1 #include <linux/i2c.h>
2 #include <linux/mutex.h>
3 #include <linux/module.h>
4 
5 #include "dibx000_common.h"
6 
7 static int debug;
8 module_param(debug, int, 0644);
9 MODULE_PARM_DESC(debug, "turn on debugging (default: 0)");
10 
11 #define dprintk(args...) do { if (debug) { printk(KERN_DEBUG "DiBX000: "); printk(args); printk("\n"); } } while (0)
12 
13 static int dibx000_write_word(struct dibx000_i2c_master *mst, u16 reg, u16 val)
14 {
15 	int ret;
16 
17 	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
18 		dprintk("could not acquire lock");
19 		return -EINVAL;
20 	}
21 
22 	mst->i2c_write_buffer[0] = (reg >> 8) & 0xff;
23 	mst->i2c_write_buffer[1] = reg & 0xff;
24 	mst->i2c_write_buffer[2] = (val >> 8) & 0xff;
25 	mst->i2c_write_buffer[3] = val & 0xff;
26 
27 	memset(mst->msg, 0, sizeof(struct i2c_msg));
28 	mst->msg[0].addr = mst->i2c_addr;
29 	mst->msg[0].flags = 0;
30 	mst->msg[0].buf = mst->i2c_write_buffer;
31 	mst->msg[0].len = 4;
32 
33 	ret = i2c_transfer(mst->i2c_adap, mst->msg, 1) != 1 ? -EREMOTEIO : 0;
34 	mutex_unlock(&mst->i2c_buffer_lock);
35 
36 	return ret;
37 }
38 
39 static u16 dibx000_read_word(struct dibx000_i2c_master *mst, u16 reg)
40 {
41 	u16 ret;
42 
43 	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
44 		dprintk("could not acquire lock");
45 		return 0;
46 	}
47 
48 	mst->i2c_write_buffer[0] = reg >> 8;
49 	mst->i2c_write_buffer[1] = reg & 0xff;
50 
51 	memset(mst->msg, 0, 2 * sizeof(struct i2c_msg));
52 	mst->msg[0].addr = mst->i2c_addr;
53 	mst->msg[0].flags = 0;
54 	mst->msg[0].buf = mst->i2c_write_buffer;
55 	mst->msg[0].len = 2;
56 	mst->msg[1].addr = mst->i2c_addr;
57 	mst->msg[1].flags = I2C_M_RD;
58 	mst->msg[1].buf = mst->i2c_read_buffer;
59 	mst->msg[1].len = 2;
60 
61 	if (i2c_transfer(mst->i2c_adap, mst->msg, 2) != 2)
62 		dprintk("i2c read error on %d", reg);
63 
64 	ret = (mst->i2c_read_buffer[0] << 8) | mst->i2c_read_buffer[1];
65 	mutex_unlock(&mst->i2c_buffer_lock);
66 
67 	return ret;
68 }
69 
70 static int dibx000_is_i2c_done(struct dibx000_i2c_master *mst)
71 {
72 	int i = 100;
73 	u16 status;
74 
75 	while (((status = dibx000_read_word(mst, mst->base_reg + 2)) & 0x0100) == 0 && --i > 0)
76 		;
77 
78 	/* i2c timed out */
79 	if (i == 0)
80 		return -EREMOTEIO;
81 
82 	/* no acknowledge */
83 	if ((status & 0x0080) == 0)
84 		return -EREMOTEIO;
85 
86 	return 0;
87 }
88 
89 static int dibx000_master_i2c_write(struct dibx000_i2c_master *mst, struct i2c_msg *msg, u8 stop)
90 {
91 	u16 data;
92 	u16 da;
93 	u16 i;
94 	u16 txlen = msg->len, len;
95 	const u8 *b = msg->buf;
96 
97 	while (txlen) {
98 		dibx000_read_word(mst, mst->base_reg + 2);
99 
100 		len = txlen > 8 ? 8 : txlen;
101 		for (i = 0; i < len; i += 2) {
102 			data = *b++ << 8;
103 			if (i+1 < len)
104 				data |= *b++;
105 			dibx000_write_word(mst, mst->base_reg, data);
106 		}
