1 /*
2  *  FM Driver for Connectivity chip of Texas Instruments.
3  *  This file provides interfaces to V4L2 subsystem.
4  *
5  *  This module registers with V4L2 subsystem as Radio
6  *  data system interface (/dev/radio). During the registration,
7  *  it will expose two set of function pointers.
8  *
9  *    1) File operation related API (open, close, read, write, poll...etc).
10  *    2) Set of V4L2 IOCTL complaint API.
11  *
12  *  Copyright (C) 2011 Texas Instruments
13  *  Author: Raja Mani <raja_mani@ti.com>
14  *  Author: Manjunatha Halli <manjunatha_halli@ti.com>
15  *
16  *  This program is free software; you can redistribute it and/or modify
17  *  it under the terms of the GNU General Public License version 2 as
18  *  published by the Free Software Foundation.
19  *
20  *  This program is distributed in the hope that it will be useful,
21  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
22  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
23  *  GNU General Public License for more details.
24  *
25  */
26 
27 #include <linux/export.h>
28 
29 #include "fmdrv.h"
30 #include "fmdrv_v4l2.h"
31 #include "fmdrv_common.h"
32 #include "fmdrv_rx.h"
33 #include "fmdrv_tx.h"
34 
35 static struct video_device gradio_dev;
36 static u8 radio_disconnected;
37 
38 /* -- V4L2 RADIO (/dev/radioX) device file operation interfaces --- */
39 
40 /* Read RX RDS data */
41 static ssize_t fm_v4l2_fops_read(struct file *file, char __user * buf,
42 					size_t count, loff_t *ppos)
43 {
44 	u8 rds_mode;
45 	int ret;
46 	struct fmdev *fmdev;
47 
48 	fmdev = video_drvdata(file);
49 
50 	if (!radio_disconnected) {
51 		fmerr("FM device is already disconnected\n");
52 		return -EIO;
53 	}
54 
55 	if (mutex_lock_interruptible(&fmdev->mutex))
56 		return -ERESTARTSYS;
57 
58 	/* Turn on RDS mode if it is disabled */
59 	ret = fm_rx_get_rds_mode(fmdev, &rds_mode);
60 	if (ret < 0) {
61 		fmerr("Unable to read current rds mode\n");
62 		goto read_unlock;
63 	}
64 
65 	if (rds_mode == FM_RDS_DISABLE) {
66 		ret = fmc_set_rds_mode(fmdev, FM_RDS_ENABLE);
67 		if (ret < 0) {
68 			fmerr("Failed to enable rds mode\n");
69 			goto read_unlock;
70 		}
71 	}
72 
73 	/* Copy RDS data from internal buffer to user buffer */
74 	ret = fmc_transfer_rds_from_internal_buff(fmdev, file, buf, count);
75 read_unlock:
76 	mutex_unlock(&fmdev->mutex);
77 	return ret;
78 }
79 
80 /* Write TX RDS data */
81 static ssize_t fm_v4l2_fops_write(struct file *file, const char __user * buf,
82 		size_t count, loff_t *ppos)
83 {
84 	struct tx_rds rds;
85 	int ret;
86 	struct fmdev *fmdev;
87 
88 	ret = copy_from_user(&rds, buf, sizeof(rds));
89 	rds.text[sizeof(rds.text) - 1] = '\0';
90 	fmdbg("(%d)type: %d, text %s, af %d\n",
91 		   ret, rds.text_type, rds.text, rds.af_freq);
92 	if (ret)
93 		return -EFAULT;
94 
95 	fmdev = video_drvdata(file);
96 	if (mutex_lock_interruptible(&fmdev->mutex))
97 		return -ERESTARTSYS;
98 	fm_tx_set_radio_text(fmdev, rds.text, rds.text_type);
99 	fm_tx_set_af(fmdev, rds.af_freq);
100 	mutex_unlock(&fmdev->mutex);
101 
102 	return sizeof(rds);
103 }
104 
105 static __poll_t fm_v4l2_fops_poll(struct file *file, struct poll_table_struct *pts)
106 {
107 	int ret;
108 	struct fmdev *fmdev;
109 
110 	fmdev = video_drvdata(file);
111 	mutex_lock(&fmdev->mutex);
112 	ret = fmc_is_rds_data_available(fmdev, file, pts);
113 	mutex_unlock(&fmdev->mutex);
114 	if (ret < 0)
115 		return EPOLLIN | EPOLLRDNORM;
116 
117 	return 0;
118 }
119 
120 /*
121  * Handle open request for "/dev/radioX" device.
