summaryrefslogtreecommitdiff
path: root/drivers/media/pci/bt8xx/bttv-i2c.c
blob: 15ff7f9d8373822fccd33e6cb842d29d2f527f90 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
/*

    bttv-i2c.c  --  all the i2c code is here

    bttv - Bt848 frame grabber driver

    Copyright (C) 1996,97,98 Ralph  Metzler (rjkm@thp.uni-koeln.de)
			   & Marcus Metzler (mocm@thp.uni-koeln.de)
    (c) 1999-2003 Gerd Knorr <kraxel@bytesex.org>

    (c) 2005 Mauro Carvalho Chehab <mchehab@kernel.org>
	- Multituner support and i2c address binding

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>

#include "bttvp.h"
#include <media/v4l2-common.h>
#include <linux/jiffies.h>
#include <asm/io.h>

static int i2c_debug;
static int i2c_hw;
static int i2c_scan;
module_param(i2c_debug, int, 0644);
MODULE_PARM_DESC(i2c_debug, "configure i2c debug level");
module_param(i2c_hw,    int, 0444);
MODULE_PARM_DESC(i2c_hw, "force use of hardware i2c support, instead of software bitbang");
module_param(i2c_scan,  int, 0444);
MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");

static unsigned int i2c_udelay = 5;
module_param(i2c_udelay, int, 0444);
MODULE_PARM_DESC(i2c_udelay, "soft i2c delay at insmod time, in usecs (should be 5 or higher). Lower value means higher bus speed.");

/* ----------------------------------------------------------------------- */
/* I2C functions - bitbanging adapter (software i2c)                       */

static void bttv_bit_setscl(void *data, int state)
{
	struct bttv *btv = (struct bttv*)data;

	if (state)
		btv->i2c_state |= 0x02;
	else
		btv->i2c_state &= ~0x02;
	btwrite(btv->i2c_state, BT848_I2C);
	btread(BT848_I2C);
}

static void bttv_bit_setsda(void *data, int state)
{
	struct bttv *btv = (struct bttv*)data;

	if (state)
		btv->i2c_state |= 0x01;
	else
		btv->i2c_state &= ~0x01;
	btwrite(btv->i2c_state, BT848_I2C);
	btread(BT848_I2C);
}

static int bttv_bit_getscl(void *data)
{
	struct bttv *btv = (struct bttv*)data;
	int state;

	state = btread(BT848_I2C) & 0x02 ? 1 : 0;
	return state;
}

static int bttv_bit_getsda(void *data)
{
	struct bttv *btv = (struct bttv*)data;
	int state;

	state = btread(BT848_I2C) & 0x01;
	return state;
}

static const struct i2c_algo_bit_data bttv_i2c_algo_bit_template = {
	.setsda  = bttv_bit_setsda,
	.setscl  = bttv_bit_setscl,
	.getsda  = bttv_bit_getsda,
	.getscl  = bttv_bit_getscl,
	.udelay  = 16,
	.timeout = 200,
};

/* ----------------------------------------------------------------------- */
/* I2C functions - hardware i2c                                            */

static u32 functionality(struct i2c_adapter *adap)
{
	return I2C_FUNC_SMBUS_EMUL;
}

static int
bttv_i2c_wait_done(struct bttv *btv)
{
	int rc = 0;

	/* timeout */
	if (wait_event_interruptible_timeout(btv->i2c_queue,
	    btv->i2c_done, msecs_to_jiffies(85)) == -ERESTARTSYS)
		rc = -EIO;

	if (btv->i2c_done & BT848_INT_RACK)
		rc = 1;
	btv->i2c_done = 0;
	return rc;
}

#define I2C_HW (BT878_I2C_MODE  | BT848_I2C_SYNC |\
		BT848_I2C_SCL | BT848_I2C_SDA)

static int
bttv_i2c_sendbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
{
	u32 xmit;
	int retval,cnt;

	/* sanity checks */
	if (0 == msg->len)
		return -EINVAL;

