1 /*
2    cx231xx-i2c.c - driver for Conexant Cx23100/101/102 USB video capture devices
3 
4    Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
5 		Based on em28xx driver
6 		Based on Cx23885 driver
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 2 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program; if not, write to the Free Software
20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 
23 #include <linux/module.h>
24 #include <linux/kernel.h>
25 #include <linux/usb.h>
26 #include <linux/i2c.h>
27 #include <media/v4l2-common.h>
28 #include <media/tuner.h>
29 
30 #include "cx231xx.h"
31 
32 /* ----------------------------------------------------------- */
33 
34 static unsigned int i2c_scan;
35 module_param(i2c_scan, int, 0444);
36 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
37 
38 static unsigned int i2c_debug;
39 module_param(i2c_debug, int, 0644);
40 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
41 
42 #define dprintk1(lvl, fmt, args...)			\
43 do {							\
44 	if (i2c_debug >= lvl) {				\
45 		printk(fmt, ##args);			\
46 		}					\
47 } while (0)
48 
49 #define dprintk2(lvl, fmt, args...)			\
50 do {							\
51 	if (i2c_debug >= lvl) {				\
52 		printk(KERN_DEBUG "%s at %s: " fmt,	\
53 		       dev->name, __func__ , ##args);	\
54       } 						\
55 } while (0)
56 
57 static inline bool is_tuner(struct cx231xx *dev, struct cx231xx_i2c *bus,
58 			const struct i2c_msg *msg, int tuner_type)
59 {
60 	if (bus->nr != dev->board.tuner_i2c_master)
61 		return false;
62 
63 	if (msg->addr != dev->board.tuner_addr)
64 		return false;
65 
66 	if (dev->tuner_type != tuner_type)
67 		return false;
68 
69 	return true;
70 }
71 
72 /*
73  * cx231xx_i2c_send_bytes()
74  */
75 int cx231xx_i2c_send_bytes(struct i2c_adapter *i2c_adap,
76 			   const struct i2c_msg *msg)
77 {
78 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
79 	struct cx231xx *dev = bus->dev;
80 	struct cx231xx_i2c_xfer_data req_data;
81 	int status = 0;
82 	u16 size = 0;
83 	u8 loop = 0;
84 	u8 saddr_len = 1;
85 	u8 *buf_ptr = NULL;
86 	u16 saddr = 0;
87 	u8 need_gpio = 0;
88 
89 	if (is_tuner(dev, bus, msg, TUNER_XC5000)) {
90 		size = msg->len;
91 
92 		if (size == 2) {	/* register write sub addr */
93 			/* Just writing sub address will cause problem
94 			* to XC5000. So ignore the request */
95 			return 0;
96 		} else if (size == 4) {	/* register write with sub addr */
97 			if (msg->len >= 2)
98 				saddr = msg->buf[0] << 8 | msg->buf[1];
99 			else if (msg->len == 1)
100 				saddr = msg->buf[0];
101 
102 			switch (saddr) {
103 			case 0x0000:	/* start tuner calibration mode */
104 				need_gpio = 1;
105 				/* FW Loading is done */
106 				dev->xc_fw_load_done = 1;
107 				break;
108 			case 0x000D:	/* Set signal source */
109 			case 0x0001:	/* Set TV standard - Video */
110 			case 0x0002:	/* Set TV standard - Audio */
111 			case 0x0003:	/* Set RF Frequency */
112 				need_gpio = 1;
113 				break;
114 			default:
115 				if (dev->xc_fw_load_done)
116 					need_gpio = 1;
117 				break;
118 			}
119 
120 			if (need_gpio) {
121 				dprintk1(1,
122 				"GPIO WRITE: addr 0x%x, len %d, saddr 0x%x\n",
123 				msg->addr, msg->len, saddr);
124 
125 				return dev->cx231xx_gpio_i2c_write(dev,
126 								   msg->addr,
127 								   msg->buf,
128 								   msg->len);
129 			}
130 		}
131 
132 		/* special case for Xc5000 tuner case */
133 		saddr_len = 1;
134 
135 		/* adjust the length to correct length */
136 		size -= saddr_len;
137 		buf_ptr = (u8 *) (msg->buf + 1);
138 
139 		do {
140 			/* prepare xfer_data struct */
141 			req_data.dev_addr = msg->addr;
