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
22
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/delay.h>
26 #include <linux/init.h>
27 #include <linux/uaccess.h>
28 #include <linux/ioport.h>
29 #include <linux/errno.h>
30 #include <linux/usb.h>
31 #include <linux/i2c.h>
32 #include "usbvision.h"
33
34 #define DBG_I2C (1 << 0)
35
36 static int i2c_debug;
37
38 module_param(i2c_debug, int, 0644); /* debug_i2c_usb mode of the device driver */
39 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
40
41 #define PDEBUG(level, fmt, args...) { \
42 if (i2c_debug & (level)) \
43 printk(KERN_INFO KBUILD_MODNAME ":[%s:%d] " fmt, \
44 __func__, __LINE__ , ## args); \
45 }
46
47 static int usbvision_i2c_write(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
48 short len);
49 static int usbvision_i2c_read(struct usb_usbvision *usbvision, unsigned char addr, char *buf,
50 short len);
51
try_write_address(struct i2c_adapter * i2c_adap,unsigned char addr,int retries)52 static inline int try_write_address(struct i2c_adapter *i2c_adap,
53 unsigned char addr, int retries)
54 {
55 struct usb_usbvision *usbvision;
56 int i, ret = -1;
57 char buf[4];
58
59 usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
60 buf[0] = 0x00;
61 for (i = 0; i <= retries; i++) {
62 ret = (usbvision_i2c_write(usbvision, addr, buf, 1));
63 if (ret == 1)
64 break; /* success! */
65 udelay(5);
66 if (i == retries) /* no success */
67 break;
68 udelay(10);
69 }
70 if (i) {
71 PDEBUG(DBG_I2C, "Needed %d retries for address %#2x", i, addr);
72 PDEBUG(DBG_I2C, "Maybe there's no device at this address");
73 }
74 return ret;
75 }
76
try_read_address(struct i2c_adapter * i2c_adap,unsigned char addr,int retries)77 static inline int try_read_address(struct i2c_adapter *i2c_adap,
78 unsigned char addr, int retries)
79 {
80 struct usb_usbvision *usbvision;
81 int i, ret = -1;
82 char buf[4];
83
84 usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
85 for (i = 0; i <= retries; i++) {
86 ret = (usbvision_i2c_read(usbvision, addr, buf, 1));
87 if (ret == 1)
88 break; /* success! */
89 udelay(5);
90 if (i == retries) /* no success */
91 break;
92 udelay(10);
93 }
94 if (i) {
95 PDEBUG(DBG_I2C, "Needed %d retries for address %#2x", i, addr);
96 PDEBUG(DBG_I2C, "Maybe there's no device at this address");
97 }
98 return ret;
99 }
100
usb_find_address(struct i2c_adapter * i2c_adap,struct i2c_msg * msg,int retries,unsigned char * add)101 static inline int usb_find_address(struct i2c_adapter *i2c_adap,
102 struct i2c_msg *msg, int retries,
103 unsigned char *add)
104 {
105 unsigned short flags = msg->flags;
106
107 unsigned char addr;
108 int ret;
109
110 addr = (msg->addr << 1);
111 if (flags & I2C_M_RD)
112 addr |= 1;
113
114 add[0] = addr;
115 if (flags & I2C_M_RD)
116 ret = try_read_address(i2c_adap, addr, retries);
117 else
118 ret = try_write_address(i2c_adap, addr, retries);
119
120 if (ret != 1)
121 return -EREMOTEIO;
122
123 return 0;
124 }
125
126 static int
usbvision_i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg msgs[],int num)127 usbvision_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
128 {
129 struct i2c_msg *pmsg;
