1 /*
2 * Driver for the Auvitek AU0828 USB bridge
3 *
4 * Copyright (c) 2008 Steven Toth <stoth@linuxtv.org>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 *
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 */
21
22 #include "au0828.h"
23
24 #include <linux/module.h>
25 #include <linux/moduleparam.h>
26 #include <linux/init.h>
27 #include <linux/delay.h>
28 #include <linux/io.h>
29
30 #include "media/tuner.h"
31 #include <media/v4l2-common.h>
32
33 static int i2c_scan;
34 module_param(i2c_scan, int, 0444);
35 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
36
37 #define I2C_WAIT_DELAY 25
38 #define I2C_WAIT_RETRY 1000
39
i2c_slave_did_write_ack(struct i2c_adapter * i2c_adap)40 static inline int i2c_slave_did_write_ack(struct i2c_adapter *i2c_adap)
41 {
42 struct au0828_dev *dev = i2c_adap->algo_data;
43 return au0828_read(dev, AU0828_I2C_STATUS_201) &
44 AU0828_I2C_STATUS_NO_WRITE_ACK ? 0 : 1;
45 }
46
i2c_slave_did_read_ack(struct i2c_adapter * i2c_adap)47 static inline int i2c_slave_did_read_ack(struct i2c_adapter *i2c_adap)
48 {
49 struct au0828_dev *dev = i2c_adap->algo_data;
50 return au0828_read(dev, AU0828_I2C_STATUS_201) &
51 AU0828_I2C_STATUS_NO_READ_ACK ? 0 : 1;
52 }
53
i2c_wait_read_ack(struct i2c_adapter * i2c_adap)54 static int i2c_wait_read_ack(struct i2c_adapter *i2c_adap)
55 {
56 int count;
57
58 for (count = 0; count < I2C_WAIT_RETRY; count++) {
59 if (!i2c_slave_did_read_ack(i2c_adap))
60 break;
61 udelay(I2C_WAIT_DELAY);
62 }
63
64 if (I2C_WAIT_RETRY == count)
65 return 0;
66
67 return 1;
68 }
69
i2c_is_read_busy(struct i2c_adapter * i2c_adap)70 static inline int i2c_is_read_busy(struct i2c_adapter *i2c_adap)
71 {
72 struct au0828_dev *dev = i2c_adap->algo_data;
73 return au0828_read(dev, AU0828_I2C_STATUS_201) &
74 AU0828_I2C_STATUS_READ_DONE ? 0 : 1;
75 }
76
i2c_wait_read_done(struct i2c_adapter * i2c_adap)77 static int i2c_wait_read_done(struct i2c_adapter *i2c_adap)
78 {
79 int count;
80
81 for (count = 0; count < I2C_WAIT_RETRY; count++) {
82 if (!i2c_is_read_busy(i2c_adap))
83 break;
84 udelay(I2C_WAIT_DELAY);
85 }
86
87 if (I2C_WAIT_RETRY == count)
88 return 0;
89
90 return 1;
91 }
92
i2c_is_write_done(struct i2c_adapter * i2c_adap)93 static inline int i2c_is_write_done(struct i2c_adapter *i2c_adap)
94 {
95 struct au0828_dev *dev = i2c_adap->algo_data;
96 return au0828_read(dev, AU0828_I2C_STATUS_201) &
97 AU0828_I2C_STATUS_WRITE_DONE ? 1 : 0;
98 }
99
i2c_wait_write_done(struct i2c_adapter * i2c_adap)100 static int i2c_wait_write_done(struct i2c_adapter *i2c_adap)
101 {
102 int count;
103
104 for (count = 0; count < I2C_WAIT_RETRY; count++) {
105 if (i2c_is_write_done(i2c_adap))
106 break;
107 udelay(I2C_WAIT_DELAY);
108 }
109
110 if (I2C_WAIT_RETRY == count)
111 return 0;
112
113 return 1;
114 }
115
i2c_is_busy(struct i2c_adapter * i2c_adap)116 static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
117 {
118 struct au0828_dev *dev = i2c_adap->algo_data;
119 return au0828_read(dev, AU0828_I2C_STATUS_201) &
120 AU0828_I2C_STATUS_BUSY ? 1 : 0;
121 }
122
i2c_wait_done(struct i2c_adapter * i2c_adap)123 static int i2c_wait_done(struct i2c_adapter *i2c_adap)
124 {
125 int count;
126
127 for (count = 0; count < I2C_WAIT_RETRY; count++) {
128 if (!i2c_is_busy(i2c_adap))
129 break;
130 udelay(I2C_WAIT_DELAY);
131 }
132
133 if (I2C_WAIT_RETRY == count)
134 return 0;
135
136 return 1;
137 }
138
139 /* FIXME: Implement join handling correctly */
i2c_sendbytes(struct i2c_adapter * i2c_adap,const struct i2c_msg * msg,int joined_rlen)140 static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
141 const struct i2c_msg *msg, int joined_rlen)
142 {
143 int i, strobe = 0;
144 struct au0828_dev *dev = i2c_adap->algo_data;
145 u8 i2c_speed = dev->board.i2c_clk_divider;
146
147 dprintk(4, "%s()\n", __func__);
148
149 au0828_write(dev, AU0828_I2C_MULTIBYTE_MODE_2FF, 0x01);
150
151 if (((dev->board.tuner_type == TUNER_XC5000) ||
152 (dev->board.tuner_type == TUNER_XC5000C)) &&
153 (dev->board.tuner_addr == msg->addr)) {
154 /*
155 * Due to I2C clock stretch, we need to use a lower speed
156 * on xc5000 for commands. However, firmware transfer can
157 * speed up to 400 KHz.
