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 	if (num <= 0)
380 		return 0;
381 	mutex_lock(&dev->i2c_lock);
382 	for (i = 0; i < num; i++) {
383 
384 		addr = msgs[i].addr;
385 
386 		dprintk2(2, "%s %s addr=0x%x len=%d:",
387 			 (msgs[i].flags & I2C_M_RD) ? "read" : "write",
388 			 i == num - 1 ? "stop" : "nonstop", addr, msgs[i].len);
389 		if (!msgs[i].len) {
390 			/* no len: check only for device presence */
391 			rc = cx231xx_i2c_check_for_device(i2c_adap, &msgs[i]);
392 			if (rc < 0) {
393 				dprintk2(2, " no device\n");
394 				mutex_unlock(&dev->i2c_lock);
395 				return rc;
396 			}
397 
398 		} else if (msgs[i].flags & I2C_M_RD) {
399 			/* read bytes */
400 			rc = cx231xx_i2c_recv_bytes(i2c_adap, &msgs[i]);
401 			if (i2c_debug >= 2) {
402 				for (byte = 0; byte < msgs[i].len; byte++)
403 					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
404 			}
405 		} else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
406 			   msgs[i].addr == msgs[i + 1].addr
407 			   && (msgs[i].len <= 2) && (bus->nr < 3)) {
408 			/* write bytes */
409 			if (i2c_debug >= 2) {
410 				for (byte = 0; byte < msgs[i].len; byte++)
411 					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
412 				printk(KERN_CONT "\n");
413 			}
414 			/* read bytes */
415 			dprintk2(2, "plus %s %s addr=0x%x len=%d:",
416 				(msgs[i+1].flags & I2C_M_RD) ? "read" : "write",
417 				i+1 == num - 1 ? "stop" : "nonstop", addr, msgs[i+1].len);
418 			rc = cx231xx_i2c_recv_bytes_with_saddr(i2c_adap,
419 							       &msgs[i],
420 							       &msgs[i + 1]);
421 			if (i2c_debug >= 2) {
422 				for (byte = 0; byte < msgs[i+1].len; byte++)
423 					printk(KERN_CONT " %02x", msgs[i+1].buf[byte]);
424 			}
425 			i++;
426 		} else {
427 			/* write bytes */
428 			if (i2c_debug >= 2) {
429 				for (byte = 0; byte < msgs[i].len; byte++)
430 					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
431 			}
432 			rc = cx231xx_i2c_send_bytes(i2c_adap, &msgs[i]);
433 		}
434 		if (rc < 0)
435 			goto err;
436 		if (i2c_debug >= 2)
437 			printk(KERN_CONT "\n");
438 	}
439 	mutex_unlock(&dev->i2c_lock);
440 	return num;
441 err:
442 	dprintk2(2, " ERROR: %i\n", rc);
443 	mutex_unlock(&dev->i2c_lock);
444 	return rc;
445 }
446 
447 /* ----------------------------------------------------------- */
448 
449 /*
450  * functionality()
451  */
452 static u32 functionality(struct i2c_adapter *adap)
453 {
454 	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
455 }
456 
457 static struct i2c_algorithm cx231xx_algo = {
458 	.master_xfer = cx231xx_i2c_xfer,
459 	.functionality = functionality,
460 };
461 
462 static struct i2c_adapter cx231xx_adap_template = {
463 	.owner = THIS_MODULE,
464 	.name = "cx231xx",
465 	.algo = &cx231xx_algo,
466 };
467 
468 /* ----------------------------------------------------------- */
469 
470 /*
471  * i2c_devs
472  * incomplete list of known devices
473  */
474 static const char *i2c_devs[128] = {
475 	[0x20 >> 1] = "demod",
476 	[0x60 >> 1] = "colibri",
477 	[0x88 >> 1] = "hammerhead",
478 	[0x8e >> 1] = "CIR",
479 	[0x32 >> 1] = "GeminiIII",
480 	[0x02 >> 1] = "Aquarius",
481 	[0xa0 >> 1] = "eeprom",
482 	[0xc0 >> 1] = "tuner",
483 	[0xc2 >> 1] = "tuner",
484 };
485 
486 /*
487  * cx231xx_do_i2c_scan()
