15eea2b2c90fecdb4bd6125e5afa4c18df9ef006
[sfrench/cifs-2.6.git] / drivers / media / radio / si470x / radio-si470x-i2c.c
1 /*
2  * drivers/media/radio/si470x/radio-si470x-i2c.c
3  *
4  * I2C driver for radios with Silicon Labs Si470x FM Radio Receivers
5  *
6  * Copyright (c) 2009 Samsung Electronics Co.Ltd
7  * Author: Joonyoung Shim <jy0922.shim@samsung.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  */
19
20
21 /* driver definitions */
22 #define DRIVER_AUTHOR "Joonyoung Shim <jy0922.shim@samsung.com>";
23 #define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver"
24 #define DRIVER_DESC "I2C radio driver for Si470x FM Radio Receivers"
25 #define DRIVER_VERSION "1.0.2"
26
27 /* kernel includes */
28 #include <linux/i2c.h>
29 #include <linux/slab.h>
30 #include <linux/delay.h>
31 #include <linux/gpio/consumer.h>
32 #include <linux/interrupt.h>
33
34 #include "radio-si470x.h"
35
36
37 /* I2C Device ID List */
38 static const struct i2c_device_id si470x_i2c_id[] = {
39         /* Generic Entry */
40         { "si470x", 0 },
41         /* Terminating entry */
42         { }
43 };
44 MODULE_DEVICE_TABLE(i2c, si470x_i2c_id);
45
46
47 /**************************************************************************
48  * Module Parameters
49  **************************************************************************/
50
51 /* Radio Nr */
52 static int radio_nr = -1;
53 module_param(radio_nr, int, 0444);
54 MODULE_PARM_DESC(radio_nr, "Radio Nr");
55
56 /* RDS buffer blocks */
57 static unsigned int rds_buf = 100;
58 module_param(rds_buf, uint, 0444);
59 MODULE_PARM_DESC(rds_buf, "RDS buffer entries: *100*");
60
61 /* RDS maximum block errors */
62 static unsigned short max_rds_errors = 1;
63 /* 0 means   0  errors requiring correction */
64 /* 1 means 1-2  errors requiring correction (used by original USBRadio.exe) */
65 /* 2 means 3-5  errors requiring correction */
66 /* 3 means   6+ errors or errors in checkword, correction not possible */
67 module_param(max_rds_errors, ushort, 0644);
68 MODULE_PARM_DESC(max_rds_errors, "RDS maximum block errors: *1*");
69
70
71
72 /**************************************************************************
73  * I2C Definitions
74  **************************************************************************/
75
76 /* Write starts with the upper byte of register 0x02 */
77 #define WRITE_REG_NUM           8
78 #define WRITE_INDEX(i)          (i + 0x02)
79
80 /* Read starts with the upper byte of register 0x0a */
81 #define READ_REG_NUM            RADIO_REGISTER_NUM
82 #define READ_INDEX(i)           ((i + RADIO_REGISTER_NUM - 0x0a) % READ_REG_NUM)
83
84
85
86 /**************************************************************************
87  * General Driver Functions - REGISTERs
88  **************************************************************************/
89
90 /*
91  * si470x_get_register - read register
92  */
93 static int si470x_get_register(struct si470x_device *radio, int regnr)
94 {
95         __be16 buf[READ_REG_NUM];
96         struct i2c_msg msgs[1] = {
97                 {
98                         .addr = radio->client->addr,
99                         .flags = I2C_M_RD,
100                         .len = sizeof(u16) * READ_REG_NUM,
101                         .buf = (void *)buf
102                 },
103         };
104
105         if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
106                 return -EIO;
107
108         radio->registers[regnr] = __be16_to_cpu(buf[READ_INDEX(regnr)]);
109
110         return 0;
111 }
112
113
114 /*
115  * si470x_set_register - write register
116  */
117 static int si470x_set_register(struct si470x_device *radio, int regnr)
118 {
119         int i;
120         __be16 buf[WRITE_REG_NUM];
121         struct i2c_msg msgs[1] = {
122                 {
123                         .addr = radio->client->addr,
124                         .len = sizeof(u16) * WRITE_REG_NUM,
125                         .buf = (void *)buf
126                 },
127         };
128
129         for (i = 0; i < WRITE_REG_NUM; i++)
130                 buf[i] = __cpu_to_be16(radio->registers[WRITE_INDEX(i)]);
131
132         if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
133                 return -EIO;
134
135         return 0;
136 }
137
138
139
140 /**************************************************************************
141  * General Driver Functions - ENTIRE REGISTERS
142  **************************************************************************/
143
144 /*
145  * si470x_get_all_registers - read entire registers
146  */
147 static int si470x_get_all_registers(struct si470x_device *radio)
148 {
149         int i;
150         __be16 buf[READ_REG_NUM];
151         struct i2c_msg msgs[1] = {
152                 {
153                         .addr = radio->client->addr,
154                         .flags = I2C_M_RD,
155                         .len = sizeof(u16) * READ_REG_NUM,
156                         .buf = (void *)buf
157                 },
158         };
