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 <linux/module.h>
23 #include <linux/moduleparam.h>
24 #include <linux/init.h>
25 #include <linux/delay.h>
26 #include <linux/io.h>
27
28 #include "au0828.h"
29
30 #include <media/v4l2-common.h>
31
32 static int i2c_scan;
33 module_param(i2c_scan, int, 0444);
34 MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
35
36 #define I2C_WAIT_DELAY 512
37 #define I2C_WAIT_RETRY 64
38
i2c_slave_did_write_ack(struct i2c_adapter * i2c_adap)39 static inline int i2c_slave_did_write_ack(struct i2c_adapter *i2c_adap)
40 {
41 struct au0828_dev *dev = i2c_adap->algo_data;
42 return au0828_read(dev, REG_201) & 0x08 ? 0 : 1;
43 }
44
i2c_slave_did_read_ack(struct i2c_adapter * i2c_adap)45 static inline int i2c_slave_did_read_ack(struct i2c_adapter *i2c_adap)
46 {
47 struct au0828_dev *dev = i2c_adap->algo_data;
48 return au0828_read(dev, REG_201) & 0x02 ? 0 : 1;
49 }
50
i2c_wait_read_ack(struct i2c_adapter * i2c_adap)51 static int i2c_wait_read_ack(struct i2c_adapter *i2c_adap)
52 {
53 int count;
54
55 for (count = 0; count < I2C_WAIT_RETRY; count++) {
56 if (!i2c_slave_did_read_ack(i2c_adap))
57 break;
58 udelay(I2C_WAIT_DELAY);
59 }
60
61 if (I2C_WAIT_RETRY == count)
62 return 0;
63
64 return 1;
65 }
66
i2c_is_read_busy(struct i2c_adapter * i2c_adap)67 static inline int i2c_is_read_busy(struct i2c_adapter *i2c_adap)
68 {
69 struct au0828_dev *dev = i2c_adap->algo_data;
70 return au0828_read(dev, REG_201) & 0x01 ? 0 : 1;
71 }
72
i2c_wait_read_done(struct i2c_adapter * i2c_adap)73 static int i2c_wait_read_done(struct i2c_adapter *i2c_adap)
74 {
75 int count;
76
77 for (count = 0; count < I2C_WAIT_RETRY; count++) {
78 if (!i2c_is_read_busy(i2c_adap))
79 break;
80 udelay(I2C_WAIT_DELAY);
81 }
82
83 if (I2C_WAIT_RETRY == count)
84 return 0;
85
86 return 1;
87 }
88
i2c_is_write_done(struct i2c_adapter * i2c_adap)89 static inline int i2c_is_write_done(struct i2c_adapter *i2c_adap)
90 {
91 struct au0828_dev *dev = i2c_adap->algo_data;
92 return au0828_read(dev, REG_201) & 0x04 ? 1 : 0;
93 }
94
i2c_wait_write_done(struct i2c_adapter * i2c_adap)95 static int i2c_wait_write_done(struct i2c_adapter *i2c_adap)
96 {
97 int count;
98
99 for (count = 0; count < I2C_WAIT_RETRY; count++) {
100 if (i2c_is_write_done(i2c_adap))
101 break;
102 udelay(I2C_WAIT_DELAY);
103 }
104
105 if (I2C_WAIT_RETRY == count)
106 return 0;
107
108 return 1;
109 }
110
i2c_is_busy(struct i2c_adapter * i2c_adap)111 static inline int i2c_is_busy(struct i2c_adapter *i2c_adap)
112 {
113 struct au0828_dev *dev = i2c_adap->algo_data;
114 return au0828_read(dev, REG_201) & 0x10 ? 1 : 0;
115 }
116
i2c_wait_done(struct i2c_adapter * i2c_adap)117 static int i2c_wait_done(struct i2c_adapter *i2c_adap)
118 {
119 int count;
120
121 for (count = 0; count < I2C_WAIT_RETRY; count++) {
122 if (!i2c_is_busy(i2c_adap))
123 break;
124 udelay(I2C_WAIT_DELAY);
125 }
126
127 if (I2C_WAIT_RETRY == count)
128 return 0;
129
130 return 1;
131 }
132
133 /* FIXME: Implement join handling correctly */
i2c_sendbytes(struct i2c_adapter * i2c_adap,const struct i2c_msg * msg,int joined_rlen)134 static int i2c_sendbytes(struct i2c_adapter *i2c_adap,
135 const struct i2c_msg *msg, int joined_rlen)
