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 "cx231xx.h"
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/i2c.h>
27 #include <linux/i2c-mux.h>
28 #include <media/v4l2-common.h>
29 #include <media/tuner.h>
30 
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 int get_real_i2c_port(struct cx231xx *dev, int bus_nr)
58 {
59 	if (bus_nr == 1)
60 		return dev->port_3_switch_enabled ? I2C_1_MUX_3 : I2C_1_MUX_1;
61 	return bus_nr;
62 }
63 
64 static inline bool is_tuner(struct cx231xx *dev, struct cx231xx_i2c *bus,
65 			const struct i2c_msg *msg, int tuner_type)
66 {
67 	int i2c_port = get_real_i2c_port(dev, bus->nr);
68 
69 	if (i2c_port != dev->board.tuner_i2c_master)
70 		return false;
71 
72 	if (msg->addr != dev->board.tuner_addr)
73 		return false;
74 
75 	if (dev->tuner_type != tuner_type)
76 		return false;
77 
78 	return true;
79 }
80 
81 /*
82  * cx231xx_i2c_send_bytes()
83  */
84 static int cx231xx_i2c_send_bytes(struct i2c_adapter *i2c_adap,
85 				  const struct i2c_msg *msg)
86 {
87 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
88 	struct cx231xx *dev = bus->dev;
89 	struct cx231xx_i2c_xfer_data req_data;
90 	int status = 0;
91 	u16 size = 0;
92 	u8 loop = 0;
93 	u8 saddr_len = 1;
94 	u8 *buf_ptr = NULL;
95 	u16 saddr = 0;
96 	u8 need_gpio = 0;
97 
98 	if (is_tuner(dev, bus, msg, TUNER_XC5000)) {
99 		size = msg->len;
100 
101 		if (size == 2) {	/* register write sub addr */
102 			/* Just writing sub address will cause problem
103 			* to XC5000. So ignore the request */
104 			return 0;
105 		} else if (size == 4) {	/* register write with sub addr */
106 			if (msg->len >= 2)
107 				saddr = msg->buf[0] << 8 | msg->buf[1];
108 			else if (msg->len == 1)
109 				saddr = msg->buf[0];
110 
111 			switch (saddr) {
112 			case 0x0000:	/* start tuner calibration mode */
113 				need_gpio = 1;
114 				/* FW Loading is done */
115 				dev->xc_fw_load_done = 1;
116 				break;
117 			case 0x000D:	/* Set signal source */
118 			case 0x0001:	/* Set TV standard - Video */
119 			case 0x0002:	/* Set TV standard - Audio */
120 			case 0x0003:	/* Set RF Frequency */
121 				need_gpio = 1;
122 				break;
123 			default:
124 				if (dev->xc_fw_load_done)
125 					need_gpio = 1;
126 				break;
127 			}
128 
129 			if (need_gpio) {
130 				dprintk1(1,
131 				"GPIO WRITE: addr 0x%x, len %d, saddr 0x%x\n",
132 				msg->addr, msg->len, saddr);
133 
134 				return dev->cx231xx_gpio_i2c_write(dev,
135 								   msg->addr,
136 								   msg->buf,
137 								   msg->len);
138 			}
139 		}
140 
141 		/* special case for Xc5000 tuner case */
142 		saddr_len = 1;
143 
144 		/* adjust the length to correct length */
145 		size -= saddr_len;
146 		buf_ptr = (u8 *) (msg->buf + 1);
147 
148 		do {
149 			/* prepare xfer_data struct */
150 			req_data.dev_addr = msg->addr;
151 			req_data.direction = msg->flags;
152 			req_data.saddr_len = saddr_len;
153 			req_data.saddr_dat = msg->buf[0];
154 			req_data.buf_size = size > 16 ? 16 : size;
155 			req_data.p_buffer = (u8 *) (buf_ptr + loop * 16);
156 
157 			bus->i2c_nostop = (size > 16) ? 1 : 0;
