1 /*
2  * cxd2099.c: Driver for the CXD2099AR Common Interface Controller
3  *
4  * Copyright (C) 2010-2013 Digital Devices GmbH
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * version 2 only, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  */
15 
16 #include <linux/slab.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/i2c.h>
20 #include <linux/regmap.h>
21 #include <linux/wait.h>
22 #include <linux/delay.h>
23 #include <linux/mutex.h>
24 #include <linux/io.h>
25 
26 #include "cxd2099.h"
27 
28 static int buffermode;
29 module_param(buffermode, int, 0444);
30 MODULE_PARM_DESC(buffermode, "Enable CXD2099AR buffer mode (default: disabled)");
31 
32 static int read_data(struct dvb_ca_en50221 *ca, int slot, u8 *ebuf, int ecount);
33 
34 struct cxd {
35 	struct dvb_ca_en50221 en;
36 
37 	struct cxd2099_cfg cfg;
38 	struct i2c_client *client;
39 	struct regmap *regmap;
40 
41 	u8     regs[0x23];
42 	u8     lastaddress;
43 	u8     clk_reg_f;
44 	u8     clk_reg_b;
45 	int    mode;
46 	int    ready;
47 	int    dr;
48 	int    write_busy;
49 	int    slot_stat;
50 
51 	u8     amem[1024];
52 	int    amem_read;
53 
54 	int    cammode;
55 	struct mutex lock; /* device access lock */
56 
57 	u8     rbuf[1028];
58 	u8     wbuf[1028];
59 };
60 
61 static int read_block(struct cxd *ci, u8 adr, u8 *data, u16 n)
62 {
63 	int status = 0;
64 
65 	if (ci->lastaddress != adr)
66 		status = regmap_write(ci->regmap, 0, adr);
67 	if (!status) {
68 		ci->lastaddress = adr;
69 
70 		while (n) {
71 			int len = n;
72 
73 			if (ci->cfg.max_i2c && len > ci->cfg.max_i2c)
74 				len = ci->cfg.max_i2c;
75 			status = regmap_raw_read(ci->regmap, 1, data, len);
76 			if (status)
77 				return status;
78 			data += len;
79 			n -= len;
80 		}
81 	}
82 	return status;
83 }
84 
85 static int read_reg(struct cxd *ci, u8 reg, u8 *val)
86 {
87 	return read_block(ci, reg, val, 1);
88 }
89 
90 static int read_pccard(struct cxd *ci, u16 address, u8 *data, u8 n)
91 {
92 	int status;
93 	u8 addr[2] = {address & 0xff, address >> 8};
94 
95 	status = regmap_raw_write(ci->regmap, 2, addr, 2);
96 	if (!status)
97 		status = regmap_raw_read(ci->regmap, 3, data, n);
98 	return status;
99 }
100 
101 static int write_pccard(struct cxd *ci, u16 address, u8 *data, u8 n)
102 {
103 	int status;
104 	u8 addr[2] = {address & 0xff, address >> 8};
105 
106 	status = regmap_raw_write(ci->regmap, 2, addr, 2);
107 	if (!status) {
108 		u8 buf[256];
109 
110 		memcpy(buf, data, n);
111 		status = regmap_raw_write(ci->regmap, 3, buf, n);
112 	}
113 	return status;
114 }
115 
116 static int read_io(struct cxd *ci, u16 address, unsigned int *val)
117 {
118 	int status;
119 	u8 addr[2] = {address & 0xff, address >> 8};
120 
121 	status = regmap_raw_write(ci->regmap, 2, addr, 2);
122 	if (!status)
123 		status = regmap_read(ci->regmap, 3, val);
