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1 /*
2  *
3  * device driver for philips saa7134 based TV cards
4  * i2c interface support
5  *
6  * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]
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 <linux/init.h>
24 #include <linux/list.h>
25 #include <linux/module.h>
26 #include <linux/kernel.h>
27 #include <linux/slab.h>
28 #include <linux/delay.h>
29 
30 #include "saa7134-reg.h"
31 #include "saa7134.h"
32 #include <media/v4l2-common.h>
33 
34 /* ----------------------------------------------------------- */
35 
36 static unsigned int i2c_debug;
37 module_param(i2c_debug, int, 0644);
38 MODULE_PARM_DESC(i2c_debug,"enable debug messages [i2c]");
39 
40 static unsigned int i2c_scan;
41 module_param(i2c_scan, int, 0444);
42 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");
43 
44 #define d1printk if (1 == i2c_debug) printk
45 #define d2printk if (2 == i2c_debug) printk
46 
47 #define I2C_WAIT_DELAY  32
48 #define I2C_WAIT_RETRY  16
49 
50 /* ----------------------------------------------------------- */
51 
52 static char *str_i2c_status[] = {
53 	"IDLE", "DONE_STOP", "BUSY", "TO_SCL", "TO_ARB", "DONE_WRITE",
54 	"DONE_READ", "DONE_WRITE_TO", "DONE_READ_TO", "NO_DEVICE",
55 	"NO_ACKN", "BUS_ERR", "ARB_LOST", "SEQ_ERR", "ST_ERR", "SW_ERR"
56 };
57 
58 enum i2c_status {
59 	IDLE          = 0,  // no I2C command pending
60 	DONE_STOP     = 1,  // I2C command done and STOP executed
61 	BUSY          = 2,  // executing I2C command
62 	TO_SCL        = 3,  // executing I2C command, time out on clock stretching
63 	TO_ARB        = 4,  // time out on arbitration trial, still trying
64 	DONE_WRITE    = 5,  // I2C command done and awaiting next write command
65 	DONE_READ     = 6,  // I2C command done and awaiting next read command
66 	DONE_WRITE_TO = 7,  // see 5, and time out on status echo
67 	DONE_READ_TO  = 8,  // see 6, and time out on status echo
68 	NO_DEVICE     = 9,  // no acknowledge on device slave address
69 	NO_ACKN       = 10, // no acknowledge after data byte transfer
70 	BUS_ERR       = 11, // bus error
71 	ARB_LOST      = 12, // arbitration lost during transfer
72 	SEQ_ERR       = 13, // erroneous programming sequence
73 	ST_ERR        = 14, // wrong status echoing
74 	SW_ERR        = 15  // software error
75 };
76 
77 static char *str_i2c_attr[] = {
78 	"NOP", "STOP", "CONTINUE", "START"
79 };
80 
81 enum i2c_attr {
82 	NOP           = 0,  // no operation on I2C bus
83 	STOP          = 1,  // stop condition, no associated byte transfer
84 	CONTINUE      = 2,  // continue with byte transfer
85 	START         = 3   // start condition with byte transfer
86 };
87 
i2c_get_status(struct saa7134_dev * dev)88 static inline enum i2c_status i2c_get_status(struct saa7134_dev *dev)
89 {
90 	enum i2c_status status;
91 
92 	status = saa_readb(SAA7134_I2C_ATTR_STATUS) & 0x0f;
93 	d2printk(KERN_DEBUG "%s: i2c stat <= %s\n",dev->name,
94 		 str_i2c_status[status]);
95 	return status;
96 }
97 
i2c_set_status(struct saa7134_dev * dev,enum i2c_status status)98 static inline void i2c_set_status(struct saa7134_dev *dev,
99 				  enum i2c_status status)
100 {
101 	d2printk(KERN_DEBUG "%s: i2c stat => %s\n",dev->name,
102 		 str_i2c_status[status]);
103 	saa_andorb(SAA7134_I2C_ATTR_STATUS,0x0f,status);
104 }
105 
i2c_set_attr(struct saa7134_dev * dev,enum i2c_attr attr)106 static inline void i2c_set_attr(struct saa7134_dev *dev, enum i2c_attr attr)
107 {