142 			req_data.direction = msg->flags;
143 			req_data.saddr_len = saddr_len;
144 			req_data.saddr_dat = msg->buf[0];
145 			req_data.buf_size = size > 16 ? 16 : size;
146 			req_data.p_buffer = (u8 *) (buf_ptr + loop * 16);
147 
148 			bus->i2c_nostop = (size > 16) ? 1 : 0;
149 			bus->i2c_reserve = (loop == 0) ? 0 : 1;
150 
151 			/* usb send command */
152 			status = dev->cx231xx_send_usb_command(bus, &req_data);
153 			loop++;
154 
155 			if (size >= 16)
156 				size -= 16;
157 			else
158 				size = 0;
159 
160 		} while (size > 0);
161 
162 		bus->i2c_nostop = 0;
163 		bus->i2c_reserve = 0;
164 
165 	} else {		/* regular case */
166 
167 		/* prepare xfer_data struct */
168 		req_data.dev_addr = msg->addr;
169 		req_data.direction = msg->flags;
170 		req_data.saddr_len = 0;
171 		req_data.saddr_dat = 0;
172 		req_data.buf_size = msg->len;
173 		req_data.p_buffer = msg->buf;
174 
175 		/* usb send command */
176 		status = dev->cx231xx_send_usb_command(bus, &req_data);
177 	}
178 
179 	return status < 0 ? status : 0;
180 }
181 
182 /*
183  * cx231xx_i2c_recv_bytes()
184  * read a byte from the i2c device
185  */
186 static int cx231xx_i2c_recv_bytes(struct i2c_adapter *i2c_adap,
187 				  const struct i2c_msg *msg)
188 {
189 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
190 	struct cx231xx *dev = bus->dev;
191 	struct cx231xx_i2c_xfer_data req_data;
192 	int status = 0;
193 	u16 saddr = 0;
194 	u8 need_gpio = 0;
195 
196 	if (is_tuner(dev, bus, msg, TUNER_XC5000)) {
197 		if (msg->len == 2)
198 			saddr = msg->buf[0] << 8 | msg->buf[1];
199 		else if (msg->len == 1)
200 			saddr = msg->buf[0];
201 
202 		if (dev->xc_fw_load_done) {
203 
204 			switch (saddr) {
205 			case 0x0009:	/* BUSY check */
206 				dprintk1(1,
207 				"GPIO R E A D: Special case BUSY check \n");
208 				/*Try read BUSY register, just set it to zero*/
209 				msg->buf[0] = 0;
210 				if (msg->len == 2)
211 					msg->buf[1] = 0;
212 				return 0;
213 			case 0x0004:	/* read Lock status */
214 				need_gpio = 1;
215 				break;
216 
217 			}
218 
219 			if (need_gpio) {
220 				/* this is a special case to handle Xceive tuner
221 				clock stretch issue with gpio based I2C */
222 
223 				dprintk1(1,
224 				"GPIO R E A D: addr 0x%x, len %d, saddr 0x%x\n",
225 				msg->addr, msg->len,
226 				msg->buf[0] << 8 | msg->buf[1]);
227 
228 				status =
229 				    dev->cx231xx_gpio_i2c_write(dev, msg->addr,
230 								msg->buf,
231 								msg->len);
232 				status =
233 				    dev->cx231xx_gpio_i2c_read(dev, msg->addr,
234 							       msg->buf,
235 							       msg->len);
236 				return status;
237 			}
238 		}
239 
240 		/* prepare xfer_data struct */
241 		req_data.dev_addr = msg->addr;
242 		req_data.direction = msg->flags;
243 		req_data.saddr_len = msg->len;
244 		req_data.saddr_dat = msg->buf[0] << 8 | msg->buf[1];
245 		req_data.buf_size = msg->len;
246 		req_data.p_buffer = msg->buf;
247 
248 		/* usb send command */
249 		status = dev->cx231xx_send_usb_command(bus, &req_data);
250 
251 	} else {
252 
253 		/* prepare xfer_data struct */
254 		req_data.dev_addr = msg->addr;
255 		req_data.direction = msg->flags;
256 		req_data.saddr_len = 0;
257 		req_data.saddr_dat = 0;
258 		req_data.buf_size = msg->len;
259 		req_data.p_buffer = msg->buf;
260 
261 		/* usb send command */
262 		status = dev->cx231xx_send_usb_command(bus, &req_data);
263 	}
264 
265 	return status < 0 ? status : 0;
266 }
267 
268 /*
269  * cx231xx_i2c_recv_bytes_with_saddr()
270  * read a byte from the i2c device
271  */
272 static int cx231xx_i2c_recv_bytes_with_saddr(struct i2c_adapter *i2c_adap,
