usbvision-i2c.c revision 2a7e9a260ede3b17b5bc25c540a033a45bbf0461
1/*
2 * I2C_ALGO_USB.C
3 *  i2c algorithm for USB-I2C Bridges
4 *
5 * Copyright (c) 1999-2005 Joerg Heckenbach <joerg@heckenbach-aw.de>
6 *                         Dwaine Garden <dwainegarden@rogers.com>
7 *
8 * This module is part of usbvision driver project.
9 * Updates to driver completed by Dwaine P. Garden
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 */
25
26
27#include <linux/kernel.h>
28#include <linux/module.h>
29#include <linux/delay.h>
30#include <linux/slab.h>
31#include <linux/version.h>
32#include <linux/utsname.h>
33#include <linux/init.h>
34#include <asm/uaccess.h>
35#include <linux/ioport.h>
36#include <linux/errno.h>
37#include <linux/sched.h>
38#include <linux/usb.h>
39#include <linux/i2c.h>
40#include "usbvision.h"
41
42#define DBG_I2C		1<<0
43#define DBG_ALGO	1<<1
44
45static int i2c_debug = 0;
46
47module_param (i2c_debug, int, 0644);			// debug_i2c_usb mode of the device driver
48MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
49
50#define PDEBUG(level, fmt, args...) \
51		if (i2c_debug & (level)) info("[%s:%d] " fmt, __PRETTY_FUNCTION__, __LINE__ , ## args)
52
53static int usbvision_i2c_write(void *data, unsigned char addr, char *buf,
54			    short len);
55static int usbvision_i2c_read(void *data, unsigned char addr, char *buf,
56			   short len);
57
58static inline int try_write_address(struct i2c_adapter *i2c_adap,
59				    unsigned char addr, int retries)
60{
61	struct i2c_algo_usb_data *adap = i2c_adap->algo_data;
62	void *data;
63	int i, ret = -1;
64	char buf[4];
65
66	data = i2c_get_adapdata(i2c_adap);
67	buf[0] = 0x00;
68	for (i = 0; i <= retries; i++) {
69		ret = (usbvision_i2c_write(data, addr, buf, 1));
70		if (ret == 1)
71			break;	/* success! */
72		udelay(5 /*adap->udelay */ );
73		if (i == retries)	/* no success */
74			break;
75		udelay(adap->udelay);
76	}
77	if (i) {
78		PDEBUG(DBG_ALGO,"Needed %d retries for address %#2x", i, addr);
79		PDEBUG(DBG_ALGO,"Maybe there's no device at this address");
80	}
81	return ret;
82}
83
84static inline int try_read_address(struct i2c_adapter *i2c_adap,
85				   unsigned char addr, int retries)
86{
87	struct i2c_algo_usb_data *adap = i2c_adap->algo_data;
88	void *data;
89	int i, ret = -1;
90	char buf[4];
91
92	data = i2c_get_adapdata(i2c_adap);
93	for (i = 0; i <= retries; i++) {
94		ret = (usbvision_i2c_read(data, addr, buf, 1));
95		if (ret == 1)
96			break;	/* success! */
97		udelay(5 /*adap->udelay */ );
98		if (i == retries)	/* no success */
99			break;
100		udelay(adap->udelay);
101	}
102	if (i) {
103		PDEBUG(DBG_ALGO,"Needed %d retries for address %#2x", i, addr);
104		PDEBUG(DBG_ALGO,"Maybe there's no device at this address");
105	}
106	return ret;
107}
108
109static inline int usb_find_address(struct i2c_adapter *i2c_adap,
110				   struct i2c_msg *msg, int retries,
111				   unsigned char *add)
112{
113	unsigned short flags = msg->flags;
114
115	unsigned char addr;
116	int ret;
117	if ((flags & I2C_M_TEN)) {
118		/* a ten bit address */
119		addr = 0xf0 | ((msg->addr >> 7) & 0x03);
120		/* try extended address code... */
121		ret = try_write_address(i2c_adap, addr, retries);
122		if (ret != 1) {
123			err("died at extended address code, while writing");
124			return -EREMOTEIO;
125		}
126		add[0] = addr;
127		if (flags & I2C_M_RD) {
128			/* okay, now switch into reading mode */
129			addr |= 0x01;
130			ret = try_read_address(i2c_adap, addr, retries);
131			if (ret != 1) {
132				err("died at extended address code, while reading");
133				return -EREMOTEIO;
134			}
135		}
136
137	} else {		/* normal 7bit address  */
138		addr = (msg->addr << 1);
139		if (flags & I2C_M_RD)
140			addr |= 1;
141		if (flags & I2C_M_REV_DIR_ADDR)
142			addr ^= 1;
143
144		add[0] = addr;
145		if (flags & I2C_M_RD)
