1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3    cx231xx-i2c.c - driver for Conexant Cx23100/101/102 USB video capture devices
4 
5    Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
6 		Based on em28xx driver
7 		Based on Cx23885 driver
8 
9  */
10 
11 #include "cx231xx.h"
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/i2c.h>
15 #include <linux/i2c-mux.h>
16 #include <media/v4l2-common.h>
17 #include <media/tuner.h>
18 
19 
20 /* ----------------------------------------------------------- */
21 
22 static unsigned int i2c_scan;
23 module_param(i2c_scan, int, 0444);
24 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
25 
26 static unsigned int i2c_debug;
27 module_param(i2c_debug, int, 0644);
28 MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
29 
30 #define dprintk1(lvl, fmt, args...)			\
31 do {							\
32 	if (i2c_debug >= lvl) {				\
33 		printk(fmt, ##args);			\
34 		}					\
35 } while (0)
36 
37 #define dprintk2(lvl, fmt, args...)			\
38 do {							\
39 	if (i2c_debug >= lvl) {				\
40 		printk(KERN_DEBUG "%s at %s: " fmt,	\
41 		       dev->name, __func__ , ##args);	\
42       }							\
43 } while (0)
44 
45 static inline int get_real_i2c_port(struct cx231xx *dev, int bus_nr)
46 {
47 	if (bus_nr == 1)
48 		return dev->port_3_switch_enabled ? I2C_1_MUX_3 : I2C_1_MUX_1;
49 	return bus_nr;
50 }
51 
52 static inline bool is_tuner(struct cx231xx *dev, struct cx231xx_i2c *bus,
53 			const struct i2c_msg *msg, int tuner_type)
54 {
55 	int i2c_port = get_real_i2c_port(dev, bus->nr);
56 
57 	if (i2c_port != dev->board.tuner_i2c_master)
58 		return false;
59 
60 	if (msg->addr != dev->board.tuner_addr)
61 		return false;
62 
63 	if (dev->tuner_type != tuner_type)
64 		return false;
65 
66 	return true;
67 }
68 
69 /*
70  * cx231xx_i2c_send_bytes()
71  */
72 static int cx231xx_i2c_send_bytes(struct i2c_adapter *i2c_adap,
73 				  const struct i2c_msg *msg)
74 {
75 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
76 	struct cx231xx *dev = bus->dev;
77 	struct cx231xx_i2c_xfer_data req_data;
78 	int status = 0;
79 	u16 size = 0;
80 	u8 loop = 0;
81 	u8 saddr_len = 1;
82 	u8 *buf_ptr = NULL;
83 	u16 saddr = 0;
84 	u8 need_gpio = 0;
85 
86 	if (is_tuner(dev, bus, msg, TUNER_XC5000)) {
87 		size = msg->len;
88 
89 		if (size == 2) {	/* register write sub addr */
90 			/* Just writing sub address will cause problem
91 			* to XC5000. So ignore the request */
92 			return 0;
93 		} else if (size == 4) {	/* register write with sub addr */
94 			if (msg->len >= 2)
95 				saddr = msg->buf[0] << 8 | msg->buf[1];
96 			else if (msg->len == 1)
97 				saddr = msg->buf[0];
98 
99 			switch (saddr) {
100 			case 0x0000:	/* start tuner calibration mode */
101 				need_gpio = 1;
102 				/* FW Loading is done */
103 				dev->xc_fw_load_done = 1;
104 				break;
105 			case 0x000D:	/* Set signal source */
106 			case 0x0001:	/* Set TV standard - Video */
107 			case 0x0002:	/* Set TV standard - Audio */
108 			case 0x0003:	/* Set RF Frequency */
109 				need_gpio = 1;
110 				break;
111 			default:
112 				if (dev->xc_fw_load_done)
113 					need_gpio = 1;
114 				break;
115 			}
116 
117 			if (need_gpio) {
118 				dprintk1(1,
119 				"GPIO WRITE: addr 0x%x, len %d, saddr 0x%x\n",
120 				msg->addr, msg->len, saddr);
