1 /*
2 * usbvision_i2c.c
3 * i2c algorithm for USB-I2C Bridges
4 *
5 * Copyright (c) 1999-2007 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/init.h>
31 #include <linux/uaccess.h>
32 #include <linux/ioport.h>
33 #include <linux/errno.h>
34 #include <linux/usb.h>
35 #include <linux/i2c.h>
36 #include "usbvision.h"
37
38 #define DBG_I2C (1 << 0)
39
40 static int i2c_debug;
41
42 module_param(i2c_debug, int, 0644); /* debug_i2c_usb mode of the device driver */
43 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
44
45 #define PDEBUG(level, fmt, args...) { \
46 if (i2c_debug & (level)) \
47 printk(KERN_INFO KBUILD_MODNAME ":[%s:%d] " fmt, \
48 __func__, __LINE__ , ## args); \
49 }
50
51 static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
52 short len);
53 static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
54 short len);
55
try_write_address(struct i2c_adapter * i2c_adap,unsigned char addr,int retries)56 static inline int try_write_address(struct i2c_adapter *i2c_adap,
57 unsigned char addr, int retries)
58 {
59 struct usb_usbvision *usbvision;
60 int i, ret = -1;
61 char buf[4];
62
63 usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
64 buf[0] = 0x00;
65 for (i = 0; i <= retries; i++) {
66 ret = (usbvision_i2c_write(usbvision, addr, buf, 1));
67 if (ret == 1)
68 break; /* success! */
69 udelay(5);
70 if (i == retries) /* no success */
71 break;
72 udelay(10);
73 }
74 if (i) {
75 PDEBUG(DBG_I2C, "Needed %d retries for address %#2x", i, addr);
76 PDEBUG(DBG_I2C, "Maybe there's no device at this address");
77 }
78 return ret;
79 }
80
try_read_address(struct i2c_adapter * i2c_adap,unsigned char addr,int retries)81 static inline int try_read_address(struct i2c_adapter *i2c_adap,
82 unsigned char addr, int retries)
83 {
84 struct usb_usbvision *usbvision;
85 int i, ret = -1;
86 char buf[4];
87
88 usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
89 for (i = 0; i <= retries; i++) {
90 ret = (usbvision_i2c_read(usbvision, addr, buf, 1));
91 if (ret == 1)
92 break; /* success! */
93 udelay(5);
94 if (i == retries) /* no success */
95 break;
96 udelay(10);
97 }
98 if (i) {
99 PDEBUG(DBG_I2C, "Needed %d retries for address %#2x", i, addr);
100 PDEBUG(DBG_I2C, "Maybe there's no device at this address");
101 }
102 return ret;
103 }
104
usb_find_address(struct i2c_adapter * i2c_adap,struct i2c_msg * msg,int retries,unsigned char * add)105 static inline int usb_find_address(struct i2c_adapter *i2c_adap,
106 struct i2c_msg *msg, int retries,
107 unsigned char *add)
108 {
109 unsigned short flags = msg->flags;
110
111 unsigned char addr;
112 int ret;
113 if ((flags & I2C_M_TEN)) {
114 /* a ten bit address */
115 addr = 0xf0 | ((msg->addr >> 7) & 0x03);
116 /* try extended address code... */
117 ret = try_write_address(i2c_adap, addr, retries);
118 if (ret != 1) {
119 dev_err(&i2c_adap->dev,
120 "died at extended address code, while writing\n");
121 return -EREMOTEIO;
122 }
123 add[0] = addr;
124 if (flags & I2C_M_RD) {
125 /* okay, now switch into reading mode */
126 addr |= 0x01;
127 ret = try_read_address(i2c_adap, addr, retries);
128 if (ret != 1) {
129 dev_err(&i2c_adap->dev,
130 "died at extended address code, while reading\n");
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
140 add[0] = addr;
141 if (flags & I2C_M_RD)
142 ret = try_read_address(i2c_adap, addr, retries);
143 else
144 ret = try_write_address(i2c_adap, addr, retries);
145
146 if (ret != 1)
147 return -EREMOTEIO;
148 }
149 return 0;
150 }
151
152 static int
usbvision_i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg msgs[],int num)153 usbvision_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
154 {
155 struct i2c_msg *pmsg;
156 struct usb_usbvision *usbvision;
157 int i, ret;
158 unsigned char addr = 0;
159
160 usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
161
162 for (i = 0; i < num; i++) {
163 pmsg = &msgs[i];
164 ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
165 if (ret != 0) {
166 PDEBUG(DBG_I2C, "got NAK from device, message #%d", i);
167 return (ret < 0) ? ret : -EREMOTEIO;
168 }
169
170 if (pmsg->flags & I2C_M_RD) {
171 /* read bytes into buffer */
172 ret = (usbvision_i2c_read(usbvision, addr, pmsg->buf, pmsg->len));
173 if (ret < pmsg->len)
174 return (ret < 0) ? ret : -EREMOTEIO;
175 } else {
176 /* write bytes from buffer */