130 struct usb_usbvision *usbvision;
131 int i, ret;
132 unsigned char addr = 0;
133
134 usbvision = (struct usb_usbvision *)i2c_get_adapdata(i2c_adap);
135
136 for (i = 0; i < num; i++) {
137 pmsg = &msgs[i];
138 ret = usb_find_address(i2c_adap, pmsg, i2c_adap->retries, &addr);
139 if (ret != 0) {
140 PDEBUG(DBG_I2C, "got NAK from device, message #%d", i);
141 return (ret < 0) ? ret : -EREMOTEIO;
142 }
143
144 if (pmsg->flags & I2C_M_RD) {
145 /* read bytes into buffer */
146 ret = (usbvision_i2c_read(usbvision, addr, pmsg->buf, pmsg->len));
147 if (ret < pmsg->len)
148 return (ret < 0) ? ret : -EREMOTEIO;
149 } else {
150 /* write bytes from buffer */
151 ret = (usbvision_i2c_write(usbvision, addr, pmsg->buf, pmsg->len));
152 if (ret < pmsg->len)
153 return (ret < 0) ? ret : -EREMOTEIO;
154 }
155 }
156 return num;
157 }
158
functionality(struct i2c_adapter * adap)159 static u32 functionality(struct i2c_adapter *adap)
160 {
161 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
162 }
163
164 /* -----exported algorithm data: ------------------------------------- */
165
166 static const struct i2c_algorithm usbvision_algo = {
167 .master_xfer = usbvision_i2c_xfer,
168 .smbus_xfer = NULL,
169 .functionality = functionality,
170 };
171
172
173 /* ----------------------------------------------------------------------- */
174 /* usbvision specific I2C functions */
175 /* ----------------------------------------------------------------------- */
176 static const struct i2c_adapter i2c_adap_template;
177
usbvision_i2c_register(struct usb_usbvision * usbvision)178 int usbvision_i2c_register(struct usb_usbvision *usbvision)
179 {
180 static unsigned short saa711x_addrs[] = {
181 0x4a >> 1, 0x48 >> 1, /* SAA7111, SAA7111A and SAA7113 */
182 0x42 >> 1, 0x40 >> 1, /* SAA7114, SAA7115 and SAA7118 */
183 I2C_CLIENT_END };
184
185 if (usbvision->registered_i2c)
186 return 0;
187
188 usbvision->i2c_adap = i2c_adap_template;
189
190 snprintf(usbvision->i2c_adap.name, sizeof(usbvision->i2c_adap.name),
191 "usbvision-%d-%s",
192 usbvision->dev->bus->busnum, usbvision->dev->devpath);
193 PDEBUG(DBG_I2C, "Adaptername: %s", usbvision->i2c_adap.name);
194 usbvision->i2c_adap.dev.parent = &usbvision->dev->dev;
195
196 i2c_set_adapdata(&usbvision->i2c_adap, &usbvision->v4l2_dev);
197
198 if (usbvision_write_reg(usbvision, USBVISION_SER_MODE, USBVISION_IIC_LRNACK) < 0) {
199 printk(KERN_ERR "usbvision_i2c_register: can't write reg\n");
200 return -EBUSY;
201 }
202
203 PDEBUG(DBG_I2C, "I2C debugging is enabled [i2c]");
204 PDEBUG(DBG_I2C, "ALGO debugging is enabled [i2c]");
205
206 /* register new adapter to i2c module... */
207
208 usbvision->i2c_adap.algo = &usbvision_algo;
209
210 usbvision->i2c_adap.timeout = 100; /* default values, should */
211 usbvision->i2c_adap.retries = 3; /* be replaced by defines */
212
213 i2c_add_adapter(&usbvision->i2c_adap);
214
215 PDEBUG(DBG_I2C, "i2c bus for %s registered", usbvision->i2c_adap.name);
216
217 /* Request the load of the i2c modules we need */
218 switch (usbvision_device_data[usbvision->dev_model].codec) {
219 case CODEC_SAA7113:
220 case CODEC_SAA7111:
221 /* Without this delay the detection of the saa711x is