158 			bus->i2c_reserve = (loop == 0) ? 0 : 1;
159 
160 			/* usb send command */
161 			status = dev->cx231xx_send_usb_command(bus, &req_data);
162 			loop++;
163 
164 			if (size >= 16)
165 				size -= 16;
166 			else
167 				size = 0;
168 
169 		} while (size > 0);
170 
171 		bus->i2c_nostop = 0;
172 		bus->i2c_reserve = 0;
173 
174 	} else {		/* regular case */
175 
176 		/* prepare xfer_data struct */
177 		req_data.dev_addr = msg->addr;
178 		req_data.direction = msg->flags;
179 		req_data.saddr_len = 0;
180 		req_data.saddr_dat = 0;
181 		req_data.buf_size = msg->len;
182 		req_data.p_buffer = msg->buf;
183 
184 		/* usb send command */
185 		status = dev->cx231xx_send_usb_command(bus, &req_data);
186 	}
187 
188 	return status < 0 ? status : 0;
189 }
190 
191 /*
192  * cx231xx_i2c_recv_bytes()
193  * read a byte from the i2c device
194  */
195 static int cx231xx_i2c_recv_bytes(struct i2c_adapter *i2c_adap,
196 				  const struct i2c_msg *msg)
197 {
198 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
199 	struct cx231xx *dev = bus->dev;
200 	struct cx231xx_i2c_xfer_data req_data;
201 	int status = 0;
202 	u16 saddr = 0;
203 	u8 need_gpio = 0;
204 
205 	if (is_tuner(dev, bus, msg, TUNER_XC5000)) {
206 		if (msg->len == 2)
207 			saddr = msg->buf[0] << 8 | msg->buf[1];
208 		else if (msg->len == 1)
209 			saddr = msg->buf[0];
210 
211 		if (dev->xc_fw_load_done) {
212 
213 			switch (saddr) {
214 			case 0x0009:	/* BUSY check */
215 				dprintk1(1,
216 				"GPIO R E A D: Special case BUSY check \n");
217 				/*Try read BUSY register, just set it to zero*/
218 				msg->buf[0] = 0;
219 				if (msg->len == 2)
220 					msg->buf[1] = 0;
221 				return 0;
222 			case 0x0004:	/* read Lock status */
223 				need_gpio = 1;
224 				break;
225 
226 			}
227 
228 			if (need_gpio) {
229 				/* this is a special case to handle Xceive tuner
230 				clock stretch issue with gpio based I2C */
231 
232 				dprintk1(1,
233 				"GPIO R E A D: addr 0x%x, len %d, saddr 0x%x\n",
234 				msg->addr, msg->len,
235 				msg->buf[0] << 8 | msg->buf[1]);
236 
237 				status =
238 				    dev->cx231xx_gpio_i2c_write(dev, msg->addr,
239 								msg->buf,
240 								msg->len);
241 				status =
242 				    dev->cx231xx_gpio_i2c_read(dev, msg->addr,
243 							       msg->buf,
244 							       msg->len);
245 				return status;
246 			}
247 		}
248 
249 		/* prepare xfer_data struct */
250 		req_data.dev_addr = msg->addr;
251 		req_data.direction = msg->flags;
252 		req_data.saddr_len = msg->len;
253 		req_data.saddr_dat = msg->buf[0] << 8 | msg->buf[1];
254 		req_data.buf_size = msg->len;
255 		req_data.p_buffer = msg->buf;
256 
257 		/* usb send command */
258 		status = dev->cx231xx_send_usb_command(bus, &req_data);
259 
260 	} else {
261 
262 		/* prepare xfer_data struct */
263 		req_data.dev_addr = msg->addr;
264 		req_data.direction = msg->flags;
265 		req_data.saddr_len = 0;
266 		req_data.saddr_dat = 0;
267 		req_data.buf_size = msg->len;
268 		req_data.p_buffer = msg->buf;
269 
270 		/* usb send command */
271 		status = dev->cx231xx_send_usb_command(bus, &req_data);