177 ret = (usbvision_i2c_write(usbvision, addr, pmsg->buf, pmsg->len));
178 if (ret < pmsg->len)
179 return (ret < 0) ? ret : -EREMOTEIO;
180 }
181 }
182 return num;
183 }
184
functionality(struct i2c_adapter * adap)185 static u32 functionality(struct i2c_adapter *adap)
186 {
187 return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
188 }
189
190 /* -----exported algorithm data: ------------------------------------- */
191
192 static struct i2c_algorithm usbvision_algo = {
193 .master_xfer = usbvision_i2c_xfer,
194 .smbus_xfer = NULL,
195 .functionality = functionality,
196 };
197
198
199 /* ----------------------------------------------------------------------- */
200 /* usbvision specific I2C functions */
201 /* ----------------------------------------------------------------------- */
202 static struct i2c_adapter i2c_adap_template;
203
usbvision_i2c_register(struct usb_usbvision * usbvision)204 int usbvision_i2c_register(struct usb_usbvision *usbvision)
205 {
206 static unsigned short saa711x_addrs[] = {
207 0x4a >> 1, 0x48 >> 1, /* SAA7111, SAA7111A and SAA7113 */
208 0x42 >> 1, 0x40 >> 1, /* SAA7114, SAA7115 and SAA7118 */
209 I2C_CLIENT_END };
210
211 if (usbvision->registered_i2c)
212 return 0;
213
214 memcpy(&usbvision->i2c_adap, &i2c_adap_template,
215 sizeof(struct i2c_adapter));
216
217 sprintf(usbvision->i2c_adap.name, "%s-%d-%s", i2c_adap_template.name,
218 usbvision->dev->bus->busnum, usbvision->dev->devpath);
219 PDEBUG(DBG_I2C, "Adaptername: %s", usbvision->i2c_adap.name);
220 usbvision->i2c_adap.dev.parent = &usbvision->dev->dev;
221
222 i2c_set_adapdata(&usbvision->i2c_adap, &usbvision->v4l2_dev);
223
224 if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
225 printk(KERN_ERR "usbvision_register: can't write reg\n");
226 return -EBUSY;
227 }
228
229 PDEBUG(DBG_I2C, "I2C debugging is enabled [i2c]");
230 PDEBUG(DBG_I2C, "ALGO debugging is enabled [i2c]");
231
232 /* register new adapter to i2c module... */
233
234 usbvision->i2c_adap.algo = &usbvision_algo;
235
236 usbvision->i2c_adap.timeout = 100; /* default values, should */
237 usbvision->i2c_adap.retries = 3; /* be replaced by defines */
238
239 i2c_add_adapter(&usbvision->i2c_adap);
240
241 PDEBUG(DBG_I2C, "i2c bus for %s registered", usbvision->i2c_adap.name);
242
243 /* Request the load of the i2c modules we need */
244 switch (usbvision_device_data[usbvision->dev_model].codec) {
245 case CODEC_SAA7113:
246 case CODEC_SAA7111:
247 /* Without this delay the detection of the saa711x is
248 hit-and-miss. */
249 mdelay(10);
250 v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
251 &usbvision->i2c_adap,
252 "saa7115_auto", 0, saa711x_addrs);
253 break;
254 }
255 if (usbvision_device_data[usbvision->dev_model].tuner == 1) {
256 struct v4l2_subdev *sd;
257 enum v4l2_i2c_tuner_type type;
258 struct tuner_setup tun_setup;
259
260 sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
261 &usbvision->i2c_adap,
262 "tuner", 0, v4l2_i2c_tuner_addrs(ADDRS_DEMOD));
263 /* depending on whether we found a demod or not, select
264 the tuner type. */
265 type = sd ? ADDRS_TV_WITH_DEMOD : ADDRS_TV;
266
267 sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
268 &usbvision->i2c_adap,
269 "tuner", 0, v4l2_i2c_tuner_addrs(type));
270
271 if (sd == NULL)
272 return -ENODEV;
273 if (usbvision->tuner_type != -1) {
274 tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
275 tun_setup.type = usbvision->tuner_type;
276 tun_setup.addr = v4l2_i2c_subdev_addr(sd);
277 call_all(usbvision, tuner, s_type_addr, &tun_setup);
278 }
279 }
280 usbvision->registered_i2c = 1;
281
282 return 0;
283 }
284
usbvision_i2c_unregister(struct usb_usbvision * usbvision)285 int usbvision_i2c_unregister(struct usb_usbvision *usbvision)
286 {
287 if (!usbvision->registered_i2c)
288 return 0;
289
290 i2c_del_adapter(&(usbvision->i2c_adap));
291 usbvision->registered_i2c = 0;
292
293 PDEBUG(DBG_I2C, "i2c bus for %s unregistered", usbvision->i2c_adap.name);
294
295 return 0;
296 }
297
298 static int
usbvision_i2c_read_max4(struct usb_usbvision * usbvision,unsigned char addr,char * buf,short len)299 usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
300 char *buf, short len)
301 {
302 int rc, retries;
303
304 for (retries = 5;;) {
305 rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
306 if (rc < 0)
