1 /*
2
3 bttv-i2c.c -- all the i2c code is here
4
5 bttv - Bt848 frame grabber driver
6
7 Copyright (C) 1996,97,98 Ralph Metzler (rjkm@thp.uni-koeln.de)
8 & Marcus Metzler (mocm@thp.uni-koeln.de)
9 (c) 1999-2003 Gerd Knorr <kraxel@bytesex.org>
10
11 (c) 2005 Mauro Carvalho Chehab <mchehab@infradead.org>
12 - Multituner support and i2c address binding
13
14 This program is free software; you can redistribute it and/or modify
15 it under the terms of the GNU General Public License as published by
16 the Free Software Foundation; either version 2 of the License, or
17 (at your option) any later version.
18
19 This program is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 GNU General Public License for more details.
23
24 You should have received a copy of the GNU General Public License
25 along with this program; if not, write to the Free Software
26 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
27
28 */
29
30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
31
32 #include <linux/module.h>
33 #include <linux/init.h>
34 #include <linux/delay.h>
35
36 #include "bttvp.h"
37 #include <media/v4l2-common.h>
38 #include <linux/jiffies.h>
39 #include <asm/io.h>
40
41 static int i2c_debug;
42 static int i2c_hw;
43 static int i2c_scan;
44 module_param(i2c_debug, int, 0644);
45 MODULE_PARM_DESC(i2c_debug, "configure i2c debug level");
46 module_param(i2c_hw, int, 0444);
47 MODULE_PARM_DESC(i2c_hw,"force use of hardware i2c support, "
48 "instead of software bitbang");
49 module_param(i2c_scan, int, 0444);
50 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");
51
52 static unsigned int i2c_udelay = 5;
53 module_param(i2c_udelay, int, 0444);
54 MODULE_PARM_DESC(i2c_udelay,"soft i2c delay at insmod time, in usecs "
55 "(should be 5 or higher). Lower value means higher bus speed.");
56
57 /* ----------------------------------------------------------------------- */
58 /* I2C functions - bitbanging adapter (software i2c) */
59
bttv_bit_setscl(void * data,int state)60 static void bttv_bit_setscl(void *data, int state)
61 {
62 struct bttv *btv = (struct bttv*)data;
63
64 if (state)
65 btv->i2c_state |= 0x02;
66 else
67 btv->i2c_state &= ~0x02;
68 btwrite(btv->i2c_state, BT848_I2C);
69 btread(BT848_I2C);
70 }
71
bttv_bit_setsda(void * data,int state)72 static void bttv_bit_setsda(void *data, int state)
73 {
74 struct bttv *btv = (struct bttv*)data;
75
76 if (state)
77 btv->i2c_state |= 0x01;
78 else
79 btv->i2c_state &= ~0x01;
80 btwrite(btv->i2c_state, BT848_I2C);
81 btread(BT848_I2C);
82 }
83
bttv_bit_getscl(void * data)84 static int bttv_bit_getscl(void *data)
85 {
86 struct bttv *btv = (struct bttv*)data;
87 int state;
88
89 state = btread(BT848_I2C) & 0x02 ? 1 : 0;
90 return state;
91 }
92
bttv_bit_getsda(void * data)93 static int bttv_bit_getsda(void *data)
94 {
95 struct bttv *btv = (struct bttv*)data;
96 int state;
97
98 state = btread(BT848_I2C) & 0x01;
99 return state;
100 }
101
102 static struct i2c_algo_bit_data __devinitdata bttv_i2c_algo_bit_template = {
103 .setsda = bttv_bit_setsda,
104 .setscl = bttv_bit_setscl,
105 .getsda = bttv_bit_getsda,
106 .getscl = bttv_bit_getscl,
107 .udelay = 16,
108 .timeout = 200,
109 };
110
111 /* ----------------------------------------------------------------------- */
112 /* I2C functions - hardware i2c */
113
functionality(struct i2c_adapter * adap)114 static u32 functionality(struct i2c_adapter *adap)
115 {
116 return I2C_FUNC_SMBUS_EMUL;
117 }
118
119 static int
bttv_i2c_wait_done(struct bttv * btv)120 bttv_i2c_wait_done(struct bttv *btv)
121 {
122 int rc = 0;
123
124 /* timeout */
125 if (wait_event_interruptible_timeout(btv->i2c_queue,
126 btv->i2c_done, msecs_to_jiffies(85)) == -ERESTARTSYS)