122  * Start with FM RX mode as default.
123  */
124 static int fm_v4l2_fops_open(struct file *file)
125 {
126 	int ret;
127 	struct fmdev *fmdev = NULL;
128 
129 	/* Don't allow multiple open */
130 	if (radio_disconnected) {
131 		fmerr("FM device is already opened\n");
132 		return -EBUSY;
133 	}
134 
135 	fmdev = video_drvdata(file);
136 
137 	if (mutex_lock_interruptible(&fmdev->mutex))
138 		return -ERESTARTSYS;
139 	ret = fmc_prepare(fmdev);
140 	if (ret < 0) {
141 		fmerr("Unable to prepare FM CORE\n");
142 		goto open_unlock;
143 	}
144 
145 	fmdbg("Load FM RX firmware..\n");
146 
147 	ret = fmc_set_mode(fmdev, FM_MODE_RX);
148 	if (ret < 0) {
149 		fmerr("Unable to load FM RX firmware\n");
150 		goto open_unlock;
151 	}
152 	radio_disconnected = 1;
153 
154 open_unlock:
155 	mutex_unlock(&fmdev->mutex);
156 	return ret;
157 }
158 
159 static int fm_v4l2_fops_release(struct file *file)
160 {
161 	int ret;
162 	struct fmdev *fmdev;
163 
164 	fmdev = video_drvdata(file);
165 	if (!radio_disconnected) {
166 		fmdbg("FM device is already closed\n");
167 		return 0;
168 	}
169 
170 	mutex_lock(&fmdev->mutex);
171 	ret = fmc_set_mode(fmdev, FM_MODE_OFF);
172 	if (ret < 0) {
173 		fmerr("Unable to turn off the chip\n");
174 		goto release_unlock;
175 	}
176 
177 	ret = fmc_release(fmdev);
178 	if (ret < 0) {
179 		fmerr("FM CORE release failed\n");
180 		goto release_unlock;
181 	}
182 	radio_disconnected = 0;
183 
184 release_unlock:
185 	mutex_unlock(&fmdev->mutex);
186 	return ret;
187 }
188 
189 /* V4L2 RADIO (/dev/radioX) device IOCTL interfaces */
190 static int fm_v4l2_vidioc_querycap(struct file *file, void *priv,
191 		struct v4l2_capability *capability)
192 {
193 	strlcpy(capability->driver, FM_DRV_NAME, sizeof(capability->driver));
194 	strlcpy(capability->card, FM_DRV_CARD_SHORT_NAME,
195 			sizeof(capability->card));
196 	sprintf(capability->bus_info, "UART");
197 	capability->device_caps = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_TUNER |
198 		V4L2_CAP_RADIO | V4L2_CAP_MODULATOR |
199 		V4L2_CAP_AUDIO | V4L2_CAP_READWRITE |
200 		V4L2_CAP_RDS_CAPTURE;
201 	capability->capabilities = capability->device_caps |
202 		V4L2_CAP_DEVICE_CAPS;
203 
204 	return 0;
205 }
206 
207 static int fm_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
208 {
209 	struct fmdev *fmdev = container_of(ctrl->handler,
210 			struct fmdev, ctrl_handler);
211 
212 	switch (ctrl->id) {
213 	case  V4L2_CID_TUNE_ANTENNA_CAPACITOR:
214 		ctrl->val = fm_tx_get_tune_cap_val(fmdev);
215 		break;
216 	default:
217 		fmwarn("%s: Unknown IOCTL: %d\n", __func__, ctrl->id);
218 		break;
219 	}
220 
221 	return 0;
222 }
223 
224 static int fm_v4l2_s_ctrl(struct v4l2_ctrl *ctrl)
225 {
226 	struct fmdev *fmdev = container_of(ctrl->handler,
227 			struct fmdev, ctrl_handler);
228 
229 	switch (ctrl->id) {