307 return rc;
308
309 /* Initiate byte read cycle */
310 /* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
311 /* d3 0=Wr 1=Rd */
312 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
313 (len & 0x07) | 0x18);
314 if (rc < 0)
315 return rc;
316
317 /* Test for Busy and ACK */
318 do {
319 /* USBVISION_SER_CONT -> d4 == 0 busy */
320 rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
321 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
322 if (rc < 0)
323 return rc;
324
325 /* USBVISION_SER_CONT -> d5 == 1 Not ack */
326 if ((rc & 0x20) == 0) /* Ack? */
327 break;
328
329 /* I2C abort */
330 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
331 if (rc < 0)
332 return rc;
333
334 if (--retries < 0)
335 return -1;
336 }
337
338 switch (len) {
339 case 4:
340 buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
341 case 3:
342 buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
343 case 2:
344 buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
345 case 1:
346 buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
347 break;
348 default:
349 printk(KERN_ERR
350 "usbvision_i2c_read_max4: buffer length > 4\n");
351 }
352
353 if (i2c_debug & DBG_I2C) {
354 int idx;
355
356 for (idx = 0; idx < len; idx++)
357 PDEBUG(DBG_I2C, "read %x from address %x", (unsigned char)buf[idx], addr);
358 }
359 return len;
360 }
361
362
usbvision_i2c_write_max4(struct usb_usbvision * usbvision,unsigned char addr,const char * buf,short len)363 static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
364 unsigned char addr, const char *buf,
365 short len)
366 {
367 int rc, retries;
368 int i;
369 unsigned char value[6];
370 unsigned char ser_cont;
371
372 ser_cont = (len & 0x07) | 0x10;
373
374 value[0] = addr;
375 value[1] = ser_cont;
376 for (i = 0; i < len; i++)
377 value[i + 2] = buf[i];
378
379 for (retries = 5;;) {
380 rc = usb_control_msg(usbvision->dev,
381 usb_sndctrlpipe(usbvision->dev, 1),
382 USBVISION_OP_CODE,
383 USB_DIR_OUT | USB_TYPE_VENDOR |
384 USB_RECIP_ENDPOINT, 0,
385 (__u16) USBVISION_SER_ADRS, value,
386 len + 2, HZ);
387
388 if (rc < 0)
389 return rc;
390
391 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
392 (len & 0x07) | 0x10);
393 if (rc < 0)
394 return rc;
395
396 /* Test for Busy and ACK */
397 do {
398 rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
399 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
400 if (rc < 0)
401 return rc;
402
403 if ((rc & 0x20) == 0) /* Ack? */
404 break;
405
406 /* I2C abort */
407 usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
408
409 if (--retries < 0)
410 return -1;
411
412 }
413
414 if (i2c_debug & DBG_I2C) {
415 int idx;
416
417 for (idx = 0; idx < len; idx++)
418 PDEBUG(DBG_I2C, "wrote %x at address %x", (unsigned char)buf[idx], addr);
419 }
420 return len;
421 }
422
usbvision_i2c_write(struct usb_usbvision * usbvision,unsigned char addr,char * buf,short len)423 static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
424 short len)
425 {
426 char *buf_ptr = buf;
427 int retval;
428 int wrcount = 0;
429 int count;
430 int max_len = 4;
431
432 while (len > 0) {
433 count = (len > max_len) ? max_len : len;
434 retval = usbvision_i2c_write_max4(usbvision, addr, buf_ptr, count);
435 if (retval > 0) {
436 len -= count;
437 buf_ptr += count;
438 wrcount += count;
439 } else
440 return (retval < 0) ? retval : -EFAULT;
441 }
442 return wrcount;
443 }
444
usbvision_i2c_read(struct usb_usbvision * usbvision,unsigned char addr,char * buf,short len)445 static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
446 short len)
447 {
448 char temp[4];
449 int retval, i;
450 int rdcount = 0;
451 int count;
452
453 while (len > 0) {
454 count = (len > 3) ? 4 : len;
455 retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
456 if (retval > 0) {
457 for (i = 0; i < len; i++)
458 buf[rdcount + i] = temp[i];
459 len -= count;
460 rdcount += count;
461 } else
462 return (retval < 0) ? retval : -EFAULT;
463 }
464 return rdcount;
465 }
466
467 static struct i2c_adapter i2c_adap_template = {
468 .owner = THIS_MODULE,
469 .name = "usbvision",
470 };
471
472 /*
473 * Overrides for Emacs so that we follow Linus's tabbing style.
474 * ---------------------------------------------------------------------------
475 * Local variables:
476 * c-basic-offset: 8
477 * End:
478 */
479