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@kernel.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, instead of software bitbang");
48 module_param(i2c_scan, int, 0444);
49 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");
50
51 static unsigned int i2c_udelay = 5;
52 module_param(i2c_udelay, int, 0444);
53 MODULE_PARM_DESC(i2c_udelay, "soft i2c delay at insmod time, in usecs (should be 5 or higher). Lower value means higher bus speed.");
54
55 /* ----------------------------------------------------------------------- */
56 /* I2C functions - bitbanging adapter (software i2c) */
57
bttv_bit_setscl(void * data,int state)58 static void bttv_bit_setscl(void *data, int state)
59 {
60 struct bttv *btv = (struct bttv*)data;
61
62 if (state)
63 btv->i2c_state |= 0x02;
64 else
65 btv->i2c_state &= ~0x02;
66 btwrite(btv->i2c_state, BT848_I2C);
67 btread(BT848_I2C);
68 }
69
bttv_bit_setsda(void * data,int state)70 static void bttv_bit_setsda(void *data, int state)
71 {
72 struct bttv *btv = (struct bttv*)data;
73
74 if (state)
75 btv->i2c_state |= 0x01;
76 else
77 btv->i2c_state &= ~0x01;
78 btwrite(btv->i2c_state, BT848_I2C);
79 btread(BT848_I2C);
80 }
81
bttv_bit_getscl(void * data)82 static int bttv_bit_getscl(void *data)
83 {
84 struct bttv *btv = (struct bttv*)data;
85 int state;
86
87 state = btread(BT848_I2C) & 0x02 ? 1 : 0;
88 return state;
89 }
90
bttv_bit_getsda(void * data)91 static int bttv_bit_getsda(void *data)
92 {
93 struct bttv *btv = (struct bttv*)data;
94 int state;
95
96 state = btread(BT848_I2C) & 0x01;
97 return state;
98 }
99
100 static const struct i2c_algo_bit_data bttv_i2c_algo_bit_template = {
101 .setsda = bttv_bit_setsda,
102 .setscl = bttv_bit_setscl,
103 .getsda = bttv_bit_getsda,
104 .getscl = bttv_bit_getscl,
105 .udelay = 16,
106 .timeout = 200,
107 };
108
109 /* ----------------------------------------------------------------------- */
110 /* I2C functions - hardware i2c */
111
functionality(struct i2c_adapter * adap)112 static u32 functionality(struct i2c_adapter *adap)
113 {
114 return I2C_FUNC_SMBUS_EMUL;
115 }
116
117 static int
bttv_i2c_wait_done(struct bttv * btv)118 bttv_i2c_wait_done(struct bttv *btv)
119 {
120 int rc = 0;
121
122 /* timeout */
123 if (wait_event_interruptible_timeout(btv->i2c_queue,
124 btv->i2c_done, msecs_to_jiffies(85)) == -ERESTARTSYS)
125 rc = -EIO;
126
127 if (btv->i2c_done & BT848_INT_RACK)
128 rc = 1;
129 btv->i2c_done = 0;
130 return rc;
131 }
132
133 #define I2C_HW (BT878_I2C_MODE | BT848_I2C_SYNC |\
134 BT848_I2C_SCL | BT848_I2C_SDA)
135
136 static int
bttv_i2c_sendbytes(struct bttv * btv,const struct i2c_msg * msg,int last)137 bttv_i2c_sendbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
138 {
139 u32 xmit;
140 int retval,cnt;
141
142 /* sanity checks */
143 if (0 == msg->len)
144 return -EINVAL;
145
146 /* start, address + first byte */
147 xmit = (msg->addr << 25) | (msg->buf[0] << 16) | I2C_HW;
148 if (msg->len > 1 || !last)
149 xmit |= BT878_I2C_NOSTOP;
150 btwrite(xmit, BT848_I2C);
151 retval = bttv_i2c_wait_done(btv);
152 if (retval < 0)
153 goto err;
154 if (retval == 0)
155 goto eio;
156 if (i2c_debug) {
157 pr_cont(" <W %02x %02x", msg->addr << 1, msg->buf[0]);
158 }
159
160 for (cnt = 1; cnt < msg->len; cnt++ ) {
161 /* following bytes */