230 	case V4L2_CID_AUDIO_VOLUME:	/* set volume */
231 		return fm_rx_set_volume(fmdev, (u16)ctrl->val);
232 
233 	case V4L2_CID_AUDIO_MUTE:	/* set mute */
234 		return fmc_set_mute_mode(fmdev, (u8)ctrl->val);
235 
236 	case V4L2_CID_TUNE_POWER_LEVEL:
237 		/* set TX power level - ext control */
238 		return fm_tx_set_pwr_lvl(fmdev, (u8)ctrl->val);
239 
240 	case V4L2_CID_TUNE_PREEMPHASIS:
241 		return fm_tx_set_preemph_filter(fmdev, (u8) ctrl->val);
242 
243 	default:
244 		return -EINVAL;
245 	}
246 }
247 
248 static int fm_v4l2_vidioc_g_audio(struct file *file, void *priv,
249 		struct v4l2_audio *audio)
250 {
251 	memset(audio, 0, sizeof(*audio));
252 	strcpy(audio->name, "Radio");
253 	audio->capability = V4L2_AUDCAP_STEREO;
254 
255 	return 0;
256 }
257 
258 static int fm_v4l2_vidioc_s_audio(struct file *file, void *priv,
259 		const struct v4l2_audio *audio)
260 {
261 	if (audio->index != 0)
262 		return -EINVAL;
263 
264 	return 0;
265 }
266 
267 /* Get tuner attributes. If current mode is NOT RX, return error */
268 static int fm_v4l2_vidioc_g_tuner(struct file *file, void *priv,
269 		struct v4l2_tuner *tuner)
270 {
271 	struct fmdev *fmdev = video_drvdata(file);
272 	u32 bottom_freq;
273 	u32 top_freq;
274 	u16 stereo_mono_mode;
275 	u16 rssilvl;
276 	int ret;
277 
278 	if (tuner->index != 0)
279 		return -EINVAL;
280 
281 	if (fmdev->curr_fmmode != FM_MODE_RX)
282 		return -EPERM;
283 
284 	ret = fm_rx_get_band_freq_range(fmdev, &bottom_freq, &top_freq);
285 	if (ret != 0)
286 		return ret;
287 
288 	ret = fm_rx_get_stereo_mono(fmdev, &stereo_mono_mode);
289 	if (ret != 0)
290 		return ret;
291 
292 	ret = fm_rx_get_rssi_level(fmdev, &rssilvl);
293 	if (ret != 0)
294 		return ret;
295 
296 	strcpy(tuner->name, "FM");
297 	tuner->type = V4L2_TUNER_RADIO;
298 	/* Store rangelow and rangehigh freq in unit of 62.5 Hz */
299 	tuner->rangelow = bottom_freq * 16;
300 	tuner->rangehigh = top_freq * 16;
301 	tuner->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO |
302 	((fmdev->rx.rds.flag == FM_RDS_ENABLE) ? V4L2_TUNER_SUB_RDS : 0);
303 	tuner->capability = V4L2_TUNER_CAP_STEREO | V4L2_TUNER_CAP_RDS |
304 			    V4L2_TUNER_CAP_LOW |
305 			    V4L2_TUNER_CAP_HWSEEK_BOUNDED |
306 			    V4L2_TUNER_CAP_HWSEEK_WRAP;
307 	tuner->audmode = (stereo_mono_mode ?
308 			  V4L2_TUNER_MODE_MONO : V4L2_TUNER_MODE_STEREO);
309 
310 	/*
311 	 * Actual rssi value lies in between -128 to +127.
312 	 * Convert this range from 0 to 255 by adding +128
313 	 */
314 	rssilvl += 128;
315 
316 	/*
317 	 * Return signal strength value should be within 0 to 65535.
318 	 * Find out correct signal radio by multiplying (65535/255) = 257
319 	 */
320 	tuner->signal = rssilvl * 257;
321 	tuner->afc = 0;
322 
323 	return ret;
324 }
325 
326 /*
327  * Set tuner attributes. If current mode is NOT RX, set to RX.
