aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/media/video/usbvision/usbvision-i2c.c
blob: 05b1344181cd30568b41bebb1317f4e179e6b8af (plain) (blame)
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
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
/*
 * usbvision_i2c.c
 *  i2c algorithm for USB-I2C Bridges
 *
 * Copyright (c) 1999-2007 Joerg Heckenbach <joerg@heckenbach-aw.de>
 *                         Dwaine Garden <dwainegarden@rogers.com>
 *
 * This module is part of usbvision driver project.
 * Updates to driver completed by Dwaine P. Garden
 *
 * 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.
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */


#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/uaccess.h>
#include <linux/ioport.h>
#include <linux/errno.h>
#include <linux/usb.h>
#include <linux/i2c.h>
#include "usbvision.h"

#define DBG_I2C		(1 << 0)

static int i2c_debug;

module_param(i2c_debug, int, 0644);			/* debug_i2c_usb mode of the device driver */
MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");

#define PDEBUG(level, fmt, args...) { \
		if (i2c_debug & (level)) \
			printk(KERN_INFO KBUILD_MODNAME ":[%s:%d] " fmt, \
				__func__, __LINE__ , ## args); \
	}

static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
			    short len);
static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
			   short len);

static inline int try_write_address(struct i2c_adapter *i2c_adap,
				    unsigned char addr, int retries)
{
	struct usb_usbvision *usbvision;
	int i, ret = -1;
	char buf[4];

	usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
	buf[0] = 0x00;
	for (i = 0; i <= retries; i++) {
		ret = (usbvision_i2c_write(usbvision, addr, buf, 1));
		if (ret == 1)
			break;	/* success! */
		udelay(5);
		if (i == retries)	/* no success */
			break;
		udelay(10);
	}
	if (i) {
		PDEBUG(DBG_I2C, "Needed %d retries for address %#2x", i, addr);
		PDEBUG(DBG_I2C, "Maybe there's no device at this address");
	}
	return ret;
}

static inline int try_read_address(struct i2c_adapter *i2c_adap,
				   unsigned char addr, int retries)
{
	struct usb_usbvision *usbvision;
	int i, ret = -1;
	char buf[4];

	usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
	for (i = 0; i <= retries; i++) {
		ret = (usbvision_i2c_read(usbvision, addr, buf, 1));
		if (ret == 1)
			break;	/* success! */
		udelay(5);
		if (i == retries)	/* no success */
			break;
		udelay(10);
	}
	if (i) {
		PDEBUG(DBG_I2C, "Needed %d retries for address %#2x", i, addr);
		PDEBUG(DBG_I2C, "Maybe there's no device at this address");
	}
	return ret;
}

static inline int usb_find_address(struct i2c_adapter *i2c_adap,
				   struct i2c_msg *msg, int retries,
				   unsigned char *add)
{
	unsigned short flags = msg->flags;

	unsigned char addr;
	int ret;
	if ((flags & I2C_M_TEN)) {
		/* a ten bit address */
		addr = 0xf0 | ((msg->addr >> 7) & 0x03);
		/* try extended address code... */
		ret = try_write_address(i2c_adap, addr, retries);
		if (ret != 1) {
			dev_err(&i2c_adap->dev,
				"died at extended address code,	while writing\n");
			return -EREMOTEIO;
		}
		add[0] = addr;
		if (flags & I2C_M_RD) {
			/* okay, now switch into reading mode */
			addr |= 0x01;
			ret = try_read_address(i2c_adap, addr, retries);
			if (ret != 1) {
				dev_err(&i2c_adap->dev,
					"died at extended address code, while reading\n");
				return -EREMOTEIO;
			}
		}

	} else {		/* normal 7bit address  */
		addr = (msg->addr << 1);
		if (flags & I2C_M_RD)
			addr |= 1;

		add[0] = addr;
		if (flags & I2C_M_RD)
			ret = try_read_address(i2c_adap, addr, retries);
		else
			ret = try_write_address(i2c_adap, addr, retries);

		if (ret != 1)
			return -EREMOTEIO;
	}
	return 0;
}

static int
usbvision_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
{
	struct i2c_msg *pmsg;
	struct usb_usbvision *usbvision;
	int i, ret;
	unsigned char addr = 0;

	usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);

	for (i = 0; i < num; i++) {
		pmsg = &msgs[i];
		ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
		if (ret != 0) {
			PDEBUG(DBG_I2C, "got NAK from device, message #%d", i);
			return (ret < 0) ? ret : -EREMOTEIO;
		}