107 		da = (((u8) (msg->addr))  << 9) |
108 			(1           << 8) |
109 			(1           << 7) |
110 			(0           << 6) |
111 			(0           << 5) |
112 			((len & 0x7) << 2) |
113 			(0           << 1) |
114 			(0           << 0);
115 
116 		if (txlen == msg->len)
117 			da |= 1 << 5; /* start */
118 
119 		if (txlen-len == 0 && stop)
120 			da |= 1 << 6; /* stop */
121 
122 		dibx000_write_word(mst, mst->base_reg+1, da);
123 
124 		if (dibx000_is_i2c_done(mst) != 0)
125 			return -EREMOTEIO;
126 		txlen -= len;
127 	}
128 
129 	return 0;
130 }
131 
132 static int dibx000_master_i2c_read(struct dibx000_i2c_master *mst, struct i2c_msg *msg)
133 {
134 	u16 da;
135 	u8 *b = msg->buf;
136 	u16 rxlen = msg->len, len;
137 
138 	while (rxlen) {
139 		len = rxlen > 8 ? 8 : rxlen;
140 		da = (((u8) (msg->addr)) << 9) |
141 			(1           << 8) |
142 			(1           << 7) |
143 			(0           << 6) |
144 			(0           << 5) |
145 			((len & 0x7) << 2) |
146 			(1           << 1) |
147 			(0           << 0);
148 
149 		if (rxlen == msg->len)
150 			da |= 1 << 5; /* start */
151 
152 		if (rxlen-len == 0)
153 			da |= 1 << 6; /* stop */
154 		dibx000_write_word(mst, mst->base_reg+1, da);
155 
156 		if (dibx000_is_i2c_done(mst) != 0)
157 			return -EREMOTEIO;
158 
159 		rxlen -= len;
160 
161 		while (len) {
162 			da = dibx000_read_word(mst, mst->base_reg);
163 			*b++ = (da >> 8) & 0xff;
164 			len--;
165 			if (len >= 1) {
166 				*b++ =  da   & 0xff;
167 				len--;
168 			}
169 		}
170 	}
171 
172 	return 0;
173 }
174 
175 int dibx000_i2c_set_speed(struct i2c_adapter *i2c_adap, u16 speed)
176 {
177 	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
178 
179 	if (mst->device_rev < DIB7000MC && speed < 235)
180 		speed = 235;
181 	return dibx000_write_word(mst, mst->base_reg + 3, (u16)(60000 / speed));
182 
183 }
184 EXPORT_SYMBOL(dibx000_i2c_set_speed);
185 
186 static u32 dibx000_i2c_func(struct i2c_adapter *adapter)
187 {
188 	return I2C_FUNC_I2C;
189 }
190 
191 static int dibx000_i2c_select_interface(struct dibx000_i2c_master *mst,
192 					enum dibx000_i2c_interface intf)
193 {
194 	if (mst->device_rev > DIB3000MC && mst->selected_interface != intf) {
195 		dprintk("selecting interface: %d", intf);
196 		mst->selected_interface = intf;
197 		return dibx000_write_word(mst, mst->base_reg + 4, intf);
198 	}
199 	return 0;
200 }
201 
202 static int dibx000_i2c_master_xfer_gpio12(struct i2c_adapter *i2c_adap, struct i2c_msg msg[], int num)
203 {
204 	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
205 	int msg_index;
206 	int ret = 0;
207 
208 	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_1_2);
209 	for (msg_index = 0; msg_index < num; msg_index++) {
210 		if (msg[msg_index].flags & I2C_M_RD) {
211 			ret = dibx000_master_i2c_read(mst, &msg[msg_index]);
212 			if (ret != 0)
213 				return 0;
