xref: /linux/drivers/media/radio/si470x/radio-si470x-usb.c (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
1 /*
2  *  drivers/media/radio/si470x/radio-si470x-usb.c
3  *
4  *  USB driver for radios with Silicon Labs Si470x FM Radio Receivers
5  *
6  *  Copyright (c) 2009 Tobias Lorenz <tobias.lorenz@gmx.net>
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 
19 
20 /*
21  * ToDo:
22  * - add firmware download/update support
23  */
24 
25 
26 /* driver definitions */
27 #define DRIVER_AUTHOR "Tobias Lorenz <tobias.lorenz@gmx.net>"
28 #define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver"
29 #define DRIVER_DESC "USB radio driver for Si470x FM Radio Receivers"
30 #define DRIVER_VERSION "1.0.10"
31 
32 /* kernel includes */
33 #include <linux/usb.h>
34 #include <linux/hid.h>
35 #include <linux/slab.h>
36 
37 #include "radio-si470x.h"
38 
39 
40 /* USB Device ID List */
41 static const struct usb_device_id si470x_usb_driver_id_table[] = {
42 	/* Silicon Labs USB FM Radio Reference Design */
43 	{ USB_DEVICE_AND_INTERFACE_INFO(0x10c4, 0x818a, USB_CLASS_HID, 0, 0) },
44 	/* ADS/Tech FM Radio Receiver (formerly Instant FM Music) */
45 	{ USB_DEVICE_AND_INTERFACE_INFO(0x06e1, 0xa155, USB_CLASS_HID, 0, 0) },
46 	/* KWorld USB FM Radio SnapMusic Mobile 700 (FM700) */
47 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1b80, 0xd700, USB_CLASS_HID, 0, 0) },
48 	/* Sanei Electric, Inc. FM USB Radio (sold as DealExtreme.com PCear) */
49 	{ USB_DEVICE_AND_INTERFACE_INFO(0x10c5, 0x819a, USB_CLASS_HID, 0, 0) },
50 	/* Axentia ALERT FM USB Receiver */
51 	{ USB_DEVICE_AND_INTERFACE_INFO(0x12cf, 0x7111, USB_CLASS_HID, 0, 0) },
52 	/* Terminating entry */
53 	{ }
54 };
55 MODULE_DEVICE_TABLE(usb, si470x_usb_driver_id_table);
56 
57 
58 
59 /**************************************************************************
60  * Module Parameters
61  **************************************************************************/
62 
63 /* Radio Nr */
64 static int radio_nr = -1;
65 module_param(radio_nr, int, 0444);
66 MODULE_PARM_DESC(radio_nr, "Radio Nr");
67 
68 /* USB timeout */
69 static unsigned int usb_timeout = 500;
70 module_param(usb_timeout, uint, 0644);
71 MODULE_PARM_DESC(usb_timeout, "USB timeout (ms): *500*");
72 
73 /* RDS buffer blocks */
74 static unsigned int rds_buf = 100;
75 module_param(rds_buf, uint, 0444);
76 MODULE_PARM_DESC(rds_buf, "RDS buffer entries: *100*");
77 
78 /* RDS maximum block errors */
79 static unsigned short max_rds_errors = 1;
80 /* 0 means   0  errors requiring correction */
81 /* 1 means 1-2  errors requiring correction (used by original USBRadio.exe) */
82 /* 2 means 3-5  errors requiring correction */
83 /* 3 means   6+ errors or errors in checkword, correction not possible */
84 module_param(max_rds_errors, ushort, 0644);
85 MODULE_PARM_DESC(max_rds_errors, "RDS maximum block errors: *1*");
86 
87 
88 
89 /**************************************************************************
90  * USB HID Reports
91  **************************************************************************/
92 
93 /* Reports 1-16 give direct read/write access to the 16 Si470x registers */
94 /* with the (REPORT_ID - 1) corresponding to the register address across USB */
95 /* endpoint 0 using GET_REPORT and SET_REPORT */
96 #define REGISTER_REPORT_SIZE	(RADIO_REGISTER_SIZE + 1)
97 #define REGISTER_REPORT(reg)	((reg) + 1)
98 
99 /* Report 17 gives direct read/write access to the entire Si470x register */
100 /* map across endpoint 0 using GET_REPORT and SET_REPORT */
101 #define ENTIRE_REPORT_SIZE	(RADIO_REGISTER_NUM * RADIO_REGISTER_SIZE + 1)
102 #define ENTIRE_REPORT		17
103 
104 /* Report 18 is used to send the lowest 6 Si470x registers up the HID */
105 /* interrupt endpoint 1 to Windows every 20 milliseconds for status */
106 #define RDS_REPORT_SIZE		(RDS_REGISTER_NUM * RADIO_REGISTER_SIZE + 1)
107 #define RDS_REPORT		18
108 
109 /* Report 19: LED state */