273 					     const struct i2c_msg *msg1,
274 					     const struct i2c_msg *msg2)
275 {
276 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
277 	struct cx231xx *dev = bus->dev;
278 	struct cx231xx_i2c_xfer_data req_data;
279 	int status = 0;
280 	u16 saddr = 0;
281 	u8 need_gpio = 0;
282 
283 	if (msg1->len == 2)
284 		saddr = msg1->buf[0] << 8 | msg1->buf[1];
285 	else if (msg1->len == 1)
286 		saddr = msg1->buf[0];
287 
288 	if (is_tuner(dev, bus, msg2, TUNER_XC5000)) {
289 		if ((msg2->len < 16)) {
290 
291 			dprintk1(1,
292 			"i2c_read: addr 0x%x, len %d, saddr 0x%x, len %d\n",
293 			msg2->addr, msg2->len, saddr, msg1->len);
294 
295 			switch (saddr) {
296 			case 0x0008:	/* read FW load status */
297 				need_gpio = 1;
298 				break;
299 			case 0x0004:	/* read Lock status */
300 				need_gpio = 1;
301 				break;
302 			}
303 
304 			if (need_gpio) {
305 				status =
306 				    dev->cx231xx_gpio_i2c_write(dev, msg1->addr,
307 								msg1->buf,
308 								msg1->len);
309 				status =
310 				    dev->cx231xx_gpio_i2c_read(dev, msg2->addr,
311 							       msg2->buf,
312 							       msg2->len);
313 				return status;
314 			}
315 		}
316 	}
317 
318 	/* prepare xfer_data struct */
319 	req_data.dev_addr = msg2->addr;
320 	req_data.direction = msg2->flags;
321 	req_data.saddr_len = msg1->len;
322 	req_data.saddr_dat = saddr;
323 	req_data.buf_size = msg2->len;
324 	req_data.p_buffer = msg2->buf;
325 
326 	/* usb send command */
327 	status = dev->cx231xx_send_usb_command(bus, &req_data);
328 
329 	return status < 0 ? status : 0;
330 }
331 
332 /*
333  * cx231xx_i2c_check_for_device()
334  * check if there is a i2c_device at the supplied address
335  */
336 static int cx231xx_i2c_check_for_device(struct i2c_adapter *i2c_adap,
337 					const struct i2c_msg *msg)
338 {
339 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
340 	struct cx231xx *dev = bus->dev;
341 	struct cx231xx_i2c_xfer_data req_data;
342 	int status = 0;
343 
344 	/* prepare xfer_data struct */
345 	req_data.dev_addr = msg->addr;
346 	req_data.direction = msg->flags;
347 	req_data.saddr_len = 0;
348 	req_data.saddr_dat = 0;
349 	req_data.buf_size = 0;
350 	req_data.p_buffer = NULL;
351 
352 	/* usb send command */
353 	status = dev->cx231xx_send_usb_command(bus, &req_data);
354 
355 	return status < 0 ? status : 0;
356 }
357 
358 /*
359  * cx231xx_i2c_xfer()
360  * the main i2c transfer function
361  */
362 static int cx231xx_i2c_xfer(struct i2c_adapter *i2c_adap,
363 			    struct i2c_msg msgs[], int num)
364 {
365 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
366 	struct cx231xx *dev = bus->dev;
367 	int addr, rc, i, byte;
368 
369 	if (num <= 0)
370 		return 0;
371 	mutex_lock(&dev->i2c_lock);
372 	for (i = 0; i < num; i++) {
373 
374 		addr = msgs[i].addr >> 1;
375 
376 		dprintk2(2, "%s %s addr=%x len=%d:",
377 			 (msgs[i].flags & I2C_M_RD) ? "read" : "write",
378 			 i == num - 1 ? "stop" : "nonstop", addr, msgs[i].len);
379 		if (!msgs[i].len) {
380 			/* no len: check only for device presence */
381 			rc = cx231xx_i2c_check_for_device(i2c_adap, &msgs[i]);
382 			if (rc < 0) {
383 				dprintk2(2, " no device\n");
384 				mutex_unlock(&dev->i2c_lock);
385 				return rc;
386 			}
387 
388 		} else if (msgs[i].flags & I2C_M_RD) {
389 			/* read bytes */
390 			rc = cx231xx_i2c_recv_bytes(i2c_adap, &msgs[i]);
391 			if (i2c_debug >= 2) {
392 				for (byte = 0; byte < msgs[i].len; byte++)
393 					printk(" %02x", msgs[i].buf[byte]);
394 			}
395 		} else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