272 	}
273 
274 	return status < 0 ? status : 0;
275 }
276 
277 /*
278  * cx231xx_i2c_recv_bytes_with_saddr()
279  * read a byte from the i2c device
280  */
281 static int cx231xx_i2c_recv_bytes_with_saddr(struct i2c_adapter *i2c_adap,
282 					     const struct i2c_msg *msg1,
283 					     const struct i2c_msg *msg2)
284 {
285 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
286 	struct cx231xx *dev = bus->dev;
287 	struct cx231xx_i2c_xfer_data req_data;
288 	int status = 0;
289 	u16 saddr = 0;
290 	u8 need_gpio = 0;
291 
292 	if (msg1->len == 2)
293 		saddr = msg1->buf[0] << 8 | msg1->buf[1];
294 	else if (msg1->len == 1)
295 		saddr = msg1->buf[0];
296 
297 	if (is_tuner(dev, bus, msg2, TUNER_XC5000)) {
298 		if ((msg2->len < 16)) {
299 
300 			dprintk1(1,
301 			"i2c_read: addr 0x%x, len %d, saddr 0x%x, len %d\n",
302 			msg2->addr, msg2->len, saddr, msg1->len);
303 
304 			switch (saddr) {
305 			case 0x0008:	/* read FW load status */
306 				need_gpio = 1;
307 				break;
308 			case 0x0004:	/* read Lock status */
309 				need_gpio = 1;
310 				break;
311 			}
312 
313 			if (need_gpio) {
314 				status =
315 				    dev->cx231xx_gpio_i2c_write(dev, msg1->addr,
316 								msg1->buf,
317 								msg1->len);
318 				status =
319 				    dev->cx231xx_gpio_i2c_read(dev, msg2->addr,
320 							       msg2->buf,
321 							       msg2->len);
322 				return status;
323 			}
324 		}
325 	}
326 
327 	/* prepare xfer_data struct */
328 	req_data.dev_addr = msg2->addr;
329 	req_data.direction = msg2->flags;
330 	req_data.saddr_len = msg1->len;
331 	req_data.saddr_dat = saddr;
332 	req_data.buf_size = msg2->len;
333 	req_data.p_buffer = msg2->buf;
334 
335 	/* usb send command */
336 	status = dev->cx231xx_send_usb_command(bus, &req_data);
337 
338 	return status < 0 ? status : 0;
339 }
340 
341 /*
342  * cx231xx_i2c_check_for_device()
343  * check if there is a i2c_device at the supplied address
344  */
345 static int cx231xx_i2c_check_for_device(struct i2c_adapter *i2c_adap,
346 					const struct i2c_msg *msg)
347 {
348 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
349 	struct cx231xx *dev = bus->dev;
350 	struct cx231xx_i2c_xfer_data req_data;
351 	int status = 0;
352 	u8 buf[1];
353 
354 	/* prepare xfer_data struct */
355 	req_data.dev_addr = msg->addr;
356 	req_data.direction = I2C_M_RD;
357 	req_data.saddr_len = 0;
358 	req_data.saddr_dat = 0;
359 	req_data.buf_size = 1;
360 	req_data.p_buffer = buf;
361 
362 	/* usb send command */
363 	status = dev->cx231xx_send_usb_command(bus, &req_data);
364 
365 	return status < 0 ? status : 0;
366 }
367 
368 /*
369  * cx231xx_i2c_xfer()
370  * the main i2c transfer function
371  */
372 static int cx231xx_i2c_xfer(struct i2c_adapter *i2c_adap,
373 			    struct i2c_msg msgs[], int num)
374 {
375 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
376 	struct cx231xx *dev = bus->dev;
377 	int addr, rc, i, byte;
378 
379 	mutex_lock(&dev->i2c_lock);
380 	for (i = 0; i < num; i++) {
381 
382 		addr = msgs[i].addr;
383 
384 		dprintk2(2, "%s %s addr=0x%x len=%d:",