110 #define LED_REPORT_SIZE		3
111 #define LED_REPORT		19
112 
113 /* Report 19: stream */
114 #define STREAM_REPORT_SIZE	3
115 #define STREAM_REPORT		19
116 
117 /* Report 20: scratch */
118 #define SCRATCH_PAGE_SIZE	63
119 #define SCRATCH_REPORT_SIZE	(SCRATCH_PAGE_SIZE + 1)
120 #define SCRATCH_REPORT		20
121 
122 /* Reports 19-22: flash upgrade of the C8051F321 */
123 #define WRITE_REPORT_SIZE	4
124 #define WRITE_REPORT		19
125 #define FLASH_REPORT_SIZE	64
126 #define FLASH_REPORT		20
127 #define CRC_REPORT_SIZE		3
128 #define CRC_REPORT		21
129 #define RESPONSE_REPORT_SIZE	2
130 #define RESPONSE_REPORT		22
131 
132 /* Report 23: currently unused, but can accept 60 byte reports on the HID */
133 /* interrupt out endpoint 2 every 1 millisecond */
134 #define UNUSED_REPORT		23
135 
136 #define MAX_REPORT_SIZE		64
137 
138 
139 
140 /**************************************************************************
141  * Software/Hardware Versions from Scratch Page
142  **************************************************************************/
143 #define RADIO_HW_VERSION			1
144 
145 
146 
147 /**************************************************************************
148  * LED State Definitions
149  **************************************************************************/
150 #define LED_COMMAND		0x35
151 
152 #define NO_CHANGE_LED		0x00
153 #define ALL_COLOR_LED		0x01	/* streaming state */
154 #define BLINK_GREEN_LED		0x02	/* connect state */
155 #define BLINK_RED_LED		0x04
156 #define BLINK_ORANGE_LED	0x10	/* disconnect state */
157 #define SOLID_GREEN_LED		0x20	/* tuning/seeking state */
158 #define SOLID_RED_LED		0x40	/* bootload state */
159 #define SOLID_ORANGE_LED	0x80
160 
161 
162 
163 /**************************************************************************
164  * Stream State Definitions
165  **************************************************************************/
166 #define STREAM_COMMAND	0x36
167 #define STREAM_VIDPID	0x00
168 #define STREAM_AUDIO	0xff
169 
170 
171 
172 /**************************************************************************
173  * Bootloader / Flash Commands
174  **************************************************************************/
175 
176 /* unique id sent to bootloader and required to put into a bootload state */
177 #define UNIQUE_BL_ID		0x34
178 
179 /* mask for the flash data */
180 #define FLASH_DATA_MASK		0x55
181 
182 /* bootloader commands */
183 #define GET_SW_VERSION_COMMAND	0x00
184 #define SET_PAGE_COMMAND	0x01
185 #define ERASE_PAGE_COMMAND	0x02
186 #define WRITE_PAGE_COMMAND	0x03
187 #define CRC_ON_PAGE_COMMAND	0x04
188 #define READ_FLASH_BYTE_COMMAND	0x05
189 #define RESET_DEVICE_COMMAND	0x06
190 #define GET_HW_VERSION_COMMAND	0x07
191 #define BLANK			0xff
192 
193 /* bootloader command responses */
194 #define COMMAND_OK		0x01
195 #define COMMAND_FAILED		0x02
196 #define COMMAND_PENDING		0x03
197 
198 
199 
200 /**************************************************************************
201  * General Driver Functions - REGISTER_REPORTs
202  **************************************************************************/
203 
204 /*
205  * si470x_get_report - receive a HID report
206  */
207 static int si470x_get_report(struct si470x_device *radio, void *buf, int size)
208 {
209 	unsigned char *report = buf;
210 	int retval;
211 
212 	retval = usb_control_msg(radio->usbdev,
213 		usb_rcvctrlpipe(radio->usbdev, 0),
214 		HID_REQ_GET_REPORT,
215 		USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
216 		report[0], 2,
217 		buf, size, usb_timeout);
218 
219 	if (retval < 0)
220 		dev_warn(&radio->intf->dev,
221 			"si470x_get_report: usb_control_msg returned %d\n",
222 			retval);
223 	return retval;
224 }
225 
226 
227 /*
228  * si470x_set_report - send a HID report
229  */
230 static int si470x_set_report(struct si470x_device *radio, void *buf, int size)
231 {
232 	unsigned char *report = buf;
