - -/* - * Per-instance context data for the device. - */ -struct ak8975_data { - struct i2c_client *client; - struct attribute_group attrs; - struct mutex lock; - u8 asa[3]; - long raw_to_gauss[3]; - u8 reg_cache[AK8975_MAX_REGS]; - int eoc_gpio; -}; - -static const int ak8975_index_to_reg[] = { - AK8975_REG_HXL, AK8975_REG_HYL, AK8975_REG_HZL, -}; - -/* - * Helper function to write to the I2C device's registers. - */ -static int ak8975_write_data(struct i2c_client *client, - u8 reg, u8 val, u8 mask, u8 shift) -{ - struct iio_dev *indio_dev = i2c_get_clientdata(client); - struct ak8975_data *data = iio_priv(indio_dev); - u8 regval; - int ret; - - regval = (data->reg_cache[reg] & ~mask) | (val << shift); - ret = i2c_smbus_write_byte_data(client, reg, regval); - if (ret < 0) { - dev_err(&client->dev, "Write to device fails status %x\n", ret); - return ret; - } - data->reg_cache[reg] = regval; - - return 0; -} - -/* - * Perform some start-of-day setup, including reading the asa calibration - * values and caching them. - */ -static int ak8975_setup(struct i2c_client *client) -{ - struct iio_dev *indio_dev = i2c_get_clientdata(client); - struct ak8975_data *data = iio_priv(indio_dev); - u8 device_id; - int ret; - - /* Confirm that the device we're talking to is really an AK8975. */ - ret = i2c_smbus_read_byte_data(client, AK8975_REG_WIA); - if (ret < 0) { - dev_err(&client->dev, "Error reading WIA\n"); - return ret; - } - device_id = ret; - if (device_id != AK8975_DEVICE_ID) { - dev_err(&client->dev, "Device ak8975 not found\n"); - return -ENODEV; - } - - /* Write the fused rom access mode. */ - ret = ak8975_write_data(client, - AK8975_REG_CNTL, - AK8975_REG_CNTL_MODE_FUSE_ROM, - AK8975_REG_CNTL_MODE_MASK, - AK8975_REG_CNTL_MODE_SHIFT); - if (ret < 0) { - dev_err(&client->dev, "Error in setting fuse access mode\n"); - return ret; - } - - /* Get asa data and store in the device data. */ - ret = i2c_smbus_read_i2c_block_data(client, AK8975_REG_ASAX, - 3, data->asa); - if (ret < 0) { - dev_err(&client->dev, "Not able to read asa data\n"); - return ret; - } - - /* After reading fuse ROM data set power-down mode */ - ret = ak8975_write_data(client, - AK8975_REG_CNTL, - AK8975_REG_CNTL_MODE_POWER_DOWN, - AK8975_REG_CNTL_MODE_MASK, - AK8975_REG_CNTL_MODE_SHIFT); - if (ret < 0) { - dev_err(&client->dev, "Error in setting power-down mode\n"); - return ret; - } - -/* - * Precalculate scale factor (in Gauss units) for each axis and - * store in the device data. - * - * This scale factor is axis-dependent, and is derived from 3 calibration - * factors ASA(x), ASA(y), and ASA(z). - * - * These ASA values are read from the sensor device at start of day, and - * cached in the device context struct. - * - * Adjusting the flux value with the sensitivity adjustment value should be - * done via the following formula: - * - * Hadj = H * ( ( ( (ASA-128)*0.5 ) / 128 ) + 1 ) - * - * where H is the raw value, ASA is the sensitivity adjustment, and Hadj - * is the resultant adjusted value. - * - * We reduce the formula to: - * - * Hadj = H * (ASA + 128) / 256 - * - * H is in the range of -4096 to 4095. The magnetometer has a range of - * +-1229uT. To go from the raw value to uT is: - * - * HuT = H * 1229/4096, or roughly, 3/10. - * - * Since 1uT = 100 gauss, our final scale factor becomes: - * - * Hadj = H * ((ASA + 128) / 256) * 3/10 * 100 - * Hadj = H * ((ASA + 128) * 30 / 256 - * - * Since ASA doesn't change, we cache the resultant scale factor into the - * device context in ak8975_setup(). - */ - data->raw_to_gauss[0] = ((data->asa[0] + 128) * 30) >> 8; - data->raw_to_gauss[1] = ((data->asa[1] + 128) * 30) >> 8; - data->raw_to_gauss[2] = ((data->asa[2] + 128) * 30) >> 8; - - return 0; -} - -static int wait_conversion_complete_gpio(struct ak8975_data *data) -{ - struct i2c_client *client = data->client; - u32 timeout_ms = AK8975_MAX_CONVERSION_TIMEOUT; - int ret; - - /* Wait for the conversion to complete. */ - while (timeout_ms) { - msleep(AK8975_CONVERSION_DONE_POLL_TIME); - if (gpio_get_value(data->eoc_gpio)) - break; - timeout_ms -= AK8975_CONVERSION_DONE_POLL_TIME; - } - if (!timeout_ms) { - dev_err(&client->dev, "Conversion timeout happened\n"); - return -EINVAL; - } - - ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST1); - if (ret < 0) - dev_err(&client->dev, "Error in reading ST1\n"); - - return ret; -} - -static int wait_conversion_complete_polled(struct ak8975_data *data) -{ - struct i2c_client *client = data->client; - u8 read_status; - u32 timeout_ms = AK8975_MAX_CONVERSION_TIMEOUT; - int ret; - - /* Wait for the conversion to complete. */ - while (timeout_ms) { - msleep(AK8975_CONVERSION_DONE_POLL_TIME); - ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST1); - if (ret < 0) { - dev_err(&client->dev, "Error in reading ST1\n"); - return ret; - } - read_status = ret; - if (read_status) - break; - timeout_ms -= AK8975_CONVERSION_DONE_POLL_TIME; - } - if (!timeout_ms) { - dev_err(&client->dev, "Conversion timeout happened\n"); - return -EINVAL; - } - return read_status; -} - -/* - * Emits the raw flux value for the x, y, or z axis. - */ -static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val) -{ - struct ak8975_data *data = iio_priv(indio_dev); - struct i2c_client *client = data->client; - u16 meas_reg; - s16 raw; - int ret; - - mutex_lock(&data->lock); - - /* Set up the device for taking a sample. */ - ret = ak8975_write_data(client, - AK8975_REG_CNTL, - AK8975_REG_CNTL_MODE_ONCE, - AK8975_REG_CNTL_MODE_MASK, - AK8975_REG_CNTL_MODE_SHIFT); - if (ret < 0) { - dev_err(&client->dev, "Error in setting operating mode\n"); - goto exit; - } - - /* Wait for the conversion to complete. */ - if (gpio_is_valid(data->eoc_gpio)) - ret = wait_conversion_complete_gpio(data); - else - ret = wait_conversion_complete_polled(data); - if (ret < 0) - goto exit; - - if (ret & AK8975_REG_ST1_DRDY_MASK) { - ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST2); - if (ret < 0) { - dev_err(&client->dev, "Error in reading ST2\n"); - goto exit; - } - if (ret & (AK8975_REG_ST2_DERR_MASK | - AK8975_REG_ST2_HOFL_MASK)) { - dev_err(&client->dev, "ST2 status error 0x%x\n", ret); - ret = -EINVAL; - goto exit; - } - } - - /* Read the flux value from the appropriate register - (the register is specified in the iio device attributes). */ - ret = i2c_smbus_read_word_data(client, ak8975_index_to_reg[index]); - if (ret < 0) { - dev_err(&client->dev, "Read axis data fails\n"); - goto exit; - } - meas_reg = ret; - - mutex_unlock(&data->lock); - - /* Endian conversion of the measured values. */ - raw = (s16) (le16_to_cpu(meas_reg)); - - /* Clamp to valid range. */ - raw = clamp_t(s16, raw, -4096, 4095); - *val = raw; - return IIO_VAL_INT; - -exit: - mutex_unlock(&data->lock); - return ret; -} - -static int ak8975_read_raw(struct