124 	return status;
125 }
126 
127 static int write_io(struct cxd *ci, u16 address, u8 val)
128 {
129 	int status;
130 	u8 addr[2] = {address & 0xff, address >> 8};
131 
132 	status = regmap_raw_write(ci->regmap, 2, addr, 2);
133 	if (!status)
134 		status = regmap_write(ci->regmap, 3, val);
135 	return status;
136 }
137 
138 static int write_regm(struct cxd *ci, u8 reg, u8 val, u8 mask)
139 {
140 	int status = 0;
141 	unsigned int regval;
142 
143 	if (ci->lastaddress != reg)
144 		status = regmap_write(ci->regmap, 0, reg);
145 	if (!status && reg >= 6 && reg <= 8 && mask != 0xff) {
146 		status = regmap_read(ci->regmap, 1, &regval);
147 		ci->regs[reg] = regval;
148 	}
149 	ci->lastaddress = reg;
150 	ci->regs[reg] = (ci->regs[reg] & (~mask)) | val;
151 	if (!status)
152 		status = regmap_write(ci->regmap, 1, ci->regs[reg]);
153 	if (reg == 0x20)
154 		ci->regs[reg] &= 0x7f;
155 	return status;
156 }
157 
158 static int write_reg(struct cxd *ci, u8 reg, u8 val)
159 {
160 	return write_regm(ci, reg, val, 0xff);
161 }
162 
163 static int write_block(struct cxd *ci, u8 adr, u8 *data, u16 n)
164 {
165 	int status = 0;
166 	u8 *buf = ci->wbuf;
167 
168 	if (ci->lastaddress != adr)
169 		status = regmap_write(ci->regmap, 0, adr);
170 	if (status)
171 		return status;
172 
173 	ci->lastaddress = adr;
174 	while (n) {
175 		int len = n;
176 
177 		if (ci->cfg.max_i2c && (len + 1 > ci->cfg.max_i2c))
178 			len = ci->cfg.max_i2c - 1;
179 		memcpy(buf, data, len);
180 		status = regmap_raw_write(ci->regmap, 1, buf, len);
181 		if (status)
182 			return status;
183 		n -= len;
184 		data += len;
185 	}
186 	return status;
187 }
188 
189 static void set_mode(struct cxd *ci, int mode)
190 {
191 	if (mode == ci->mode)
192 		return;
193 
194 	switch (mode) {
195 	case 0x00: /* IO mem */
196 		write_regm(ci, 0x06, 0x00, 0x07);
197 		break;
198 	case 0x01: /* ATT mem */
199 		write_regm(ci, 0x06, 0x02, 0x07);
200 		break;
201 	default:
202 		break;
203 	}
204 	ci->mode = mode;
205 }
206 
207 static void cam_mode(struct cxd *ci, int mode)
208 {
209 	u8 dummy;
210 
211 	if (mode == ci->cammode)
212 		return;
213 
214 	switch (mode) {
215 	case 0x00:
216 		write_regm(ci, 0x20, 0x80, 0x80);
217 		break;
218 	case 0x01:
219 		if (!ci->en.read_data)
220 			return;
221 		ci->write_busy = 0;
222 		dev_info(&ci->client->dev, "enable cam buffer mode\n");
223 		write_reg(ci, 0x0d, 0x00);
224 		write_reg(ci, 0x0e, 0x01);
225 		write_regm(ci, 0x08, 0x40, 0x40);
226 		read_reg(ci, 0x12, &dummy);
227 		write_regm(ci, 0x08, 0x80, 0x80);
228 		break;
229 	default:
230 		break;
231 	}
232 	ci->cammode = mode;
233 }
234 
235 static int init(struct cxd *ci)
236 {
237 	int status;
238 
239 	mutex_lock(&ci->lock);
240 	ci->mode = -1;
241 	do {
242 		status = write_reg(ci, 0x00, 0x00);
243 		if (status < 0)