233 	int retval;
234 
235 	retval = usb_control_msg(radio->usbdev,
236 		usb_sndctrlpipe(radio->usbdev, 0),
237 		HID_REQ_SET_REPORT,
238 		USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
239 		report[0], 2,
240 		buf, size, usb_timeout);
241 
242 	if (retval < 0)
243 		dev_warn(&radio->intf->dev,
244 			"si470x_set_report: usb_control_msg returned %d\n",
245 			retval);
246 	return retval;
247 }
248 
249 
250 /*
251  * si470x_get_register - read register
252  */
253 static int si470x_get_register(struct si470x_device *radio, int regnr)
254 {
255 	int retval;
256 
257 	radio->usb_buf[0] = REGISTER_REPORT(regnr);
258 
259 	retval = si470x_get_report(radio, radio->usb_buf, REGISTER_REPORT_SIZE);
260 
261 	if (retval >= 0)
262 		radio->registers[regnr] = get_unaligned_be16(&radio->usb_buf[1]);
263 
264 	return (retval < 0) ? -EINVAL : 0;
265 }
266 
267 
268 /*
269  * si470x_set_register - write register
270  */
271 static int si470x_set_register(struct si470x_device *radio, int regnr)
272 {
273 	int retval;
274 
275 	radio->usb_buf[0] = REGISTER_REPORT(regnr);
276 	put_unaligned_be16(radio->registers[regnr], &radio->usb_buf[1]);
277 
278 	retval = si470x_set_report(radio, radio->usb_buf, REGISTER_REPORT_SIZE);
279 
280 	return (retval < 0) ? -EINVAL : 0;
281 }
282 
283 
284 
285 /**************************************************************************
286  * General Driver Functions - ENTIRE_REPORT
287  **************************************************************************/
288 
289 /*
290  * si470x_get_all_registers - read entire registers
291  */
292 static int si470x_get_all_registers(struct si470x_device *radio)
293 {
294 	int retval;
295 	unsigned char regnr;
296 
297 	radio->usb_buf[0] = ENTIRE_REPORT;
298 
299 	retval = si470x_get_report(radio, radio->usb_buf, ENTIRE_REPORT_SIZE);
300 
301 	if (retval >= 0)
302 		for (regnr = 0; regnr < RADIO_REGISTER_NUM; regnr++)
303 			radio->registers[regnr] = get_unaligned_be16(
304 				&radio->usb_buf[regnr * RADIO_REGISTER_SIZE + 1]);
305 
306 	return (retval < 0) ? -EINVAL : 0;
307 }
308 
309 
310 
311 /**************************************************************************
312  * General Driver Functions - LED_REPORT
313  **************************************************************************/
314 
315 /*
316  * si470x_set_led_state - sets the led state
317  */
318 static int si470x_set_led_state(struct si470x_device *radio,
319 		unsigned char led_state)
320 {
321 	int retval;
322 
323 	radio->usb_buf[0] = LED_REPORT;
324 	radio->usb_buf[1] = LED_COMMAND;
325 	radio->usb_buf[2] = led_state;
326 
327 	retval = si470x_set_report(radio, radio->usb_buf, LED_REPORT_SIZE);
328 
329 	return (retval < 0) ? -EINVAL : 0;
330 }
331 
332 
333 
334 /**************************************************************************
335  * General Driver Functions - SCRATCH_REPORT
336  **************************************************************************/
337 
338 /*
339  * si470x_get_scratch_versions - gets the scratch page and version infos
340  */
341 static int si470x_get_scratch_page_versions(struct si470x_device *radio)
342 {
343 	int retval;
344 
345 	radio->usb_buf[0] = SCRATCH_REPORT;
346 
347 	retval = si470x_get_report(radio, radio->usb_buf, SCRATCH_REPORT_SIZE);
348 
349 	if (retval < 0)
350 		dev_warn(&radio->intf->dev, "si470x_get_scratch: si470x_get_report returned %d\n",
351 			 retval);
352 	else {
353 		radio->software_version = radio->usb_buf[1];
354 		radio->hardware_version = radio->usb_buf[2];
355 	}
356 
357 	return (retval < 0) ? -EINVAL : 0;
358 }
359 
360 
361 
362 /**************************************************************************
363  * RDS Driver Functions
364  **************************************************************************/
365 
366 /*
367  * si470x_int_in_callback - rds callback and processing function
368  *
369  * TODO: do we need to use mutex locks in some sections?