222 hit-and-miss. */
223 mdelay(10);
224 v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
225 &usbvision->i2c_adap,
226 "saa7115_auto", 0, saa711x_addrs);
227 break;
228 }
229 if (usbvision_device_data[usbvision->dev_model].tuner == 1) {
230 struct v4l2_subdev *sd;
231 enum v4l2_i2c_tuner_type type;
232 struct tuner_setup tun_setup;
233
234 sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
235 &usbvision->i2c_adap,
236 "tuner", 0, v4l2_i2c_tuner_addrs(ADDRS_DEMOD));
237 /* depending on whether we found a demod or not, select
238 the tuner type. */
239 type = sd ? ADDRS_TV_WITH_DEMOD : ADDRS_TV;
240
241 sd = v4l2_i2c_new_subdev(&usbvision->v4l2_dev,
242 &usbvision->i2c_adap,
243 "tuner", 0, v4l2_i2c_tuner_addrs(type));
244
245 if (sd == NULL)
246 return -ENODEV;
247 if (usbvision->tuner_type != -1) {
248 tun_setup.mode_mask = T_ANALOG_TV | T_RADIO;
249 tun_setup.type = usbvision->tuner_type;
250 tun_setup.addr = v4l2_i2c_subdev_addr(sd);
251 call_all(usbvision, tuner, s_type_addr, &tun_setup);
252 }
253 }
254 usbvision->registered_i2c = 1;
255
256 return 0;
257 }
258
usbvision_i2c_unregister(struct usb_usbvision * usbvision)259 int usbvision_i2c_unregister(struct usb_usbvision *usbvision)
260 {
261 if (!usbvision->registered_i2c)
262 return 0;
263
264 i2c_del_adapter(&(usbvision->i2c_adap));
265 usbvision->registered_i2c = 0;
266
267 PDEBUG(DBG_I2C, "i2c bus for %s unregistered", usbvision->i2c_adap.name);
268
269 return 0;
270 }
271
272 static int
usbvision_i2c_read_max4(struct usb_usbvision * usbvision,unsigned char addr,char * buf,short len)273 usbvision_i2c_read_max4(struct usb_usbvision *usbvision, unsigned char addr,
274 char *buf, short len)
275 {
276 int rc, retries;
277
278 for (retries = 5;;) {
279 rc = usbvision_write_reg(usbvision, USBVISION_SER_ADRS, addr);
280 if (rc < 0)
281 return rc;
282
283 /* Initiate byte read cycle */
284 /* USBVISION_SER_CONT <- d0-d2 n. of bytes to r/w */
285 /* d3 0=Wr 1=Rd */
286 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT,
287 (len & 0x07) | 0x18);
288 if (rc < 0)
289 return rc;
290
291 /* Test for Busy and ACK */
292 do {
293 /* USBVISION_SER_CONT -> d4 == 0 busy */
294 rc = usbvision_read_reg(usbvision, USBVISION_SER_CONT);
295 } while (rc > 0 && ((rc & 0x10) != 0)); /* Retry while busy */
296 if (rc < 0)
297 return rc;
298
299 /* USBVISION_SER_CONT -> d5 == 1 Not ack */
300 if ((rc & 0x20) == 0) /* Ack? */
301 break;
302
303 /* I2C abort */
304 rc = usbvision_write_reg(usbvision, USBVISION_SER_CONT, 0x00);
305 if (rc < 0)
306 return rc;
307
308 if (--retries < 0)
309 return -1;
310 }
311
312 switch (len) {
313 case 4:
314 buf[3] = usbvision_read_reg(usbvision, USBVISION_SER_DAT4);
315 /* fall through */
316 case 3:
317 buf[2] = usbvision_read_reg(usbvision, USBVISION_SER_DAT3);
318 /* fall through */
319 case 2:
320 buf[1] = usbvision_read_reg(usbvision, USBVISION_SER_DAT2);
321 /* fall through */
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 = usbvision->ctrl_urb_buffer;
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 const struct i2c_adapter i2c_adap_template = {
445 .owner = THIS_MODULE,
446 .name = "usbvision",
447 };
448