108 	d2printk(KERN_DEBUG "%s: i2c attr => %s\n",dev->name,
109 		 str_i2c_attr[attr]);
110 	saa_andorb(SAA7134_I2C_ATTR_STATUS,0xc0,attr << 6);
111 }
112 
i2c_is_error(enum i2c_status status)113 static inline int i2c_is_error(enum i2c_status status)
114 {
115 	switch (status) {
116 	case NO_DEVICE:
117 	case NO_ACKN:
118 	case BUS_ERR:
119 	case ARB_LOST:
120 	case SEQ_ERR:
121 	case ST_ERR:
122 		return true;
123 	default:
124 		return false;
125 	}
126 }
127 
i2c_is_idle(enum i2c_status status)128 static inline int i2c_is_idle(enum i2c_status status)
129 {
130 	switch (status) {
131 	case IDLE:
132 	case DONE_STOP:
133 		return true;
134 	default:
135 		return false;
136 	}
137 }
138 
i2c_is_busy(enum i2c_status status)139 static inline int i2c_is_busy(enum i2c_status status)
140 {
141 	switch (status) {
142 	case BUSY:
143 	case TO_SCL:
144 	case TO_ARB:
145 		return true;
146 	default:
147 		return false;
148 	}
149 }
150 
i2c_is_busy_wait(struct saa7134_dev * dev)151 static int i2c_is_busy_wait(struct saa7134_dev *dev)
152 {
153 	enum i2c_status status;
154 	int count;
155 
156 	for (count = 0; count < I2C_WAIT_RETRY; count++) {
157 		status = i2c_get_status(dev);
158 		if (!i2c_is_busy(status))
159 			break;
160 		saa_wait(I2C_WAIT_DELAY);
161 	}
162 	if (I2C_WAIT_RETRY == count)
163 		return false;
164 	return true;
165 }
166 
i2c_reset(struct saa7134_dev * dev)167 static int i2c_reset(struct saa7134_dev *dev)
168 {
169 	enum i2c_status status;
170 	int count;
171 
172 	d2printk(KERN_DEBUG "%s: i2c reset\n",dev->name);
173 	status = i2c_get_status(dev);
174 	if (!i2c_is_error(status))
175 		return true;
176 	i2c_set_status(dev,status);
177 
178 	for (count = 0; count < I2C_WAIT_RETRY; count++) {
179 		status = i2c_get_status(dev);
180 		if (!i2c_is_error(status))
181 			break;
182 		udelay(I2C_WAIT_DELAY);
183 	}
184 	if (I2C_WAIT_RETRY == count)
185 		return false;
186 
187 	if (!i2c_is_idle(status))
188 		return false;
189 
190 	i2c_set_attr(dev,NOP);
191 	return true;
192 }
193 
i2c_send_byte(struct saa7134_dev * dev,enum i2c_attr attr,unsigned char data)194 static inline int i2c_send_byte(struct saa7134_dev *dev,
195 				enum i2c_attr attr,
196 				unsigned char data)
197 {
198 	enum i2c_status status;
199 	__u32 dword;
200 
201 	/* have to write both attr + data in one 32bit word */
202 	dword  = saa_readl(SAA7134_I2C_ATTR_STATUS >> 2);
203 	dword &= 0x0f;
204 	dword |= (attr << 6);
205 	dword |= ((__u32)data << 8);
206 	dword |= 0x00 << 16;  /* 100 kHz */
207 //	dword |= 0x40 << 16;  /* 400 kHz */
208 	dword |= 0xf0 << 24;
209 	saa_writel(SAA7134_I2C_ATTR_STATUS >> 2, dword);
210 	d2printk(KERN_DEBUG "%s: i2c data => 0x%x\n",dev->name,data);
211 
212 	if (!i2c_is_busy_wait(dev))
213 		return -EIO;
214 	status = i2c_get_status(dev);
215 	if (i2c_is_error(status))
216 		return -EIO;
217 	return 0;
218 }
219 
i2c_recv_byte(struct saa7134_dev * dev)220 static inline int i2c_recv_byte(struct saa7134_dev *dev)
221 {
222 	enum i2c_status status;
223 	unsigned char data;
224 
225 	i2c_set_attr(dev,CONTINUE);
226 	if (!i2c_is_busy_wait(dev))
227 		return -EIO;
228 	status = i2c_get_status(dev);
229 	if (i2c_is_error(status))
230 		return -EIO;
231 	data = saa_readb(SAA7134_I2C_DATA);
232 	d2printk(KERN_DEBUG "%s: i2c data <= 0x%x\n",dev->name,data);
233 	return data;
234 }
235 
saa7134_i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg * msgs,int num)236 static int saa7134_i2c_xfer(struct i2c_adapter *i2c_adap,
237 			    struct i2c_msg *msgs, int num)