158 */
159 if (msg->len == 64)
160 i2c_speed = AU0828_I2C_CLK_250KHZ;
161 else
162 i2c_speed = AU0828_I2C_CLK_20KHZ;
163 }
164 /* Set the I2C clock */
165 au0828_write(dev, AU0828_I2C_CLK_DIVIDER_202, i2c_speed);
166
167 /* Hardware needs 8 bit addresses */
168 au0828_write(dev, AU0828_I2C_DEST_ADDR_203, msg->addr << 1);
169
170 dprintk(4, "SEND: %02x\n", msg->addr);
171
172 /* Deal with i2c_scan */
173 if (msg->len == 0) {
174 /* The analog tuner detection code makes use of the SMBUS_QUICK
175 message (which involves a zero length i2c write). To avoid
176 checking the status register when we didn't strobe out any
177 actual bytes to the bus, just do a read check. This is
178 consistent with how I saw i2c device checking done in the
179 USB trace of the Windows driver */
180 au0828_write(dev, AU0828_I2C_TRIGGER_200,
181 AU0828_I2C_TRIGGER_READ);
182
183 if (!i2c_wait_done(i2c_adap))
184 return -EIO;
185
186 if (i2c_wait_read_ack(i2c_adap))
187 return -EIO;
188
189 return 0;
190 }
191
192 for (i = 0; i < msg->len;) {
193
194 dprintk(4, " %02x\n", msg->buf[i]);
195
196 au0828_write(dev, AU0828_I2C_WRITE_FIFO_205, msg->buf[i]);
197
198 strobe++;
199 i++;
200
201 if ((strobe >= 4) || (i >= msg->len)) {
202
203 /* Strobe the byte into the bus */
204 if (i < msg->len)
205 au0828_write(dev, AU0828_I2C_TRIGGER_200,
206 AU0828_I2C_TRIGGER_WRITE |
207 AU0828_I2C_TRIGGER_HOLD);
208 else
209 au0828_write(dev, AU0828_I2C_TRIGGER_200,
210 AU0828_I2C_TRIGGER_WRITE);
211
212 /* Reset strobe trigger */
213 strobe = 0;
214
215 if (!i2c_wait_write_done(i2c_adap))
216 return -EIO;
217
218 }
219
220 }
221 if (!i2c_wait_done(i2c_adap))
222 return -EIO;
223
224 dprintk(4, "\n");
225
226 return msg->len;
227 }
228
229 /* FIXME: Implement join handling correctly */
i2c_readbytes(struct i2c_adapter * i2c_adap,const struct i2c_msg * msg,int joined)230 static int i2c_readbytes(struct i2c_adapter *i2c_adap,
231 const struct i2c_msg *msg, int joined)
232 {
233 struct au0828_dev *dev = i2c_adap->algo_data;
234 u8 i2c_speed = dev->board.i2c_clk_divider;
235 int i;
236
237 dprintk(4, "%s()\n", __func__);
238
239 au0828_write(dev, AU0828_I2C_MULTIBYTE_MODE_2FF, 0x01);
240
241 /*
242 * Due to xc5000c clock stretch, we cannot use full speed at
243 * readings from xc5000, as otherwise they'll fail.