146			ret = try_read_address(i2c_adap, addr, retries);
147		else
148			ret = try_write_address(i2c_adap, addr, retries);
149
150		if (ret != 1) {
151			return -EREMOTEIO;
152		}
153	}
154	return 0;
155}
156
157static int
158usb_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
159{
160	struct i2c_msg *pmsg;
161	void *data;
162	int i, ret;
163	unsigned char addr;
164
165	data = i2c_get_adapdata(i2c_adap);
166
167	for (i = 0; i < num; i++) {
168		pmsg = &msgs[i];
169		ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
170		if (ret != 0) {
171			PDEBUG(DBG_ALGO,"got NAK from device, message #%d", i);
172			return (ret < 0) ? ret : -EREMOTEIO;
173		}
174
175		if (pmsg->flags & I2C_M_RD) {
176			/* read bytes into buffer */
177			ret = (usbvision_i2c_read(data, addr, pmsg->buf, pmsg->len));
178			if (ret < pmsg->len) {
179				return (ret < 0) ? ret : -EREMOTEIO;
180			}
181		} else {
182			/* write bytes from buffer */
183			ret = (usbvision_i2c_write(data, addr, pmsg->buf, pmsg->len));
184			if (ret < pmsg->len) {
185				return (ret < 0) ? ret : -EREMOTEIO;
186			}
187		}
188	}
189	return num;
190}
191
192static int algo_control(struct i2c_adapter *adapter, unsigned int cmd, unsigned long arg)
193{
194	return 0;
195}
196
197static u32 usb_func(struct i2c_adapter *adap)
198{
199	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING;
200}
201
202
203/* -----exported algorithm data: -------------------------------------	*/
204
205static struct i2c_algorithm i2c_usb_algo = {
206	.master_xfer   = usb_xfer,
207	.smbus_xfer    = NULL,
208	.algo_control  = algo_control,
209	.functionality = usb_func,
210};
211
212
213/*
214 * registering functions to load algorithms at runtime
215 */
216int usbvision_i2c_usb_add_bus(struct i2c_adapter *adap)
217{
218	PDEBUG(DBG_I2C, "I2C   debugging is enabled [i2c]");
219	PDEBUG(DBG_ALGO, "ALGO   debugging is enabled [i2c]");
220
221	/* register new adapter to i2c module... */
222
223	adap->algo = &i2c_usb_algo;
224
225	adap->timeout = 100;	/* default values, should       */
226	adap->retries = 3;	/* be replaced by defines       */
227
228	i2c_add_adapter(adap);
229
230	PDEBUG(DBG_ALGO,"i2c bus for %s registered", adap->name);
231
232	return 0;
233}
234
235
236int usbvision_i2c_usb_del_bus(struct i2c_adapter *adap)
237{
238
239	i2c_del_adapter(adap);
240
241	PDEBUG(DBG_ALGO,"i2c bus for %s unregistered", adap->name);
242
243	return 0;
244}
245
246
247/* ----------------------------------------------------------------------- */
248/* usbvision specific I2C functions                                        */
249/* ----------------------------------------------------------------------- */
250static struct i2c_adapter i2c_adap_template;
251static struct i2c_algo_usb_data i2c_algo_template;
252static struct i2c_client i2c_client_template;
253
254int usbvision_init_i2c(struct usb_usbvision *usbvision)
255{
256	memcpy(&usbvision->i2c_adap, &i2c_adap_template,
257	       sizeof(struct i2c_adapter));
258	memcpy(&usbvision->i2c_algo, &i2c_algo_template,
259	       sizeof(struct i2c_algo_usb_data));
260	memcpy(&usbvision->i2c_client, &i2c_client_template,
261	       sizeof(struct i2c_client));
262
263	sprintf(usbvision->i2c_adap.name + strlen(usbvision->i2c_adap.name),
264		" #%d", usbvision->vdev->minor & 0x1f);
265	PDEBUG(DBG_I2C,"Adaptername: %s", usbvision->i2c_adap.name);
266
267	i2c_set_adapdata(&usbvision->i2c_adap, usbvision);
268	i2c_set_clientdata(&usbvision->i2c_client, usbvision);
269	i2c_set_algo_usb_data(&usbvision->i2c_algo, usbvision);
270
271	usbvision->i2c_adap.algo_data = &usbvision->i2c_algo;
272	usbvision->i2c_client.adapter = &usbvision->i2c_adap;
273
274	if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
275		printk(KERN_ERR "usbvision_init_i2c: can't write reg\n");
276		return -EBUSY;
277	}
278
279#ifdef CONFIG_MODULES
