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
114 addr = (msg->addr << 1);
115 if (flags & I2C_M_RD)
116 addr |= 1;
117
118 add[0] = addr;
119 if (flags & I2C_M_RD)
120 ret = try_read_address(i2c_adap, addr, retries);
121 else
122 ret = try_write_address(i2c_adap, addr, retries);
123
124 if (ret != 1)
125 return -EREMOTEIO;
126
127 return 0;
128 }
129
130 static int
usbvision_i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg msgs[],int num)131 usbvision_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
132 {
133 struct i2c_msg *pmsg;
134 struct usb_usbvision *usbvision;
135 int i, ret;
136 unsigned char addr = 0;
137
138 usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
139
140 for (i = 0; i < num; i++) {
141 pmsg = &msgs[i];
142 ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
143 if (ret != 0) {
144 PDEBUG(DBG_I2C, "got NAK from device, message #%d", i);
145 return (ret < 0) ? ret : -EREMOTEIO;
146 }
147
148 if (pmsg->flags & I2C_M_RD) {
149 /* read bytes into buffer */
150 ret = (usbvision_i2c_read(usbvision, addr, pmsg->buf, pmsg->len));
151 if (ret < pmsg->len)
152 return (ret < 0) ? ret : -EREMOTEIO;
153 } else {
154 /* write bytes from buffer */
155 ret = (usbvision_i2c_write(usbvision, addr, pmsg->buf, pmsg->len));
156 if (ret < pmsg->len)
157 return (ret < 0) ? ret : -EREMOTEIO;
158 }
159 }
160 return num;
161 }
162
functionality(struct i2c_adapter * adap)163 static u32 functionality(struct i2c_adapter *adap)
164 {
165 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
166 }
167
168 /* -----exported algorithm data: ------------------------------------- */
169
170 static struct i2c_algorithm usbvision_algo = {
171 .master_xfer = usbvision_i2c_xfer,
172 .smbus_xfer = NULL,
173 .functionality = functionality,
174 };
175
176
177 /* ----------------------------------------------------------------------- */
178 /* usbvision specific I2C functions */
179 /* ----------------------------------------------------------------------- */
180 static struct i2c_adapter i2c_adap_template;
181
usbvision_i2c_register(struct usb_usbvision * usbvision)182 int usbvision_i2c_register(struct usb_usbvision *usbvision)
183 {
184 static unsigned short saa711x_addrs[] = {
185 0x4a >> 1, 0x48 >> 1, /* SAA7111, SAA7111A and SAA7113 */
186 0x42 >> 1, 0x40 >> 1, /* SAA7114, SAA7115 and SAA7118 */
187 I2C_CLIENT_END };
188
189 if (usbvision->registered_i2c)
190 return 0;
191
192 memcpy(&usbvision->i2c_adap, &i2c_adap_template,
193 sizeof(struct i2c_adapter));
194
195 sprintf(usbvision->i2c_adap.name, "%s-%d-%s", i2c_adap_template.name,
196 usbvision->dev->bus->busnum, usbvision->dev->devpath);
197 PDEBUG(DBG_I2C, "Adaptername: %s", usbvision->i2c_adap.name);
198 usbvision->i2c_adap.dev.parent = &usbvision->dev->dev;
199
200 i2c_set_adapdata(&usbvision->i2c_adap, &usbvision->v4l2_dev);
201
202 if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
203 printk(KERN_ERR "usbvision_i2c_register: can't write reg\n");
204 return -EBUSY;
205 }
206
207 PDEBUG(DBG_I2C, "I2C debugging is enabled [i2c]");
208 PDEBUG(DBG_I2C, "ALGO debugging is enabled [i2c]");
209
210 /* register new adapter to i2c module... */
211
212 usbvision->i2c_adap.algo = &usbvision_algo;
213
214 usbvision->i2c_adap.timeout = 100; /* default values, should */
215 usbvision->i2c_adap.retries = 3; /* be replaced by defines */
216
217 i2c_add_adapter(&usbvision->i2c_adap);
218
219 PDEBUG(DBG_I2C, "i2c bus for %s registered", usbvision->i2c_adap.name);
220
221 /* Request the load of the i2c modules we need */
222 switch (usbvision_device_data[usbvision->dev_model].codec) {
223 case CODEC_SAA7113:
224 case CODEC_SAA7111:
225 /* Without this delay the detection of the saa711x is
226 hit-and-miss. */
227 mdelay(10);
228 v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
229 &usbvision->i2c_adap,
230 "saa7115_auto", 0, saa711x_addrs);
231 break;
232 }
233 if (usbvision_device_data[usbvision->dev_model].tuner == 1) {
234 struct v4l2_subdev *sd;
235 enum v4l2_i2c_tuner_type type;
236 struct tuner_setup tun_setup;
237
238 sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
239 &usbvision->i2c_adap,
240 "tuner", 0, v4l2_i2c_tuner_addrs(ADDRS_DEMOD));
241 /* depending on whether we found a demod or not, select
242 the tuner type. */
243 type = sd ? ADDRS_TV_WITH_DEMOD : ADDRS_TV;
244
245 sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
246 &usbvision->i2c_adap,
247 "tuner", 0, v4l2_i2c_tuner_addrs(type));
248
249 if (sd == NULL)
250 return -ENODEV;
251 if (usbvision->tuner_type != -1) {
252 tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
253 tun_setup.type = usbvision->tuner_type;
254 tun_setup.addr = v4l2_i2c_subdev_addr(sd);
255 call_all(usbvision, tuner, s_type_addr, &tun_setup);
256 }
257 }
258 usbvision->registered_i2c = 1;
259
260 return 0;
261 }
262
usbvision_i2c_unregister(struct usb_usbvision * usbvision)263 int usbvision_i2c_unregister(struct usb_usbvision *usbvision)