214 		} else {
215 			ret = dibx000_master_i2c_write(mst, &msg[msg_index], 1);
216 			if (ret != 0)
217 				return 0;
218 		}
219 	}
220 
221 	return num;
222 }
223 
224 static int dibx000_i2c_master_xfer_gpio34(struct i2c_adapter *i2c_adap, struct i2c_msg msg[], int num)
225 {
226 	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
227 	int msg_index;
228 	int ret = 0;
229 
230 	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_3_4);
231 	for (msg_index = 0; msg_index < num; msg_index++) {
232 		if (msg[msg_index].flags & I2C_M_RD) {
233 			ret = dibx000_master_i2c_read(mst, &msg[msg_index]);
234 			if (ret != 0)
235 				return 0;
236 		} else {
237 			ret = dibx000_master_i2c_write(mst, &msg[msg_index], 1);
238 			if (ret != 0)
239 				return 0;
240 		}
241 	}
242 
243 	return num;
244 }
245 
246 static struct i2c_algorithm dibx000_i2c_master_gpio12_xfer_algo = {
247 	.master_xfer = dibx000_i2c_master_xfer_gpio12,
248 	.functionality = dibx000_i2c_func,
249 };
250 
251 static struct i2c_algorithm dibx000_i2c_master_gpio34_xfer_algo = {
252 	.master_xfer = dibx000_i2c_master_xfer_gpio34,
253 	.functionality = dibx000_i2c_func,
254 };
255 
256 static int dibx000_i2c_gate_ctrl(struct dibx000_i2c_master *mst, u8 tx[4],
257 				 u8 addr, int onoff)
258 {
259 	u16 val;
260 
261 
262 	if (onoff)
263 		val = addr << 8;	// bit 7 = use master or not, if 0, the gate is open
264 	else
265 		val = 1 << 7;
266 
267 	if (mst->device_rev > DIB7000)
268 		val <<= 1;
269 
270 	tx[0] = (((mst->base_reg + 1) >> 8) & 0xff);
271 	tx[1] = ((mst->base_reg + 1) & 0xff);
272 	tx[2] = val >> 8;
273 	tx[3] = val & 0xff;
274 
275 	return 0;
276 }
277 
278 static int dibx000_i2c_gated_gpio67_xfer(struct i2c_adapter *i2c_adap,
279 					struct i2c_msg msg[], int num)
280 {
281 	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
282 	int ret;
283 
284 	if (num > 32) {
285 		dprintk("%s: too much I2C message to be transmitted (%i).\
286 				Maximum is 32", __func__, num);
287 		return -ENOMEM;
288 	}
289 
290 	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_6_7);
291 
292 	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
293 		dprintk("could not acquire lock");
294 		return -EINVAL;
295 	}
296 
297 	memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));
298 
299 	/* open the gate */
300 	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
301 	mst->msg[0].addr = mst->i2c_addr;
302 	mst->msg[0].buf = &mst->i2c_write_buffer[0];
303 	mst->msg[0].len = 4;
304 
305 	memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);
306 
307 	/* close the gate */
308 	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
309 	mst->msg[num + 1].addr = mst->i2c_addr;
310 	mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
311 	mst->msg[num + 1].len = 4;
312 
313 	ret = (i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ?
