1 // SPDX-License-Identifier: GPL-2.0-only
2 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
3
4 #include <linux/i2c.h>
5 #include <linux/mutex.h>
6 #include <linux/module.h>
7
8 #include "dibx000_common.h"
9
10 static int debug;
11 module_param(debug, int, 0644);
12 MODULE_PARM_DESC(debug, "turn on debugging (default: 0)");
13
14 #define dprintk(fmt, arg...) do { \
15 if (debug) \
16 printk(KERN_DEBUG pr_fmt("%s: " fmt), \
17 __func__, ##arg); \
18 } while (0)
19
dibx000_write_word(struct dibx000_i2c_master * mst,u16 reg,u16 val)20 static int dibx000_write_word(struct dibx000_i2c_master *mst, u16 reg, u16 val)
21 {
22 int ret;
23
24 if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
25 dprintk("could not acquire lock\n");
26 return -EINVAL;
27 }
28
29 mst->i2c_write_buffer[0] = (reg >> 8) & 0xff;
30 mst->i2c_write_buffer[1] = reg & 0xff;
31 mst->i2c_write_buffer[2] = (val >> 8) & 0xff;
32 mst->i2c_write_buffer[3] = val & 0xff;
33
34 memset(mst->msg, 0, sizeof(struct i2c_msg));
35 mst->msg[0].addr = mst->i2c_addr;
36 mst->msg[0].flags = 0;
37 mst->msg[0].buf = mst->i2c_write_buffer;
38 mst->msg[0].len = 4;
39
40 ret = i2c_transfer(mst->i2c_adap, mst->msg, 1) != 1 ? -EREMOTEIO : 0;
41 mutex_unlock(&mst->i2c_buffer_lock);
42
43 return ret;
44 }
45
dibx000_read_word(struct dibx000_i2c_master * mst,u16 reg)46 static u16 dibx000_read_word(struct dibx000_i2c_master *mst, u16 reg)
47 {
48 u16 ret;
49
50 if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
51 dprintk("could not acquire lock\n");
52 return 0;
53 }
54
55 mst->i2c_write_buffer[0] = reg >> 8;
56 mst->i2c_write_buffer[1] = reg & 0xff;
57
58 memset(mst->msg, 0, 2 * sizeof(struct i2c_msg));
59 mst->msg[0].addr = mst->i2c_addr;
60 mst->msg[0].flags = 0;
61 mst->msg[0].buf = mst->i2c_write_buffer;
62 mst->msg[0].len = 2;
63 mst->msg[1].addr = mst->i2c_addr;
64 mst->msg[1].flags = I2C_M_RD;
65 mst->msg[1].buf = mst->i2c_read_buffer;
66 mst->msg[1].len = 2;
67
68 if (i2c_transfer(mst->i2c_adap, mst->msg, 2) != 2)
69 dprintk("i2c read error on %d\n", reg);
70
71 ret = (mst->i2c_read_buffer[0] << 8) | mst->i2c_read_buffer[1];
72 mutex_unlock(&mst->i2c_buffer_lock);
73
74 return ret;
75 }
76
dibx000_is_i2c_done(struct dibx000_i2c_master * mst)77 static int dibx000_is_i2c_done(struct dibx000_i2c_master *mst)
78 {
79 int i = 100;
80 u16 status;
81
82 while (((status = dibx000_read_word(mst, mst->base_reg + 2)) & 0x0100) == 0 && --i > 0)
83 ;
84
85 /* i2c timed out */
86 if (i == 0)
87 return -EREMOTEIO;
88
89 /* no acknowledge */
90 if ((status & 0x0080) == 0)
91 return -EREMOTEIO;
92
93 return 0;
94 }
95
dibx000_master_i2c_write(struct dibx000_i2c_master * mst,struct i2c_msg * msg,u8 stop)96 static int dibx000_master_i2c_write(struct dibx000_i2c_master *mst, struct i2c_msg *msg, u8 stop)
97 {
98 u16 data;
99 u16 da;
100 u16 i;
101 u16 txlen = msg->len, len;
102 const u8 *b = msg->buf;
103
104 while (txlen) {
105 dibx000_read_word(mst, mst->base_reg + 2);
106
107 len = txlen > 8 ? 8 : txlen;
108 for (i = 0; i < len; i += 2) {