264 {
265 if (!usbvision->registered_i2c)
266 return 0;
267
268 i2c_del_adapter(&(usbvision->i2c_adap));
269 usbvision->registered_i2c = 0;
270
271 PDEBUG(DBG_I2C, "i2c bus for %s unregistered", usbvision->i2c_adap.name);
272
273 return 0;
274 }
275
276 static int
usbvision_i2c_read_max4(struct usb_usbvision * usbvision,unsigned char addr,char * buf,short len)277 usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
278 char *buf, short len)
279 {
280 int rc, retries;
281
282 for (retries = 5;;) {
283 rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
284 if (rc < 0)
285 return rc;
286
287 /* Initiate byte read cycle */
288 /* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
289 /* d3 0=Wr 1=Rd */
290 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
291 (len & 0x07) | 0x18);
292 if (rc < 0)
293 return rc;
294
295 /* Test for Busy and ACK */
296 do {
297 /* USBVISION_SER_CONT -> d4 == 0 busy */
298 rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
299 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
300 if (rc < 0)
301 return rc;
302
303 /* USBVISION_SER_CONT -> d5 == 1 Not ack */
304 if ((rc & 0x20) == 0) /* Ack? */
305 break;
306
307 /* I2C abort */
308 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
309 if (rc < 0)
310 return rc;
311
312 if (--retries < 0)
313 return -1;
314 }
315
316 switch (len) {
317 case 4:
318 buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
319 case 3:
320 buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
321 case 2:
322 buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
323 case 1:
324 buf[0] = usbvision_read_reg(usbvision, USBVISION_SER_DAT1);
325 break;
326 default:
327 printk(KERN_ERR
328 "usbvision_i2c_read_max4: buffer length > 4\n");
329 }
330
331 if (i2c_debug & DBG_I2C) {
332 int idx;
333
334 for (idx = 0; idx < len; idx++)
335 PDEBUG(DBG_I2C, "read %x from address %x", (unsigned char)buf[idx], addr);
336 }
337 return len;
338 }
339
340
usbvision_i2c_write_max4(struct usb_usbvision * usbvision,unsigned char addr,const char * buf,short len)341 static int usbvision_i2c_write_max4(struct usb_usbvision *usbvision,
342 unsigned char addr, const char *buf,
343 short len)
344 {
345 int rc, retries;
346 int i;
347 unsigned char value[6];
348 unsigned char ser_cont;
349
350 ser_cont = (len & 0x07) | 0x10;
351
352 value[0] = addr;
353 value[1] = ser_cont;
354 for (i = 0; i < len; i++)
355 value[i + 2] = buf[i];
356
357 for (retries = 5;;) {
358 rc = usb_control_msg(usbvision->dev,
359 usb_sndctrlpipe(usbvision->dev, 1),
360 USBVISION_OP_CODE,
361 USB_DIR_OUT | USB_TYPE_VENDOR |
362 USB_RECIP_ENDPOINT, 0,
363 (__u16) USBVISION_SER_ADRS, value,
364 len + 2, HZ);
365
366 if (rc < 0)
367 return rc;
368
369 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
370 (len & 0x07) | 0x10);
371 if (rc < 0)
372 return rc;
373
374 /* Test for Busy and ACK */
375 do {
376 rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
377 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
378 if (rc < 0)
379 return rc;
380
381 if ((rc & 0x20) == 0) /* Ack? */
382 break;
383
384 /* I2C abort */
385 usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
386
387 if (--retries < 0)
388 return -1;
389
390 }
391
392 if (i2c_debug & DBG_I2C) {
393 int idx;
394
395 for (idx = 0; idx < len; idx++)
396 PDEBUG(DBG_I2C, "wrote %x at address %x", (unsigned char)buf[idx], addr);
397 }
398 return len;
399 }
400
usbvision_i2c_write(struct usb_usbvision * usbvision,unsigned char addr,char * buf,short len)401 static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
402 short len)
403 {
404 char *buf_ptr = buf;
405 int retval;
406 int wrcount = 0;
407 int count;
408 int max_len = 4;
409
410 while (len > 0) {
411 count = (len > max_len) ? max_len : len;
412 retval = usbvision_i2c_write_max4(usbvision, addr, buf_ptr, count);
413 if (retval > 0) {
414 len -= count;
415 buf_ptr += count;
416 wrcount += count;
417 } else
418 return (retval < 0) ? retval : -EFAULT;
419 }
420 return wrcount;
421 }
422
usbvision_i2c_read(struct usb_usbvision * usbvision,unsigned char addr,char * buf,short len)423 static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
424 short len)
425 {
426 char temp[4];
427 int retval, i;
428 int rdcount = 0;
429 int count;
430
431 while (len > 0) {
432 count = (len > 3) ? 4 : len;
433 retval = usbvision_i2c_read_max4(usbvision, addr, temp, count);
434 if (retval > 0) {
435 for (i = 0; i < len; i++)
436 buf[rdcount + i] = temp[i];
437 len -= count;
438 rdcount += count;
439 } else
440 return (retval < 0) ? retval : -EFAULT;
441 }
442 return rdcount;
443 }
444
445 static struct i2c_adapter i2c_adap_template = {
446 .owner = THIS_MODULE,
447 .name = "usbvision",
448 };
449
450 /*
451 * Overrides for Emacs so that we follow Linus's tabbing style.
452 * ---------------------------------------------------------------------------
453 * Local variables:
454 * c-basic-offset: 8
455 * End:
456 */
457