linux/drivers/iio/accel/cros_ec_accel_legacy.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Driver for older Chrome OS EC accelerometer
 *
 * Copyright 2017 Google, Inc
 *
 * This driver uses the memory mapper cros-ec interface to communicate
 * with the Chrome OS EC about accelerometer data or older commands.
 * Accelerometer access is presented through iio sysfs.
 */

#include <linux/delay.h>
#include <linux/device.h>
#include <linux/iio/buffer.h>
#include <linux/iio/common/cros_ec_sensors_core.h>
#include <linux/iio/iio.h>
#include <linux/iio/kfifo_buf.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
#include <linux/platform_device.h>

#define DRV_NAME …

#define CROS_EC_SENSOR_LEGACY_NUM …
/*
 * Sensor scale hard coded at 10 bits per g, computed as:
 * g / (2^10 - 1) = 0.009586168; with g = 9.80665 m.s^-2
 */
#define ACCEL_LEGACY_NSCALE …

/*
 * Sensor frequency is hard-coded to 10Hz.
 */
static const int cros_ec_legacy_sample_freq[] = …;

static int cros_ec_accel_legacy_read_cmd(struct iio_dev *indio_dev,
				  unsigned long scan_mask, s16 *data)
{ … }

static int cros_ec_accel_legacy_read(struct iio_dev *indio_dev,
				     struct iio_chan_spec const *chan,
				     int *val, int *val2, long mask)
{ … }

static int cros_ec_accel_legacy_write(struct iio_dev *indio_dev,
				      struct iio_chan_spec const *chan,
				      int val, int val2, long mask)
{ … }

/**
 * cros_ec_accel_legacy_read_avail() - get available values
 * @indio_dev:		pointer to state information for device
 * @chan:	channel specification structure table
 * @vals:	list of available values
 * @type:	type of data returned
 * @length:	number of data returned in the array
 * @mask:	specifies which values to be requested
 *
 * Return:	an error code or IIO_AVAIL_LIST
 */
static int cros_ec_accel_legacy_read_avail(struct iio_dev *indio_dev,
					   struct iio_chan_spec const *chan,
					   const int **vals,
					   int *type,
					   int *length,
					   long mask)
{ … }

static const struct iio_info cros_ec_accel_legacy_info = …;

/*
 * Present the channel using HTML5 standard:
 * need to invert X and Y and invert some lid axis.
 */
#define CROS_EC_ACCEL_ROTATE_AXIS(_axis) …

#define CROS_EC_ACCEL_LEGACY_CHAN(_axis) …								\

static const struct iio_chan_spec cros_ec_accel_legacy_channels[] = …;

static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
{ … }

static struct platform_driver cros_ec_accel_platform_driver = …;
module_platform_driver(…) …;

MODULE_DESCRIPTION(…) …;
MODULE_AUTHOR(…) …;
MODULE_LICENSE(…) …;
MODULE_ALIAS(…) …;