328  * Currently, we set only audio mode (mono/stereo) and RDS state (on/off).
329  * Should we set other tuner attributes, too?
330  */
331 static int fm_v4l2_vidioc_s_tuner(struct file *file, void *priv,
332 		const struct v4l2_tuner *tuner)
333 {
334 	struct fmdev *fmdev = video_drvdata(file);
335 	u16 aud_mode;
336 	u8 rds_mode;
337 	int ret;
338 
339 	if (tuner->index != 0)
340 		return -EINVAL;
341 
342 	aud_mode = (tuner->audmode == V4L2_TUNER_MODE_STEREO) ?
343 			FM_STEREO_MODE : FM_MONO_MODE;
344 	rds_mode = (tuner->rxsubchans & V4L2_TUNER_SUB_RDS) ?
345 			FM_RDS_ENABLE : FM_RDS_DISABLE;
346 
347 	if (fmdev->curr_fmmode != FM_MODE_RX) {
348 		ret = fmc_set_mode(fmdev, FM_MODE_RX);
349 		if (ret < 0) {
350 			fmerr("Failed to set RX mode\n");
351 			return ret;
352 		}
353 	}
354 
355 	ret = fmc_set_stereo_mono(fmdev, aud_mode);
356 	if (ret < 0) {
357 		fmerr("Failed to set RX stereo/mono mode\n");
358 		return ret;
359 	}
360 
361 	ret = fmc_set_rds_mode(fmdev, rds_mode);
362 	if (ret < 0)
363 		fmerr("Failed to set RX RDS mode\n");
364 
365 	return ret;
366 }
367 
368 /* Get tuner or modulator radio frequency */
369 static int fm_v4l2_vidioc_g_freq(struct file *file, void *priv,
370 		struct v4l2_frequency *freq)
371 {
372 	struct fmdev *fmdev = video_drvdata(file);
373 	int ret;
374 
375 	ret = fmc_get_freq(fmdev, &freq->frequency);
376 	if (ret < 0) {
377 		fmerr("Failed to get frequency\n");
378 		return ret;
379 	}
380 
381 	/* Frequency unit of 62.5 Hz*/
382 	freq->frequency = (u32) freq->frequency * 16;
383 
384 	return 0;
385 }
386 
387 /* Set tuner or modulator radio frequency */
388 static int fm_v4l2_vidioc_s_freq(struct file *file, void *priv,
389 		const struct v4l2_frequency *freq)
390 {
391 	struct fmdev *fmdev = video_drvdata(file);
392 
393 	/*
394 	 * As V4L2_TUNER_CAP_LOW is set 1 user sends the frequency
395 	 * in units of 62.5 Hz.
396 	 */
397 	return fmc_set_freq(fmdev, freq->frequency / 16);
398 }
399 
400 /* Set hardware frequency seek. If current mode is NOT RX, set it RX. */
401 static int fm_v4l2_vidioc_s_hw_freq_seek(struct file *file, void *priv,
402 		const struct v4l2_hw_freq_seek *seek)
403 {
404 	struct fmdev *fmdev = video_drvdata(file);
405 	int ret;
406 
407 	if (file->f_flags & O_NONBLOCK)
408 		return -EWOULDBLOCK;
409 
410 	if (fmdev->curr_fmmode != FM_MODE_RX) {
411 		ret = fmc_set_mode(fmdev, FM_MODE_RX);
412 		if (ret != 0) {
413 			fmerr("Failed to set RX mode\n");
414 			return ret;
415 		}
416 	}
417 
418 	ret = fm_rx_seek(fmdev, seek->seek_upward, seek->wrap_around,
419 			seek->spacing);
420 	if (ret < 0)
421 		fmerr("RX seek failed - %d\n", ret);
422 
423 	return ret;
424 }
425 /* Get modulator attributes. If mode is not TX, return no attributes. */
426 static int fm_v4l2_vidioc_g_modulator(struct file *file, void *priv,
427 		struct v4l2_modulator *mod)
428 {
429 	struct fmdev *fmdev = video_drvdata(file);
430 
431 	if (mod->index != 0)
432 		return -EINVAL;
433 
434 	if (fmdev->curr_fmmode != FM_MODE_TX)
435 		return -EPERM;
436 
437 	mod->txsubchans = ((fmdev->tx_data.aud_mode == FM_STEREO_MODE) ?