244 */
245 if (((dev->board.tuner_type == TUNER_XC5000) ||
246 (dev->board.tuner_type == TUNER_XC5000C)) &&
247 (dev->board.tuner_addr == msg->addr))
248 i2c_speed = AU0828_I2C_CLK_20KHZ;
249
250 /* Set the I2C clock */
251 au0828_write(dev, AU0828_I2C_CLK_DIVIDER_202, i2c_speed);
252
253 /* Hardware needs 8 bit addresses */
254 au0828_write(dev, AU0828_I2C_DEST_ADDR_203, msg->addr << 1);
255
256 dprintk(4, " RECV:\n");
257
258 /* Deal with i2c_scan */
259 if (msg->len == 0) {
260 au0828_write(dev, AU0828_I2C_TRIGGER_200,
261 AU0828_I2C_TRIGGER_READ);
262
263 if (i2c_wait_read_ack(i2c_adap))
264 return -EIO;
265 return 0;
266 }
267
268 for (i = 0; i < msg->len;) {
269
270 i++;
271
272 if (i < msg->len)
273 au0828_write(dev, AU0828_I2C_TRIGGER_200,
274 AU0828_I2C_TRIGGER_READ |
275 AU0828_I2C_TRIGGER_HOLD);
276 else
277 au0828_write(dev, AU0828_I2C_TRIGGER_200,
278 AU0828_I2C_TRIGGER_READ);
279
280 if (!i2c_wait_read_done(i2c_adap))
281 return -EIO;
282
283 msg->buf[i-1] = au0828_read(dev, AU0828_I2C_READ_FIFO_209) &
284 0xff;
285
286 dprintk(4, " %02x\n", msg->buf[i-1]);
287 }
288 if (!i2c_wait_done(i2c_adap))
289 return -EIO;
290
291 dprintk(4, "\n");
292
293 return msg->len;
294 }
295
i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg * msgs,int num)296 static int i2c_xfer(struct i2c_adapter *i2c_adap,
297 struct i2c_msg *msgs, int num)
298 {
299 int i, retval = 0;
300
301 dprintk(4, "%s(num = %d)\n", __func__, num);
302
303 for (i = 0; i < num; i++) {
304 dprintk(4, "%s(num = %d) addr = 0x%02x len = 0x%x\n",
305 __func__, num, msgs[i].addr, msgs[i].len);
306 if (msgs[i].flags & I2C_M_RD) {
307 /* read */
308 retval = i2c_readbytes(i2c_adap, &msgs[i], 0);
309 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
310 msgs[i].addr == msgs[i + 1].addr) {
311 /* write then read from same address */
312 retval = i2c_sendbytes(i2c_adap, &msgs[i],
313 msgs[i + 1].len);
314 if (retval < 0)
315 goto err;
316 i++;
317 retval = i2c_readbytes(i2c_adap, &msgs[i], 1);
318 } else {
319 /* write */
320 retval = i2c_sendbytes(i2c_adap, &msgs[i], 0);
321 }
322 if (retval < 0)
323 goto err;
324 }
325 return num;
326
327 err:
328 return retval;
329 }
330
au0828_functionality(struct i2c_adapter * adap)331 static u32 au0828_functionality(struct i2c_adapter *adap)
332 {
333 return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
334 }
335
336 static struct i2c_algorithm au0828_i2c_algo_template = {
337 .master_xfer = i2c_xfer,
338 .functionality = au0828_functionality,
339 };
340
341 /* ----------------------------------------------------------------------- */
342
343 static struct i2c_adapter au0828_i2c_adap_template = {
344 .name = KBUILD_MODNAME,
345 .owner = THIS_MODULE,
346 .algo = &au0828_i2c_algo_template,
347 };
348
349 static struct i2c_client au0828_i2c_client_template = {
350 .name = "au0828 internal",
351 };
352
353 static char *i2c_devs[128] = {
354 [0x8e >> 1] = "au8522",
355 [0xa0 >> 1] = "eeprom",
356 [0xc2 >> 1] = "tuner/xc5000",
357 };
358
do_i2c_scan(char * name,struct i2c_client * c)359 static void do_i2c_scan(char *name, struct i2c_client *c)
360 {
361 unsigned char buf;
362 int i, rc;
363
364 for (i = 0; i < 128; i++) {
365 c->addr = i;
366 rc = i2c_master_recv(c, &buf, 0);
367 if (rc < 0)
368 continue;
369 pr_info("%s: i2c scan: found device @ 0x%x [%s]\n",
370 name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
371 }
372 }
373
374 /* init + register i2c adapter */
au0828_i2c_register(struct au0828_dev * dev)375 int au0828_i2c_register(struct au0828_dev *dev)
376 {
377 dprintk(1, "%s()\n", __func__);
378
379 dev->i2c_adap = au0828_i2c_adap_template;
380 dev->i2c_algo = au0828_i2c_algo_template;
381 dev->i2c_client = au0828_i2c_client_template;
382
383 dev->i2c_adap.dev.parent = &dev->usbdev->dev;
384
385 strlcpy(dev->i2c_adap.name, KBUILD_MODNAME,
386 sizeof(dev->i2c_adap.name));
387
388 dev->i2c_adap.algo = &dev->i2c_algo;
389 dev->i2c_adap.algo_data = dev;
390 #ifdef CONFIG_VIDEO_AU0828_V4L2
391 i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev);
392 #else
393 i2c_set_adapdata(&dev->i2c_adap, dev);
394 #endif
395 i2c_add_adapter(&dev->i2c_adap);
396
397 dev->i2c_client.adapter = &dev->i2c_adap;
398
399 if (0 == dev->i2c_rc) {
400 pr_info("i2c bus registered\n");
401 if (i2c_scan)
402 do_i2c_scan(KBUILD_MODNAME, &dev->i2c_client);
403 } else
404 pr_info("i2c bus register FAILED\n");
405
406 return dev->i2c_rc;
407 }
408
au0828_i2c_unregister(struct au0828_dev * dev)409 int au0828_i2c_unregister(struct au0828_dev *dev)
410 {
411 i2c_del_adapter(&dev->i2c_adap);
412 return 0;
413 }
414
415