314 			num : -EIO);
315 
316 	mutex_unlock(&mst->i2c_buffer_lock);
317 	return ret;
318 }
319 
320 static struct i2c_algorithm dibx000_i2c_gated_gpio67_algo = {
321 	.master_xfer = dibx000_i2c_gated_gpio67_xfer,
322 	.functionality = dibx000_i2c_func,
323 };
324 
325 static int dibx000_i2c_gated_tuner_xfer(struct i2c_adapter *i2c_adap,
326 					struct i2c_msg msg[], int num)
327 {
328 	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
329 	int ret;
330 
331 	if (num > 32) {
332 		dprintk("%s: too much I2C message to be transmitted (%i).\
333 				Maximum is 32", __func__, num);
334 		return -ENOMEM;
335 	}
336 
337 	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);
338 
339 	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
340 		dprintk("could not acquire lock");
341 		return -EINVAL;
342 	}
343 	memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));
344 
345 	/* open the gate */
346 	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
347 	mst->msg[0].addr = mst->i2c_addr;
348 	mst->msg[0].buf = &mst->i2c_write_buffer[0];
349 	mst->msg[0].len = 4;
350 
351 	memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);
352 
353 	/* close the gate */
354 	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
355 	mst->msg[num + 1].addr = mst->i2c_addr;
356 	mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
357 	mst->msg[num + 1].len = 4;
358 
359 	ret = (i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ?
360 			num : -EIO);
361 	mutex_unlock(&mst->i2c_buffer_lock);
362 	return ret;
363 }
364 
365 static struct i2c_algorithm dibx000_i2c_gated_tuner_algo = {
366 	.master_xfer = dibx000_i2c_gated_tuner_xfer,
367 	.functionality = dibx000_i2c_func,
368 };
369 
370 struct i2c_adapter *dibx000_get_i2c_adapter(struct dibx000_i2c_master *mst,
371 						enum dibx000_i2c_interface intf,
372 						int gating)
373 {
374 	struct i2c_adapter *i2c = NULL;
375 
376 	switch (intf) {
377 	case DIBX000_I2C_INTERFACE_TUNER:
378 		if (gating)
379 			i2c = &mst->gated_tuner_i2c_adap;
380 		break;
381 	case DIBX000_I2C_INTERFACE_GPIO_1_2:
382 		if (!gating)
383 			i2c = &mst->master_i2c_adap_gpio12;
384 		break;
385 	case DIBX000_I2C_INTERFACE_GPIO_3_4:
386 		if (!gating)
387 			i2c = &mst->master_i2c_adap_gpio34;
388 		break;
389 	case DIBX000_I2C_INTERFACE_GPIO_6_7:
390 		if (gating)
391 			i2c = &mst->master_i2c_adap_gpio67;
392 		break;
393 	default:
394 		printk(KERN_ERR "DiBX000: incorrect I2C interface selected\n");
395 		break;
396 	}
397 
398 	return i2c;
399 }
400 
401 EXPORT_SYMBOL(dibx000_get_i2c_adapter);
402 
403 void dibx000_reset_i2c_master(struct dibx000_i2c_master *mst)
404 {
405 	/* initialize the i2c-master by closing the gate */
406 	u8 tx[4];
407 	struct i2c_msg m = {.addr = mst->i2c_addr,.buf = tx,.len = 4 };
408 
409 	dibx000_i2c_gate_ctrl(mst, tx, 0, 0);
410 	i2c_transfer(mst->i2c_adap, &m, 1);
411 	mst->selected_interface = 0xff;	// the first time force a select of the I2C
412 	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);
413 }
414 
415 EXPORT_SYMBOL(dibx000_reset_i2c_master);
416 
417 static int i2c_adapter_init(struct i2c_adapter *i2c_adap,
418 				struct i2c_algorithm *algo, const char *name,
419 				struct dibx000_i2c_master *mst)
420 {
