1 /*
2 *
3 * device driver for philips saa7134 based TV cards
4 * i2c interface support
5 *
6 * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 */
22
23 #include <linux/init.h>
24 #include <linux/list.h>
25 #include <linux/module.h>
26 #include <linux/kernel.h>
27 #include <linux/slab.h>
28 #include <linux/delay.h>
29
30 #include "saa7134-reg.h"
31 #include "saa7134.h"
32 #include <media/v4l2-common.h>
33
34 /* ----------------------------------------------------------- */
35
36 static unsigned int i2c_debug;
37 module_param(i2c_debug, int, 0644);
38 MODULE_PARM_DESC(i2c_debug,"enable debug messages [i2c]");
39
40 static unsigned int i2c_scan;
41 module_param(i2c_scan, int, 0444);
42 MODULE_PARM_DESC(i2c_scan,"scan i2c bus at insmod time");
43
44 #define d1printk if (1 == i2c_debug) printk
45 #define d2printk if (2 == i2c_debug) printk
46
47 #define I2C_WAIT_DELAY 32
48 #define I2C_WAIT_RETRY 16
49
50 /* ----------------------------------------------------------- */
51
52 static char *str_i2c_status[] = {
53 "IDLE", "DONE_STOP", "BUSY", "TO_SCL", "TO_ARB", "DONE_WRITE",
54 "DONE_READ", "DONE_WRITE_TO", "DONE_READ_TO", "NO_DEVICE",
55 "NO_ACKN", "BUS_ERR", "ARB_LOST", "SEQ_ERR", "ST_ERR", "SW_ERR"
56 };
57
58 enum i2c_status {
59 IDLE = 0, // no I2C command pending
60 DONE_STOP = 1, // I2C command done and STOP executed
61 BUSY = 2, // executing I2C command
62 TO_SCL = 3, // executing I2C command, time out on clock stretching
63 TO_ARB = 4, // time out on arbitration trial, still trying
64 DONE_WRITE = 5, // I2C command done and awaiting next write command
65 DONE_READ = 6, // I2C command done and awaiting next read command
66 DONE_WRITE_TO = 7, // see 5, and time out on status echo
67 DONE_READ_TO = 8, // see 6, and time out on status echo
68 NO_DEVICE = 9, // no acknowledge on device slave address
69 NO_ACKN = 10, // no acknowledge after data byte transfer
70 BUS_ERR = 11, // bus error
71 ARB_LOST = 12, // arbitration lost during transfer
72 SEQ_ERR = 13, // erroneous programming sequence
73 ST_ERR = 14, // wrong status echoing
74 SW_ERR = 15 // software error
75 };
76
77 static char *str_i2c_attr[] = {
78 "NOP", "STOP", "CONTINUE", "START"
79 };
80
81 enum i2c_attr {
82 NOP = 0, // no operation on I2C bus
83 STOP = 1, // stop condition, no associated byte transfer
84 CONTINUE = 2, // continue with byte transfer
85 START = 3 // start condition with byte transfer
86 };
87
88 static inline enum i2c_status i2c_get_status(struct saa7134_dev *dev)
89 {
90 enum i2c_status status;
91
92 status = saa_readb(SAA7134_I2C_ATTR_STATUS) & 0x0f;
93 d2printk(KERN_DEBUG "%s: i2c stat <= %s\n",dev->name,
94 str_i2c_status[status]);
95 return status;
96 }
97
98 static inline void i2c_set_status(struct saa7134_dev *dev,
99 enum i2c_status status)
100 {
101 d2printk(KERN_DEBUG "%s: i2c stat => %s\n",dev->name,
102 str_i2c_status[status]);
103 saa_andorb(SAA7134_I2C_ATTR_STATUS,0x0f,status);
104 }
105
106 static inline void i2c_set_attr(struct saa7134_dev *dev, enum i2c_attr attr)
107 {
108 d2printk(KERN_DEBUG "%s: i2c attr => %s\n",dev->name,
109 str_i2c_attr[attr]);
110 saa_andorb(SAA7134_I2C_ATTR_STATUS,0xc0,attr << 6);
111 }
112
113 static inline int i2c_is_error(enum i2c_status status)
114 {
115 switch (status) {
116 case NO_DEVICE:
117 case NO_ACKN:
118 case BUS_ERR:
119 case ARB_LOST:
120 case SEQ_ERR:
121 case ST_ERR:
122 return true;
123 default:
124 return false;
125 }
126 }
127
128 static inline int i2c_is_idle(enum i2c_status status)
129 {
130 switch (status) {
131 case IDLE:
132 case DONE_STOP:
133 return true;
134 default:
135 return false;
136 }
137 }
138
139 static inline int i2c_is_busy(enum i2c_status status)
