usbvision-i2c.c revision 12a917f69d1468c91d646dbad8408dd0d39d6207
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	void *data;
62	int i, ret = -1;
63	char buf[4];
64
65	data = i2c_get_adapdata(i2c_adap);
66	buf[0] = 0x00;
67	for (i = 0; i <= retries; i++) {
68		ret = (usbvision_i2c_write(data, addr, buf, 1));
69		if (ret == 1)
70			break;	/* success! */
71		udelay(5);
72		if (i == retries)	/* no success */
73			break;
74		udelay(10);
75	}
76	if (i) {
77		PDEBUG(DBG_ALGO,"Needed %d retries for address %#2x", i, addr);
78		PDEBUG(DBG_ALGO,"Maybe there's no device at this address");
79	}
80	return ret;
81}
82
83static inline int try_read_address(struct i2c_adapter *i2c_adap,
84				   unsigned char addr, int retries)
85{
86	void *data;
87	int i, ret = -1;
88	char buf[4];
89
90	data = i2c_get_adapdata(i2c_adap);
91	for (i = 0; i <= retries; i++) {
92		ret = (usbvision_i2c_read(data, addr, buf, 1));
93		if (ret == 1)
94			break;	/* success! */
95		udelay(5);
96		if (i == retries)	/* no success */
97			break;
98		udelay(10);
99	}
100	if (i) {
101		PDEBUG(DBG_ALGO,"Needed %d retries for address %#2x", i, addr);
102		PDEBUG(DBG_ALGO,"Maybe there's no device at this address");
103	}
104	return ret;
105}
106
107static inline int usb_find_address(struct i2c_adapter *i2c_adap,
108				   struct i2c_msg *msg, int retries,
109				   unsigned char *add)
110{
111	unsigned short flags = msg->flags;
112
113	unsigned char addr;
114	int ret;
115	if ((flags & I2C_M_TEN)) {
116		/* a ten bit address */
117		addr = 0xf0 | ((msg->addr >> 7) & 0x03);
118		/* try extended address code... */
119		ret = try_write_address(i2c_adap, addr, retries);
120		if (ret != 1) {
121			err("died at extended address code, while writing");
122			return -EREMOTEIO;
123		}
124		add[0] = addr;
125		if (flags & I2C_M_RD) {
126			/* okay, now switch into reading mode */
127			addr |= 0x01;
128			ret = try_read_address(i2c_adap, addr, retries);
129			if (ret != 1) {
130				err("died at extended address code, while reading");
131				return -EREMOTEIO;
132			}
133		}
134
135	} else {		/* normal 7bit address  */
136		addr = (msg->addr << 1);
137		if (flags & I2C_M_RD)
138			addr |= 1;
139		if (flags & I2C_M_REV_DIR_ADDR)
140			addr ^= 1;
141
142		add[0] = addr;
143		if (flags & I2C_M_RD)
144			ret = try_read_address(i2c_adap, addr, retries);
145		else
146			ret = try_write_address(i2c_adap, addr, retries);
147
148		if (ret != 1) {
149			return -EREMOTEIO;
150		}
151	}
152	return 0;
153}
154
155static int
156usb_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
157{
158	struct i2c_msg *pmsg;
159	void *data;
160	int i, ret;
161	unsigned char addr;
162
163	data = i2c_get_adapdata(i2c_adap);
164
165	for (i = 0; i < num; i++) {
166		pmsg = &msgs[i];
167		ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
168		if (ret != 0) {
169			PDEBUG(DBG_ALGO,"got NAK from device, message #%d", i);
170			return (ret < 0) ? ret : -EREMOTEIO;
171		}
172
173		if (pmsg->flags & I2C_M_RD) {
174			/* read bytes into buffer */
175			ret = (usbvision_i2c_read(data, addr, pmsg->buf, pmsg->len));
176			if (ret < pmsg->len) {
177				return (ret < 0) ? ret : -EREMOTEIO;
178			}
179		} else {
180			/* write bytes from buffer */
181			ret = (usbvision_i2c_write(data, addr, pmsg->buf, pmsg->len));
182			if (ret < pmsg->len) {
183				return (ret < 0) ? ret : -EREMOTEIO;
184			}
185		}
186	}
187	return num;
188}
189
190static int algo_control(struct i2c_adapter *adapter, unsigned int cmd, unsigned long arg)
191{
192	return 0;
193}
194
195static u32 usb_func(struct i2c_adapter *adap)
196{
197	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING;
198}
199
200
201/* -----exported algorithm data: -------------------------------------	*/
202
203static struct i2c_algorithm i2c_usb_algo = {
204	.master_xfer   = usb_xfer,
205	.smbus_xfer    = NULL,
206	.algo_control  = algo_control,
207	.functionality = usb_func,
208};
209
210
211/*
212 * registering functions to load algorithms at runtime
213 */
214static int usbvision_i2c_usb_add_bus(struct i2c_adapter *adap)
215{
216	PDEBUG(DBG_I2C, "I2C   debugging is enabled [i2c]");
217	PDEBUG(DBG_ALGO, "ALGO   debugging is enabled [i2c]");
218
219	/* register new adapter to i2c module... */
220
221	adap->algo = &i2c_usb_algo;
222
223	adap->timeout = 100;	/* default values, should       */
224	adap->retries = 3;	/* be replaced by defines       */
225
226	i2c_add_adapter(adap);
227