159
160         if (i2c_transfer(radio->client->adapter, msgs, 1) != 1)
161                 return -EIO;
162
163         for (i = 0; i < READ_REG_NUM; i++)
164                 radio->registers[i] = __be16_to_cpu(buf[READ_INDEX(i)]);
165
166         return 0;
167 }
168
169
170
171 /**************************************************************************
172  * File Operations Interface
173  **************************************************************************/
174
175 /*
176  * si470x_fops_open - file open
177  */
178 static int si470x_fops_open(struct file *file)
179 {
180         struct si470x_device *radio = video_drvdata(file);
181         int retval = v4l2_fh_open(file);
182
183         if (retval)
184                 return retval;
185
186         if (v4l2_fh_is_singular_file(file)) {
187                 /* start radio */
188                 retval = si470x_start(radio);
189                 if (retval < 0)
190                         goto done;
191
192                 /* enable RDS / STC interrupt */
193                 radio->registers[SYSCONFIG1] |= SYSCONFIG1_RDSIEN;
194                 radio->registers[SYSCONFIG1] |= SYSCONFIG1_STCIEN;
195                 radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_GPIO2;
196                 radio->registers[SYSCONFIG1] |= 0x1 << 2;
197                 retval = si470x_set_register(radio, SYSCONFIG1);
198         }
199
200 done:
201         if (retval)
202                 v4l2_fh_release(file);
203         return retval;
204 }
205
206
207 /*
208  * si470x_fops_release - file release
209  */
210 static int si470x_fops_release(struct file *file)
211 {
212         struct si470x_device *radio = video_drvdata(file);
213
214         if (v4l2_fh_is_singular_file(file))
215                 /* stop radio */
216                 si470x_stop(radio);
217
218         return v4l2_fh_release(file);
219 }
220
221
222
223 /**************************************************************************
224  * Video4Linux Interface
225  **************************************************************************/
226
227 /*
228  * si470x_vidioc_querycap - query device capabilities
229  */
230 static int si470x_vidioc_querycap(struct file *file, void *priv,
231                                   struct v4l2_capability *capability)
232 {
233         strscpy(capability->driver, DRIVER_NAME, sizeof(capability->driver));
234         strscpy(capability->card, DRIVER_CARD, sizeof(capability->card));
235         capability->device_caps = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_READWRITE |
236                 V4L2_CAP_TUNER | V4L2_CAP_RADIO | V4L2_CAP_RDS_CAPTURE;
237         capability->capabilities = capability->device_caps | V4L2_CAP_DEVICE_CAPS;
238
239         return 0;
240 }
241
242
243
244 /**************************************************************************
245  * I2C Interface
246  **************************************************************************/
247
248 /*
249  * si470x_i2c_interrupt - interrupt handler
250  */
251 static irqreturn_t si470x_i2c_interrupt(int irq, void *dev_id)
252 {
253         struct si470x_device *radio = dev_id;
254         unsigned char regnr;
255         unsigned char blocknum;
256         unsigned short bler; /* rds block errors */
257         unsigned short rds;
258         unsigned char tmpbuf[3];
259         int retval = 0;
260
261         /* check Seek/Tune Complete */
262         retval = si470x_get_register(radio, STATUSRSSI);
263         if (retval < 0)
264                 goto end;
265
266         if (radio->registers[STATUSRSSI] & STATUSRSSI_STC)
267                 complete(&radio->completion);
268
269         /* safety checks */
270         if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
271                 goto end;
272
273         /* Update RDS registers */
274         for (regnr = 1; regnr < RDS_REGISTER_NUM; regnr++) {
275                 retval = si470x_get_register(radio, STATUSRSSI + regnr);
276                 if (retval < 0)
277                         goto end;
278         }
279
280         /* get rds blocks */
281         if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSR) == 0)
282                 /* No RDS group ready, better luck next time */
283                 goto end;
284
285         for (blocknum = 0; blocknum < 4; blocknum++) {
286                 switch (blocknum) {
287                 default:
288                         bler = (radio->registers[STATUSRSSI] &
289                                         STATUSRSSI_BLERA) >> 9;
290                         rds = radio->registers[RDSA];
291                         break;
292                 case 1:
293                         bler = (radio->registers[READCHAN] &
294                                         READCHAN_BLERB) >> 14;
295                         rds = radio->registers[RDSB];
296                         break;
297                 case 2:
298                         bler = (radio->registers[READCHAN] &
299                                         READCHAN_BLERC) >> 12;