385 			 (msgs[i].flags & I2C_M_RD) ? "read" : "write",
386 			 i == num - 1 ? "stop" : "nonstop", addr, msgs[i].len);
387 		if (!msgs[i].len) {
388 			/* no len: check only for device presence */
389 			rc = cx231xx_i2c_check_for_device(i2c_adap, &msgs[i]);
390 			if (rc < 0) {
391 				dprintk2(2, " no device\n");
392 				mutex_unlock(&dev->i2c_lock);
393 				return rc;
394 			}
395 
396 		} else if (msgs[i].flags & I2C_M_RD) {
397 			/* read bytes */
398 			rc = cx231xx_i2c_recv_bytes(i2c_adap, &msgs[i]);
399 			if (i2c_debug >= 2) {
400 				for (byte = 0; byte < msgs[i].len; byte++)
401 					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
402 			}
403 		} else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
404 			   msgs[i].addr == msgs[i + 1].addr
405 			   && (msgs[i].len <= 2) && (bus->nr < 3)) {
406 			/* write bytes */
407 			if (i2c_debug >= 2) {
408 				for (byte = 0; byte < msgs[i].len; byte++)
409 					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
410 				printk(KERN_CONT "\n");
411 			}
412 			/* read bytes */
413 			dprintk2(2, "plus %s %s addr=0x%x len=%d:",
414 				(msgs[i+1].flags & I2C_M_RD) ? "read" : "write",
415 				i+1 == num - 1 ? "stop" : "nonstop", addr, msgs[i+1].len);
416 			rc = cx231xx_i2c_recv_bytes_with_saddr(i2c_adap,
417 							       &msgs[i],
418 							       &msgs[i + 1]);
419 			if (i2c_debug >= 2) {
420 				for (byte = 0; byte < msgs[i+1].len; byte++)
421 					printk(KERN_CONT " %02x", msgs[i+1].buf[byte]);
422 			}
423 			i++;
424 		} else {
425 			/* write bytes */
426 			if (i2c_debug >= 2) {
427 				for (byte = 0; byte < msgs[i].len; byte++)
428 					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
429 			}
430 			rc = cx231xx_i2c_send_bytes(i2c_adap, &msgs[i]);
431 		}
432 		if (rc < 0)
433 			goto err;
434 		if (i2c_debug >= 2)
435 			printk(KERN_CONT "\n");
436 	}
437 	mutex_unlock(&dev->i2c_lock);
438 	return num;
439 err:
440 	dprintk2(2, " ERROR: %i\n", rc);
441 	mutex_unlock(&dev->i2c_lock);
442 	return rc;
443 }
444 
445 /* ----------------------------------------------------------- */
446 
447 /*
448  * functionality()
449  */
450 static u32 functionality(struct i2c_adapter *adap)
451 {
452 	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
453 }
454 
455 static const struct i2c_algorithm cx231xx_algo = {
456 	.master_xfer = cx231xx_i2c_xfer,
457 	.functionality = functionality,
458 };
459 
460 static const struct i2c_adapter cx231xx_adap_template = {
461 	.owner = THIS_MODULE,
462 	.name = "cx231xx",
463 	.algo = &cx231xx_algo,
464 };
465 
466 /* ----------------------------------------------------------- */
467 
468 /*
469  * i2c_devs
470  * incomplete list of known devices
471  */
472 static const char *i2c_devs[128] = {
473 	[0x20 >> 1] = "demod",
474 	[0x60 >> 1] = "colibri",
475 	[0x88 >> 1] = "hammerhead",
476 	[0x8e >> 1] = "CIR",
477 	[0x32 >> 1] = "GeminiIII",
478 	[0x02 >> 1] = "Aquarius",
479 	[0xa0 >> 1] = "eeprom",
480 	[0xc0 >> 1] = "tuner",
481 	[0xc2 >> 1] = "tuner",
482 };
483 
484 /*
485  * cx231xx_do_i2c_scan()
486  * check i2c address range for devices