		if (pmsg->flags & I2C_M_RD) {
			/* read bytes into buffer */
			ret = (usbvision_i2c_read(usbvision, addr, pmsg->buf, pmsg->len));
			if (ret < pmsg->len)
				return (ret < 0) ? ret : -EREMOTEIO;
		} else {
			/* write bytes from buffer */
			ret = (usbvision_i2c_write(usbvision, addr, pmsg->buf, pmsg->len));
			if (ret < pmsg->len)
				return (ret < 0) ? ret : -EREMOTEIO;
		}
	}
	return num;
}

static u32 functionality(struct i2c_adapter *adap)
{
	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
}

/* -----exported algorithm data: -------------------------------------	*/

static struct i2c_algorithm usbvision_algo = {
	.master_xfer   = usbvision_i2c_xfer,
	.smbus_xfer    = NULL,
	.functionality = functionality,
};


/* ----------------------------------------------------------------------- */
/* usbvision specific I2C functions                                        */
/* ----------------------------------------------------------------------- */
static struct i2c_adapter i2c_adap_template;

int usbvision_i2c_register(struct usb_usbvision *usbvision)
{
	static unsigned short saa711x_addrs[] = {
		0x4a >> 1, 0x48 >> 1,	/* SAA7111, SAA7111A and SAA7113 */
		0x42 >> 1, 0x40 >> 1,	/* SAA7114, SAA7115 and SAA7118 */
		I2C_CLIENT_END };

	if (usbvision->registered_i2c)
		return 0;

	memcpy(&usbvision->i2c_adap, &i2c_adap_template,
	       sizeof(struct i2c_adapter));

	sprintf(usbvision->i2c_adap.name, "%s-%d-%s", i2c_adap_template.name,
		usbvision->dev->bus->busnum, usbvision->dev->devpath);
	PDEBUG(DBG_I2C, "Adaptername: %s", usbvision->i2c_adap.name);
	usbvision->i2c_adap.dev.parent = &usbvision->dev->dev;

	i2c_set_adapdata(&usbvision->i2c_adap, &usbvision->v4l2_dev);

	if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
		printk(KERN_ERR "usbvision_register: can't write reg\n");
		return -EBUSY;
	}

	PDEBUG(DBG_I2C, "I2C   debugging is enabled [i2c]");
	PDEBUG(DBG_I2C, "ALGO   debugging is enabled [i2c]");

	/* register new adapter to i2c module... */

	usbvision->i2c_adap.algo = &usbvision_algo;

	usbvision->i2c_adap.timeout = 100;	/* default values, should       */
	usbvision->i2c_adap.retries = 3;	/* be replaced by defines       */

	i2c_add_adapter(&usbvision->i2c_adap);

	PDEBUG(DBG_I2C, "i2c bus for %s registered", usbvision->i2c_adap.name);

	/* Request the load of the i2c modules we need */
	switch (usbvision_device_data[usbvision->dev_model].codec) {
	case CODEC_SAA7113:
	case CODEC_SAA7111:
		/* Without this delay the detection of the saa711x is
		   hit-and-miss. */
		mdelay(10);
		v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
				&usbvision->i2c_adap,
				"saa7115_auto", 0, saa711x_addrs);
		break;
	}
	if (usbvision_device_data[usbvision->dev_model].tuner == 1) {
		struct v4l2_subdev *sd;
		enum v4l2_i2c_tuner_type type;
		struct tuner_setup tun_setup;

		sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
				&usbvision->i2c_adap,
				"tuner", 0, v4l2_i2c_tuner_addrs(ADDRS_DEMOD));
		/* depending on whether we found a demod or not, select
		   the tuner type. */
		type = sd ? ADDRS_TV_WITH_DEMOD : ADDRS_TV;

		sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
				&usbvision->i2c_adap,
				"tuner", 0, v4l2_i2c_tuner_addrs(type));

		if (sd == NULL)
			return -ENODEV;
		if (usbvision->tuner_type != -1) {
			tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
			tun_setup.type = usbvision->tuner_type;
			tun_setup.addr = v4l2_i2c_subdev_addr(sd);
			call_all(usbvision, tuner, s_type_addr, &tun_setup);
		}
	}
	usbvision->registered_i2c = 1;

	return 0;
}

int usbvision_i2c_unregister(struct usb_usbvision *usbvision)
{
	if (!usbvision->registered_i2c)
		return 0;

	i2c_del_adapter(&(usbvision->i2c_adap));
	usbvision->registered_i2c = 0;

