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Diffstat (limited to 'include/linux/iio/common/cros_ec_sensors_core.h')
| -rw-r--r-- | include/linux/iio/common/cros_ec_sensors_core.h | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/include/linux/iio/common/cros_ec_sensors_core.h b/include/linux/iio/common/cros_ec_sensors_core.h new file mode 100644 index 000000000000..ce16445411ac --- /dev/null +++ b/include/linux/iio/common/cros_ec_sensors_core.h @@ -0,0 +1,180 @@ +/* + * ChromeOS EC sensor hub + * + * Copyright (C) 2016 Google, Inc + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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. + */ + +#ifndef __CROS_EC_SENSORS_CORE_H +#define __CROS_EC_SENSORS_CORE_H + +#include <linux/iio/iio.h> +#include <linux/irqreturn.h> +#include <linux/mfd/cros_ec.h> + +enum { + CROS_EC_SENSOR_X, + CROS_EC_SENSOR_Y, + CROS_EC_SENSOR_Z, + CROS_EC_SENSOR_MAX_AXIS, +}; + +/* EC returns sensor values using signed 16 bit registers */ +#define CROS_EC_SENSOR_BITS 16 + +/* + * 4 16 bit channels are allowed. + * Good enough for current sensors, they use up to 3 16 bit vectors. + */ +#define CROS_EC_SAMPLE_SIZE (sizeof(s64) * 2) + +/* Minimum sampling period to use when device is suspending */ +#define CROS_EC_MIN_SUSPEND_SAMPLING_FREQUENCY 1000 /* 1 second */ + +/** + * struct cros_ec_sensors_core_state - state data for EC sensors IIO driver + * @ec: cros EC device structure + * @cmd_lock: lock used to prevent simultaneous access to the + * commands. + * @msg: cros EC command structure + * @param: motion sensor parameters structure + * @resp: motion sensor response structure + * @type: type of motion sensor + * @loc: location where the motion sensor is placed + * @calib: calibration parameters. Note that trigger + * captured data will always provide the calibrated + * data + * @samples: static array to hold data from a single capture. + * For each channel we need 2 bytes, except for + * the timestamp. The timestamp is always last and + * is always 8-byte aligned. + * @read_ec_sensors_data: function used for accessing sensors values + * @cuur_sampl_freq: current sampling period + */ +struct cros_ec_sensors_core_state { + struct cros_ec_device *ec; + struct mutex cmd_lock; + + struct cros_ec_command *msg; + struct ec_params_motion_sense param; + struct ec_response_motion_sense *resp; + + enum motionsensor_type type; + enum motionsensor_location loc; + + s16 calib[CROS_EC_SENSOR_MAX_AXIS]; + + u8 samples[CROS_EC_SAMPLE_SIZE]; + + int (*read_ec_sensors_data)(struct iio_dev *indio_dev, + unsigned long scan_mask, s16 *data); + + int curr_sampl_freq; +}; + +/** + * cros_ec_sensors_read_lpc() - retrieve data from EC shared memory + * @indio_dev: pointer to IIO device + * @scan_mask: bitmap of the sensor indices to scan + * @data: location to store data + * + * This is the safe function for reading the EC data. It guarantees that the + * data sampled was not modified by the EC while being read. + * + * Return: 0 on success, -errno on failure. + */ +int cros_ec_sensors_read_lpc(struct iio_dev *indio_dev, unsigned long scan_mask, + s16 *data); + +/** + * cros_ec_sensors_read_cmd() - retrieve data using the EC command protocol + * @indio_dev: pointer to IIO device + * @scan_mask: bitmap of the sensor indices to scan + * @data: location to store data + * + * Return: 0 on success, -errno on failure. + */ +int cros_ec_sensors_read_cmd(struct iio_dev *indio_dev, unsigned long scan_mask, + s16 *data); + +struct platform_device; +/** + * cros_ec_sensors_core_init() - basic initialization of the core structure + * @pdev: platform device created for the sensors + * @indio_dev: iio device structure of the device + * @physical_device: true if the device refers to a physical device + * + * Return: 0 on success, -errno on failure. + */ +int cros_ec_sensors_core_init(struct platform_device *pdev, + struct iio_dev *indio_dev, bool physical_device); + +/** + * cros_ec_sensors_capture() - the trigger handler function + * @irq: the interrupt number. + * @p: a pointer to the poll function. + * + * On a trigger event occurring, if the pollfunc is attached then this + * handler is called as a threaded interrupt (and hence may sleep). It + * is responsible for grabbing data from the device and pushing it into + * the associated buffer. + * + * Return: IRQ_HANDLED + */ +irqreturn_t cros_ec_sensors_capture(int irq, void *p); + +/** + * cros_ec_motion_send_host_cmd() - send motion sense host command + * @st: pointer to state information for device + * @opt_length: optional length to reduce the response size, useful on the data + * path. Otherwise, the maximal allowed response size is used + * + * When called, the sub-command is assumed to be set in param->cmd. + * + * Return: 0 on success, -errno on failure. + */ +int cros_ec_motion_send_host_cmd(struct cros_ec_sensors_core_state *st, + u16 opt_length); + +/** + * cros_ec_sensors_core_read() - function to request a value from the sensor + * @st: pointer to state information for device + * @chan: channel specification structure table + * @val: will contain one element making up the returned value + * @val2: will contain another element making up the returned value + * @mask: specifies which values to be requested + * + * Return: the type of value returned by the device + */ +int cros_ec_sensors_core_read(struct cros_ec_sensors_core_state *st, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask); + +/** + * cros_ec_sensors_core_write() - function to write a value to the sensor + * @st: pointer to state information for device + * @chan: channel specification structure table + * @val: first part of value to write + * @val2: second part of value to write + * @mask: specifies which values to write + * + * Return: the type of value returned by the device + */ +int cros_ec_sensors_core_write(struct cros_ec_sensors_core_state *st, + struct iio_chan_spec const *chan, + int val, int val2, long mask); + +extern const struct dev_pm_ops cros_ec_sensors_pm_ops; + +/* List of extended channel specification for all sensors */ +extern const struct iio_chan_spec_ext_info cros_ec_sensors_ext_info[]; + +#endif /* __CROS_EC_SENSORS_CORE_H */ |