438 				V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO) |
439 				((fmdev->tx_data.rds.flag == FM_RDS_ENABLE) ?
440 				V4L2_TUNER_SUB_RDS : 0);
441 
442 	mod->capability = V4L2_TUNER_CAP_STEREO | V4L2_TUNER_CAP_RDS |
443 				V4L2_TUNER_CAP_LOW;
444 
445 	return 0;
446 }
447 
448 /* Set modulator attributes. If mode is not TX, set to TX. */
449 static int fm_v4l2_vidioc_s_modulator(struct file *file, void *priv,
450 		const struct v4l2_modulator *mod)
451 {
452 	struct fmdev *fmdev = video_drvdata(file);
453 	u8 rds_mode;
454 	u16 aud_mode;
455 	int ret;
456 
457 	if (mod->index != 0)
458 		return -EINVAL;
459 
460 	if (fmdev->curr_fmmode != FM_MODE_TX) {
461 		ret = fmc_set_mode(fmdev, FM_MODE_TX);
462 		if (ret != 0) {
463 			fmerr("Failed to set TX mode\n");
464 			return ret;
465 		}
466 	}
467 
468 	aud_mode = (mod->txsubchans & V4L2_TUNER_SUB_STEREO) ?
469 			FM_STEREO_MODE : FM_MONO_MODE;
470 	rds_mode = (mod->txsubchans & V4L2_TUNER_SUB_RDS) ?
471 			FM_RDS_ENABLE : FM_RDS_DISABLE;
472 	ret = fm_tx_set_stereo_mono(fmdev, aud_mode);
473 	if (ret < 0) {
474 		fmerr("Failed to set mono/stereo mode for TX\n");
475 		return ret;
476 	}
477 	ret = fm_tx_set_rds_mode(fmdev, rds_mode);
478 	if (ret < 0)
479 		fmerr("Failed to set rds mode for TX\n");
480 
481 	return ret;
482 }
483 
484 static const struct v4l2_file_operations fm_drv_fops = {
485 	.owner = THIS_MODULE,
486 	.read = fm_v4l2_fops_read,
487 	.write = fm_v4l2_fops_write,
488 	.poll = fm_v4l2_fops_poll,
489 	.unlocked_ioctl = video_ioctl2,
490 	.open = fm_v4l2_fops_open,
491 	.release = fm_v4l2_fops_release,
492 };
493 
494 static const struct v4l2_ctrl_ops fm_ctrl_ops = {
495 	.s_ctrl = fm_v4l2_s_ctrl,
496 	.g_volatile_ctrl = fm_g_volatile_ctrl,
497 };
498 static const struct v4l2_ioctl_ops fm_drv_ioctl_ops = {
499 	.vidioc_querycap = fm_v4l2_vidioc_querycap,
500 	.vidioc_g_audio = fm_v4l2_vidioc_g_audio,
501 	.vidioc_s_audio = fm_v4l2_vidioc_s_audio,
502 	.vidioc_g_tuner = fm_v4l2_vidioc_g_tuner,
503 	.vidioc_s_tuner = fm_v4l2_vidioc_s_tuner,
504 	.vidioc_g_frequency = fm_v4l2_vidioc_g_freq,
505 	.vidioc_s_frequency = fm_v4l2_vidioc_s_freq,
506 	.vidioc_s_hw_freq_seek = fm_v4l2_vidioc_s_hw_freq_seek,
507 	.vidioc_g_modulator = fm_v4l2_vidioc_g_modulator,
508 	.vidioc_s_modulator = fm_v4l2_vidioc_s_modulator
509 };
510 
511 /* V4L2 RADIO device parent structure */
512 static const struct video_device fm_viddev_template = {
513 	.fops = &fm_drv_fops,
514 	.ioctl_ops = &fm_drv_ioctl_ops,
515 	.name = FM_DRV_NAME,
516 	.release = video_device_release_empty,
517 	/*
518 	 * To ensure both the tuner and modulator ioctls are accessible we
519 	 * set the vfl_dir to M2M to indicate this.