244 			break;
245 		status = write_reg(ci, 0x01, 0x00);
246 		if (status < 0)
247 			break;
248 		status = write_reg(ci, 0x02, 0x10);
249 		if (status < 0)
250 			break;
251 		status = write_reg(ci, 0x03, 0x00);
252 		if (status < 0)
253 			break;
254 		status = write_reg(ci, 0x05, 0xFF);
255 		if (status < 0)
256 			break;
257 		status = write_reg(ci, 0x06, 0x1F);
258 		if (status < 0)
259 			break;
260 		status = write_reg(ci, 0x07, 0x1F);
261 		if (status < 0)
262 			break;
263 		status = write_reg(ci, 0x08, 0x28);
264 		if (status < 0)
265 			break;
266 		status = write_reg(ci, 0x14, 0x20);
267 		if (status < 0)
268 			break;
269 
270 		/* TOSTRT = 8, Mode B (gated clock), falling Edge,
271 		 * Serial, POL=HIGH, MSB
272 		 */
273 		status = write_reg(ci, 0x0A, 0xA7);
274 		if (status < 0)
275 			break;
276 
277 		status = write_reg(ci, 0x0B, 0x33);
278 		if (status < 0)
279 			break;
280 		status = write_reg(ci, 0x0C, 0x33);
281 		if (status < 0)
282 			break;
283 
284 		status = write_regm(ci, 0x14, 0x00, 0x0F);
285 		if (status < 0)
286 			break;
287 		status = write_reg(ci, 0x15, ci->clk_reg_b);
288 		if (status < 0)
289 			break;
290 		status = write_regm(ci, 0x16, 0x00, 0x0F);
291 		if (status < 0)
292 			break;
293 		status = write_reg(ci, 0x17, ci->clk_reg_f);
294 		if (status < 0)
295 			break;
296 
297 		if (ci->cfg.clock_mode == 2) {
298 			/* bitrate*2^13/ 72000 */
299 			u32 reg = ((ci->cfg.bitrate << 13) + 71999) / 72000;
300 
301 			if (ci->cfg.polarity) {
302 				status = write_reg(ci, 0x09, 0x6f);
303 				if (status < 0)
304 					break;
305 			} else {
306 				status = write_reg(ci, 0x09, 0x6d);
307 				if (status < 0)
308 					break;
309 			}
310 			status = write_reg(ci, 0x20, 0x08);
311 			if (status < 0)
312 				break;
313 			status = write_reg(ci, 0x21, (reg >> 8) & 0xff);
314 			if (status < 0)
315 				break;
316 			status = write_reg(ci, 0x22, reg & 0xff);
317 			if (status < 0)
318 				break;
319 		} else if (ci->cfg.clock_mode == 1) {
320 			if (ci->cfg.polarity) {
321 				status = write_reg(ci, 0x09, 0x6f); /* D */
322 				if (status < 0)
323 					break;
324 			} else {
325 				status = write_reg(ci, 0x09, 0x6d);
326 				if (status < 0)
327 					break;
328 			}
329 			status = write_reg(ci, 0x20, 0x68);
330 			if (status < 0)
331 				break;
332 			status = write_reg(ci, 0x21, 0x00);
333 			if (status < 0)
334 				break;
335 			status = write_reg(ci, 0x22, 0x02);
336 			if (status < 0)
337 				break;
338 		} else {
339 			if (ci->cfg.polarity) {
340 				status = write_reg(ci, 0x09, 0x4f); /* C */
341 				if (status < 0)
342 					break;
343 			} else {
344 				status = write_reg(ci, 0x09, 0x4d);
345 				if (status < 0)
346 					break;
347 			}
348 			status = write_reg(ci, 0x20, 0x28);
349 			if (status < 0)
350 				break;