109 data = *b++ << 8;
110 if (i+1 < len)
111 data |= *b++;
112 dibx000_write_word(mst, mst->base_reg, data);
113 }
114 da = (((u8) (msg->addr)) << 9) |
115 (1 << 8) |
116 (1 << 7) |
117 (0 << 6) |
118 (0 << 5) |
119 ((len & 0x7) << 2) |
120 (0 << 1) |
121 (0 << 0);
122
123 if (txlen == msg->len)
124 da |= 1 << 5; /* start */
125
126 if (txlen-len == 0 && stop)
127 da |= 1 << 6; /* stop */
128
129 dibx000_write_word(mst, mst->base_reg+1, da);
130
131 if (dibx000_is_i2c_done(mst) != 0)
132 return -EREMOTEIO;
133 txlen -= len;
134 }
135
136 return 0;
137 }
138
dibx000_master_i2c_read(struct dibx000_i2c_master * mst,struct i2c_msg * msg)139 static int dibx000_master_i2c_read(struct dibx000_i2c_master *mst, struct i2c_msg *msg)
140 {
141 u16 da;
142 u8 *b = msg->buf;
143 u16 rxlen = msg->len, len;
144
145 while (rxlen) {
146 len = rxlen > 8 ? 8 : rxlen;
147 da = (((u8) (msg->addr)) << 9) |
148 (1 << 8) |
149 (1 << 7) |
150 (0 << 6) |
151 (0 << 5) |
152 ((len & 0x7) << 2) |
153 (1 << 1) |
154 (0 << 0);
155
156 if (rxlen == msg->len)
157 da |= 1 << 5; /* start */
158
159 if (rxlen-len == 0)
160 da |= 1 << 6; /* stop */
161 dibx000_write_word(mst, mst->base_reg+1, da);
162
163 if (dibx000_is_i2c_done(mst) != 0)
164 return -EREMOTEIO;
165
166 rxlen -= len;
167
168 while (len) {
169 da = dibx000_read_word(mst, mst->base_reg);
170 *b++ = (da >> 8) & 0xff;
171 len--;
172 if (len >= 1) {
173 *b++ = da & 0xff;
174 len--;
175 }
176 }
177 }
178
179 return 0;
180 }
181
dibx000_i2c_set_speed(struct i2c_adapter * i2c_adap,u16 speed)182 int dibx000_i2c_set_speed(struct i2c_adapter *i2c_adap, u16 speed)
183 {
184 struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
185
186 if (mst->device_rev < DIB7000MC && speed < 235)
187 speed = 235;
188 return dibx000_write_word(mst, mst->base_reg + 3, (u16)(60000 / speed));
189
190 }
191 EXPORT_SYMBOL(dibx000_i2c_set_speed);
192
dibx000_i2c_func(struct i2c_adapter * adapter)193 static u32 dibx000_i2c_func(struct i2c_adapter *adapter)
194 {
195 return I2C_FUNC_I2C;
196 }
197
dibx000_i2c_select_interface(struct dibx000_i2c_master * mst,enum dibx000_i2c_interface intf)198 static int dibx000_i2c_select_interface(struct dibx000_i2c_master *mst,
199 enum dibx000_i2c_interface intf)
200 {
201 if (mst->device_rev > DIB3000MC && mst->selected_interface != intf) {
202 dprintk("selecting interface: %d\n", intf);
203 mst->selected_interface = intf;
204 return dibx000_write_word(mst, mst->base_reg + 4, intf);
205 }
206 return 0;
207 }
208
dibx000_i2c_master_xfer_gpio12(struct i2c_adapter * i2c_adap,struct i2c_msg msg[],int num)209 static int dibx000_i2c_master_xfer_gpio12(struct i2c_adapter *i2c_adap, struct i2c_msg msg[], int num)
210 {
211 struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
212 int msg_index;
213 int ret = 0;
214
215 dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_1_2);
216 for (msg_index = 0; msg_index < num; msg_index++) {
217 if (msg[msg_index].flags & I2C_M_RD) {
218 ret = dibx000_master_i2c_read(mst, &msg[msg_index]);