280	/* Request the load of the i2c modules we need */
281	switch (usbvision_device_data[usbvision->DevModel].Codec) {
282	case CODEC_SAA7113:
283		request_module("saa7115");
284		break;
285	case CODEC_SAA7111:
286		request_module("saa7115");
287		break;
288	}
289	if (usbvision_device_data[usbvision->DevModel].Tuner == 1) {
290		request_module("tuner");
291	}
292#endif
293
294	return usbvision_i2c_usb_add_bus(&usbvision->i2c_adap);
295}
296
297void call_i2c_clients(struct usb_usbvision *usbvision, unsigned int cmd,
298		      void *arg)
299{
300	BUG_ON(NULL == usbvision->i2c_adap.algo_data);
301	i2c_clients_command(&usbvision->i2c_adap, cmd, arg);
302}
303
304static int attach_inform(struct i2c_client *client)
305{
306	struct usb_usbvision *usbvision;
307
308	usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
309
310	switch (client->addr << 1) {
311		case 0x43:
312		case 0x4b:
313		{
314			struct tuner_setup tun_setup;
315
316			tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
317			tun_setup.type = TUNER_TDA9887;
318			tun_setup.addr = client->addr;
319
320			call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
321
322			break;
323		}
324		case 0x42:
325			PDEBUG(DBG_I2C,"attach_inform: saa7114 detected.");
326			break;
327		case 0x4a:
328			PDEBUG(DBG_I2C,"attach_inform: saa7113 detected.");
329			break;
330		case 0xa0:
331			PDEBUG(DBG_I2C,"attach_inform: eeprom detected.");
332			break;
333
334		default:
335			{
336				struct tuner_setup tun_setup;
337
338				PDEBUG(DBG_I2C,"attach inform: detected I2C address %x", client->addr << 1);
339				usbvision->tuner_addr = client->addr;
340
341				if ((usbvision->have_tuner) && (usbvision->tuner_type != -1)) {
342					tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
343					tun_setup.type = usbvision->tuner_type;
344					tun_setup.addr = usbvision->tuner_addr;
345					call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
346				}
347			}
348			break;
349	}
350	return 0;
351}
352
353static int detach_inform(struct i2c_client *client)
354{
355	struct usb_usbvision *usbvision;
356
357	usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
358
359	PDEBUG(DBG_I2C,"usbvision[%d] detaches %s", usbvision->nr, client->name);
360	return 0;
361}
362
363static int
364usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
365		     char *buf, short len)
366{
367	int rc, retries;
368
369	for (retries = 5;;) {
370		rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
371		if (rc < 0)
372			return rc;
373
374		/* Initiate byte read cycle                    */
375		/* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
376		/*                    d3 0=Wr 1=Rd             */
377		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
378				      (len & 0x07) | 0x18);
379		if (rc < 0)
380			return rc;
381
382		/* Test for Busy and ACK */
383		do {
384			/* USBVISION_SER_CONT -> d4 == 0 busy */
385			rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
386		} while (rc > 0 && ((rc & 0x10) != 0));	/* Retry while busy */
387		if (rc < 0)
388			return rc;
389
390		/* USBVISION_SER_CONT -> d5 == 1 Not ack */
391		if ((rc & 0x20) == 0)	/* Ack? */
392			break;
393
394		/* I2C abort */
395		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
396		if (rc < 0)
397			return rc;
398
399		if (--retries < 0)
400			return -1;
401	}
402
403	switch (len) {
404	case 4:
405		buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
406	case 3:
407		buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
408	case 2:
409		buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
410	case 1:
411		buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
412		break;
413	default:
414		printk(KERN_ERR
415		       "usbvision_i2c_read_max4: buffer length > 4\n");
416	}
417
418	if (i2c_debug & DBG_I2C) {
419		int idx;
420		for (idx = 0; idx < len; idx++) {