127 rc = -EIO;
128
129 if (btv->i2c_done & BT848_INT_RACK)
130 rc = 1;
131 btv->i2c_done = 0;
132 return rc;
133 }
134
135 #define I2C_HW (BT878_I2C_MODE | BT848_I2C_SYNC |\
136 BT848_I2C_SCL | BT848_I2C_SDA)
137
138 static int
bttv_i2c_sendbytes(struct bttv * btv,const struct i2c_msg * msg,int last)139 bttv_i2c_sendbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
140 {
141 u32 xmit;
142 int retval,cnt;
143
144 /* sanity checks */
145 if (0 == msg->len)
146 return -EINVAL;
147
148 /* start, address + first byte */
149 xmit = (msg->addr << 25) | (msg->buf[0] << 16) | I2C_HW;
150 if (msg->len > 1 || !last)
151 xmit |= BT878_I2C_NOSTOP;
152 btwrite(xmit, BT848_I2C);
153 retval = bttv_i2c_wait_done(btv);
154 if (retval < 0)
155 goto err;
156 if (retval == 0)
157 goto eio;
158 if (i2c_debug) {
159 pr_cont(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
160 }
161
162 for (cnt = 1; cnt < msg->len; cnt++ ) {
163 /* following bytes */
164 xmit = (msg->buf[cnt] << 24) | I2C_HW | BT878_I2C_NOSTART;
165 if (cnt < msg->len-1 || !last)
166 xmit |= BT878_I2C_NOSTOP;
167 btwrite(xmit, BT848_I2C);
168 retval = bttv_i2c_wait_done(btv);
169 if (retval < 0)
170 goto err;
171 if (retval == 0)
172 goto eio;
173 if (i2c_debug)
174 pr_cont(" %02x", msg->buf[cnt]);
175 }
176 if (!(xmit & BT878_I2C_NOSTOP))
177 pr_cont(">\n");
178 return msg->len;
179
180 eio:
181 retval = -EIO;
182 err:
183 if (i2c_debug)
184 pr_cont(" ERR: %d\n",retval);
185 return retval;
186 }
187
188 static int
bttv_i2c_readbytes(struct bttv * btv,const struct i2c_msg * msg,int last)189 bttv_i2c_readbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
190 {
191 u32 xmit;
192 u32 cnt;
193 int retval;
194
195 for (cnt = 0; cnt < msg->len; cnt++) {
196 xmit = (msg->addr << 25) | (1 << 24) | I2C_HW;
197 if (cnt < msg->len-1)
198 xmit |= BT848_I2C_W3B;
199 if (cnt < msg->len-1 || !last)
200 xmit |= BT878_I2C_NOSTOP;
201 if (cnt)
202 xmit |= BT878_I2C_NOSTART;
203
204 if (i2c_debug) {
205 if (!(xmit & BT878_I2C_NOSTART))
206 pr_cont(" <R %02x", (msg->addr << 1) +1);
207 }
208
209 btwrite(xmit, BT848_I2C);
210 retval = bttv_i2c_wait_done(btv);
211 if (retval < 0)
212 goto err;
213 if (retval == 0)
214 goto eio;
215 msg->buf[cnt] = ((u32)btread(BT848_I2C) >> 8) & 0xff;
216 if (i2c_debug) {
217 pr_cont(" =%02x", msg->buf[cnt]);
218 }
219 if (i2c_debug && !(xmit & BT878_I2C_NOSTOP))
220 pr_cont(" >\n");
221 }
222
223
224 return msg->len;
225
226 eio:
227 retval = -EIO;
228 err:
229 if (i2c_debug)
230 pr_cont(" ERR: %d\n",retval);
231 return retval;
232 }
233
bttv_i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg * msgs,int num)234 static int bttv_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
235 {
236 struct v4l2_device *v4l2_dev = i2c_get_adapdata(i2c_adap);
237 struct bttv *btv = to_bttv(v4l2_dev);
238 int retval = 0;
239 int i;
240
241 if (i2c_debug)
242 pr_debug("bt-i2c:");
243
244 btwrite(BT848_INT_I2CDONE|BT848_INT_RACK, BT848_INT_STAT);
245 for (i = 0 ; i < num; i++) {
246 if (msgs[i].flags & I2C_M_RD) {
247 /* read */
248 retval = bttv_i2c_readbytes(btv, &msgs[i], i+1 == num);
249 if (retval < 0)
250 goto err;
251 } else {
252 /* write */
253 retval = bttv_i2c_sendbytes(btv, &msgs[i], i+1 == num);
254 if (retval < 0)
255 goto err;
256 }
257 }
258 return num;
259
260 err:
261 return retval;
262 }
263
264 static const struct i2c_algorithm bttv_algo = {
265 .master_xfer = bttv_i2c_xfer,
266 .functionality = functionality,
267 };
268
269 /* ----------------------------------------------------------------------- */
270 /* I2C functions - common stuff */
271
272 /* read I2C */
bttv_I2CRead(struct bttv * btv,unsigned char addr,char * probe_for)273 int bttv_I2CRead(struct bttv *btv, unsigned char addr, char *probe_for)