421 	strncpy(i2c_adap->name, name, sizeof(i2c_adap->name));
422 	i2c_adap->algo = algo;
423 	i2c_adap->algo_data = NULL;
424 	i2c_set_adapdata(i2c_adap, mst);
425 	if (i2c_add_adapter(i2c_adap) < 0)
426 		return -ENODEV;
427 	return 0;
428 }
429 
430 int dibx000_init_i2c_master(struct dibx000_i2c_master *mst, u16 device_rev,
431 				struct i2c_adapter *i2c_adap, u8 i2c_addr)
432 {
433 	int ret;
434 
435 	mutex_init(&mst->i2c_buffer_lock);
436 	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
437 		dprintk("could not acquire lock");
438 		return -EINVAL;
439 	}
440 	memset(mst->msg, 0, sizeof(struct i2c_msg));
441 	mst->msg[0].addr = i2c_addr >> 1;
442 	mst->msg[0].flags = 0;
443 	mst->msg[0].buf = mst->i2c_write_buffer;
444 	mst->msg[0].len = 4;
445 
446 	mst->device_rev = device_rev;
447 	mst->i2c_adap = i2c_adap;
448 	mst->i2c_addr = i2c_addr >> 1;
449 
450 	if (device_rev == DIB7000P || device_rev == DIB8000)
451 		mst->base_reg = 1024;
452 	else
453 		mst->base_reg = 768;
454 
455 	mst->gated_tuner_i2c_adap.dev.parent = mst->i2c_adap->dev.parent;
456 	if (i2c_adapter_init
457 			(&mst->gated_tuner_i2c_adap, &dibx000_i2c_gated_tuner_algo,
458 			 "DiBX000 tuner I2C bus", mst) != 0)
459 		printk(KERN_ERR
460 				"DiBX000: could not initialize the tuner i2c_adapter\n");
461 
462 	mst->master_i2c_adap_gpio12.dev.parent = mst->i2c_adap->dev.parent;
463 	if (i2c_adapter_init
464 			(&mst->master_i2c_adap_gpio12, &dibx000_i2c_master_gpio12_xfer_algo,
465 			 "DiBX000 master GPIO12 I2C bus", mst) != 0)
466 		printk(KERN_ERR
467 				"DiBX000: could not initialize the master i2c_adapter\n");
468 
469 	mst->master_i2c_adap_gpio34.dev.parent = mst->i2c_adap->dev.parent;
470 	if (i2c_adapter_init
471 			(&mst->master_i2c_adap_gpio34, &dibx000_i2c_master_gpio34_xfer_algo,
472 			 "DiBX000 master GPIO34 I2C bus", mst) != 0)
473 		printk(KERN_ERR
474 				"DiBX000: could not initialize the master i2c_adapter\n");
475 
476 	mst->master_i2c_adap_gpio67.dev.parent = mst->i2c_adap->dev.parent;
477 	if (i2c_adapter_init
478 			(&mst->master_i2c_adap_gpio67, &dibx000_i2c_gated_gpio67_algo,
479 			 "DiBX000 master GPIO67 I2C bus", mst) != 0)
480 		printk(KERN_ERR
481 				"DiBX000: could not initialize the master i2c_adapter\n");
482 
483 	/* initialize the i2c-master by closing the gate */
484 	dibx000_i2c_gate_ctrl(mst, mst->i2c_write_buffer, 0, 0);
485 
486 	ret = (i2c_transfer(i2c_adap, mst->msg, 1) == 1);
487 	mutex_unlock(&mst->i2c_buffer_lock);
488 
489 	return ret;
490 }
491 
492 EXPORT_SYMBOL(dibx000_init_i2c_master);
493 
494 void dibx000_exit_i2c_master(struct dibx000_i2c_master *mst)
495 {
496 	i2c_del_adapter(&mst->gated_tuner_i2c_adap);
497 	i2c_del_adapter(&mst->master_i2c_adap_gpio12);
498 	i2c_del_adapter(&mst->master_i2c_adap_gpio34);
499 	i2c_del_adapter(&mst->master_i2c_adap_gpio67);
500 }
501 EXPORT_SYMBOL(dibx000_exit_i2c_master);
502 
503 
504 u32 systime(void)
505 {
506 	struct timespec t;
507 
508 	t = current_kernel_time();
509 	return (t.tv_sec * 10000) + (t.tv_nsec / 100000);
510 }
511 EXPORT_SYMBOL(systime);
512 
513 MODULE_AUTHOR("Patrick Boettcher <patrick.boettcher@posteo.de>");
514 MODULE_DESCRIPTION("Common function the DiBcom demodulator family");
515 MODULE_LICENSE("GPL");
516