219 if (ret != 0)
220 return 0;
221 } else {
222 ret = dibx000_master_i2c_write(mst, &msg[msg_index], 1);
223 if (ret != 0)
224 return 0;
225 }
226 }
227
228 return num;
229 }
230
dibx000_i2c_master_xfer_gpio34(struct i2c_adapter * i2c_adap,struct i2c_msg msg[],int num)231 static int dibx000_i2c_master_xfer_gpio34(struct i2c_adapter *i2c_adap, struct i2c_msg msg[], int num)
232 {
233 struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
234 int msg_index;
235 int ret = 0;
236
237 dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_3_4);
238 for (msg_index = 0; msg_index < num; msg_index++) {
239 if (msg[msg_index].flags & I2C_M_RD) {
240 ret = dibx000_master_i2c_read(mst, &msg[msg_index]);
241 if (ret != 0)
242 return 0;
243 } else {
244 ret = dibx000_master_i2c_write(mst, &msg[msg_index], 1);
245 if (ret != 0)
246 return 0;
247 }
248 }
249
250 return num;
251 }
252
253 static struct i2c_algorithm dibx000_i2c_master_gpio12_xfer_algo = {
254 .master_xfer = dibx000_i2c_master_xfer_gpio12,
255 .functionality = dibx000_i2c_func,
256 };
257
258 static struct i2c_algorithm dibx000_i2c_master_gpio34_xfer_algo = {
259 .master_xfer = dibx000_i2c_master_xfer_gpio34,
260 .functionality = dibx000_i2c_func,
261 };
262
dibx000_i2c_gate_ctrl(struct dibx000_i2c_master * mst,u8 tx[4],u8 addr,int onoff)263 static int dibx000_i2c_gate_ctrl(struct dibx000_i2c_master *mst, u8 tx[4],
264 u8 addr, int onoff)
265 {
266 u16 val;
267
268
269 if (onoff)
270 val = addr << 8; // bit 7 = use master or not, if 0, the gate is open
271 else
272 val = 1 << 7;
273
274 if (mst->device_rev > DIB7000)
275 val <<= 1;
276
277 tx[0] = (((mst->base_reg + 1) >> 8) & 0xff);
278 tx[1] = ((mst->base_reg + 1) & 0xff);
279 tx[2] = val >> 8;
280 tx[3] = val & 0xff;
281
282 return 0;
283 }
284
dibx000_i2c_gated_gpio67_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg msg[],int num)285 static int dibx000_i2c_gated_gpio67_xfer(struct i2c_adapter *i2c_adap,
286 struct i2c_msg msg[], int num)
287 {
288 struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
289 int ret;
290
291 if (num > 32) {
292 dprintk("%s: too much I2C message to be transmitted (%i). Maximum is 32",
293 __func__, num);
294 return -ENOMEM;
295 }
296
297 dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_6_7);
298
299 if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
300 dprintk("could not acquire lock\n");
301 return -EINVAL;
302 }
303
304 memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));
305
306 /* open the gate */
307 dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
308 mst->msg[0].addr = mst->i2c_addr;
309 mst->msg[0].buf = &mst->i2c_write_buffer[0];
310 mst->msg[0].len = 4;
311
312 memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);
313
314 /* close the gate */
315 dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
316 mst->msg[num + 1].addr = mst->i2c_addr;
317 mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
318 mst->msg[num + 1].len = 4;
319
320 ret = (i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ?