238 {
239 	struct saa7134_dev *dev = i2c_adap->algo_data;
240 	enum i2c_status status;
241 	unsigned char data;
242 	int addr,rc,i,byte;
243 
244 	status = i2c_get_status(dev);
245 	if (!i2c_is_idle(status))
246 		if (!i2c_reset(dev))
247 			return -EIO;
248 
249 	d2printk("start xfer\n");
250 	d1printk(KERN_DEBUG "%s: i2c xfer:",dev->name);
251 	for (i = 0; i < num; i++) {
252 		if (!(msgs[i].flags & I2C_M_NOSTART) || 0 == i) {
253 			/* send address */
254 			d2printk("send address\n");
255 			addr  = msgs[i].addr << 1;
256 			if (msgs[i].flags & I2C_M_RD)
257 				addr |= 1;
258 			if (i > 0 && msgs[i].flags & I2C_M_RD) {
259 				/* workaround for a saa7134 i2c bug
260 				 * needed to talk to the mt352 demux
261 				 * thanks to pinnacle for the hint */
262 				int quirk = 0xfd;
263 				d1printk(" [%02x quirk]",quirk);
264 				i2c_send_byte(dev,START,quirk);
265 				i2c_recv_byte(dev);
266 			}
267 			d1printk(" < %02x", addr);
268 			rc = i2c_send_byte(dev,START,addr);
269 			if (rc < 0)
270 				 goto err;
271 		}
272 		if (msgs[i].flags & I2C_M_RD) {
273 			/* read bytes */
274 			d2printk("read bytes\n");
275 			for (byte = 0; byte < msgs[i].len; byte++) {
276 				d1printk(" =");
277 				rc = i2c_recv_byte(dev);
278 				if (rc < 0)
279 					goto err;
280 				d1printk("%02x", rc);
281 				msgs[i].buf[byte] = rc;
282 			}
283 		} else {
284 			/* write bytes */
285 			d2printk("write bytes\n");
286 			for (byte = 0; byte < msgs[i].len; byte++) {
287 				data = msgs[i].buf[byte];
288 				d1printk(" %02x", data);
289 				rc = i2c_send_byte(dev,CONTINUE,data);
290 				if (rc < 0)
291 					goto err;
292 			}
293 		}
294 	}
295 	d2printk("xfer done\n");
296 	d1printk(" >");
297 	i2c_set_attr(dev,STOP);
298 	rc = -EIO;
299 	if (!i2c_is_busy_wait(dev))
300 		goto err;
301 	status = i2c_get_status(dev);
302 	if (i2c_is_error(status))
303 		goto err;
304 	/* ensure that the bus is idle for at least one bit slot */
305 	msleep(1);
306 
307 	d1printk("\n");
308 	return num;
309  err:
310 	if (1 == i2c_debug) {
311 		status = i2c_get_status(dev);
312 		printk(" ERROR: %s\n",str_i2c_status[status]);
313 	}
314 	return rc;
315 }
316 
317 /* ----------------------------------------------------------- */
318 
functionality(struct i2c_adapter * adap)319 static u32 functionality(struct i2c_adapter *adap)
320 {
321 	return I2C_FUNC_SMBUS_EMUL;
322 }
323 
attach_inform(struct i2c_client * client)324 static int attach_inform(struct i2c_client *client)
325 {
326 	struct saa7134_dev *dev = client->adapter->algo_data;
327 
328 	d1printk( "%s i2c attach [addr=0x%x,client=%s]\n",
329 		client->driver->driver.name, client->addr, client->name);
330 	if (client->addr == 0x20 && client->driver && client->driver->command)
331 		dev->mpeg_i2c_client = client;
332 
333 	/* Am I an i2c remote control? */
334 
335 	switch (client->addr) {
336 		case 0x7a:
337 		case 0x47:
338 		case 0x71:
339 		case 0x2d:
340 		case 0x30:
341 		{
342 			struct IR_i2c *ir = i2c_get_clientdata(client);
343 			d1printk("%s i2c IR detected (%s).\n",
344 				 client->driver->driver.name, ir->phys);
345 			saa7134_set_i2c_ir(dev,ir);
346 			break;
347 		}
348 	}
349 
350 	return 0;
351 }
352 
353 static struct i2c_algorithm saa7134_algo = {
354 	.master_xfer   = saa7134_i2c_xfer,
355 	.functionality = functionality,
356 };
357 
358 static struct i2c_adapter saa7134_adap_template = {
359 	.owner         = THIS_MODULE,
360 	.class         = I2C_CLASS_TV_ANALOG,