140 {
141 switch (status) {
142 case BUSY:
143 case TO_SCL:
144 case TO_ARB:
145 return true;
146 default:
147 return false;
148 }
149 }
150
151 static int i2c_is_busy_wait(struct saa7134_dev *dev)
152 {
153 enum i2c_status status;
154 int count;
155
156 for (count = 0; count < I2C_WAIT_RETRY; count++) {
157 status = i2c_get_status(dev);
158 if (!i2c_is_busy(status))
159 break;
160 saa_wait(I2C_WAIT_DELAY);
161 }
162 if (I2C_WAIT_RETRY == count)
163 return false;
164 return true;
165 }
166
167 static int i2c_reset(struct saa7134_dev *dev)
168 {
169 enum i2c_status status;
170 int count;
171
172 d2printk(KERN_DEBUG "%s: i2c reset\n",dev->name);
173 status = i2c_get_status(dev);
174 if (!i2c_is_error(status))
175 return true;
176 i2c_set_status(dev,status);
177
178 for (count = 0; count < I2C_WAIT_RETRY; count++) {
179 status = i2c_get_status(dev);
180 if (!i2c_is_error(status))
181 break;
182 udelay(I2C_WAIT_DELAY);
183 }
184 if (I2C_WAIT_RETRY == count)
185 return false;
186
187 if (!i2c_is_idle(status))
188 return false;
189
190 i2c_set_attr(dev,NOP);
191 return true;
192 }
193
194 static inline int i2c_send_byte(struct saa7134_dev *dev,
195 enum i2c_attr attr,
196 unsigned char data)
197 {
198 enum i2c_status status;
199 __u32 dword;
200
201 /* have to write both attr + data in one 32bit word */
202 dword = saa_readl(SAA7134_I2C_ATTR_STATUS >> 2);
203 dword &= 0x0f;
204 dword |= (attr << 6);
205 dword |= ((__u32)data << 8);
206 dword |= 0x00 << 16; /* 100 kHz */
207 // dword |= 0x40 << 16; /* 400 kHz */
208 dword |= 0xf0 << 24;
209 saa_writel(SAA7134_I2C_ATTR_STATUS >> 2, dword);
210 d2printk(KERN_DEBUG "%s: i2c data => 0x%x\n",dev->name,data);
211
212 if (!i2c_is_busy_wait(dev))
213 return -EIO;
214 status = i2c_get_status(dev);
215 if (i2c_is_error(status))
216 return -EIO;
217 return 0;
218 }
219
220 static inline int i2c_recv_byte(struct saa7134_dev *dev)
221 {
222 enum i2c_status status;
223 unsigned char data;
224
225 i2c_set_attr(dev,CONTINUE);
226 if (!i2c_is_busy_wait(dev))
227 return -EIO;
228 status = i2c_get_status(dev);
229 if (i2c_is_error(status))
230 return -EIO;
231 data = saa_readb(SAA7134_I2C_DATA);
232 d2printk(KERN_DEBUG "%s: i2c data <= 0x%x\n",dev->name,data);
233 return data;
234 }
235
236 static int saa7134_i2c_xfer(struct i2c_adapter *i2c_adap,
237 struct i2c_msg *msgs, int num)
238 {
239 struct saa7134_dev *dev = i2c_adap->algo_data;
240 enum i2c_status status;
241 unsigned char data;
242 int addr,rc,i,byte;
243
244 status = i2c_get_status(dev);
245 if (!i2c_is_idle(status))
246 if (!i2c_reset(dev))
247 return -EIO;
248
249 d2printk("start xfer\n");
250 d1printk(KERN_DEBUG "%s: i2c xfer:",dev->name);
251 for (i = 0; i < num; i++) {
252 if (!(msgs[i].flags & I2C_M_NOSTART) || 0 == i) {
253 /* send address */
254 d2printk("send address\n");
255 addr = msgs[i].addr << 1;
256 if (msgs[i].flags & I2C_M_RD)
257 addr |= 1;
258 if (i > 0 && msgs[i].flags & I2C_M_RD && msgs[i].addr != 0x40) {
259 /* workaround for a saa7134 i2c bug
260 * needed to talk to the mt352 demux
261 * thanks to pinnacle for the hint */
262 int quirk = 0xfe;
263 d1printk(" [%02x quirk]",quirk);
264 i2c_send_byte(dev,START,quirk);
265 i2c_recv_byte(dev);
266 }
267 d1printk(" < %02x", addr);
268 rc = i2c_send_byte(dev,START,addr);
269 if (rc < 0)
270 goto err;
271 }
272 if (msgs[i].flags & I2C_M_RD) {
273 /* read bytes */
274 d2printk("read bytes\n");
275 for (byte = 0; byte < msgs[i].len; byte++) {
276 d1printk(" =");
277 rc = i2c_recv_byte(dev);
278 if (rc < 0)
279 goto err;
280 d1printk("%02x", rc);
281 msgs[i].buf[byte] = rc;
282 }
283 } else {
284 /* write bytes */
285 d2printk("write bytes\n");