370  */
371 static void si470x_int_in_callback(struct urb *urb)
372 {
373 	struct si470x_device *radio = urb->context;
374 	int retval;
375 	unsigned char regnr;
376 	unsigned char blocknum;
377 	unsigned short bler; /* rds block errors */
378 	unsigned short rds;
379 	unsigned char tmpbuf[3];
380 
381 	if (urb->status) {
382 		if (urb->status == -ENOENT ||
383 				urb->status == -ECONNRESET ||
384 				urb->status == -ESHUTDOWN) {
385 			return;
386 		} else {
387 			dev_warn(&radio->intf->dev,
388 			 "non-zero urb status (%d)\n", urb->status);
389 			goto resubmit; /* Maybe we can recover. */
390 		}
391 	}
392 
393 	/* Sometimes the device returns len 0 packets */
394 	if (urb->actual_length != RDS_REPORT_SIZE)
395 		goto resubmit;
396 
397 	radio->registers[STATUSRSSI] =
398 		get_unaligned_be16(&radio->int_in_buffer[1]);
399 
400 	if (radio->registers[STATUSRSSI] & STATUSRSSI_STC)
401 		complete(&radio->completion);
402 
403 	if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS)) {
404 		/* Update RDS registers with URB data */
405 		for (regnr = 1; regnr < RDS_REGISTER_NUM; regnr++)
406 			radio->registers[STATUSRSSI + regnr] =
407 			    get_unaligned_be16(&radio->int_in_buffer[
408 				regnr * RADIO_REGISTER_SIZE + 1]);
409 		/* get rds blocks */
410 		if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSR) == 0) {
411 			/* No RDS group ready, better luck next time */
412 			goto resubmit;
413 		}
414 		if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSS) == 0) {
415 			/* RDS decoder not synchronized */
416 			goto resubmit;
417 		}
418 		for (blocknum = 0; blocknum < 4; blocknum++) {
419 			switch (blocknum) {
420 			default:
421 				bler = (radio->registers[STATUSRSSI] &
422 						STATUSRSSI_BLERA) >> 9;
423 				rds = radio->registers[RDSA];
424 				break;
425 			case 1:
426 				bler = (radio->registers[READCHAN] &
427 						READCHAN_BLERB) >> 14;
428 				rds = radio->registers[RDSB];
429 				break;
430 			case 2:
431 				bler = (radio->registers[READCHAN] &
432 						READCHAN_BLERC) >> 12;
433 				rds = radio->registers[RDSC];
434 				break;
435 			case 3:
436 				bler = (radio->registers[READCHAN] &
437 						READCHAN_BLERD) >> 10;
438 				rds = radio->registers[RDSD];
439 				break;
440 			}
441 
442 			/* Fill the V4L2 RDS buffer */
443 			put_unaligned_le16(rds, &tmpbuf);
444 			tmpbuf[2] = blocknum;		/* offset name */
445 			tmpbuf[2] |= blocknum << 3;	/* received offset */
446 			if (bler > max_rds_errors)
447 				tmpbuf[2] |= 0x80; /* uncorrectable errors */
448 			else if (bler > 0)
449 				tmpbuf[2] |= 0x40; /* corrected error(s) */
450 
451 			/* copy RDS block to internal buffer */
452 			memcpy(&radio->buffer[radio->wr_index], &tmpbuf, 3);
453 			radio->wr_index += 3;
454 
455 			/* wrap write pointer */
456 			if (radio->wr_index >= radio->buf_size)
457 				radio->wr_index = 0;
458 
459 			/* check for overflow */
460 			if (radio->wr_index == radio->rd_index) {
461 				/* increment and wrap read pointer */
462 				radio->rd_index += 3;