361 	.name          = "saa7134",
362 	.id            = I2C_HW_SAA7134,
363 	.algo          = &saa7134_algo,
364 	.client_register = attach_inform,
365 };
366 
367 static struct i2c_client saa7134_client_template = {
368 	.name	= "saa7134 internal",
369 };
370 
371 /* ----------------------------------------------------------- */
372 
373 static int
saa7134_i2c_eeprom(struct saa7134_dev * dev,unsigned char * eedata,int len)374 saa7134_i2c_eeprom(struct saa7134_dev *dev, unsigned char *eedata, int len)
375 {
376 	unsigned char buf;
377 	int i,err;
378 
379 	dev->i2c_client.addr = 0xa0 >> 1;
380 	buf = 0;
381 	if (1 != (err = i2c_master_send(&dev->i2c_client,&buf,1))) {
382 		printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n",
383 		       dev->name,err);
384 		return -1;
385 	}
386 	if (len != (err = i2c_master_recv(&dev->i2c_client,eedata,len))) {
387 		printk(KERN_WARNING "%s: i2c eeprom read error (err=%d)\n",
388 		       dev->name,err);
389 		return -1;
390 	}
391 	for (i = 0; i < len; i++) {
392 		if (0 == (i % 16))
393 			printk(KERN_INFO "%s: i2c eeprom %02x:",dev->name,i);
394 		printk(" %02x",eedata[i]);
395 		if (15 == (i % 16))
396 			printk("\n");
397 	}
398 	return 0;
399 }
400 
401 static char *i2c_devs[128] = {
402 	[ 0x20      ] = "mpeg encoder (saa6752hs)",
403 	[ 0xa0 >> 1 ] = "eeprom",
404 	[ 0xc0 >> 1 ] = "tuner (analog)",
405 	[ 0x86 >> 1 ] = "tda9887",
406 	[ 0x5a >> 1 ] = "remote control",
407 };
408 
do_i2c_scan(char * name,struct i2c_client * c)409 static void do_i2c_scan(char *name, struct i2c_client *c)
410 {
411 	unsigned char buf;
412 	int i,rc;
413 
414 	for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
415 		c->addr = i;
416 		rc = i2c_master_recv(c,&buf,0);
417 		if (rc < 0)
418 			continue;
419 		printk("%s: i2c scan: found device @ 0x%x  [%s]\n",
420 		       name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
421 	}
422 }
423 
saa7134_i2c_call_clients(struct saa7134_dev * dev,unsigned int cmd,void * arg)424 void saa7134_i2c_call_clients(struct saa7134_dev *dev,
425 			      unsigned int cmd, void *arg)
426 {
427 	BUG_ON(NULL == dev->i2c_adap.algo_data);
428 	i2c_clients_command(&dev->i2c_adap, cmd, arg);
429 }
430 
saa7134_i2c_call_saa6752(struct saa7134_dev * dev,unsigned int cmd,void * arg)431 int saa7134_i2c_call_saa6752(struct saa7134_dev *dev,
432 					      unsigned int cmd, void *arg)
433 {
434 	if (dev->mpeg_i2c_client == NULL)
435 		return -EINVAL;
436 	return dev->mpeg_i2c_client->driver->command(dev->mpeg_i2c_client,
437 								cmd, arg);
438 }
439 EXPORT_SYMBOL_GPL(saa7134_i2c_call_saa6752);
440 
saa7134_i2c_register(struct saa7134_dev * dev)441 int saa7134_i2c_register(struct saa7134_dev *dev)
442 {
443 	dev->i2c_adap = saa7134_adap_template;
444 	dev->i2c_adap.dev.parent = &dev->pci->dev;
445 	strcpy(dev->i2c_adap.name,dev->name);
446 	dev->i2c_adap.algo_data = dev;
447 	i2c_add_adapter(&dev->i2c_adap);
448 
449 	dev->i2c_client = saa7134_client_template;
450 	dev->i2c_client.adapter = &dev->i2c_adap;
451 
452 	saa7134_i2c_eeprom(dev,dev->eedata,sizeof(dev->eedata));
453 	if (i2c_scan)
454 		do_i2c_scan(dev->name,&dev->i2c_client);
455 	return 0;
456 }
457 
saa7134_i2c_unregister(struct saa7134_dev * dev)458 int saa7134_i2c_unregister(struct saa7134_dev *dev)
459 {
460 	i2c_del_adapter(&dev->i2c_adap);
461 	return 0;
462 }
463 
464 /* ----------------------------------------------------------- */
465 /*
466  * Local variables:
467  * c-basic-offset: 8
468  * End:
469  */
470