121 
122 				return dev->cx231xx_gpio_i2c_write(dev,
123 								   msg->addr,
124 								   msg->buf,
125 								   msg->len);
126 			}
127 		}
128 
129 		/* special case for Xc5000 tuner case */
130 		saddr_len = 1;
131 
132 		/* adjust the length to correct length */
133 		size -= saddr_len;
134 		buf_ptr = (u8 *) (msg->buf + 1);
135 
136 		do {
137 			/* prepare xfer_data struct */
138 			req_data.dev_addr = msg->addr;
139 			req_data.direction = msg->flags;
140 			req_data.saddr_len = saddr_len;
141 			req_data.saddr_dat = msg->buf[0];
142 			req_data.buf_size = size > 16 ? 16 : size;
143 			req_data.p_buffer = (u8 *) (buf_ptr + loop * 16);
144 
145 			bus->i2c_nostop = (size > 16) ? 1 : 0;
146 			bus->i2c_reserve = (loop == 0) ? 0 : 1;
147 
148 			/* usb send command */
149 			status = dev->cx231xx_send_usb_command(bus, &req_data);
150 			loop++;
151 
152 			if (size >= 16)
153 				size -= 16;
154 			else
155 				size = 0;
156 
157 		} while (size > 0);
158 
159 		bus->i2c_nostop = 0;
160 		bus->i2c_reserve = 0;
161 
162 	} else {		/* regular case */
163 
164 		/* prepare xfer_data struct */
165 		req_data.dev_addr = msg->addr;
166 		req_data.direction = msg->flags;
167 		req_data.saddr_len = 0;
168 		req_data.saddr_dat = 0;
169 		req_data.buf_size = msg->len;
170 		req_data.p_buffer = msg->buf;
171 
172 		/* usb send command */
173 		status = dev->cx231xx_send_usb_command(bus, &req_data);
174 	}
175 
176 	return status < 0 ? status : 0;
177 }
178 
179 /*
180  * cx231xx_i2c_recv_bytes()
181  * read a byte from the i2c device
182  */
183 static int cx231xx_i2c_recv_bytes(struct i2c_adapter *i2c_adap,
184 				  const struct i2c_msg *msg)
185 {
186 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
187 	struct cx231xx *dev = bus->dev;
188 	struct cx231xx_i2c_xfer_data req_data;
189 	int status = 0;
190 	u16 saddr = 0;
191 	u8 need_gpio = 0;
192 
193 	if (is_tuner(dev, bus, msg, TUNER_XC5000)) {
194 		if (msg->len == 2)
195 			saddr = msg->buf[0] << 8 | msg->buf[1];
196 		else if (msg->len == 1)
197 			saddr = msg->buf[0];
198 
199 		if (dev->xc_fw_load_done) {
200 
201 			switch (saddr) {
202 			case 0x0009:	/* BUSY check */
203 				dprintk1(1,
204 				"GPIO R E A D: Special case BUSY check \n");
205 				/*Try read BUSY register, just set it to zero*/
206 				msg->buf[0] = 0;
207 				if (msg->len == 2)
208 					msg->buf[1] = 0;
209 				return 0;
210 			case 0x0004:	/* read Lock status */
211 				need_gpio = 1;
212 				break;
213 
214 			}
215 
216 			if (need_gpio) {
217 				/* this is a special case to handle Xceive tuner
218 				clock stretch issue with gpio based I2C */
219 
220 				dprintk1(1,
221 				"GPIO R E A D: addr 0x%x, len %d, saddr 0x%x\n",
222 				msg->addr, msg->len,
223 				msg->buf[0] << 8 | msg->buf[1]);
224 
225 				status =
226 				    dev->cx231xx_gpio_i2c_write(dev, msg->addr,
227 								msg->buf,
228 								msg->len);
229 				status =
230 				    dev->cx231xx_gpio_i2c_read(dev, msg->addr,
231 							       msg->buf,
232 							       msg->len);
233 				return status;
234 			}
235 		}
236 
237 		/* prepare xfer_data struct */
238 		req_data.dev_addr = msg->addr;
239 		req_data.direction = msg->flags;
240 		req_data.saddr_len = msg->len;