421			PDEBUG(DBG_I2C,"read %x from address %x", (unsigned char)buf[idx], addr);
422		}
423	}
424	return len;
425}
426
427
428static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
429				 unsigned char addr, const char *buf,
430				 short len)
431{
432	int rc, retries;
433	int i;
434	unsigned char value[6];
435	unsigned char ser_cont;
436
437	ser_cont = (len & 0x07) | 0x10;
438
439	value[0] = addr;
440	value[1] = ser_cont;
441	for (i = 0; i < len; i++)
442		value[i + 2] = buf[i];
443
444	for (retries = 5;;) {
445		rc = usb_control_msg(usbvision->dev,
446				     usb_sndctrlpipe(usbvision->dev, 1),
447				     USBVISION_OP_CODE,
448				     USB_DIR_OUT | USB_TYPE_VENDOR |
449				     USB_RECIP_ENDPOINT, 0,
450				     (__u16) USBVISION_SER_ADRS, value,
451				     len + 2, HZ);
452
453		if (rc < 0)
454			return rc;
455
456		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
457				      (len & 0x07) | 0x10);
458		if (rc < 0)
459			return rc;
460
461		/* Test for Busy and ACK */
462		do {
463			rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
464		} while (rc > 0 && ((rc & 0x10) != 0));	/* Retry while busy */
465		if (rc < 0)
466			return rc;
467
468		if ((rc & 0x20) == 0)	/* Ack? */
469			break;
470
471		/* I2C abort */
472		usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
473
474		if (--retries < 0)
475			return -1;
476
477	}
478
479	if (i2c_debug & DBG_I2C) {
480		int idx;
481		for (idx = 0; idx < len; idx++) {
482			PDEBUG(DBG_I2C,"wrote %x at address %x", (unsigned char)buf[idx], addr);
483		}
484	}
485	return len;
486}
487
488static int usbvision_i2c_write(void *data, unsigned char addr, char *buf,
489			    short len)
490{
491	char *bufPtr = buf;
492	int retval;
493	int wrcount = 0;
494	int count;
495	int maxLen = 4;
496	struct usb_usbvision *usbvision = (struct usb_usbvision *) data;
497
498	while (len > 0) {
499		count = (len > maxLen) ? maxLen : len;
500		retval = usbvision_i2c_write_max4(usbvision, addr, bufPtr, count);
501		if (retval > 0) {
502			len -= count;
503			bufPtr += count;
504			wrcount += count;
505		} else
506			return (retval < 0) ? retval : -EFAULT;
507	}
508	return wrcount;
509}
510
511static int usbvision_i2c_read(void *data, unsigned char addr, char *buf,
512			   short len)
513{
514	char temp[4];
515	int retval, i;
516	int rdcount = 0;
517	int count;
518	struct usb_usbvision *usbvision = (struct usb_usbvision *) data;
519
520	while (len > 0) {
521		count = (len > 3) ? 4 : len;
522		retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
523		if (retval > 0) {
524			for (i = 0; i < len; i++)
525				buf[rdcount + i] = temp[i];
526			len -= count;
527			rdcount += count;
528		} else
529			return (retval < 0) ? retval : -EFAULT;
530	}
531	return rdcount;
532}
533
534static struct i2c_algo_usb_data i2c_algo_template = {
535	.data		= NULL,
536	.inb		= usbvision_i2c_read,
537	.outb		= usbvision_i2c_write,
538	.udelay		= 10,
539	.mdelay		= 10,
540	.timeout	= 100,
541};
542
543static struct i2c_adapter i2c_adap_template = {
544	.owner = THIS_MODULE,
545	.name              = "usbvision",
546	.id                = I2C_HW_B_BT848, /* FIXME */
547	.algo              = NULL,
548	.algo_data         = NULL,
549	.client_register   = attach_inform,
550	.client_unregister = detach_inform,
551#ifdef I2C_ADAP_CLASS_TV_ANALOG
552	.class             = I2C_ADAP_CLASS_TV_ANALOG,
553#else
554	.class		   = I2C_CLASS_TV_ANALOG,
555#endif
556};
557
558static struct i2c_client i2c_client_template = {
559	.name		= "usbvision internal",
560};
561
562EXPORT_SYMBOL(usbvision_i2c_usb_add_bus);
563EXPORT_SYMBOL(usbvision_i2c_usb_del_bus);
564
565/*
566 * Overrides for Emacs so that we follow Linus's tabbing style.
567 * ---------------------------------------------------------------------------
568 * Local variables:
569 * c-basic-offset: 8
570 * End:
571 */
572