488  * check i2c address range for devices
489  */
490 void cx231xx_do_i2c_scan(struct cx231xx *dev, int i2c_port)
491 {
492 	unsigned char buf;
493 	int i, rc;
494 	struct i2c_client client;
495 
496 	if (!i2c_scan)
497 		return;
498 
499 	/* Don't generate I2C errors during scan */
500 	dev->i2c_scan_running = true;
501 
502 	memset(&client, 0, sizeof(client));
503 	client.adapter = cx231xx_get_i2c_adap(dev, i2c_port);
504 
505 	for (i = 0; i < 128; i++) {
506 		client.addr = i;
507 		rc = i2c_master_recv(&client, &buf, 0);
508 		if (rc < 0)
509 			continue;
510 		dev_info(dev->dev,
511 			 "i2c scan: found device @ port %d addr 0x%x  [%s]\n",
512 			 i2c_port,
513 			 i << 1,
514 			 i2c_devs[i] ? i2c_devs[i] : "???");
515 	}
516 
517 	dev->i2c_scan_running = false;
518 }
519 
520 /*
521  * cx231xx_i2c_register()
522  * register i2c bus
523  */
524 int cx231xx_i2c_register(struct cx231xx_i2c *bus)
525 {
526 	struct cx231xx *dev = bus->dev;
527 
528 	BUG_ON(!dev->cx231xx_send_usb_command);
529 
530 	bus->i2c_adap = cx231xx_adap_template;
531 	bus->i2c_adap.dev.parent = dev->dev;
532 
533 	snprintf(bus->i2c_adap.name, sizeof(bus->i2c_adap.name), "%s-%d", bus->dev->name, bus->nr);
534 
535 	bus->i2c_adap.algo_data = bus;
536 	i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
537 	i2c_add_adapter(&bus->i2c_adap);
538 
539 	if (0 != bus->i2c_rc)
540 		dev_warn(dev->dev,
541 			 "i2c bus %d register FAILED\n", bus->nr);
542 
543 	return bus->i2c_rc;
544 }
545 
546 /*
547  * cx231xx_i2c_unregister()
548  * unregister i2c_bus
549  */
550 int cx231xx_i2c_unregister(struct cx231xx_i2c *bus)
551 {
552 	i2c_del_adapter(&bus->i2c_adap);
553 	return 0;
554 }
555 
556 /*
557  * cx231xx_i2c_mux_select()
558  * switch i2c master number 1 between port1 and port3
559  */
560 static int cx231xx_i2c_mux_select(struct i2c_adapter *adap,
561 			void *mux_priv, u32 chan_id)
562 {
563 	struct cx231xx *dev = mux_priv;
564 
565 	return cx231xx_enable_i2c_port_3(dev, chan_id);
566 }
567 
568 int cx231xx_i2c_mux_register(struct cx231xx *dev, int mux_no)
569 {
570 	struct i2c_adapter *i2c_parent = &dev->i2c_bus[1].i2c_adap;
571 	/* what is the correct mux_dev? */
572 	struct device *mux_dev = dev->dev;
573 
574 	dev->i2c_mux_adap[mux_no] = i2c_add_mux_adapter(i2c_parent,
575 				mux_dev,
576 				dev /* mux_priv */,
577 				0,
578 				mux_no /* chan_id */,
579 				0 /* class */,
580 				&cx231xx_i2c_mux_select,
581 				NULL);
582 
583 	if (!dev->i2c_mux_adap[mux_no])
584 		dev_warn(dev->dev,
585 			 "i2c mux %d register FAILED\n", mux_no);
586 
587 	return 0;
588 }
589 
590 void cx231xx_i2c_mux_unregister(struct cx231xx *dev, int mux_no)
591 {
592 	i2c_del_mux_adapter(dev->i2c_mux_adap[mux_no]);
593 	dev->i2c_mux_adap[mux_no] = NULL;
594 }
595 
596 struct i2c_adapter *cx231xx_get_i2c_adap(struct cx231xx *dev, int i2c_port)
597 {
598 	switch (i2c_port) {
599 	case I2C_0:
600 		return &dev->i2c_bus[0].i2c_adap;
601 	case I2C_1:
602 		return &dev->i2c_bus[1].i2c_adap;
603 	case I2C_2:
604 		return &dev->i2c_bus[2].i2c_adap;
605 	case I2C_1_MUX_1:
606 		return dev->i2c_mux_adap[0];
607 	case I2C_1_MUX_3:
608 		return dev->i2c_mux_adap[1];
609 	default:
610 		return NULL;
611 	}
612 }
613 EXPORT_SYMBOL_GPL(cx231xx_get_i2c_adap);
614