228	PDEBUG(DBG_ALGO,"i2c bus for %s registered", adap->name);
229
230	return 0;
231}
232
233
234int usbvision_i2c_usb_del_bus(struct i2c_adapter *adap)
235{
236
237	i2c_del_adapter(adap);
238
239	PDEBUG(DBG_ALGO,"i2c bus for %s unregistered", adap->name);
240
241	return 0;
242}
243
244
245/* ----------------------------------------------------------------------- */
246/* usbvision specific I2C functions                                        */
247/* ----------------------------------------------------------------------- */
248static struct i2c_adapter i2c_adap_template;
249static struct i2c_client i2c_client_template;
250
251int usbvision_init_i2c(struct usb_usbvision *usbvision)
252{
253	memcpy(&usbvision->i2c_adap, &i2c_adap_template,
254	       sizeof(struct i2c_adapter));
255	memcpy(&usbvision->i2c_client, &i2c_client_template,
256	       sizeof(struct i2c_client));
257
258	sprintf(usbvision->i2c_adap.name + strlen(usbvision->i2c_adap.name),
259		" #%d", usbvision->vdev->minor & 0x1f);
260	PDEBUG(DBG_I2C,"Adaptername: %s", usbvision->i2c_adap.name);
261	usbvision->i2c_adap.dev.parent = &usbvision->dev->dev;
262
263	i2c_set_adapdata(&usbvision->i2c_adap, usbvision);
264	i2c_set_clientdata(&usbvision->i2c_client, usbvision);
265
266	usbvision->i2c_client.adapter = &usbvision->i2c_adap;
267
268	if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
269		printk(KERN_ERR "usbvision_init_i2c: can't write reg\n");
270		return -EBUSY;
271	}
272
273#ifdef CONFIG_MODULES
274	/* Request the load of the i2c modules we need */
275	switch (usbvision_device_data[usbvision->DevModel].Codec) {
276	case CODEC_SAA7113:
277		request_module("saa7115");
278		break;
279	case CODEC_SAA7111:
280		request_module("saa7115");
281		break;
282	}
283	if (usbvision_device_data[usbvision->DevModel].Tuner == 1) {
284		request_module("tuner");
285	}
286#endif
287
288	return usbvision_i2c_usb_add_bus(&usbvision->i2c_adap);
289}
290
291void call_i2c_clients(struct usb_usbvision *usbvision, unsigned int cmd,
292		      void *arg)
293{
294	i2c_clients_command(&usbvision->i2c_adap, cmd, arg);
295}
296
297static int attach_inform(struct i2c_client *client)
298{
299	struct usb_usbvision *usbvision;
300
301	usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
302
303	switch (client->addr << 1) {
304		case 0x43:
305		case 0x4b:
306		{
307			struct tuner_setup tun_setup;
308
309			tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
310			tun_setup.type = TUNER_TDA9887;
311			tun_setup.addr = client->addr;
312
313			call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
314
315			break;
316		}
317		case 0x42:
318			PDEBUG(DBG_I2C,"attach_inform: saa7114 detected.");
319			break;
320		case 0x4a:
321			PDEBUG(DBG_I2C,"attach_inform: saa7113 detected.");
322			break;
323		case 0x48:
324			PDEBUG(DBG_I2C,"attach_inform: saa7111 detected.");
325			break;
326		case 0xa0:
327			PDEBUG(DBG_I2C,"attach_inform: eeprom detected.");
328			break;
329
330		default:
331			{
332				struct tuner_setup tun_setup;
333
334				PDEBUG(DBG_I2C,"attach inform: detected I2C address %x", client->addr << 1);
335				usbvision->tuner_addr = client->addr;
336
337				if ((usbvision->have_tuner) && (usbvision->tuner_type != -1)) {
338					tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
339					tun_setup.type = usbvision->tuner_type;
340					tun_setup.addr = usbvision->tuner_addr;
341					call_i2c_clients(usbvision, TUNER_SET_TYPE_ADDR, &tun_setup);
342				}
343			}
344			break;
345	}
346	return 0;
347}
348
349static int detach_inform(struct i2c_client *client)
350{
351	struct usb_usbvision *usbvision;
352
353	usbvision = (struct usb_usbvision *)i2c_get_adapdata(client->adapter);
354
355	PDEBUG(DBG_I2C,"usbvision[%d] detaches %s", usbvision->nr, client->name);
356	return 0;
357}
358
359static int
360usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
361		     char *buf, short len)
362{
363	int rc, retries;
364
365	for (retries = 5;;) {
366		rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
367		if (rc < 0)
368			return rc;
369
370		/* Initiate byte read cycle                    */
371		/* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
372		/*                    d3 0=Wr 1=Rd             */
373		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
374				      (len & 0x07) | 0x18);
375		if (rc < 0)
376			return rc;
377
378		/* Test for Busy and ACK */
379		do {
380			/* USBVISION_SER_CONT -> d4 == 0 busy */