	/* start, address + first byte */
	xmit = (msg->addr << 25) | (msg->buf[0] << 16) | I2C_HW;
	if (msg->len > 1 || !last)
		xmit |= BT878_I2C_NOSTOP;
	btwrite(xmit, BT848_I2C);
	retval = bttv_i2c_wait_done(btv);
	if (retval < 0)
		goto err;
	if (retval == 0)
		goto eio;
	if (i2c_debug) {
		pr_cont(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
	}

	for (cnt = 1; cnt < msg->len; cnt++ ) {
		/* following bytes */
		xmit = (msg->buf[cnt] << 24) | I2C_HW | BT878_I2C_NOSTART;
		if (cnt < msg->len-1 || !last)
			xmit |= BT878_I2C_NOSTOP;
		btwrite(xmit, BT848_I2C);
		retval = bttv_i2c_wait_done(btv);
		if (retval < 0)
			goto err;
		if (retval == 0)
			goto eio;
		if (i2c_debug)
			pr_cont(" %02x", msg->buf[cnt]);
	}
	if (i2c_debug && !(xmit & BT878_I2C_NOSTOP))
		pr_cont(">\n");
	return msg->len;

 eio:
	retval = -EIO;
 err:
	if (i2c_debug)
		pr_cont(" ERR: %d\n",retval);
	return retval;
}

static int
bttv_i2c_readbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
{
	u32 xmit;
	u32 cnt;
	int retval;

	for (cnt = 0; cnt < msg->len; cnt++) {
		xmit = (msg->addr << 25) | (1 << 24) | I2C_HW;
		if (cnt < msg->len-1)
			xmit |= BT848_I2C_W3B;
		if (cnt < msg->len-1 || !last)
			xmit |= BT878_I2C_NOSTOP;
		if (cnt)
			xmit |= BT878_I2C_NOSTART;

		if (i2c_debug) {
			if (!(xmit & BT878_I2C_NOSTART))
				pr_cont(" <R %02x", (msg->addr << 1) +1);
		}

		btwrite(xmit, BT848_I2C);
		retval = bttv_i2c_wait_done(btv);
		if (retval < 0)
			goto err;
		if (retval == 0)
			goto eio;
		msg->buf[cnt] = ((u32)btread(BT848_I2C) >> 8) & 0xff;
		if (i2c_debug) {
			pr_cont(" =%02x", msg->buf[cnt]);
		}
		if (i2c_debug && !(xmit & BT878_I2C_NOSTOP))
			pr_cont(" >\n");
	}


	return msg->len;

 eio:
	retval = -EIO;
 err:
	if (i2c_debug)
		pr_cont(" ERR: %d\n",retval);
	return retval;
}

static int bttv_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
{
	struct v4l2_device *v4l2_dev = i2c_get_adapdata(i2c_adap);
	struct bttv *btv = to_bttv(v4l2_dev);
	int retval = 0;
	int i;

	if (i2c_debug)
		pr_debug("bt-i2c:");

	btwrite(BT848_INT_I2CDONE|BT848_INT_RACK, BT848_INT_STAT);
	for (i = 0 ; i < num; i++) {
		if (msgs[i].flags & I2C_M_RD) {
			/* read */
			retval = bttv_i2c_readbytes(btv, &msgs[i], i+1 == num);
			if (retval < 0)
				goto err;
		} else {
			/* write */
			retval = bttv_i2c_sendbytes(btv, &msgs[i], i+1 == num);
			if (retval < 0)
				goto err;
		}
	}
	return num;

 err:
	return retval;
}

static const struct i2c_algorithm bttv_algo = {
	.master_xfer   = bttv_i2c_xfer,
	.functionality = functionality,
};

/* ----------------------------------------------------------------------- */
/* I2C functions - common stuff                                            */

/* read I2C */
int bttv_I2CRead(struct bttv *btv, unsigned char addr, char *probe_for)
{
	unsigned char buffer = 0;

	if (0 != btv->i2c_rc)
		return -1;
	if (bttv_verbose && NULL != probe_for)
		pr_info("%d: i2c: checking for %s @ 0x%02x... ",
			btv->c.nr, probe_for, addr);
	btv->i2c_client.addr = addr >> 1;
	if (1 != i2c_master_recv(&btv->i2c_client, &buffer, 1)) {
		if (NULL != probe_for) {
			if (bttv_verbose)
				pr_cont("not found\n");
		} else
			pr_warn("%d: i2c read 0x%x: error\n",
				btv->c.nr, addr);
		return -1;
	}
	if (bttv_verbose && NULL != probe_for)
		pr_cont("found\n");
	return buffer;
}