241 		req_data.saddr_dat = msg->buf[0] << 8 | msg->buf[1];
242 		req_data.buf_size = msg->len;
243 		req_data.p_buffer = msg->buf;
244 
245 		/* usb send command */
246 		status = dev->cx231xx_send_usb_command(bus, &req_data);
247 
248 	} else {
249 
250 		/* prepare xfer_data struct */
251 		req_data.dev_addr = msg->addr;
252 		req_data.direction = msg->flags;
253 		req_data.saddr_len = 0;
254 		req_data.saddr_dat = 0;
255 		req_data.buf_size = msg->len;
256 		req_data.p_buffer = msg->buf;
257 
258 		/* usb send command */
259 		status = dev->cx231xx_send_usb_command(bus, &req_data);
260 	}
261 
262 	return status < 0 ? status : 0;
263 }
264 
265 /*
266  * cx231xx_i2c_recv_bytes_with_saddr()
267  * read a byte from the i2c device
268  */
269 static int cx231xx_i2c_recv_bytes_with_saddr(struct i2c_adapter *i2c_adap,
270 					     const struct i2c_msg *msg1,
271 					     const struct i2c_msg *msg2)
272 {
273 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
274 	struct cx231xx *dev = bus->dev;
275 	struct cx231xx_i2c_xfer_data req_data;
276 	int status = 0;
277 	u16 saddr = 0;
278 	u8 need_gpio = 0;
279 
280 	if (msg1->len == 2)
281 		saddr = msg1->buf[0] << 8 | msg1->buf[1];
282 	else if (msg1->len == 1)
283 		saddr = msg1->buf[0];
284 
285 	if (is_tuner(dev, bus, msg2, TUNER_XC5000)) {
286 		if ((msg2->len < 16)) {
287 
288 			dprintk1(1,
289 			"i2c_read: addr 0x%x, len %d, saddr 0x%x, len %d\n",
290 			msg2->addr, msg2->len, saddr, msg1->len);
291 
292 			switch (saddr) {
293 			case 0x0008:	/* read FW load status */
294 				need_gpio = 1;
295 				break;
296 			case 0x0004:	/* read Lock status */
297 				need_gpio = 1;
298 				break;
299 			}
300 
301 			if (need_gpio) {
302 				status =
303 				    dev->cx231xx_gpio_i2c_write(dev, msg1->addr,
304 								msg1->buf,
305 								msg1->len);
306 				status =
307 				    dev->cx231xx_gpio_i2c_read(dev, msg2->addr,
308 							       msg2->buf,
309 							       msg2->len);
310 				return status;
311 			}
312 		}
313 	}
314 
315 	/* prepare xfer_data struct */
316 	req_data.dev_addr = msg2->addr;
317 	req_data.direction = msg2->flags;
318 	req_data.saddr_len = msg1->len;
319 	req_data.saddr_dat = saddr;
320 	req_data.buf_size = msg2->len;
321 	req_data.p_buffer = msg2->buf;
322 
323 	/* usb send command */
324 	status = dev->cx231xx_send_usb_command(bus, &req_data);
325 
326 	return status < 0 ? status : 0;
327 }
328 
329 /*
330  * cx231xx_i2c_check_for_device()
331  * check if there is a i2c_device at the supplied address
332  */
333 static int cx231xx_i2c_check_for_device(struct i2c_adapter *i2c_adap,
334 					const struct i2c_msg *msg)
335 {
336 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
337 	struct cx231xx *dev = bus->dev;
338 	struct cx231xx_i2c_xfer_data req_data;
339 	int status = 0;
340 	u8 buf[1];
341 
342 	/* prepare xfer_data struct */
343 	req_data.dev_addr = msg->addr;
344 	req_data.direction = I2C_M_RD;
345 	req_data.saddr_len = 0;
346 	req_data.saddr_dat = 0;
347 	req_data.buf_size = 1;
348 	req_data.p_buffer = buf;
349 
350 	/* usb send command */
351 	status = dev->cx231xx_send_usb_command(bus, &req_data);
352 
353 	return status < 0 ? status : 0;
354 }
355 
356 /*
357  * cx231xx_i2c_xfer()
358  * the main i2c transfer function
359  */