136 {
137 int i, strobe = 0;
138 struct au0828_dev *dev = i2c_adap->algo_data;
139
140 dprintk(4, "%s()\n", __func__);
141
142 au0828_write(dev, REG_2FF, 0x01);
143 au0828_write(dev, REG_202, 0x07);
144
145 /* Hardware needs 8 bit addresses */
146 au0828_write(dev, REG_203, msg->addr << 1);
147
148 dprintk(4, "SEND: %02x\n", msg->addr);
149
150 for (i = 0; i < msg->len;) {
151
152 dprintk(4, " %02x\n", msg->buf[i]);
153
154 au0828_write(dev, REG_205, msg->buf[i]);
155
156 strobe++;
157 i++;
158
159 if ((strobe >= 4) || (i >= msg->len)) {
160
161 /* Strobe the byte into the bus */
162 if (i < msg->len)
163 au0828_write(dev, REG_200, 0x41);
164 else
165 au0828_write(dev, REG_200, 0x01);
166
167 /* Reset strobe trigger */
168 strobe = 0;
169
170 if (!i2c_wait_write_done(i2c_adap))
171 return -EIO;
172
173 }
174
175 }
176 if (!i2c_wait_done(i2c_adap))
177 return -EIO;
178
179 dprintk(4, "\n");
180
181 return msg->len;
182 }
183
184 /* FIXME: Implement join handling correctly */
i2c_readbytes(struct i2c_adapter * i2c_adap,const struct i2c_msg * msg,int joined)185 static int i2c_readbytes(struct i2c_adapter *i2c_adap,
186 const struct i2c_msg *msg, int joined)
187 {
188 struct au0828_dev *dev = i2c_adap->algo_data;
189 int i;
190
191 dprintk(4, "%s()\n", __func__);
192
193 au0828_write(dev, REG_2FF, 0x01);
194 au0828_write(dev, REG_202, 0x07);
195
196 /* Hardware needs 8 bit addresses */
197 au0828_write(dev, REG_203, msg->addr << 1);
198
199 dprintk(4, " RECV:\n");
200
201 /* Deal with i2c_scan */
202 if (msg->len == 0) {
203 au0828_write(dev, REG_200, 0x20);
204 if (i2c_wait_read_ack(i2c_adap))
205 return -EIO;
206 return 0;
207 }
208
209 for (i = 0; i < msg->len;) {
210
211 i++;
212
213 if (i < msg->len)
214 au0828_write(dev, REG_200, 0x60);
215 else
216 au0828_write(dev, REG_200, 0x20);
217
218 if (!i2c_wait_read_done(i2c_adap))
219 return -EIO;
220
221 msg->buf[i-1] = au0828_read(dev, REG_209) & 0xff;
222
223 dprintk(4, " %02x\n", msg->buf[i-1]);
224 }
225 if (!i2c_wait_done(i2c_adap))
226 return -EIO;
227
228 dprintk(4, "\n");
229
230 return msg->len;
231 }
232
i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg * msgs,int num)233 static int i2c_xfer(struct i2c_adapter *i2c_adap,
234 struct i2c_msg *msgs, int num)
235 {
236 int i, retval = 0;
237
238 dprintk(4, "%s(num = %d)\n", __func__, num);
239
240 for (i = 0; i < num; i++) {
241 dprintk(4, "%s(num = %d) addr = 0x%02x len = 0x%x\n",
242 __func__, num, msgs[i].addr, msgs[i].len);
243 if (msgs[i].flags & I2C_M_RD) {
244 /* read */
245 retval = i2c_readbytes(i2c_adap, &msgs[i], 0);
246 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
247 msgs[i].addr == msgs[i + 1].addr) {
248 /* write then read from same address */
249 retval = i2c_sendbytes(i2c_adap, &msgs[i],
250 msgs[i + 1].len);
251 if (retval < 0)
252 goto err;
253 i++;
254 retval = i2c_readbytes(i2c_adap, &msgs[i], 1);
255 } else {
256 /* write */
257 retval = i2c_sendbytes(i2c_adap, &msgs[i], 0);
258 }
259 if (retval < 0)
260 goto err;
261 }
262 return num;
263
264 err:
265 return retval;
266 }
267
attach_inform(struct i2c_client * client)268 static int attach_inform(struct i2c_client *client)
269 {
270 dprintk(1, "%s i2c attach [addr=0x%x,client=%s]\n",