/* write I2C */
int bttv_I2CWrite(struct bttv *btv, unsigned char addr, unsigned char b1,
		    unsigned char b2, int both)
{
	unsigned char buffer[2];
	int bytes = both ? 2 : 1;

	if (0 != btv->i2c_rc)
		return -1;
	btv->i2c_client.addr = addr >> 1;
	buffer[0] = b1;
	buffer[1] = b2;
	if (bytes != i2c_master_send(&btv->i2c_client, buffer, bytes))
		return -1;
	return 0;
}

/* read EEPROM content */
void bttv_readee(struct bttv *btv, unsigned char *eedata, int addr)
{
	memset(eedata, 0, 256);
	if (0 != btv->i2c_rc)
		return;
	btv->i2c_client.addr = addr >> 1;
	tveeprom_read(&btv->i2c_client, eedata, 256);
}

static char *i2c_devs[128] = {
	[ 0x1c >> 1 ] = "lgdt330x",
	[ 0x30 >> 1 ] = "IR (hauppauge)",
	[ 0x80 >> 1 ] = "msp34xx",
	[ 0x86 >> 1 ] = "tda9887",
	[ 0xa0 >> 1 ] = "eeprom",
	[ 0xc0 >> 1 ] = "tuner (analog)",
	[ 0xc2 >> 1 ] = "tuner (analog)",
};

static void do_i2c_scan(char *name, struct i2c_client *c)
{
	unsigned char buf;
	int i,rc;

	for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
		c->addr = i;
		rc = i2c_master_recv(c,&buf,0);
		if (rc < 0)
			continue;
		pr_info("%s: i2c scan: found device @ 0x%x  [%s]\n",
			name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
	}
}

/* init + register i2c adapter */
int init_bttv_i2c(struct bttv *btv)
{
	strscpy(btv->i2c_client.name, "bttv internal", I2C_NAME_SIZE);

	if (i2c_hw)
		btv->use_i2c_hw = 1;
	if (btv->use_i2c_hw) {
		/* bt878 */
		strscpy(btv->c.i2c_adap.name, "bt878",
			sizeof(btv->c.i2c_adap.name));
		btv->c.i2c_adap.algo = &bttv_algo;
	} else {
		/* bt848 */
	/* Prevents usage of invalid delay values */
		if (i2c_udelay<5)
			i2c_udelay=5;

		strscpy(btv->c.i2c_adap.name, "bttv",
			sizeof(btv->c.i2c_adap.name));
		btv->i2c_algo = bttv_i2c_algo_bit_template;
		btv->i2c_algo.udelay = i2c_udelay;
		btv->i2c_algo.data = btv;
		btv->c.i2c_adap.algo_data = &btv->i2c_algo;
	}
	btv->c.i2c_adap.owner = THIS_MODULE;

	btv->c.i2c_adap.dev.parent = &btv->c.pci->dev;
	snprintf(btv->c.i2c_adap.name, sizeof(btv->c.i2c_adap.name),
		 "bt%d #%d [%s]", btv->id, btv->c.nr,
		 btv->use_i2c_hw ? "hw" : "sw");

	i2c_set_adapdata(&btv->c.i2c_adap, &btv->c.v4l2_dev);
	btv->i2c_client.adapter = &btv->c.i2c_adap;


	if (btv->use_i2c_hw) {
		btv->i2c_rc = i2c_add_adapter(&btv->c.i2c_adap);
	} else {
		bttv_bit_setscl(btv,1);
		bttv_bit_setsda(btv,1);
		btv->i2c_rc = i2c_bit_add_bus(&btv->c.i2c_adap);
	}
	if (0 == btv->i2c_rc && i2c_scan)
		do_i2c_scan(btv->c.v4l2_dev.name, &btv->i2c_client);

	return btv->i2c_rc;
}

int fini_bttv_i2c(struct bttv *btv)
{
	if (btv->i2c_rc == 0)
		i2c_del_adapter(&btv->c.i2c_adap);

	return 0;
}