1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License, or
* (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Copyright (C) 2008,2009 by Openmoko, Inc.
* Author: Nelson Castillo <arhuaco@freaks-unidos.net>
* All rights reserved.
*
* Linearly scale touchscreen values.
*
* Expose the TS_FILTER_LINEAR_NCONSTANTS for the linear transformation
* using sysfs.
*
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/string.h>
#include "ts_filter_linear.h"
struct ts_filter_linear;
/* Sysfs code. */
struct const_obj {
/* The actual private object. */
struct ts_filter_linear *tsfl;
/* Our kobject. */
struct kobject kobj;
};
#define to_const_obj(x) container_of(x, struct const_obj, kobj)
struct const_attribute {
struct attribute attr;
ssize_t (*show)(struct const_obj *const, struct const_attribute *attr,
char *buf);
ssize_t (*store)(struct const_obj *const, struct const_attribute *attr,
const char *buf, size_t count);
};
#define to_const_attr(x) container_of(x, struct const_attribute, attr)
/* Private linear filter structure. */
struct ts_filter_linear {
/* Private configuration for this filter. */
struct ts_filter_linear_configuration *config;
/* Generic filter API. */
struct ts_filter tsf;
/* Linear constants for the transformation. */
int constants[TS_FILTER_LINEAR_NCONSTANTS];
/* Sysfs. */
/* Our const_object. */
struct const_obj c_obj;
/* Our type. We will stick operations to it. */
struct kobj_type const_ktype;
/* Attrs. of the virtual files. */
struct const_attribute kattrs[TS_FILTER_LINEAR_NCONSTANTS];
/* Default Attrs. Always NULL for us. */
struct attribute *attrs[TS_FILTER_LINEAR_NCONSTANTS + 1];
/* Storage for the name of the virtual files. */
char attr_names[TS_FILTER_LINEAR_NCONSTANTS][2];
};
#define ts_filter_to_filter_linear(f) \
container_of(f, struct ts_filter_linear, tsf)
/* Sysfs functions. */
static ssize_t const_attr_show(struct kobject *kobj,
struct attribute *attr,
char *buf)
{
struct const_attribute *a = to_const_attr(attr);
return a->show(to_const_obj(kobj), a, buf);
}
static ssize_t const_attr_store(struct kobject *kobj,
struct attribute *attr,
const char *buf, size_t len)
{
struct const_attribute *a = to_const_attr(attr);
return a->store(to_const_obj(kobj), a, buf, len);
}
static struct sysfs_ops const_sysfs_ops = {
.show = const_attr_show,
.store = const_attr_store,
};
static void const_release(struct kobject *kobj)
{
kfree(to_const_obj(kobj)->tsfl);
}
static ssize_t const_show(struct const_obj *obj, struct const_attribute *attr,
char *buf)
{
int who;
sscanf(attr->attr.name, "%d", &who);
return sprintf(buf, "%d\n", obj->tsfl->constants[who]);
}
static ssize_t const_store(struct const_obj *obj, struct const_attribute *attr,
const char *buf, size_t count)
{
int who;
sscanf(attr->attr.name, "%d", &who);
sscanf(buf, "%d", &obj->tsfl->constants[who]);
return count;
}
/* Filter functions. */
static struct ts_filter *ts_filter_linear_create(
struct platform_device *pdev,
const struct ts_filter_configuration *conf,
int count_coords)
{
struct ts_filter_linear *tsfl;
int i;
int ret;
tsfl = kzalloc(sizeof(struct ts_filter_linear), GFP_KERNEL);
if (!tsfl)
return NULL;
tsfl->config = container_of(conf,
struct ts_filter_linear_configuration,
config);
tsfl->tsf.count_coords = count_coords;
for (i = 0; i < TS_FILTER_LINEAR_NCONSTANTS; ++i) {
tsfl->constants[i] = tsfl->config->constants[i];
/* sysfs */
sprintf(tsfl->attr_names[i], "%d", i);
tsfl->kattrs[i].attr.name = tsfl->attr_names[i];
tsfl->kattrs[i].attr.mode = 0666;
tsfl->kattrs[i].show = const_show;
tsfl->kattrs[i].store = const_store;
tsfl->attrs[i] = &tsfl->kattrs[i].attr;
}
tsfl->attrs[i] = NULL;
tsfl->const_ktype.sysfs_ops = &const_sysfs_ops;
tsfl->const_ktype.release = const_release;
tsfl->const_ktype.default_attrs = tsfl->attrs;
tsfl->c_obj.tsfl = tsfl; /* kernel frees tsfl in const_release */
ret = kobject_init_and_add(&tsfl->c_obj.kobj, &tsfl->const_ktype,
&pdev->dev.kobj, "calibration");
if (ret) {
kobject_put(&tsfl->c_obj.kobj);
return NULL;
}
dev_info(&pdev->dev, "Created Linear filter coords:%d\n", count_coords);
return &tsfl->tsf;
}
static void ts_filter_linear_destroy(struct ts_filter *tsf)
{
struct ts_filter_linear *tsfl = ts_filter_to_filter_linear(tsf);
/* Kernel frees tsfl in const_release. */
kobject_put(&tsfl->c_obj.kobj);
}
static void ts_filter_linear_scale(struct ts_filter *tsf, int *coords)
{
struct ts_filter_linear *tsfl = ts_filter_to_filter_linear(tsf);
int *k = tsfl->constants;
int c0 = coords[tsfl->config->coord0];
int c1 = coords[tsfl->config->coord1];
coords[tsfl->config->coord0] = (k[2] + k[0] * c0 + k[1] * c1) / k[6];
coords[tsfl->config->coord1] = (k[5] + k[3] * c0 + k[4] * c1) / k[6];
}
const struct ts_filter_api ts_filter_linear_api = {
.create = ts_filter_linear_create,
.destroy = ts_filter_linear_destroy,
.scale = ts_filter_linear_scale,
};
EXPORT_SYMBOL_GPL(ts_filter_linear_api);
|
