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
34static unsigned int i2c_scan;
35module_param(i2c_scan, int, 0444);
36MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
37
38static unsigned int i2c_debug;
39module_param(i2c_debug, int, 0644);
40MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
41
42#define dprintk1(lvl, fmt, args...)			\
43do {							\
44	if (i2c_debug >= lvl) {				\
45		printk(fmt, ##args);			\
46		}					\
47} while (0)
48
49#define dprintk2(lvl, fmt, args...)			\
50do {							\
51	if (i2c_debug >= lvl) {				\
52		printk(KERN_DEBUG "%s at %s: " fmt,	\
53		       dev->name, __func__ , ##args);	\
54      } 						\
55} while (0)
56
57static 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
64static 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 */
84static 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 */
195static 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 */
281static 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 */
345static 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 */
372static 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;
441err:
442	dprintk2(2, " ERROR: %i\n", rc);
443	mutex_unlock(&dev->i2c_lock);
444	return rc;
445}
446
447/* ----------------------------------------------------------- */
448
449/*
450 * functionality()
451 */
452static u32 functionality(struct i2c_adapter *adap)
453{
454	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
455}
456
457static struct i2c_algorithm cx231xx_algo = {
458	.master_xfer = cx231xx_i2c_xfer,
459	.functionality = functionality,
460};
461
462static 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 */
474static 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 */
490void 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 */
524int 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 */
550int 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 */
560static 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
568int 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
590void 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
596struct 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}
613EXPORT_SYMBOL_GPL(cx231xx_get_i2c_adap);
614