	PDEBUG(DBG_I2C, "i2c bus for %s unregistered", usbvision->i2c_adap.name);

	return 0;
}

static int
usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
		     char *buf, short len)
{
	int rc, retries;

	for (retries = 5;;) {
		rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
		if (rc < 0)
			return rc;

		/* Initiate byte read cycle                    */
		/* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
		/*                    d3 0=Wr 1=Rd             */
		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
				      (len & 0x07) | 0x18);
		if (rc < 0)
			return rc;

		/* Test for Busy and ACK */
		do {
			/* USBVISION_SER_CONT -> d4 == 0 busy */
			rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
		} while (rc > 0 && ((rc & 0x10) != 0));	/* Retry while busy */
		if (rc < 0)
			return rc;

		/* USBVISION_SER_CONT -> d5 == 1 Not ack */
		if ((rc & 0x20) == 0)	/* Ack? */
			break;

		/* I2C abort */
		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
		if (rc < 0)
			return rc;

		if (--retries < 0)
			return -1;
	}

	switch (len) {
	case 4:
		buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
	case 3:
		buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
	case 2:
		buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
	case 1:
		buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
		break;
	default:
		printk(KERN_ERR
		       "usbvision_i2c_read_max4: buffer length > 4\n");
	}

	if (i2c_debug & DBG_I2C) {
		int idx;

		for (idx = 0; idx < len; idx++)
			PDEBUG(DBG_I2C, "read %x from address %x", (unsigned char)buf[idx], addr);
	}
	return len;
}


static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
				 unsigned char addr, const char *buf,
				 short len)
{
	int rc, retries;
	int i;
	unsigned char value[6];
	unsigned char ser_cont;

	ser_cont = (len & 0x07) | 0x10;

	value[0] = addr;
	value[1] = ser_cont;
	for (i = 0; i < len; i++)
		value[i + 2] = buf[i];

	for (retries = 5;;) {
		rc = usb_control_msg(usbvision->dev,
				     usb_sndctrlpipe(usbvision->dev, 1),
				     USBVISION_OP_CODE,
				     USB_DIR_OUT | USB_TYPE_VENDOR |
				     USB_RECIP_ENDPOINT, 0,
				     (__u16) USBVISION_SER_ADRS, value,
				     len + 2, HZ);

		if (rc < 0)
			return rc;

		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
				      (len & 0x07) | 0x10);
		if (rc < 0)
			return rc;

		/* Test for Busy and ACK */
		do {
			rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
		} while (rc > 0 && ((rc & 0x10) != 0));	/* Retry while busy */
		if (rc < 0)
			return rc;

		if ((rc & 0x20) == 0)	/* Ack? */
			break;

		/* I2C abort */
		usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);

		if (--retries < 0)
			return -1;

	}

	if (i2c_debug & DBG_I2C) {
		int idx;

		for (idx = 0; idx < len; idx++)
			PDEBUG(DBG_I2C, "wrote %x at address %x", (unsigned char)buf[idx], addr);
	}
	return len;
}

static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
			    short len)
{
	char *buf_ptr = buf;
	int retval;
	int wrcount = 0;
	int count;
	int max_len = 4;

	while (len > 0) {
		count = (len > max_len) ? max_len : len;
		retval = usbvision_i2c_write_max4(usbvision, addr, buf_ptr, count);
		if (retval > 0) {
			len -= count;
			buf_ptr += count;
			wrcount += count;
		} else
			return (retval < 0) ? retval : -EFAULT;
	}
	return wrcount;
}

static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
			   short len)
{
	char temp[4];
	int retval, i;
	int rdcount = 0;
	int count;

	while (len > 0) {
		count = (len > 3) ? 4 : len;
		retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
		if (retval > 0) {
			for (i = 0; i < len; i++)
				buf[rdcount + i] = temp[i];
			len -= count;
			rdcount += count;
		} else
			return (retval < 0) ? retval : -EFAULT;
	}
	return rdcount;
}

static struct i2c_adapter i2c_adap_template = {
	.owner = THIS_MODULE,
	.name              = "usbvision",
};

/*
 * Overrides for Emacs so that we follow Linus's tabbing style.
 * ---------------------------------------------------------------------------
 * Local variables:
 * c-basic-offset: 8
 * End:
 */