351 			status = write_reg(ci, 0x21, 0x00);
352 			if (status < 0)
353 				break;
354 			status = write_reg(ci, 0x22, 0x07);
355 			if (status < 0)
356 				break;
357 		}
358 
359 		status = write_regm(ci, 0x20, 0x80, 0x80);
360 		if (status < 0)
361 			break;
362 		status = write_regm(ci, 0x03, 0x02, 0x02);
363 		if (status < 0)
364 			break;
365 		status = write_reg(ci, 0x01, 0x04);
366 		if (status < 0)
367 			break;
368 		status = write_reg(ci, 0x00, 0x31);
369 		if (status < 0)
370 			break;
371 
372 		/* Put TS in bypass */
373 		status = write_regm(ci, 0x09, 0x08, 0x08);
374 		if (status < 0)
375 			break;
376 		ci->cammode = -1;
377 		cam_mode(ci, 0);
378 	} while (0);
379 	mutex_unlock(&ci->lock);
380 
381 	return 0;
382 }
383 
384 static int read_attribute_mem(struct dvb_ca_en50221 *ca,
385 			      int slot, int address)
386 {
387 	struct cxd *ci = ca->data;
388 	u8 val;
389 
390 	mutex_lock(&ci->lock);
391 	set_mode(ci, 1);
392 	read_pccard(ci, address, &val, 1);
393 	mutex_unlock(&ci->lock);
394 	return val;
395 }
396 
397 static int write_attribute_mem(struct dvb_ca_en50221 *ca, int slot,
398 			       int address, u8 value)
399 {
400 	struct cxd *ci = ca->data;
401 
402 	mutex_lock(&ci->lock);
403 	set_mode(ci, 1);
404 	write_pccard(ci, address, &value, 1);
405 	mutex_unlock(&ci->lock);
406 	return 0;
407 }
408 
409 static int read_cam_control(struct dvb_ca_en50221 *ca,
410 			    int slot, u8 address)
411 {
412 	struct cxd *ci = ca->data;
413 	unsigned int val;
414 
415 	mutex_lock(&ci->lock);
416 	set_mode(ci, 0);
417 	read_io(ci, address, &val);
418 	mutex_unlock(&ci->lock);
419 	return val;
420 }
421 
422 static int write_cam_control(struct dvb_ca_en50221 *ca, int slot,
423 			     u8 address, u8 value)
424 {
425 	struct cxd *ci = ca->data;
426 
427 	mutex_lock(&ci->lock);
428 	set_mode(ci, 0);
429 	write_io(ci, address, value);
430 	mutex_unlock(&ci->lock);
431 	return 0;
432 }
433 
434 static int slot_reset(struct dvb_ca_en50221 *ca, int slot)
435 {
436 	struct cxd *ci = ca->data;
437 
438 	if (ci->cammode)
439 		read_data(ca, slot, ci->rbuf, 0);
440 
441 	mutex_lock(&ci->lock);
442 	cam_mode(ci, 0);
443 	write_reg(ci, 0x00, 0x21);
444 	write_reg(ci, 0x06, 0x1F);
445 	write_reg(ci, 0x00, 0x31);
446 	write_regm(ci, 0x20, 0x80, 0x80);
447 	write_reg(ci, 0x03, 0x02);
448 	ci->ready = 0;
449 	ci->mode = -1;
450 	{
451 		int i;
452 
453 		for (i = 0; i < 100; i++) {
454 			usleep_range(10000, 11000);
455 			if (ci->ready)
456 				break;
457 		}
458 	}
459 	mutex_unlock(&ci->lock);
460 	return 0;
461 }
462 
463 static int slot_shutdown(struct dvb_ca_en50221 *ca, int slot)
464 {
465 	struct cxd *ci = ca->data;
466 
467 	dev_dbg(&ci->client->dev, "%s\n", __func__);
468 	if (ci->cammode)
469 		read_data(ca, slot, ci->rbuf, 0);
470 	mutex_lock(&ci->lock);
471 	write_reg(ci, 0x00, 0x21);