274 {
275 unsigned char buffer = 0;
276
277 if (0 != btv->i2c_rc)
278 return -1;
279 if (bttv_verbose && NULL != probe_for)
280 pr_info("%d: i2c: checking for %s @ 0x%02x... ",
281 btv->c.nr, probe_for, addr);
282 btv->i2c_client.addr = addr >> 1;
283 if (1 != i2c_master_recv(&btv->i2c_client, &buffer, 1)) {
284 if (NULL != probe_for) {
285 if (bttv_verbose)
286 pr_cont("not found\n");
287 } else
288 pr_warn("%d: i2c read 0x%x: error\n",
289 btv->c.nr, addr);
290 return -1;
291 }
292 if (bttv_verbose && NULL != probe_for)
293 pr_cont("found\n");
294 return buffer;
295 }
296
297 /* write I2C */
bttv_I2CWrite(struct bttv * btv,unsigned char addr,unsigned char b1,unsigned char b2,int both)298 int bttv_I2CWrite(struct bttv *btv, unsigned char addr, unsigned char b1,
299 unsigned char b2, int both)
300 {
301 unsigned char buffer[2];
302 int bytes = both ? 2 : 1;
303
304 if (0 != btv->i2c_rc)
305 return -1;
306 btv->i2c_client.addr = addr >> 1;
307 buffer[0] = b1;
308 buffer[1] = b2;
309 if (bytes != i2c_master_send(&btv->i2c_client, buffer, bytes))
310 return -1;
311 return 0;
312 }
313
314 /* read EEPROM content */
bttv_readee(struct bttv * btv,unsigned char * eedata,int addr)315 void __devinit bttv_readee(struct bttv *btv, unsigned char *eedata, int addr)
316 {
317 memset(eedata, 0, 256);
318 if (0 != btv->i2c_rc)
319 return;
320 btv->i2c_client.addr = addr >> 1;
321 tveeprom_read(&btv->i2c_client, eedata, 256);
322 }
323
324 static char *i2c_devs[128] = {
325 [ 0x1c >> 1 ] = "lgdt330x",
326 [ 0x30 >> 1 ] = "IR (hauppauge)",
327 [ 0x80 >> 1 ] = "msp34xx",
328 [ 0x86 >> 1 ] = "tda9887",
329 [ 0xa0 >> 1 ] = "eeprom",
330 [ 0xc0 >> 1 ] = "tuner (analog)",
331 [ 0xc2 >> 1 ] = "tuner (analog)",
332 };
333
do_i2c_scan(char * name,struct i2c_client * c)334 static void do_i2c_scan(char *name, struct i2c_client *c)
335 {
336 unsigned char buf;
337 int i,rc;
338
339 for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
340 c->addr = i;
341 rc = i2c_master_recv(c,&buf,0);
342 if (rc < 0)
343 continue;
344 pr_info("%s: i2c scan: found device @ 0x%x [%s]\n",
345 name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
346 }
347 }
348
349 /* init + register i2c adapter */
init_bttv_i2c(struct bttv * btv)350 int __devinit init_bttv_i2c(struct bttv *btv)
351 {
352 strlcpy(btv->i2c_client.name, "bttv internal", I2C_NAME_SIZE);
353
354 if (i2c_hw)
355 btv->use_i2c_hw = 1;
356 if (btv->use_i2c_hw) {
357 /* bt878 */
358 strlcpy(btv->c.i2c_adap.name, "bt878",
359 sizeof(btv->c.i2c_adap.name));
360 btv->c.i2c_adap.algo = &bttv_algo;
361 } else {
362 /* bt848 */
363 /* Prevents usage of invalid delay values */
364 if (i2c_udelay<5)
365 i2c_udelay=5;
366
367 strlcpy(btv->c.i2c_adap.name, "bttv",
368 sizeof(btv->c.i2c_adap.name));
369 memcpy(&btv->i2c_algo, &bttv_i2c_algo_bit_template,
370 sizeof(bttv_i2c_algo_bit_template));
371 btv->i2c_algo.udelay = i2c_udelay;
372 btv->i2c_algo.data = btv;
373 btv->c.i2c_adap.algo_data = &btv->i2c_algo;
374 }
375 btv->c.i2c_adap.owner = THIS_MODULE;
376
377 btv->c.i2c_adap.dev.parent = &btv->c.pci->dev;
378 snprintf(btv->c.i2c_adap.name, sizeof(btv->c.i2c_adap.name),
379 "bt%d #%d [%s]", btv->id, btv->c.nr,
380 btv->use_i2c_hw ? "hw" : "sw");
381
382 i2c_set_adapdata(&btv->c.i2c_adap, &btv->c.v4l2_dev);
383 btv->i2c_client.adapter = &btv->c.i2c_adap;
384
385
386 if (btv->use_i2c_hw) {
387 btv->i2c_rc = i2c_add_adapter(&btv->c.i2c_adap);
388 } else {
389 bttv_bit_setscl(btv,1);
390 bttv_bit_setsda(btv,1);
391 btv->i2c_rc = i2c_bit_add_bus(&btv->c.i2c_adap);
392 }
393 if (0 == btv->i2c_rc && i2c_scan)
394 do_i2c_scan(btv->c.v4l2_dev.name, &btv->i2c_client);
395
396 return btv->i2c_rc;
397 }
398