321 num : -EIO);
322
323 mutex_unlock(&mst->i2c_buffer_lock);
324 return ret;
325 }
326
327 static struct i2c_algorithm dibx000_i2c_gated_gpio67_algo = {
328 .master_xfer = dibx000_i2c_gated_gpio67_xfer,
329 .functionality = dibx000_i2c_func,
330 };
331
dibx000_i2c_gated_tuner_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg msg[],int num)332 static int dibx000_i2c_gated_tuner_xfer(struct i2c_adapter *i2c_adap,
333 struct i2c_msg msg[], int num)
334 {
335 struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
336 int ret;
337
338 if (num > 32) {
339 dprintk("%s: too much I2C message to be transmitted (%i). Maximum is 32",
340 __func__, num);
341 return -ENOMEM;
342 }
343
344 dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);
345
346 if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
347 dprintk("could not acquire lock\n");
348 return -EINVAL;
349 }
350 memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));
351
352 /* open the gate */
353 dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
354 mst->msg[0].addr = mst->i2c_addr;
355 mst->msg[0].buf = &mst->i2c_write_buffer[0];
356 mst->msg[0].len = 4;
357
358 memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);
359
360 /* close the gate */
361 dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
362 mst->msg[num + 1].addr = mst->i2c_addr;
363 mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
364 mst->msg[num + 1].len = 4;
365
366 ret = (i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ?
367 num : -EIO);
368 mutex_unlock(&mst->i2c_buffer_lock);
369 return ret;
370 }
371
372 static struct i2c_algorithm dibx000_i2c_gated_tuner_algo = {
373 .master_xfer = dibx000_i2c_gated_tuner_xfer,
374 .functionality = dibx000_i2c_func,
375 };
376
dibx000_get_i2c_adapter(struct dibx000_i2c_master * mst,enum dibx000_i2c_interface intf,int gating)377 struct i2c_adapter *dibx000_get_i2c_adapter(struct dibx000_i2c_master *mst,
378 enum dibx000_i2c_interface intf,
379 int gating)
380 {
381 struct i2c_adapter *i2c = NULL;
382
383 switch (intf) {
384 case DIBX000_I2C_INTERFACE_TUNER:
385 if (gating)
386 i2c = &mst->gated_tuner_i2c_adap;
387 break;
388 case DIBX000_I2C_INTERFACE_GPIO_1_2:
389 if (!gating)
390 i2c = &mst->master_i2c_adap_gpio12;
391 break;
392 case DIBX000_I2C_INTERFACE_GPIO_3_4:
393 if (!gating)
394 i2c = &mst->master_i2c_adap_gpio34;
395 break;
396 case DIBX000_I2C_INTERFACE_GPIO_6_7:
397 if (gating)
398 i2c = &mst->master_i2c_adap_gpio67;
399 break;
400 default:
401 pr_err("incorrect I2C interface selected\n");
402 break;
403 }
404
405 return i2c;
406 }
407
408 EXPORT_SYMBOL(dibx000_get_i2c_adapter);
409
dibx000_reset_i2c_master(struct dibx000_i2c_master * mst)410 void dibx000_reset_i2c_master(struct dibx000_i2c_master *mst)
411 {
412 /* initialize the i2c-master by closing the gate */
413 u8 tx[4];
414 struct i2c_msg m = {.addr = mst->i2c_addr,.buf = tx,.len = 4 };
415
416 dibx000_i2c_gate_ctrl(mst, tx, 0, 0);
417 i2c_transfer(mst->i2c_adap, &m, 1);
418 mst->selected_interface = 0xff; // the first time force a select of the I2C
419 dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);
420 }
421
422 EXPORT_SYMBOL(dibx000_reset_i2c_master);
423