300                         rds = radio->registers[RDSC];
301                         break;
302                 case 3:
303                         bler = (radio->registers[READCHAN] &
304                                         READCHAN_BLERD) >> 10;
305                         rds = radio->registers[RDSD];
306                         break;
307                 }
308
309                 /* Fill the V4L2 RDS buffer */
310                 put_unaligned_le16(rds, &tmpbuf);
311                 tmpbuf[2] = blocknum;           /* offset name */
312                 tmpbuf[2] |= blocknum << 3;     /* received offset */
313                 if (bler > max_rds_errors)
314                         tmpbuf[2] |= 0x80;      /* uncorrectable errors */
315                 else if (bler > 0)
316                         tmpbuf[2] |= 0x40;      /* corrected error(s) */
317
318                 /* copy RDS block to internal buffer */
319                 memcpy(&radio->buffer[radio->wr_index], &tmpbuf, 3);
320                 radio->wr_index += 3;
321
322                 /* wrap write pointer */
323                 if (radio->wr_index >= radio->buf_size)
324                         radio->wr_index = 0;
325
326                 /* check for overflow */
327                 if (radio->wr_index == radio->rd_index) {
328                         /* increment and wrap read pointer */
329                         radio->rd_index += 3;
330                         if (radio->rd_index >= radio->buf_size)
331                                 radio->rd_index = 0;
332                 }
333         }
334
335         if (radio->wr_index != radio->rd_index)
336                 wake_up_interruptible(&radio->read_queue);
337
338 end:
339         return IRQ_HANDLED;
340 }
341
342
343 /*
344  * si470x_i2c_probe - probe for the device
345  */
346 static int si470x_i2c_probe(struct i2c_client *client,
347                             const struct i2c_device_id *id)
348 {
349         struct si470x_device *radio;
350         int retval = 0;
351         unsigned char version_warning = 0;
352
353         /* private data allocation and initialization */
354         radio = devm_kzalloc(&client->dev, sizeof(*radio), GFP_KERNEL);
355         if (!radio) {
356                 retval = -ENOMEM;
357                 goto err_initial;
358         }
359
360         radio->client = client;
361         radio->band = 1; /* Default to 76 - 108 MHz */
362         mutex_init(&radio->lock);
363         init_completion(&radio->completion);
364
365         radio->get_register = si470x_get_register;
366         radio->set_register = si470x_set_register;
367         radio->fops_open = si470x_fops_open;
368         radio->fops_release = si470x_fops_release;
369         radio->vidioc_querycap = si470x_vidioc_querycap;
370
371         retval = v4l2_device_register(&client->dev, &radio->v4l2_dev);
372         if (retval < 0) {
373                 dev_err(&client->dev, "couldn't register v4l2_device\n");
374                 goto err_initial;
375         }
376
377         v4l2_ctrl_handler_init(&radio->hdl, 2);
378         v4l2_ctrl_new_std(&radio->hdl, &si470x_ctrl_ops,
379                         V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
380         v4l2_ctrl_new_std(&radio->hdl, &si470x_ctrl_ops,
381                         V4L2_CID_AUDIO_VOLUME, 0, 15, 1, 15);
382         if (radio->hdl.error) {
383                 retval = radio->hdl.error;
384                 dev_err(&client->dev, "couldn't register control\n");
385                 goto err_dev;
386         }
387
388         /* video device initialization */
389         radio->videodev = si470x_viddev_template;
390         radio->videodev.ctrl_handler = &radio->hdl;
391         radio->videodev.lock = &radio->lock;
392         radio->videodev.v4l2_dev = &radio->v4l2_dev;
393         radio->videodev.release = video_device_release_empty;
394         video_set_drvdata(&radio->videodev, radio);
395
396         radio->gpio_reset = devm_gpiod_get_optional(&client->dev, "reset",
397                                                     GPIOD_OUT_LOW);
398         if (IS_ERR(radio->gpio_reset)) {
399                 retval = PTR_ERR(radio->gpio_reset);
400                 dev_err(&client->dev, "Failed to request gpio: %d\n", retval);
401                 goto err_all;
402         }
403
404         if (radio->gpio_reset)
405                 gpiod_set_value(radio->gpio_reset, 1);
406
407         /* power up : need 110ms */
408         radio->registers[POWERCFG] = POWERCFG_ENABLE;
409         if (si470x_set_register(radio, POWERCFG) < 0) {
410                 retval = -EIO;
411                 goto err_all;
412         }
413         msleep(110);
414
415         /* get device and chip versions */
416         if (si470x_get_all_registers(radio) < 0) {
417                 retval = -EIO;
418                 goto err_all;
419         }
420         dev_info(&client->dev, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