162 xmit = (msg->buf[cnt] << 24) | I2C_HW | BT878_I2C_NOSTART;
163 if (cnt < msg->len-1 || !last)
164 xmit |= BT878_I2C_NOSTOP;
165 btwrite(xmit, BT848_I2C);
166 retval = bttv_i2c_wait_done(btv);
167 if (retval < 0)
168 goto err;
169 if (retval == 0)
170 goto eio;
171 if (i2c_debug)
172 pr_cont(" %02x", msg->buf[cnt]);
173 }
174 if (i2c_debug && !(xmit & BT878_I2C_NOSTOP))
175 pr_cont(">\n");
176 return msg->len;
177
178 eio:
179 retval = -EIO;
180 err:
181 if (i2c_debug)
182 pr_cont(" ERR: %d\n",retval);
183 return retval;
184 }
185
186 static int
bttv_i2c_readbytes(struct bttv * btv,const struct i2c_msg * msg,int last)187 bttv_i2c_readbytes(struct bttv *btv, const struct i2c_msg *msg, int last)
188 {
189 u32 xmit;
190 u32 cnt;
191 int retval;
192
193 for (cnt = 0; cnt < msg->len; cnt++) {
194 xmit = (msg->addr << 25) | (1 << 24) | I2C_HW;
195 if (cnt < msg->len-1)
196 xmit |= BT848_I2C_W3B;
197 if (cnt < msg->len-1 || !last)
198 xmit |= BT878_I2C_NOSTOP;
199 if (cnt)
200 xmit |= BT878_I2C_NOSTART;
201
202 if (i2c_debug) {
203 if (!(xmit & BT878_I2C_NOSTART))
204 pr_cont(" <R %02x", (msg->addr << 1) +1);
205 }
206
207 btwrite(xmit, BT848_I2C);
208 retval = bttv_i2c_wait_done(btv);
209 if (retval < 0)
210 goto err;
211 if (retval == 0)
212 goto eio;
213 msg->buf[cnt] = ((u32)btread(BT848_I2C) >> 8) & 0xff;
214 if (i2c_debug) {
215 pr_cont(" =%02x", msg->buf[cnt]);
216 }
217 if (i2c_debug && !(xmit & BT878_I2C_NOSTOP))
218 pr_cont(" >\n");
219 }
220
221
222 return msg->len;
223
224 eio:
225 retval = -EIO;
226 err:
227 if (i2c_debug)
228 pr_cont(" ERR: %d\n",retval);
229 return retval;
230 }
231
bttv_i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg * msgs,int num)232 static int bttv_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
233 {
234 struct v4l2_device *v4l2_dev = i2c_get_adapdata(i2c_adap);
235 struct bttv *btv = to_bttv(v4l2_dev);
236 int retval = 0;
237 int i;
238
239 if (i2c_debug)
240 pr_debug("bt-i2c:");
241
242 btwrite(BT848_INT_I2CDONE|BT848_INT_RACK, BT848_INT_STAT);
243 for (i = 0 ; i < num; i++) {
244 if (msgs[i].flags & I2C_M_RD) {
245 /* read */
246 retval = bttv_i2c_readbytes(btv, &msgs[i], i+1 == num);
247 if (retval < 0)
248 goto err;
249 } else {
250 /* write */
251 retval = bttv_i2c_sendbytes(btv, &msgs[i], i+1 == num);
252 if (retval < 0)
253 goto err;
254 }
255 }
256 return num;
257
258 err:
259 return retval;
260 }
261
262 static const struct i2c_algorithm bttv_algo = {
263 .master_xfer = bttv_i2c_xfer,
264 .functionality = functionality,
265 };
266
267 /* ----------------------------------------------------------------------- */
268 /* I2C functions - common stuff */
269
270 /* read I2C */
bttv_I2CRead(struct bttv * btv,unsigned char addr,char * probe_for)271 int bttv_I2CRead(struct bttv *btv, unsigned char addr, char *probe_for)
272 {
273 unsigned char buffer = 0;
274
275 if (0 != btv->i2c_rc)
276 return -1;
277 if (bttv_verbose && NULL != probe_for)
278 pr_info("%d: i2c: checking for %s @ 0x%02x... ",
279 btv->c.nr, probe_for, addr);
280 btv->i2c_client.addr = addr >> 1;
281 if (1 != i2c_master_recv(&btv->i2c_client, &buffer, 1)) {
282 if (NULL != probe_for) {
283 if (bttv_verbose)
284 pr_cont("not found\n");
285 } else
286 pr_warn("%d: i2c read 0x%x: error\n",
287 btv->c.nr, addr);
288 return -1;