i2c_adapter_init(struct i2c_adapter * i2c_adap,struct i2c_algorithm * algo,const char * name,struct dibx000_i2c_master * mst)424 static int i2c_adapter_init(struct i2c_adapter *i2c_adap,
425 struct i2c_algorithm *algo, const char *name,
426 struct dibx000_i2c_master *mst)
427 {
428 strscpy(i2c_adap->name, name, sizeof(i2c_adap->name));
429 i2c_adap->algo = algo;
430 i2c_adap->algo_data = NULL;
431 i2c_set_adapdata(i2c_adap, mst);
432 if (i2c_add_adapter(i2c_adap) < 0)
433 return -ENODEV;
434 return 0;
435 }
436
dibx000_init_i2c_master(struct dibx000_i2c_master * mst,u16 device_rev,struct i2c_adapter * i2c_adap,u8 i2c_addr)437 int dibx000_init_i2c_master(struct dibx000_i2c_master *mst, u16 device_rev,
438 struct i2c_adapter *i2c_adap, u8 i2c_addr)
439 {
440 int ret;
441
442 mutex_init(&mst->i2c_buffer_lock);
443 if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
444 dprintk("could not acquire lock\n");
445 return -EINVAL;
446 }
447 memset(mst->msg, 0, sizeof(struct i2c_msg));
448 mst->msg[0].addr = i2c_addr >> 1;
449 mst->msg[0].flags = 0;
450 mst->msg[0].buf = mst->i2c_write_buffer;
451 mst->msg[0].len = 4;
452
453 mst->device_rev = device_rev;
454 mst->i2c_adap = i2c_adap;
455 mst->i2c_addr = i2c_addr >> 1;
456
457 if (device_rev == DIB7000P || device_rev == DIB8000)
458 mst->base_reg = 1024;
459 else
460 mst->base_reg = 768;
461
462 mst->gated_tuner_i2c_adap.dev.parent = mst->i2c_adap->dev.parent;
463 if (i2c_adapter_init
464 (&mst->gated_tuner_i2c_adap, &dibx000_i2c_gated_tuner_algo,
465 "DiBX000 tuner I2C bus", mst) != 0)
466 pr_err("could not initialize the tuner i2c_adapter\n");
467
468 mst->master_i2c_adap_gpio12.dev.parent = mst->i2c_adap->dev.parent;
469 if (i2c_adapter_init
470 (&mst->master_i2c_adap_gpio12, &dibx000_i2c_master_gpio12_xfer_algo,
471 "DiBX000 master GPIO12 I2C bus", mst) != 0)
472 pr_err("could not initialize the master i2c_adapter\n");
473
474 mst->master_i2c_adap_gpio34.dev.parent = mst->i2c_adap->dev.parent;
475 if (i2c_adapter_init
476 (&mst->master_i2c_adap_gpio34, &dibx000_i2c_master_gpio34_xfer_algo,
477 "DiBX000 master GPIO34 I2C bus", mst) != 0)
478 pr_err("could not initialize the master i2c_adapter\n");
479
480 mst->master_i2c_adap_gpio67.dev.parent = mst->i2c_adap->dev.parent;
481 if (i2c_adapter_init
482 (&mst->master_i2c_adap_gpio67, &dibx000_i2c_gated_gpio67_algo,
483 "DiBX000 master GPIO67 I2C bus", mst) != 0)
484 pr_err("could not initialize the master i2c_adapter\n");
485
486 /* initialize the i2c-master by closing the gate */
487 dibx000_i2c_gate_ctrl(mst, mst->i2c_write_buffer, 0, 0);
488
489 ret = (i2c_transfer(i2c_adap, mst->msg, 1) == 1);
490 mutex_unlock(&mst->i2c_buffer_lock);
491
492 return ret;
493 }
494
495 EXPORT_SYMBOL(dibx000_init_i2c_master);
496
dibx000_exit_i2c_master(struct dibx000_i2c_master * mst)497 void dibx000_exit_i2c_master(struct dibx000_i2c_master *mst)
498 {
499 i2c_del_adapter(&mst->gated_tuner_i2c_adap);
500 i2c_del_adapter(&mst->master_i2c_adap_gpio12);
501 i2c_del_adapter(&mst->master_i2c_adap_gpio34);
502 i2c_del_adapter(&mst->master_i2c_adap_gpio67);
503 }
504 EXPORT_SYMBOL(dibx000_exit_i2c_master);
505
506 MODULE_AUTHOR("Patrick Boettcher <patrick.boettcher@posteo.de>");
507 MODULE_DESCRIPTION("Common function the DiBcom demodulator family");
508 MODULE_LICENSE("GPL");
509