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