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
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
|
/*
* STK1160 driver
*
* Copyright (C) 2012 Ezequiel Garcia
* <elezegarcia--a.t--gmail.com>
*
* Based on Easycap driver by R.M. Thomas
* Copyright (C) 2010 R.M. Thomas
* <rmthomas--a.t--sciolus.org>
*
* 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; either 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.
*
*/
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/i2c.h>
#include "stk1160.h"
#include "stk1160-reg.h"
static unsigned int i2c_debug;
module_param(i2c_debug, int, 0644);
MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
#define dprintk_i2c(fmt, args...) \
do { \
if (i2c_debug) \
printk(KERN_DEBUG fmt, ##args); \
} while (0)
static int stk1160_i2c_busy_wait(struct stk1160 *dev, u8 wait_bit_mask)
{
unsigned long end;
u8 flag;
/* Wait until read/write finish bit is set */
end = jiffies + msecs_to_jiffies(STK1160_I2C_TIMEOUT);
while (time_is_after_jiffies(end)) {
stk1160_read_reg(dev, STK1160_SICTL+1, &flag);
/* read/write done? */
if (flag & wait_bit_mask)
goto done;
usleep_range(10 * USEC_PER_MSEC, 20 * USEC_PER_MSEC);
}
return -ETIMEDOUT;
done:
return 0;
}
static int stk1160_i2c_write_reg(struct stk1160 *dev, u8 addr,
u8 reg, u8 value)
{
int rc;
/* Set serial device address */
rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
if (rc < 0)
return rc;
/* Set i2c device register sub-address */
rc = stk1160_write_reg(dev, STK1160_SBUSW_WA, reg);
if (rc < 0)
return rc;
/* Set i2c device register value */
rc = stk1160_write_reg(dev, STK1160_SBUSW_WD, value);
if (rc < 0)
return rc;
/* Start write now */
rc = stk1160_write_reg(dev, STK1160_SICTL, 0x01);
if (rc < 0)
return rc;
rc = stk1160_i2c_busy_wait(dev, 0x04);
if (rc < 0)
return rc;
return 0;
}
static int stk1160_i2c_read_reg(struct stk1160 *dev, u8 addr,
u8 reg, u8 *value)
{
int rc;
/* Set serial device address */
rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
if (rc < 0)
return rc;
/* Set i2c device register sub-address */
rc = stk1160_write_reg(dev, STK1160_SBUSR_RA, reg);
if (rc < 0)
return rc;
/* Start read now */
rc = stk1160_write_reg(dev, STK1160_SICTL, 0x20);
if (rc < 0)
return rc;
rc = stk1160_i2c_busy_wait(dev, 0x01);
if (rc < 0)
return rc;
rc = stk1160_read_reg(dev, STK1160_SBUSR_RD, value);
if (rc < 0)
return rc;
return 0;
}
/*
* stk1160_i2c_check_for_device()
* check if there is a i2c_device at the supplied address
*/
static int stk1160_i2c_check_for_device(struct stk1160 *dev,
unsigned char addr)
{
int rc;
/* Set serial device address */
rc = stk1160_write_reg(dev, STK1160_SICTL_SDA, addr);
if (rc < 0)
return rc;
/* Set device sub-address, we'll chip version reg */
rc = stk1160_write_reg(dev, STK1160_SBUSR_RA, 0x00);
if (rc < 0)
return rc;
/* Start read now */
rc = stk1160_write_reg(dev, STK1160_SICTL, 0x20);
if (rc < 0)
return rc;
rc = stk1160_i2c_busy_wait(dev, 0x01);
if (rc < 0)
return -ENODEV;
return 0;
}
/*
* stk1160_i2c_xfer()
* the main i2c transfer function
*/
static int stk1160_i2c_xfer(struct i2c_adapter *i2c_adap,
struct i2c_msg msgs[], int num)
{
struct stk1160 *dev = i2c_adap->algo_data;
int addr, rc, i;
for (i = 0; i < num; i++) {
addr = msgs[i].addr << 1;
dprintk_i2c("%s: addr=%x", __func__, addr);
if (!msgs[i].len) {
/* no len: check only for device presence */
rc = stk1160_i2c_check_for_device(dev, addr);
if (rc < 0) {
dprintk_i2c(" no device\n");
return rc;
}
} else if (msgs[i].flags & I2C_M_RD) {
/* read request without preceding register selection */
dprintk_i2c(" subaddr not selected");
rc = -EOPNOTSUPP;
goto err;
} else if (i + 1 < num && msgs[i].len <= 2 &&
(msgs[i + 1].flags & I2C_M_RD) &&
msgs[i].addr == msgs[i + 1].addr) {
if (msgs[i].len != 1 || msgs[i + 1].len != 1) {
dprintk_i2c(" len not supported");
rc = -EOPNOTSUPP;
goto err;
}
dprintk_i2c(" subaddr=%x", msgs[i].buf[0]);
rc = stk1160_i2c_read_reg(dev, addr, msgs[i].buf[0],
msgs[i + 1].buf);
dprintk_i2c(" read=%x", *msgs[i + 1].buf);
/* consumed two msgs, so we skip one of them */
i++;
} else {
if (msgs[i].len != 2) {
dprintk_i2c(" len not supported");
rc = -EOPNOTSUPP;
goto err;
}
dprintk_i2c(" subaddr=%x write=%x",
msgs[i].buf[0], msgs[i].buf[1]);
rc = stk1160_i2c_write_reg(dev, addr, msgs[i].buf[0],
msgs[i].buf[1]);
}
if (rc < 0)
goto err;
dprintk_i2c(" OK\n");
}
return num;
err:
dprintk_i2c(" ERROR: %d\n", rc);
return num;
}
/*
* functionality(), what da heck is this?
*/
static u32 functionality(struct i2c_adapter *adap)
{
return I2C_FUNC_SMBUS_EMUL;
}
static const struct i2c_algorithm algo = {
.master_xfer = stk1160_i2c_xfer,
.functionality = functionality,
};
static const struct i2c_adapter adap_template = {
.owner = THIS_MODULE,
.name = "stk1160",
.algo = &algo,
};
static const struct i2c_client client_template = {
.name = "stk1160 internal",
};
/*
* stk1160_i2c_register()
* register i2c bus
*/
int stk1160_i2c_register(struct stk1160 *dev)
{
int rc;
dev->i2c_adap = adap_template;
dev->i2c_adap.dev.parent = dev->dev;
strcpy(dev->i2c_adap.name, "stk1160");
dev->i2c_adap.algo_data = dev;
i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev);
rc = i2c_add_adapter(&dev->i2c_adap);
if (rc < 0) {
stk1160_err("cannot add i2c adapter (%d)\n", rc);
return rc;
}
dev->i2c_client = client_template;
dev->i2c_client.adapter = &dev->i2c_adap;
/* Set i2c clock divider device address */
stk1160_write_reg(dev, STK1160_SICTL_CD, 0x0f);
/* ??? */
stk1160_write_reg(dev, STK1160_ASIC + 3, 0x00);
return 0;
}
/*
* stk1160_i2c_unregister()
* unregister i2c_bus
*/
int stk1160_i2c_unregister(struct stk1160 *dev)
{
i2c_del_adapter(&dev->i2c_adap);
return 0;
}
|