520 	 *
521 	 * It is not really a mem2mem device of course, but it can both receive
522 	 * and transmit using the same radio device. It's the only radio driver
523 	 * that does this and it should really be split in two radio devices,
524 	 * but that would affect applications using this driver.
525 	 */
526 	.vfl_dir = VFL_DIR_M2M,
527 };
528 
529 int fm_v4l2_init_video_device(struct fmdev *fmdev, int radio_nr)
530 {
531 	struct v4l2_ctrl *ctrl;
532 	int ret;
533 
534 	strlcpy(fmdev->v4l2_dev.name, FM_DRV_NAME, sizeof(fmdev->v4l2_dev.name));
535 	ret = v4l2_device_register(NULL, &fmdev->v4l2_dev);
536 	if (ret < 0)
537 		return ret;
538 
539 	/* Init mutex for core locking */
540 	mutex_init(&fmdev->mutex);
541 
542 	/* Setup FM driver's V4L2 properties */
543 	gradio_dev = fm_viddev_template;
544 
545 	video_set_drvdata(&gradio_dev, fmdev);
546 
547 	gradio_dev.lock = &fmdev->mutex;
548 	gradio_dev.v4l2_dev = &fmdev->v4l2_dev;
549 
550 	/* Register with V4L2 subsystem as RADIO device */
551 	if (video_register_device(&gradio_dev, VFL_TYPE_RADIO, radio_nr)) {
552 		fmerr("Could not register video device\n");
553 		return -ENOMEM;
554 	}
555 
556 	fmdev->radio_dev = &gradio_dev;
557 
558 	/* Register to v4l2 ctrl handler framework */
559 	fmdev->radio_dev->ctrl_handler = &fmdev->ctrl_handler;
560 
561 	ret = v4l2_ctrl_handler_init(&fmdev->ctrl_handler, 5);
562 	if (ret < 0) {
563 		fmerr("(fmdev): Can't init ctrl handler\n");
564 		v4l2_ctrl_handler_free(&fmdev->ctrl_handler);
565 		return -EBUSY;
566 	}
567 
568 	/*
569 	 * Following controls are handled by V4L2 control framework.
570 	 * Added in ascending ID order.
571 	 */
572 	v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
573 			V4L2_CID_AUDIO_VOLUME, FM_RX_VOLUME_MIN,
574 			FM_RX_VOLUME_MAX, 1, FM_RX_VOLUME_MAX);
575 
576 	v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
577 			V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
578 
579 	v4l2_ctrl_new_std_menu(&fmdev->ctrl_handler, &fm_ctrl_ops,
580 			V4L2_CID_TUNE_PREEMPHASIS, V4L2_PREEMPHASIS_75_uS,
581 			0, V4L2_PREEMPHASIS_75_uS);
582 
583 	v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
584 			V4L2_CID_TUNE_POWER_LEVEL, FM_PWR_LVL_LOW,
585 			FM_PWR_LVL_HIGH, 1, FM_PWR_LVL_HIGH);
586 
587 	ctrl = v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
588 			V4L2_CID_TUNE_ANTENNA_CAPACITOR, 0,
589 			255, 1, 255);
590 
591 	if (ctrl)
592 		ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;
593 
594 	return 0;
595 }
596 
597 void *fm_v4l2_deinit_video_device(void)
598 {
599 	struct fmdev *fmdev;
600 
601 
602 	fmdev = video_get_drvdata(&gradio_dev);
603 
604 	/* Unregister to v4l2 ctrl handler framework*/
605 	v4l2_ctrl_handler_free(&fmdev->ctrl_handler);
606 
607 	/* Unregister RADIO device from V4L2 subsystem */
608 	video_unregister_device(&gradio_dev);
609 
610 	v4l2_device_unregister(&fmdev->v4l2_dev);
611 
612 	return fmdev;
613 }
614