286 for (byte = 0; byte < msgs[i].len; byte++) {
287 data = msgs[i].buf[byte];
288 d1printk(" %02x", data);
289 rc = i2c_send_byte(dev,CONTINUE,data);
290 if (rc < 0)
291 goto err;
292 }
293 }
294 }
295 d2printk("xfer done\n");
296 d1printk(" >");
297 i2c_set_attr(dev,STOP);
298 rc = -EIO;
299 if (!i2c_is_busy_wait(dev))
300 goto err;
301 status = i2c_get_status(dev);
302 if (i2c_is_error(status))
303 goto err;
304 /* ensure that the bus is idle for at least one bit slot */
305 msleep(1);
306
307 d1printk("\n");
308 return num;
309 err:
310 if (1 == i2c_debug) {
311 status = i2c_get_status(dev);
312 printk(" ERROR: %s\n",str_i2c_status[status]);
313 }
314 return rc;
315 }
316
317 /* ----------------------------------------------------------- */
318
319 static u32 functionality(struct i2c_adapter *adap)
320 {
321 return I2C_FUNC_SMBUS_EMUL;
322 }
323
324 static struct i2c_algorithm saa7134_algo = {
325 .master_xfer = saa7134_i2c_xfer,
326 .functionality = functionality,
327 };
328
329 static struct i2c_adapter saa7134_adap_template = {
330 .owner = THIS_MODULE,
331 .name = "saa7134",
332 .id = I2C_HW_SAA7134,
333 .algo = &saa7134_algo,
334 };
335
336 static struct i2c_client saa7134_client_template = {
337 .name = "saa7134 internal",
338 };
339
340 /* ----------------------------------------------------------- */
341
342 static int
343 saa7134_i2c_eeprom(struct saa7134_dev *dev, unsigned char *eedata, int len)
344 {
345 unsigned char buf;
346 int i,err;
347
348 dev->i2c_client.addr = 0xa0 >> 1;
349 buf = 0;
350 if (1 != (err = i2c_master_send(&dev->i2c_client,&buf,1))) {
351 printk(KERN_INFO "%s: Huh, no eeprom present (err=%d)?\n",
352 dev->name,err);
353 return -1;
354 }
355 if (len != (err = i2c_master_recv(&dev->i2c_client,eedata,len))) {
356 printk(KERN_WARNING "%s: i2c eeprom read error (err=%d)\n",
357 dev->name,err);
358 return -1;
359 }
360 for (i = 0; i < len; i++) {
361 if (0 == (i % 16))
362 printk(KERN_INFO "%s: i2c eeprom %02x:",dev->name,i);
363 printk(" %02x",eedata[i]);
364 if (15 == (i % 16))
365 printk("\n");
366 }
367 return 0;
368 }
369
370 static char *i2c_devs[128] = {
371 [ 0x20 ] = "mpeg encoder (saa6752hs)",
372 [ 0xa0 >> 1 ] = "eeprom",
373 [ 0xc0 >> 1 ] = "tuner (analog)",
374 [ 0x86 >> 1 ] = "tda9887",
375 [ 0x5a >> 1 ] = "remote control",
376 };
377
378 static void do_i2c_scan(char *name, struct i2c_client *c)
379 {
380 unsigned char buf;
381 int i,rc;
382
383 for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
384 c->addr = i;
385 rc = i2c_master_recv(c,&buf,0);
386 if (rc < 0)
387 continue;
388 printk("%s: i2c scan: found device @ 0x%x [%s]\n",
389 name, i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
390 }
391 }
392
393 int saa7134_i2c_register(struct saa7134_dev *dev)
394 {
395 dev->i2c_adap = saa7134_adap_template;
396 dev->i2c_adap.dev.parent = &dev->pci->dev;
397 strcpy(dev->i2c_adap.name,dev->name);
398 dev->i2c_adap.algo_data = dev;
399 i2c_set_adapdata(&dev->i2c_adap, &dev->v4l2_dev);
400 i2c_add_adapter(&dev->i2c_adap);
401
402 dev->i2c_client = saa7134_client_template;
403 dev->i2c_client.adapter = &dev->i2c_adap;
404
405 saa7134_i2c_eeprom(dev,dev->eedata,sizeof(dev->eedata));
406 if (i2c_scan)
407 do_i2c_scan(dev->name,&dev->i2c_client);
408
409 /* Instantiate the IR receiver device, if present */
410 saa7134_probe_i2c_ir(dev);
411 return 0;
412 }
413
414 int saa7134_i2c_unregister(struct saa7134_dev *dev)
415 {
416 i2c_del_adapter(&dev->i2c_adap);
417 return 0;
418 }
419
420 /* ----------------------------------------------------------- */
421 /*
422 * Local variables:
423 * c-basic-offset: 8
424 * End:
425 */
426
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