iio_dev *indio_dev, - struct iio_chan_spec const *chan, - int *val, int *val2, - long mask) -{ - struct ak8975_data *data = iio_priv(indio_dev); - - switch (mask) { - case IIO_CHAN_INFO_RAW: - return ak8975_read_axis(indio_dev, chan->address, val); - case IIO_CHAN_INFO_SCALE: - *val = data->raw_to_gauss[chan->address]; - return IIO_VAL_INT; - } - return -EINVAL; -} - -#define AK8975_CHANNEL(axis, index) \ - { \ - .type = IIO_MAGN, \ - .modified = 1, \ - .channel2 = IIO_MOD_##axis, \ - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ - BIT(IIO_CHAN_INFO_SCALE), \ - .address = index, \ - } - -static const struct iio_chan_spec ak8975_channels[] = { - AK8975_CHANNEL(X, 0), AK8975_CHANNEL(Y, 1), AK8975_CHANNEL(Z, 2), -}; - -static const struct iio_info ak8975_info = { - .read_raw = &ak8975_read_raw, - .driver_module = THIS_MODULE, -}; - -static int ak8975_probe(struct i2c_client *client, - const struct i2c_device_id *id) -{ - struct ak8975_data *data; - struct iio_dev *indio_dev; - int eoc_gpio; - int err; - - /* Grab and set up the supplied GPIO. */ - if (client->dev.platform_data == NULL) - eoc_gpio = -1; - else - eoc_gpio = *(int *)(client->dev.platform_data); - - /* We may not have a GPIO based IRQ to scan, that is fine, we will - poll if so */ - if (gpio_is_valid(eoc_gpio)) { - err = gpio_request_one(eoc_gpio, GPIOF_IN, "ak_8975"); - if (err < 0) { - dev_err(&client->dev, - "failed to request GPIO %d, error %d\n", - eoc_gpio, err); - goto exit; - } - } - - /* Register with IIO */ - indio_dev = iio_device_alloc(sizeof(*data)); - if (indio_dev == NULL) { - err = -ENOMEM; - goto exit_gpio; - } - data = iio_priv(indio_dev); - i2c_set_clientdata(client, indio_dev); - /* Perform some basic start-of-day setup of the device. */ - err = ak8975_setup(client); - if (err < 0) { - dev_err(&client->dev, "AK8975 initialization fails\n"); - goto exit_free_iio; - } - - data->client = client; - mutex_init(&data->lock); - data->eoc_gpio = eoc_gpio; - indio_dev->dev.parent = &client->dev; - indio_dev->channels = ak8975_channels; - indio_dev->num_channels = ARRAY_SIZE(ak8975_channels); - indio_dev->info = &ak8975_info; - indio_dev->modes = INDIO_DIRECT_MODE; - - err = iio_device_register(indio_dev); - if (err < 0) - goto exit_free_iio; - - return 0; - -exit_free_iio: - iio_device_free(indio_dev); -exit_gpio: - if (gpio_is_valid(eoc_gpio)) - gpio_free(eoc_gpio); -exit: - return err; -} - -static int ak8975_remove(struct i2c_client *client) -{ - struct iio_dev *indio_dev = i2c_get_clientdata(client); - struct ak8975_data *data = iio_priv(indio_dev); - - iio_device_unregister(indio_dev); - - if (gpio_is_valid(data->eoc_gpio)) - gpio_free(data->eoc_gpio); - - iio_device_free(indio_dev); - - return 0; -} - -static const struct i2c_device_id ak8975_id[] = { - {"ak8975", 0}, - {} -}; - -MODULE_DEVICE_TABLE(i2c, ak8975_id); - -static const struct of_device_id ak8975_of_match[] = { - { .compatible = "asahi-kasei,ak8975", }, - { .compatible = "ak8975", }, - { } -}; -MODULE_DEVICE_TABLE(of, ak8975_of_match); - -static struct i2c_driver ak8975_driver = { - .driver = { - .name = "ak8975", - .of_match_table = ak8975_of_match, - }, - .probe = ak8975_probe, - .remove = ak8975_remove, - .id_table = ak8975_id, -}; -module_i2c_driver(ak8975_driver); - -MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); -MODULE_DESCRIPTION("AK8975 magnetometer driver"); -MODULE_LICENSE("GPL"); |