271 client->driver->driver.name, client->addr, client->name);
272
273 if (!client->driver->command)
274 return 0;
275
276 return 0;
277 }
278
detach_inform(struct i2c_client * client)279 static int detach_inform(struct i2c_client *client)
280 {
281 dprintk(1, "i2c detach [client=%s]\n", client->name);
282
283 return 0;
284 }
285
au0828_call_i2c_clients(struct au0828_dev * dev,unsigned int cmd,void * arg)286 void au0828_call_i2c_clients(struct au0828_dev *dev,
287 unsigned int cmd, void *arg)
288 {
289 if (dev->i2c_rc != 0)
290 return;
291
292 i2c_clients_command(&dev->i2c_adap, cmd, arg);
293 }
294
au0828_functionality(struct i2c_adapter * adap)295 static u32 au0828_functionality(struct i2c_adapter *adap)
296 {
297 return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
298 }
299
300 static struct i2c_algorithm au0828_i2c_algo_template = {
301 .master_xfer = i2c_xfer,
302 .functionality = au0828_functionality,
303 };
304
305 /* ----------------------------------------------------------------------- */
306
307 static struct i2c_adapter au0828_i2c_adap_template = {
308 .name = DRIVER_NAME,
309 .owner = THIS_MODULE,
310 .id = I2C_HW_B_AU0828,
311 .algo = &au0828_i2c_algo_template,
312 .class = I2C_CLASS_TV_ANALOG,
313 .client_register = attach_inform,
314 .client_unregister = detach_inform,
315 };
316
317 static struct i2c_client au0828_i2c_client_template = {
318 .name = "au0828 internal",
319 };
320
321 static char *i2c_devs[128] = {
322 [0x8e >> 1] = "au8522",
323 [0xa0 >> 1] = "eeprom",
324 [0xc2 >> 1] = "tuner/xc5000",
325 };
326
do_i2c_scan(char * name,struct i2c_client * c)327 static void do_i2c_scan(char *name, struct i2c_client *c)
328 {
329 unsigned char buf;
330 int i, rc;
331
332 for (i = 0; i < 128; i++) {
333 c->addr = i;
334 rc = i2c_master_recv(c, &buf, 0);
335 if (rc < 0)
336 continue;
337 printk(KERN_INFO "%s: i2c scan: found device @ 0x%x [%s]\n",
338 name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
339 }
340 }
341
342 /* init + register i2c algo-bit adapter */
au0828_i2c_register(struct au0828_dev * dev)343 int au0828_i2c_register(struct au0828_dev *dev)
344 {
345 dprintk(1, "%s()\n", __func__);
346
347 memcpy(&dev->i2c_adap, &au0828_i2c_adap_template,
348 sizeof(dev->i2c_adap));
349 memcpy(&dev->i2c_algo, &au0828_i2c_algo_template,
350 sizeof(dev->i2c_algo));
351 memcpy(&dev->i2c_client, &au0828_i2c_client_template,
352 sizeof(dev->i2c_client));
353
354 dev->i2c_adap.dev.parent = &dev->usbdev->dev;
355
356 strlcpy(dev->i2c_adap.name, DRIVER_NAME,
357 sizeof(dev->i2c_adap.name));
358
359 dev->i2c_algo.data = dev;
360 dev->i2c_adap.algo_data = dev;
361 i2c_set_adapdata(&dev->i2c_adap, dev);
362 i2c_add_adapter(&dev->i2c_adap);
363
364 dev->i2c_client.adapter = &dev->i2c_adap;
365
366 if (0 == dev->i2c_rc) {
367 printk(KERN_INFO "%s: i2c bus registered\n", DRIVER_NAME);
368 if (i2c_scan)
369 do_i2c_scan(DRIVER_NAME, &dev->i2c_client);
370 } else
371 printk(KERN_INFO "%s: i2c bus register FAILED\n", DRIVER_NAME);
372
373 return dev->i2c_rc;
374 }
375
au0828_i2c_unregister(struct au0828_dev * dev)376 int au0828_i2c_unregister(struct au0828_dev *dev)
377 {
378 i2c_del_adapter(&dev->i2c_adap);
379 return 0;
380 }
381
382