289 }
290 if (bttv_verbose && NULL != probe_for)
291 pr_cont("found\n");
292 return buffer;
293 }
294
295 /* write I2C */
bttv_I2CWrite(struct bttv * btv,unsigned char addr,unsigned char b1,unsigned char b2,int both)296 int bttv_I2CWrite(struct bttv *btv, unsigned char addr, unsigned char b1,
297 unsigned char b2, int both)
298 {
299 unsigned char buffer[2];
300 int bytes = both ? 2 : 1;
301
302 if (0 != btv->i2c_rc)
303 return -1;
304 btv->i2c_client.addr = addr >> 1;
305 buffer[0] = b1;
306 buffer[1] = b2;
307 if (bytes != i2c_master_send(&btv->i2c_client, buffer, bytes))
308 return -1;
309 return 0;
310 }
311
312 /* read EEPROM content */
bttv_readee(struct bttv * btv,unsigned char * eedata,int addr)313 void bttv_readee(struct bttv *btv, unsigned char *eedata, int addr)
314 {
315 memset(eedata, 0, 256);
316 if (0 != btv->i2c_rc)
317 return;
318 btv->i2c_client.addr = addr >> 1;
319 tveeprom_read(&btv->i2c_client, eedata, 256);
320 }
321
322 static char *i2c_devs[128] = {
323 [ 0x1c >> 1 ] = "lgdt330x",
324 [ 0x30 >> 1 ] = "IR (hauppauge)",
325 [ 0x80 >> 1 ] = "msp34xx",
326 [ 0x86 >> 1 ] = "tda9887",
327 [ 0xa0 >> 1 ] = "eeprom",
328 [ 0xc0 >> 1 ] = "tuner (analog)",
329 [ 0xc2 >> 1 ] = "tuner (analog)",
330 };
331
do_i2c_scan(char * name,struct i2c_client * c)332 static void do_i2c_scan(char *name, struct i2c_client *c)
333 {
334 unsigned char buf;
335 int i,rc;
336
337 for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
338 c->addr = i;
339 rc = i2c_master_recv(c,&buf,0);
340 if (rc < 0)
341 continue;
342 pr_info("%s: i2c scan: found device @ 0x%x [%s]\n",
343 name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
344 }
345 }
346
347 /* init + register i2c adapter */
init_bttv_i2c(struct bttv * btv)348 int init_bttv_i2c(struct bttv *btv)
349 {
350 strlcpy(btv->i2c_client.name, "bttv internal", I2C_NAME_SIZE);
351
352 if (i2c_hw)
353 btv->use_i2c_hw = 1;
354 if (btv->use_i2c_hw) {
355 /* bt878 */
356 strlcpy(btv->c.i2c_adap.name, "bt878",
357 sizeof(btv->c.i2c_adap.name));
358 btv->c.i2c_adap.algo = &bttv_algo;
359 } else {
360 /* bt848 */
361 /* Prevents usage of invalid delay values */
362 if (i2c_udelay<5)
363 i2c_udelay=5;
364
365 strlcpy(btv->c.i2c_adap.name, "bttv",
366 sizeof(btv->c.i2c_adap.name));
367 btv->i2c_algo = bttv_i2c_algo_bit_template;
368 btv->i2c_algo.udelay = i2c_udelay;
369 btv->i2c_algo.data = btv;
370 btv->c.i2c_adap.algo_data = &btv->i2c_algo;
371 }
372 btv->c.i2c_adap.owner = THIS_MODULE;
373
374 btv->c.i2c_adap.dev.parent = &btv->c.pci->dev;
375 snprintf(btv->c.i2c_adap.name, sizeof(btv->c.i2c_adap.name),
376 "bt%d #%d [%s]", btv->id, btv->c.nr,
377 btv->use_i2c_hw ? "hw" : "sw");
378
379 i2c_set_adapdata(&btv->c.i2c_adap, &btv->c.v4l2_dev);
380 btv->i2c_client.adapter = &btv->c.i2c_adap;
381
382
383 if (btv->use_i2c_hw) {
384 btv->i2c_rc = i2c_add_adapter(&btv->c.i2c_adap);
385 } else {
386 bttv_bit_setscl(btv,1);
387 bttv_bit_setsda(btv,1);
388 btv->i2c_rc = i2c_bit_add_bus(&btv->c.i2c_adap);
389 }
390 if (0 == btv->i2c_rc && i2c_scan)
391 do_i2c_scan(btv->c.v4l2_dev.name, &btv->i2c_client);
392
393 return btv->i2c_rc;
394 }
395
fini_bttv_i2c(struct bttv * btv)396 int fini_bttv_i2c(struct bttv *btv)
397 {
398 if (btv->i2c_rc == 0)
399 i2c_del_adapter(&btv->c.i2c_adap);
400
401 return 0;
402 }
403