472 	write_reg(ci, 0x06, 0x1F);
473 	msleep(300);
474 
475 	write_regm(ci, 0x09, 0x08, 0x08);
476 	write_regm(ci, 0x20, 0x80, 0x80); /* Reset CAM Mode */
477 	write_regm(ci, 0x06, 0x07, 0x07); /* Clear IO Mode */
478 
479 	ci->mode = -1;
480 	ci->write_busy = 0;
481 	mutex_unlock(&ci->lock);
482 	return 0;
483 }
484 
485 static int slot_ts_enable(struct dvb_ca_en50221 *ca, int slot)
486 {
487 	struct cxd *ci = ca->data;
488 
489 	mutex_lock(&ci->lock);
490 	write_regm(ci, 0x09, 0x00, 0x08);
491 	set_mode(ci, 0);
492 	cam_mode(ci, 1);
493 	mutex_unlock(&ci->lock);
494 	return 0;
495 }
496 
497 static int campoll(struct cxd *ci)
498 {
499 	u8 istat;
500 
501 	read_reg(ci, 0x04, &istat);
502 	if (!istat)
503 		return 0;
504 	write_reg(ci, 0x05, istat);
505 
506 	if (istat & 0x40)
507 		ci->dr = 1;
508 	if (istat & 0x20)
509 		ci->write_busy = 0;
510 
511 	if (istat & 2) {
512 		u8 slotstat;
513 
514 		read_reg(ci, 0x01, &slotstat);
515 		if (!(2 & slotstat)) {
516 			if (!ci->slot_stat) {
517 				ci->slot_stat |=
518 					      DVB_CA_EN50221_POLL_CAM_PRESENT;
519 				write_regm(ci, 0x03, 0x08, 0x08);
520 			}
521 
522 		} else {
523 			if (ci->slot_stat) {
524 				ci->slot_stat = 0;
525 				write_regm(ci, 0x03, 0x00, 0x08);
526 				dev_info(&ci->client->dev, "NO CAM\n");
527 				ci->ready = 0;
528 			}
529 		}
530 		if ((istat & 8) &&
531 		    ci->slot_stat == DVB_CA_EN50221_POLL_CAM_PRESENT) {
532 			ci->ready = 1;
533 			ci->slot_stat |= DVB_CA_EN50221_POLL_CAM_READY;
534 		}
535 	}
536 	return 0;
537 }
538 
539 static int poll_slot_status(struct dvb_ca_en50221 *ca, int slot, int open)
540 {
541 	struct cxd *ci = ca->data;
542 	u8 slotstat;
543 
544 	mutex_lock(&ci->lock);
545 	campoll(ci);
546 	read_reg(ci, 0x01, &slotstat);
547 	mutex_unlock(&ci->lock);
548 
549 	return ci->slot_stat;
550 }
551 
552 static int read_data(struct dvb_ca_en50221 *ca, int slot, u8 *ebuf, int ecount)
553 {
554 	struct cxd *ci = ca->data;
555 	u8 msb, lsb;
556 	u16 len;
557 
558 	mutex_lock(&ci->lock);
559 	campoll(ci);
560 	mutex_unlock(&ci->lock);
561 
562 	if (!ci->dr)
563 		return 0;
564 
565 	mutex_lock(&ci->lock);
566 	read_reg(ci, 0x0f, &msb);
567 	read_reg(ci, 0x10, &lsb);
568 	len = ((u16)msb << 8) | lsb;
569 	if (len > ecount || len < 2) {
570 		/* read it anyway or cxd may hang */
571 		read_block(ci, 0x12, ci->rbuf, len);
572 		mutex_unlock(&ci->lock);
573 		return -EIO;
574 	}
575 	read_block(ci, 0x12, ebuf, len);
576 	ci->dr = 0;
577 	mutex_unlock(&ci->lock);
578 	return len;
579 }
580 
581 static int write_data(struct dvb_ca_en50221 *ca, int slot, u8 *ebuf, int ecount)
582 {
583 	struct cxd *ci = ca->data;
584 
585 	if (ci->write_busy)
586 		return -EAGAIN;
587 	mutex_lock(&ci->lock);
588 	write_reg(ci, 0x0d, ecount >> 8);
589 	write_reg(ci, 0x0e, ecount & 0xff);