396 			   msgs[i].addr == msgs[i + 1].addr
397 			   && (msgs[i].len <= 2) && (bus->nr < 3)) {
398 			/* read bytes */
399 			rc = cx231xx_i2c_recv_bytes_with_saddr(i2c_adap,
400 							       &msgs[i],
401 							       &msgs[i + 1]);
402 			if (i2c_debug >= 2) {
403 				for (byte = 0; byte < msgs[i].len; byte++)
404 					printk(" %02x", msgs[i].buf[byte]);
405 			}
406 			i++;
407 		} else {
408 			/* write bytes */
409 			if (i2c_debug >= 2) {
410 				for (byte = 0; byte < msgs[i].len; byte++)
411 					printk(" %02x", msgs[i].buf[byte]);
412 			}
413 			rc = cx231xx_i2c_send_bytes(i2c_adap, &msgs[i]);
414 		}
415 		if (rc < 0)
416 			goto err;
417 		if (i2c_debug >= 2)
418 			printk("\n");
419 	}
420 	mutex_unlock(&dev->i2c_lock);
421 	return num;
422 err:
423 	dprintk2(2, " ERROR: %i\n", rc);
424 	mutex_unlock(&dev->i2c_lock);
425 	return rc;
426 }
427 
428 /* ----------------------------------------------------------- */
429 
430 /*
431  * functionality()
432  */
433 static u32 functionality(struct i2c_adapter *adap)
434 {
435 	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
436 }
437 
438 static struct i2c_algorithm cx231xx_algo = {
439 	.master_xfer = cx231xx_i2c_xfer,
440 	.functionality = functionality,
441 };
442 
443 static struct i2c_adapter cx231xx_adap_template = {
444 	.owner = THIS_MODULE,
445 	.name = "cx231xx",
446 	.algo = &cx231xx_algo,
447 };
448 
449 static struct i2c_client cx231xx_client_template = {
450 	.name = "cx231xx internal",
451 };
452 
453 /* ----------------------------------------------------------- */
454 
455 /*
456  * i2c_devs
457  * incomplete list of known devices
458  */
459 static char *i2c_devs[128] = {
460 	[0x60 >> 1] = "colibri",
461 	[0x88 >> 1] = "hammerhead",
462 	[0x8e >> 1] = "CIR",
463 	[0x32 >> 1] = "GeminiIII",
464 	[0x02 >> 1] = "Aquarius",
465 	[0xa0 >> 1] = "eeprom",
466 	[0xc0 >> 1] = "tuner",
467 	[0xc2 >> 1] = "tuner",
468 };
469 
470 /*
471  * cx231xx_do_i2c_scan()
472  * check i2c address range for devices
473  */
474 void cx231xx_do_i2c_scan(struct cx231xx *dev, struct i2c_client *c)
475 {
476 	unsigned char buf;
477 	int i, rc;
478 
479 	cx231xx_info(": Checking for I2C devices ..\n");
480 	for (i = 0; i < 128; i++) {
481 		c->addr = i;
482 		rc = i2c_master_recv(c, &buf, 0);
483 		if (rc < 0)
484 			continue;
485 		cx231xx_info("%s: i2c scan: found device @ 0x%x  [%s]\n",
486 			     dev->name, i << 1,
487 			     i2c_devs[i] ? i2c_devs[i] : "???");
488 	}
489 	cx231xx_info(": Completed Checking for I2C devices.\n");
490 }
491 
492 /*
493  * cx231xx_i2c_register()
494  * register i2c bus
495  */
496 int cx231xx_i2c_register(struct cx231xx_i2c *bus)
497 {
498 	struct cx231xx *dev = bus->dev;
499 
500 	BUG_ON(!dev->cx231xx_send_usb_command);
501 
502 	bus->i2c_adap = cx231xx_adap_template;
503 	bus->i2c_client = cx231xx_client_template;
504 	bus->i2c_adap.dev.parent = &dev->udev->dev;
505 
506 	strlcpy(bus->i2c_adap.name, bus->dev->name, sizeof(bus->i2c_adap.name));
507 
508 	bus->i2c_adap.algo_data = bus;
509 	i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
510 	i2c_add_adapter(&bus->i2c_adap);
511 
512 	bus->i2c_client.adapter = &bus->i2c_adap;
513 
514 	if (0 == bus->i2c_rc) {
515 		if (i2c_scan)
516 			cx231xx_do_i2c_scan(dev, &bus->i2c_client);
517 	} else
518 		cx231xx_warn("%s: i2c bus %d register FAILED\n",
519 			     dev->name, bus->nr);
520 
521 	return bus->i2c_rc;
522 }
523 
524 /*
525  * cx231xx_i2c_unregister()
526  * unregister i2c_bus
527  */
528 int cx231xx_i2c_unregister(struct cx231xx_i2c *bus)
529 {
530 	i2c_del_adapter(&bus->i2c_adap);
531 	return 0;
532 }
533