381			rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
382		} while (rc > 0 && ((rc & 0x10) != 0));	/* Retry while busy */
383		if (rc < 0)
384			return rc;
385
386		/* USBVISION_SER_CONT -> d5 == 1 Not ack */
387		if ((rc & 0x20) == 0)	/* Ack? */
388			break;
389
390		/* I2C abort */
391		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
392		if (rc < 0)
393			return rc;
394
395		if (--retries < 0)
396			return -1;
397	}
398
399	switch (len) {
400	case 4:
401		buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
402	case 3:
403		buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
404	case 2:
405		buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
406	case 1:
407		buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
408		break;
409	default:
410		printk(KERN_ERR
411		       "usbvision_i2c_read_max4: buffer length > 4\n");
412	}
413
414	if (i2c_debug & DBG_I2C) {
415		int idx;
416		for (idx = 0; idx < len; idx++) {
417			PDEBUG(DBG_I2C,"read %x from address %x", (unsigned char)buf[idx], addr);
418		}
419	}
420	return len;
421}
422
423
424static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
425				 unsigned char addr, const char *buf,
426				 short len)
427{
428	int rc, retries;
429	int i;
430	unsigned char value[6];
431	unsigned char ser_cont;
432
433	ser_cont = (len & 0x07) | 0x10;
434
435	value[0] = addr;
436	value[1] = ser_cont;
437	for (i = 0; i < len; i++)
438		value[i + 2] = buf[i];
439
440	for (retries = 5;;) {
441		rc = usb_control_msg(usbvision->dev,
442				     usb_sndctrlpipe(usbvision->dev, 1),
443				     USBVISION_OP_CODE,
444				     USB_DIR_OUT | USB_TYPE_VENDOR |
445				     USB_RECIP_ENDPOINT, 0,
446				     (__u16) USBVISION_SER_ADRS, value,
447				     len + 2, HZ);
448
449		if (rc < 0)
450			return rc;
451
452		rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
453				      (len & 0x07) | 0x10);
454		if (rc < 0)
455			return rc;
456
457		/* Test for Busy and ACK */
458		do {
459			rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
460		} while (rc > 0 && ((rc & 0x10) != 0));	/* Retry while busy */
461		if (rc < 0)
462			return rc;
463
464		if ((rc & 0x20) == 0)	/* Ack? */
465			break;
466
467		/* I2C abort */
468		usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
469
470		if (--retries < 0)
471			return -1;
472
473	}
474
475	if (i2c_debug & DBG_I2C) {
476		int idx;
477		for (idx = 0; idx < len; idx++) {
478			PDEBUG(DBG_I2C,"wrote %x at address %x", (unsigned char)buf[idx], addr);
479		}
480	}
481	return len;
482}
483
484static int usbvision_i2c_write(void *data, unsigned char addr, char *buf,
485			    short len)
486{
487	char *bufPtr = buf;
488	int retval;
489	int wrcount = 0;
490	int count;
491	int maxLen = 4;
492	struct usb_usbvision *usbvision = (struct usb_usbvision *) data;
493
494	while (len > 0) {
495		count = (len > maxLen) ? maxLen : len;
496		retval = usbvision_i2c_write_max4(usbvision, addr, bufPtr, count);
497		if (retval > 0) {
498			len -= count;
499			bufPtr += count;
500			wrcount += count;
501		} else
502			return (retval < 0) ? retval : -EFAULT;
503	}
504	return wrcount;
505}
506
507static int usbvision_i2c_read(void *data, unsigned char addr, char *buf,
508			   short len)
509{
510	char temp[4];
511	int retval, i;
512	int rdcount = 0;
513	int count;
514	struct usb_usbvision *usbvision = (struct usb_usbvision *) data;
515
516	while (len > 0) {
517		count = (len > 3) ? 4 : len;
518		retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
519		if (retval > 0) {
520			for (i = 0; i < len; i++)
521				buf[rdcount + i] = temp[i];
522			len -= count;
523			rdcount += count;
524		} else
525			return (retval < 0) ? retval : -EFAULT;
526	}
527	return rdcount;
528}
529
530static struct i2c_adapter i2c_adap_template = {
531	.owner = THIS_MODULE,
532	.name              = "usbvision",
533	.id                = I2C_HW_B_BT848, /* FIXME */
534	.client_register   = attach_inform,
535	.client_unregister = detach_inform,
536#ifdef I2C_ADAP_CLASS_TV_ANALOG
537	.class             = I2C_ADAP_CLASS_TV_ANALOG,
538#else
539	.class		   = I2C_CLASS_TV_ANALOG,
540#endif
541};
542
543static struct i2c_client i2c_client_template = {
544	.name		= "usbvision internal",
545};
546
547/*
548 * Overrides for Emacs so that we follow Linus's tabbing style.
549 * ---------------------------------------------------------------------------
550 * Local variables:
551 * c-basic-offset: 8
552 * End:
553 */
554