360 static int cx231xx_i2c_xfer(struct i2c_adapter *i2c_adap,
361 			    struct i2c_msg msgs[], int num)
362 {
363 	struct cx231xx_i2c *bus = i2c_adap->algo_data;
364 	struct cx231xx *dev = bus->dev;
365 	int addr, rc, i, byte;
366 
367 	mutex_lock(&dev->i2c_lock);
368 	for (i = 0; i < num; i++) {
369 
370 		addr = msgs[i].addr;
371 
372 		dprintk2(2, "%s %s addr=0x%x len=%d:",
373 			 (msgs[i].flags & I2C_M_RD) ? "read" : "write",
374 			 i == num - 1 ? "stop" : "nonstop", addr, msgs[i].len);
375 		if (!msgs[i].len) {
376 			/* no len: check only for device presence */
377 			rc = cx231xx_i2c_check_for_device(i2c_adap, &msgs[i]);
378 			if (rc < 0) {
379 				dprintk2(2, " no device\n");
380 				mutex_unlock(&dev->i2c_lock);
381 				return rc;
382 			}
383 
384 		} else if (msgs[i].flags & I2C_M_RD) {
385 			/* read bytes */
386 			rc = cx231xx_i2c_recv_bytes(i2c_adap, &msgs[i]);
387 			if (i2c_debug >= 2) {
388 				for (byte = 0; byte < msgs[i].len; byte++)
389 					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
390 			}
391 		} else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
392 			   msgs[i].addr == msgs[i + 1].addr
393 			   && (msgs[i].len <= 2) && (bus->nr < 3)) {
394 			/* write bytes */
395 			if (i2c_debug >= 2) {
396 				for (byte = 0; byte < msgs[i].len; byte++)
397 					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
398 				printk(KERN_CONT "\n");
399 			}
400 			/* read bytes */
401 			dprintk2(2, "plus %s %s addr=0x%x len=%d:",
402 				(msgs[i+1].flags & I2C_M_RD) ? "read" : "write",
403 				i+1 == num - 1 ? "stop" : "nonstop", addr, msgs[i+1].len);
404 			rc = cx231xx_i2c_recv_bytes_with_saddr(i2c_adap,
405 							       &msgs[i],
406 							       &msgs[i + 1]);
407 			if (i2c_debug >= 2) {
408 				for (byte = 0; byte < msgs[i+1].len; byte++)
409 					printk(KERN_CONT " %02x", msgs[i+1].buf[byte]);
410 			}
411 			i++;
412 		} else {
413 			/* write bytes */
414 			if (i2c_debug >= 2) {
415 				for (byte = 0; byte < msgs[i].len; byte++)
416 					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
417 			}
418 			rc = cx231xx_i2c_send_bytes(i2c_adap, &msgs[i]);
419 		}
420 		if (rc < 0)
421 			goto err;
422 		if (i2c_debug >= 2)
423 			printk(KERN_CONT "\n");
424 	}
425 	mutex_unlock(&dev->i2c_lock);
426 	return num;
427 err:
428 	dprintk2(2, " ERROR: %i\n", rc);
429 	mutex_unlock(&dev->i2c_lock);
430 	return rc;
431 }
432 
433 /* ----------------------------------------------------------- */
434 
435 /*
436  * functionality()
437  */
438 static u32 functionality(struct i2c_adapter *adap)
439 {
440 	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
441 }
442 
443 static const struct i2c_algorithm cx231xx_algo = {
444 	.master_xfer = cx231xx_i2c_xfer,
445 	.functionality = functionality,
446 };
447 
448 static const struct i2c_adapter cx231xx_adap_template = {
449 	.owner = THIS_MODULE,
450 	.name = "cx231xx",
451 	.algo = &cx231xx_algo,
452 };
453 
454 /* ----------------------------------------------------------- */
455 
456 /*
457  * i2c_devs
458  * incomplete list of known devices
459  */
460 static const char *i2c_devs[128] = {
461 	[0x20 >> 1] = "demod",
462 	[0x60 >> 1] = "colibri",
463 	[0x88 >> 1] = "hammerhead",
464 	[0x8e >> 1] = "CIR",
465 	[0x32 >> 1] = "GeminiIII",
