[mirror_ubuntu-hirsute-kernel.git] / include / linux / iio / common / cros_ec_sensors_core.h

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * ChromeOS EC sensor hub
 *
 * Copyright (C) 2016 Google, Inc
 */

#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 */
Commit	Line	Data
9c92ab61	1	/* SPDX-License-Identifier: GPL-2.0-only */
974e6f02 EBS	2	/*
	3	* ChromeOS EC sensor hub
	4	*
	5	* Copyright (C) 2016 Google, Inc
974e6f02 EBS	6	*/
	7
	8	#ifndef __CROS_EC_SENSORS_CORE_H
	9	#define __CROS_EC_SENSORS_CORE_H
	10
5a0b8cb4	11	#include <linux/iio/iio.h>
974e6f02	12	#include <linux/irqreturn.h>
5a0b8cb4	13	#include <linux/mfd/cros_ec.h>
974e6f02 EBS	14
	15	enum {
	16	CROS_EC_SENSOR_X,
	17	CROS_EC_SENSOR_Y,
	18	CROS_EC_SENSOR_Z,
	19	CROS_EC_SENSOR_MAX_AXIS,
	20	};
	21
	22	/* EC returns sensor values using signed 16 bit registers */
	23	#define CROS_EC_SENSOR_BITS 16
	24
	25	/*
	26	* 4 16 bit channels are allowed.
	27	* Good enough for current sensors, they use up to 3 16 bit vectors.
	28	*/
	29	#define CROS_EC_SAMPLE_SIZE (sizeof(s64) * 2)
	30
	31	/* Minimum sampling period to use when device is suspending */
	32	#define CROS_EC_MIN_SUSPEND_SAMPLING_FREQUENCY 1000 /* 1 second */
	33
	34	/**
	35	* struct cros_ec_sensors_core_state - state data for EC sensors IIO driver
	36	* @ec: cros EC device structure
	37	* @cmd_lock: lock used to prevent simultaneous access to the
	38	* commands.
	39	* @msg: cros EC command structure
	40	* @param: motion sensor parameters structure
	41	* @resp: motion sensor response structure
	42	* @type: type of motion sensor
	43	* @loc: location where the motion sensor is placed
	44	* @calib: calibration parameters. Note that trigger
	45	* captured data will always provide the calibrated
	46	* data
	47	* @samples: static array to hold data from a single capture.
	48	* For each channel we need 2 bytes, except for
	49	* the timestamp. The timestamp is always last and
	50	* is always 8-byte aligned.
	51	* @read_ec_sensors_data: function used for accessing sensors values
	52	* @cuur_sampl_freq: current sampling period
	53	*/
	54	struct cros_ec_sensors_core_state {
	55	struct cros_ec_device *ec;
	56	struct mutex cmd_lock;
	57
	58	struct cros_ec_command *msg;
	59	struct ec_params_motion_sense param;
	60	struct ec_response_motion_sense *resp;
	61
	62	enum motionsensor_type type;
	63	enum motionsensor_location loc;
	64
	65	s16 calib[CROS_EC_SENSOR_MAX_AXIS];
	66
	67	u8 samples[CROS_EC_SAMPLE_SIZE];
	68
	69	int (read_ec_sensors_data)(struct iio_dev indio_dev,
	70	unsigned long scan_mask, s16 *data);
	71
	72	int curr_sampl_freq;
	73	};
	74
	75	/**
	76	* cros_ec_sensors_read_lpc() - retrieve data from EC shared memory
	77	* @indio_dev: pointer to IIO device
78	* @scan_mask: bitmap of the sensor indices to scan
79	* @data: location to store data
80	*
81	* This is the safe function for reading the EC data. It guarantees that the
82	* data sampled was not modified by the EC while being read.
83	*
84	* Return: 0 on success, -errno on failure.
85	*/
86	int cros_ec_sensors_read_lpc(struct iio_dev *indio_dev, unsigned long scan_mask,
87	s16 *data);
88
89	/**
90	* cros_ec_sensors_read_cmd() - retrieve data using the EC command protocol
91	* @indio_dev: pointer to IIO device
92	* @scan_mask: bitmap of the sensor indices to scan
93	* @data: location to store data
94	*
95	* Return: 0 on success, -errno on failure.
96	*/
97	int cros_ec_sensors_read_cmd(struct iio_dev *indio_dev, unsigned long scan_mask,
98	s16 *data);
99
5a0b8cb4	100	struct platform_device;
974e6f02 EBS	101	/**
	102	* cros_ec_sensors_core_init() - basic initialization of the core structure
	103	* @pdev: platform device created for the sensors
	104	* @indio_dev: iio device structure of the device
	105	* @physical_device: true if the device refers to a physical device
	106	*
	107	* Return: 0 on success, -errno on failure.
	108	*/
	109	int cros_ec_sensors_core_init(struct platform_device *pdev,
	110	struct iio_dev *indio_dev, bool physical_device);
	111
	112	/**
	113	* cros_ec_sensors_capture() - the trigger handler function
	114	* @irq: the interrupt number.
	115	* @p: a pointer to the poll function.
	116	*
	117	* On a trigger event occurring, if the pollfunc is attached then this
	118	* handler is called as a threaded interrupt (and hence may sleep). It
	119	* is responsible for grabbing data from the device and pushing it into
	120	* the associated buffer.
	121	*
	122	* Return: IRQ_HANDLED
	123	*/
	124	irqreturn_t cros_ec_sensors_capture(int irq, void *p);
	125
	126	/**
	127	* cros_ec_motion_send_host_cmd() - send motion sense host command
	128	* @st: pointer to state information for device
	129	* @opt_length: optional length to reduce the response size, useful on the data
	130	* path. Otherwise, the maximal allowed response size is used
	131	*
	132	* When called, the sub-command is assumed to be set in param->cmd.
	133	*
	134	* Return: 0 on success, -errno on failure.
	135	*/
	136	int cros_ec_motion_send_host_cmd(struct cros_ec_sensors_core_state *st,
	137	u16 opt_length);
	138
	139	/**
	140	* cros_ec_sensors_core_read() - function to request a value from the sensor
	141	* @st: pointer to state information for device
	142	* @chan: channel specification structure table
	143	* @val: will contain one element making up the returned value
	144	* @val2: will contain another element making up the returned value
	145	* @mask: specifies which values to be requested
	146	*
	147	* Return: the type of value returned by the device
	148	*/
	149	int cros_ec_sensors_core_read(struct cros_ec_sensors_core_state *st,
	150	struct iio_chan_spec const *chan,
	151	int val, int val2, long mask);
	152
	153	/**
	154	* cros_ec_sensors_core_write() - function to write a value to the sensor
	155	* @st: pointer to state information for device
	156	* @chan: channel specification structure table
	157	* @val: first part of value to write
	158	* @val2: second part of value to write
	159	* @mask: specifies which values to write
	160	*
	161	* Return: the type of value returned by the device
	162	*/
	163	int cros_ec_sensors_core_write(struct cros_ec_sensors_core_state *st,
	164	struct iio_chan_spec const *chan,
165	int val, int val2, long mask);
166
0dad1ece GG	167	extern const struct dev_pm_ops cros_ec_sensors_pm_ops;
0dad1ece GG	168
974e6f02 EBS	169	/* List of extended channel specification for all sensors */
	170	extern const struct iio_chan_spec_ext_info cros_ec_sensors_ext_info[];
	171
	172	#endif /* __CROS_EC_SENSORS_CORE_H */