/* *  tslib/plugins/pthres.c * *  Copyright (C) 2003 Texas Instruments, Inc. * *  Based on: *    tslib/plugins/linear.c *    Copyright (C) 2001 Russell King. * * This file is placed under the LGPL.  Please see the file * COPYING for more details. * * Ensure a release is always pressure 0, and that a press is always >=1. */#include <stdlib.h>#include <string.h>#include <sys/types.h>#include <stdio.h>#include <unistd.h>#include <errno.h>#include <limits.h>#include "tslib.h"#include "tslib-filter.h"struct tslib_pthres {	struct tslib_module_info module;	unsigned int	pmin;	unsigned int	pmax;};static intpthres_read(struct tslib_module_info *info, struct ts_sample *samp, int nr){	struct tslib_pthres *p = (struct tslib_pthres *)info;	int ret;	static int xsave = 0, ysave = 0;	static int press = 0;	ret = info->next->ops->read(info->next, samp, nr);	if (ret >= 0) {		int nr = 0, i;		struct ts_sample *s;		for (s = samp, i = 0; i < ret; i++, s++) {			if (s->pressure < p->pmin) {				if (press != 0) {					/* release */					press = 0;					s->pressure = 0;					s->x = xsave;					s->y = ysave;				} else {					/* release with no press, outside bounds, dropping */					int left = ret - nr - 1;					if (left > 0) {						memmove(s, s + 1, left * sizeof(struct ts_sample));						s--;						continue;					}					break;				}			} else {				if (s->pressure > p->pmax) {					/* pressure outside bounds, dropping */					int left = ret - nr - 1;					if (left > 0) {						memmove(s, s + 1, left * sizeof(struct ts_sample));						s--;						continue;					}					break;				}				/* press */				press = 1;				xsave = s->x;				ysave = s->y;			}			nr++;		}		return nr;	}	return ret;}static int pthres_fini(struct tslib_module_info *info){	free(info);	return 0;}static const struct tslib_ops pthres_ops ={	.read	= pthres_read,	.fini	= pthres_fini,};static int threshold_vars(struct tslib_module_info *inf, char *str, void *data){	struct tslib_pthres *p = (struct tslib_pthres *)inf;	unsigned long v;	int err = errno;	v = strtoul(str, NULL, 0);	if (v == ULONG_MAX && errno == ERANGE)		return -1;	errno = err;	switch ((int)data) {	case 0:		p->pmin = v;		break;	case 1:		p->pmax = v;		break;	default:		return -1;	}	return 0;}static const struct tslib_vars pthres_vars[] ={	{ "pmin",	(void *)0, threshold_vars },	{ "pmax",	(void *)1, threshold_vars }};#define NR_VARS (sizeof(pthres_vars) / sizeof(pthres_vars[0]))TSAPI struct tslib_module_info *mod_init(struct tsdev *dev, const char *params){	struct tslib_pthres *p;	p = malloc(sizeof(struct tslib_pthres));	if (p == NULL)		return NULL;	p->module.ops = &pthres_ops;	p->pmin = 1;	p->pmax = INT_MAX;	/*	 * Parse the parameters.	 */	if (tslib_parse_vars(&p->module, pthres_vars, NR_VARS, params)) {		free(p);		return NULL;	}	return &p->module;}