487  */
488 void cx231xx_do_i2c_scan(struct cx231xx *dev, int i2c_port)
489 {
490 	unsigned char buf;
491 	int i, rc;
492 	struct i2c_adapter *adap;
493 	struct i2c_msg msg = {
494 		.flags = I2C_M_RD,
495 		.len = 1,
496 		.buf = &buf,
497 	};
498 
499 	if (!i2c_scan)
500 		return;
501 
502 	/* Don't generate I2C errors during scan */
503 	dev->i2c_scan_running = true;
504 	adap = cx231xx_get_i2c_adap(dev, i2c_port);
505 
506 	for (i = 0; i < 128; i++) {
507 		msg.addr = i;
508 		rc = i2c_transfer(adap, &msg, 1);
509 
510 		if (rc < 0)
511 			continue;
512 		dev_info(dev->dev,
513 			 "i2c scan: found device @ port %d addr 0x%x  [%s]\n",
514 			 i2c_port,
515 			 i << 1,
516 			 i2c_devs[i] ? i2c_devs[i] : "???");
517 	}
518 
519 	dev->i2c_scan_running = false;
520 }
521 
522 /*
523  * cx231xx_i2c_register()
524  * register i2c bus
525  */
526 int cx231xx_i2c_register(struct cx231xx_i2c *bus)
527 {
528 	struct cx231xx *dev = bus->dev;
529 
530 	BUG_ON(!dev->cx231xx_send_usb_command);
531 
532 	bus->i2c_adap = cx231xx_adap_template;
533 	bus->i2c_adap.dev.parent = dev->dev;
534 
535 	snprintf(bus->i2c_adap.name, sizeof(bus->i2c_adap.name), "%s-%d", bus->dev->name, bus->nr);
536 
537 	bus->i2c_adap.algo_data = bus;
538 	i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
539 	bus->i2c_rc = i2c_add_adapter(&bus->i2c_adap);
540 
541 	if (0 != bus->i2c_rc)
542 		dev_warn(dev->dev,
543 			 "i2c bus %d register FAILED\n", bus->nr);
544 
545 	return bus->i2c_rc;
546 }
547 
548 /*
549  * cx231xx_i2c_unregister()
550  * unregister i2c_bus
551  */
552 void cx231xx_i2c_unregister(struct cx231xx_i2c *bus)
553 {
554 	if (!bus->i2c_rc)
555 		i2c_del_adapter(&bus->i2c_adap);
556 }
557 
558 /*
559  * cx231xx_i2c_mux_select()
560  * switch i2c master number 1 between port1 and port3
561  */
562 static int cx231xx_i2c_mux_select(struct i2c_mux_core *muxc, u32 chan_id)
563 {
564 	struct cx231xx *dev = i2c_mux_priv(muxc);
565 
566 	return cx231xx_enable_i2c_port_3(dev, chan_id);
567 }
568 
569 int cx231xx_i2c_mux_create(struct cx231xx *dev)
570 {
571 	dev->muxc = i2c_mux_alloc(&dev->i2c_bus[1].i2c_adap, dev->dev, 2, 0, 0,
572 				  cx231xx_i2c_mux_select, NULL);
573 	if (!dev->muxc)
574 		return -ENOMEM;
575 	dev->muxc->priv = dev;
576 	return 0;
577 }
578 
579 int cx231xx_i2c_mux_register(struct cx231xx *dev, int mux_no)
580 {
581 	return i2c_mux_add_adapter(dev->muxc,
582 				   0,
583 				   mux_no /* chan_id */,
584 				   0 /* class */);
585 }
586 
587 void cx231xx_i2c_mux_unregister(struct cx231xx *dev)
588 {
589 	i2c_mux_del_adapters(dev->muxc);
590 }
591 
592 struct i2c_adapter *cx231xx_get_i2c_adap(struct cx231xx *dev, int i2c_port)
593 {
594 	switch (i2c_port) {
595 	case I2C_0:
596 		return &dev->i2c_bus[0].i2c_adap;
597 	case I2C_1:
598 		return &dev->i2c_bus[1].i2c_adap;
599 	case I2C_2:
600 		return &dev->i2c_bus[2].i2c_adap;
601 	case I2C_1_MUX_1:
602 		return dev->muxc->adapter[0];
603 	case I2C_1_MUX_3:
604 		return dev->muxc->adapter[1];
605 	default:
606 		BUG();
607 	}
608 }
609 EXPORT_SYMBOL_GPL(cx231xx_get_i2c_adap);
610