466 	[0x02 >> 1] = "Aquarius",
467 	[0xa0 >> 1] = "eeprom",
468 	[0xc0 >> 1] = "tuner",
469 	[0xc2 >> 1] = "tuner",
470 };
471 
472 /*
473  * cx231xx_do_i2c_scan()
474  * check i2c address range for devices
475  */
476 void cx231xx_do_i2c_scan(struct cx231xx *dev, int i2c_port)
477 {
478 	unsigned char buf;
479 	int i, rc;
480 	struct i2c_adapter *adap;
481 	struct i2c_msg msg = {
482 		.flags = I2C_M_RD,
483 		.len = 1,
484 		.buf = &buf,
485 	};
486 
487 	if (!i2c_scan)
488 		return;
489 
490 	/* Don't generate I2C errors during scan */
491 	dev->i2c_scan_running = true;
492 	adap = cx231xx_get_i2c_adap(dev, i2c_port);
493 
494 	for (i = 0; i < 128; i++) {
495 		msg.addr = i;
496 		rc = i2c_transfer(adap, &msg, 1);
497 
498 		if (rc < 0)
499 			continue;
500 		dev_info(dev->dev,
501 			 "i2c scan: found device @ port %d addr 0x%x  [%s]\n",
502 			 i2c_port,
503 			 i << 1,
504 			 i2c_devs[i] ? i2c_devs[i] : "???");
505 	}
506 
507 	dev->i2c_scan_running = false;
508 }
509 
510 /*
511  * cx231xx_i2c_register()
512  * register i2c bus
513  */
514 int cx231xx_i2c_register(struct cx231xx_i2c *bus)
515 {
516 	struct cx231xx *dev = bus->dev;
517 
518 	BUG_ON(!dev->cx231xx_send_usb_command);
519 
520 	bus->i2c_adap = cx231xx_adap_template;
521 	bus->i2c_adap.dev.parent = dev->dev;
522 
523 	snprintf(bus->i2c_adap.name, sizeof(bus->i2c_adap.name), "%s-%d", bus->dev->name, bus->nr);
524 
525 	bus->i2c_adap.algo_data = bus;
526 	i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
527 	bus->i2c_rc = i2c_add_adapter(&bus->i2c_adap);
528 
529 	if (0 != bus->i2c_rc)
530 		dev_warn(dev->dev,
531 			 "i2c bus %d register FAILED\n", bus->nr);
532 
533 	return bus->i2c_rc;
534 }
535 
536 /*
537  * cx231xx_i2c_unregister()
538  * unregister i2c_bus
539  */
540 void cx231xx_i2c_unregister(struct cx231xx_i2c *bus)
541 {
542 	if (!bus->i2c_rc)
543 		i2c_del_adapter(&bus->i2c_adap);
544 }
545 
546 /*
547  * cx231xx_i2c_mux_select()
548  * switch i2c master number 1 between port1 and port3
549  */
550 static int cx231xx_i2c_mux_select(struct i2c_mux_core *muxc, u32 chan_id)
551 {
552 	struct cx231xx *dev = i2c_mux_priv(muxc);
553 
554 	return cx231xx_enable_i2c_port_3(dev, chan_id);
555 }
556 
557 int cx231xx_i2c_mux_create(struct cx231xx *dev)
558 {
559 	dev->muxc = i2c_mux_alloc(&dev->i2c_bus[1].i2c_adap, dev->dev, 2, 0, 0,
560 				  cx231xx_i2c_mux_select, NULL);
561 	if (!dev->muxc)
562 		return -ENOMEM;
563 	dev->muxc->priv = dev;
564 	return 0;
565 }
566 
567 int cx231xx_i2c_mux_register(struct cx231xx *dev, int mux_no)
568 {
569 	return i2c_mux_add_adapter(dev->muxc,
570 				   0,
571 				   mux_no /* chan_id */,
572 				   0 /* class */);
573 }
574 
575 void cx231xx_i2c_mux_unregister(struct cx231xx *dev)
576 {
577 	i2c_mux_del_adapters(dev->muxc);
578 }
579 
580 struct i2c_adapter *cx231xx_get_i2c_adap(struct cx231xx *dev, int i2c_port)
581 {
582 	switch (i2c_port) {
583 	case I2C_0:
584 		return &dev->i2c_bus[0].i2c_adap;
585 	case I2C_1:
586 		return &dev->i2c_bus[1].i2c_adap;
587 	case I2C_2:
588 		return &dev->i2c_bus[2].i2c_adap;
589 	case I2C_1_MUX_1:
590 		return dev->muxc->adapter[0];
591 	case I2C_1_MUX_3:
592 		return dev->muxc->adapter[1];
593 	default:
594 		BUG();
595 	}
596 }
597 EXPORT_SYMBOL_GPL(cx231xx_get_i2c_adap);
598