590 	write_block(ci, 0x11, ebuf, ecount);
591 	ci->write_busy = 1;
592 	mutex_unlock(&ci->lock);
593 	return ecount;
594 }
595 
596 static struct dvb_ca_en50221 en_templ = {
597 	.read_attribute_mem  = read_attribute_mem,
598 	.write_attribute_mem = write_attribute_mem,
599 	.read_cam_control    = read_cam_control,
600 	.write_cam_control   = write_cam_control,
601 	.slot_reset          = slot_reset,
602 	.slot_shutdown       = slot_shutdown,
603 	.slot_ts_enable      = slot_ts_enable,
604 	.poll_slot_status    = poll_slot_status,
605 	.read_data           = read_data,
606 	.write_data          = write_data,
607 };
608 
609 static int cxd2099_probe(struct i2c_client *client,
610 			 const struct i2c_device_id *id)
611 {
612 	struct cxd *ci;
613 	struct cxd2099_cfg *cfg = client->dev.platform_data;
614 	static const struct regmap_config rm_cfg = {
615 		.reg_bits = 8,
616 		.val_bits = 8,
617 	};
618 	unsigned int val;
619 	int ret;
620 
621 	ci = kzalloc(sizeof(*ci), GFP_KERNEL);
622 	if (!ci) {
623 		ret = -ENOMEM;
624 		goto err;
625 	}
626 
627 	ci->client = client;
628 	memcpy(&ci->cfg, cfg, sizeof(ci->cfg));
629 
630 	ci->regmap = regmap_init_i2c(client, &rm_cfg);
631 	if (IS_ERR(ci->regmap)) {
632 		ret = PTR_ERR(ci->regmap);
633 		goto err_kfree;
634 	}
635 
636 	ret = regmap_read(ci->regmap, 0x00, &val);
637 	if (ret < 0) {
638 		dev_info(&client->dev, "No CXD2099AR detected at 0x%02x\n",
639 			 client->addr);
640 		goto err_rmexit;
641 	}
642 
643 	mutex_init(&ci->lock);
644 	ci->lastaddress = 0xff;
645 	ci->clk_reg_b = 0x4a;
646 	ci->clk_reg_f = 0x1b;
647 
648 	ci->en = en_templ;
649 	ci->en.data = ci;
650 	init(ci);
651 	dev_info(&client->dev, "Attached CXD2099AR at 0x%02x\n", client->addr);
652 
653 	*cfg->en = &ci->en;
654 
655 	if (!buffermode) {
656 		ci->en.read_data = NULL;
657 		ci->en.write_data = NULL;
658 	} else {
659 		dev_info(&client->dev, "Using CXD2099AR buffer mode");
660 	}
661 
662 	i2c_set_clientdata(client, ci);
663 
664 	return 0;
665 
666 err_rmexit:
667 	regmap_exit(ci->regmap);
668 err_kfree:
669 	kfree(ci);
670 err:
671 
672 	return ret;
673 }
674 
675 static int cxd2099_remove(struct i2c_client *client)
676 {
677 	struct cxd *ci = i2c_get_clientdata(client);
678 
679 	regmap_exit(ci->regmap);
680 	kfree(ci);
681 
682 	return 0;
683 }
684 
685 static const struct i2c_device_id cxd2099_id[] = {
686 	{"cxd2099", 0},
687 	{}
688 };
689 MODULE_DEVICE_TABLE(i2c, cxd2099_id);
690 
691 static struct i2c_driver cxd2099_driver = {
692 	.driver = {
693 		.name	= "cxd2099",
694 	},
695 	.probe		= cxd2099_probe,
696 	.remove		= cxd2099_remove,
697 	.id_table	= cxd2099_id,
698 };
699 
700 module_i2c_driver(cxd2099_driver);
701 
702 MODULE_DESCRIPTION("CXD2099AR Common Interface controller driver");
703 MODULE_AUTHOR("Ralph Metzler");
704 MODULE_LICENSE("GPL");
705