path: root/drivers/misc/lis3lv02d/lis3lv02d.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  lis3lv02d.c - ST LIS3LV02DL accelerometer driver
 *
 *  Copyright (C) 2007-2008 Yan Burman
 *  Copyright (C) 2008 Eric Piel
 *  Copyright (C) 2008-2009 Pavel Machek
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/sched/signal.h>
#include <linux/dmi.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/delay.h>
#include <linux/wait.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/freezer.h>
#include <linux/uaccess.h>
#include <linux/miscdevice.h>
#include <linux/pm_runtime.h>
#include <linux/atomic.h>
#include <linux/of.h>
#include "lis3lv02d.h"

#define DRIVER_NAME     "lis3lv02d"

/* joystick device poll interval in milliseconds */
#define MDPS_POLL_INTERVAL 50
#define MDPS_POLL_MIN	   0
#define MDPS_POLL_MAX	   2000

#define LIS3_SYSFS_POWERDOWN_DELAY 5000 /* In milliseconds */

#define SELFTEST_OK	       0
#define SELFTEST_FAIL	       -1
#define SELFTEST_IRQ	       -2

#define IRQ_LINE0	       0
#define IRQ_LINE1	       1

/*
 * The sensor can also generate interrupts (DRDY) but it's pretty pointless
 * because they are generated even if the data do not change. So it's better
 * to keep the interrupt for the free-fall event. The values are updated at
 * 40Hz (at the lowest frequency), but as it can be pretty time consuming on
 * some low processor, we poll the sensor only at 20Hz... enough for the
 * joystick.
 */

#define LIS3_PWRON_DELAY_WAI_12B	(5000)
#define LIS3_PWRON_DELAY_WAI_8B		(3000)

/*
 * LIS3LV02D spec says 1024 LSBs corresponds 1 G -> 1LSB is 1000/1024 mG
 * LIS302D spec says: 18 mG / digit
 * LIS3_ACCURACY is used to increase accuracy of the intermediate
 * calculation results.
 */
#define LIS3_ACCURACY			1024
/* Sensitivity values for -2G +2G scale */
#define LIS3_SENSITIVITY_12B		((LIS3_ACCURACY * 1000) / 1024)
#define LIS3_SENSITIVITY_8B		(18 * LIS3_ACCURACY)

/*
 * LIS331DLH spec says 1LSBs corresponds 4G/4096 -> 1LSB is 1000/1024 mG.
 * Below macros defines sensitivity values for +/-2G. Dataout bits for
 * +/-2G range is 12 bits so 4 bits adjustment must be done to get 12bit
 * data from 16bit value. Currently this driver supports only 2G range.
 */
#define LIS3DLH_SENSITIVITY_2G		((LIS3_ACCURACY * 1000) / 1024)
#define SHIFT_ADJ_2G			4

#define LIS3_DEFAULT_FUZZ_12B		3
#define LIS3_DEFAULT_FLAT_12B		3
#define LIS3_DEFAULT_FUZZ_8B		1
#define LIS3_DEFAULT_FLAT_8B		1

struct lis3lv02d lis3_dev = {
	.misc_wait   = __WAIT_QUEUE_HEAD_INITIALIZER(lis3_dev.misc_wait),
};
EXPORT_SYMBOL_GPL(lis3_dev);

/* just like param_set_int() but does sanity-check so that it won't point
 * over the axis array size
 */
static int param_set_axis(const char *val, const struct kernel_param *kp)
{
	int ret = param_set_int(val, kp);
	if (!ret) {
		int val = *(int *)kp->arg;
		if (val < 0)
			val = -val;
		if (!val || val > 3)
			return -EINVAL;
	}
	return ret;
}

static const struct kernel_param_ops param_ops_axis = {
	.set = param_set_axis,
	.get = param_get_int,
};

#define param_check_axis(name, p) param_check_int(name, p)

module_param_array_named(axes, lis3_dev.ac.as_array, axis, NULL, 0644);
MODULE_PARM_DESC(axes, "Axis-mapping for x,y,z directions");

static s16 lis3lv02d_read_8(struct lis3lv02d *lis3, int reg)
{
	s8 lo;
	if (lis3->read(lis3, reg, &lo) < 0)
		return 0;

	return lo;
}

static s16 lis3lv02d_read_12(struct lis3lv02d *lis3, int reg)
{
	u8 lo, hi;

	lis3->read(lis3, reg - 1, &lo);
	lis3->read(lis3, reg, &hi);
	/* In "12 bit right justified" mode, bit 6, bit 7, bit 8 = bit 5 */
	return (s16)((hi << 8) | lo);
}

/* 12bits for 2G range, 13 bits for 4G range and 14 bits for 8G range */
static s16 lis331dlh_read_data(struct lis3lv02d *lis3, int reg)
{
	u8 lo, hi;
	int v