421                         radio->registers[DEVICEID], radio->registers[SI_CHIPID]);
422         if ((radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE) < RADIO_FW_VERSION) {
423                 dev_warn(&client->dev,
424                         "This driver is known to work with firmware version %hu,\n",
425                         RADIO_FW_VERSION);
426                 dev_warn(&client->dev,
427                         "but the device has firmware version %hu.\n",
428                         radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE);
429                 version_warning = 1;
430         }
431
432         /* give out version warning */
433         if (version_warning == 1) {
434                 dev_warn(&client->dev,
435                         "If you have some trouble using this driver,\n");
436                 dev_warn(&client->dev,
437                         "please report to V4L ML at linux-media@vger.kernel.org\n");
438         }
439
440         /* set initial frequency */
441         si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */
442
443         /* rds buffer allocation */
444         radio->buf_size = rds_buf * 3;
445         radio->buffer = devm_kmalloc(&client->dev, radio->buf_size, GFP_KERNEL);
446         if (!radio->buffer) {
447                 retval = -EIO;
448                 goto err_all;
449         }
450
451         /* rds buffer configuration */
452         radio->wr_index = 0;
453         radio->rd_index = 0;
454         init_waitqueue_head(&radio->read_queue);
455
456         retval = devm_request_threaded_irq(&client->dev, client->irq, NULL,
457                                            si470x_i2c_interrupt,
458                                            IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
459                                            DRIVER_NAME, radio);
460         if (retval) {
461                 dev_err(&client->dev, "Failed to register interrupt\n");
462                 goto err_all;
463         }
464
465         /* register video device */
466         retval = video_register_device(&radio->videodev, VFL_TYPE_RADIO,
467                         radio_nr);
468         if (retval) {
469                 dev_warn(&client->dev, "Could not register video device\n");
470                 goto err_all;
471         }
472         i2c_set_clientdata(client, radio);
473
474         return 0;
475 err_all:
476         v4l2_ctrl_handler_free(&radio->hdl);
477 err_dev:
478         v4l2_device_unregister(&radio->v4l2_dev);
479 err_initial:
480         return retval;
481 }
482
483
484 /*
485  * si470x_i2c_remove - remove the device
486  */
487 static int si470x_i2c_remove(struct i2c_client *client)
488 {
489         struct si470x_device *radio = i2c_get_clientdata(client);
490
491         video_unregister_device(&radio->videodev);
492
493         if (radio->gpio_reset)
494                 gpiod_set_value(radio->gpio_reset, 0);
495
496         return 0;
497 }
498
499
500 #ifdef CONFIG_PM_SLEEP
501 /*
502  * si470x_i2c_suspend - suspend the device
503  */
504 static int si470x_i2c_suspend(struct device *dev)
505 {
506         struct i2c_client *client = to_i2c_client(dev);
507         struct si470x_device *radio = i2c_get_clientdata(client);
508
509         /* power down */
510         radio->registers[POWERCFG] |= POWERCFG_DISABLE;
511         if (si470x_set_register(radio, POWERCFG) < 0)
512                 return -EIO;
513
514         return 0;
515 }
516
517
518 /*
519  * si470x_i2c_resume - resume the device
520  */
521 static int si470x_i2c_resume(struct device *dev)
522 {
523         struct i2c_client *client = to_i2c_client(dev);
524         struct si470x_device *radio = i2c_get_clientdata(client);
525
526         /* power up : need 110ms */
527         radio->registers[POWERCFG] |= POWERCFG_ENABLE;
528         if (si470x_set_register(radio, POWERCFG) < 0)
529                 return -EIO;
530         msleep(110);
531
532         return 0;
533 }
534
535 static SIMPLE_DEV_PM_OPS(si470x_i2c_pm, si470x_i2c_suspend, si470x_i2c_resume);
536 #endif
537
538 #if IS_ENABLED(CONFIG_OF)
539 static const struct of_device_id si470x_of_match[] = {
540         { .compatible = "silabs,si470x" },
541         { },
542 };
543 MODULE_DEVICE_TABLE(of, si470x_of_match);
544 #endif
545
546 /*
547  * si470x_i2c_driver - i2c driver interface
548  */
549 static struct i2c_driver si470x_i2c_driver = {
550         .driver = {
551                 .name           = "si470x",
552                 .of_match_table = of_match_ptr(si470x_of_match),
553 #ifdef CONFIG_PM_SLEEP
554                 .pm             = &si470x_i2c_pm,
555 #endif
556         },
557         .probe                  = si470x_i2c_probe,
558         .remove                 = si470x_i2c_remove,
559         .id_table               = si470x_i2c_id,
560 };
561
562 module_i2c_driver(si470x_i2c_driver);
563
564 MODULE_LICENSE("GPL");
565 MODULE_AUTHOR(DRIVER_AUTHOR);
566 MODULE_DESCRIPTION(DRIVER_DESC);
567 MODULE_VERSION(DRIVER_VERSION);