463 				if (radio->rd_index >= radio->buf_size)
464 					radio->rd_index = 0;
465 			}
466 		}
467 		if (radio->wr_index != radio->rd_index)
468 			wake_up_interruptible(&radio->read_queue);
469 	}
470 
471 resubmit:
472 	/* Resubmit if we're still running. */
473 	if (radio->int_in_running && radio->usbdev) {
474 		retval = usb_submit_urb(radio->int_in_urb, GFP_ATOMIC);
475 		if (retval) {
476 			dev_warn(&radio->intf->dev,
477 			       "resubmitting urb failed (%d)", retval);
478 			radio->int_in_running = 0;
479 		}
480 	}
481 	radio->status_rssi_auto_update = radio->int_in_running;
482 }
483 
484 
485 static int si470x_fops_open(struct file *file)
486 {
487 	return v4l2_fh_open(file);
488 }
489 
490 static int si470x_fops_release(struct file *file)
491 {
492 	return v4l2_fh_release(file);
493 }
494 
495 static void si470x_usb_release(struct v4l2_device *v4l2_dev)
496 {
497 	struct si470x_device *radio =
498 		container_of(v4l2_dev, struct si470x_device, v4l2_dev);
499 
500 	usb_free_urb(radio->int_in_urb);
501 	v4l2_ctrl_handler_free(&radio->hdl);
502 	v4l2_device_unregister(&radio->v4l2_dev);
503 	kfree(radio->int_in_buffer);
504 	kfree(radio->buffer);
505 	kfree(radio->usb_buf);
506 	kfree(radio);
507 }
508 
509 
510 /**************************************************************************
511  * Video4Linux Interface
512  **************************************************************************/
513 
514 /*
515  * si470x_vidioc_querycap - query device capabilities
516  */
517 static int si470x_vidioc_querycap(struct file *file, void *priv,
518 				  struct v4l2_capability *capability)
519 {
520 	struct si470x_device *radio = video_drvdata(file);
521 
522 	strlcpy(capability->driver, DRIVER_NAME, sizeof(capability->driver));
523 	strlcpy(capability->card, DRIVER_CARD, sizeof(capability->card));
524 	usb_make_path(radio->usbdev, capability->bus_info,
525 			sizeof(capability->bus_info));
526 	capability->device_caps = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_READWRITE |
527 		V4L2_CAP_TUNER | V4L2_CAP_RADIO | V4L2_CAP_RDS_CAPTURE;
528 	capability->capabilities = capability->device_caps | V4L2_CAP_DEVICE_CAPS;
529 	return 0;
530 }
531 
532 
533 static int si470x_start_usb(struct si470x_device *radio)
534 {
535 	int retval;
536 
537 	/* initialize interrupt urb */
538 	usb_fill_int_urb(radio->int_in_urb, radio->usbdev,
539 			usb_rcvintpipe(radio->usbdev,
540 				radio->int_in_endpoint->bEndpointAddress),
541 			radio->int_in_buffer,
542 			le16_to_cpu(radio->int_in_endpoint->wMaxPacketSize),
543 			si470x_int_in_callback,
544 			radio,
545 			radio->int_in_endpoint->bInterval);
546 
547 	radio->int_in_running = 1;
548 	mb();
549 
550 	retval = usb_submit_urb(radio->int_in_urb, GFP_KERNEL);
551 	if (retval) {
552 		dev_info(&radio->intf->dev,
553 				"submitting int urb failed (%d)\n", retval);
554 		radio->int_in_running = 0;
555 	}
556 	radio->status_rssi_auto_update = radio->int_in_running;
557 
558 	/* start radio */
559 	retval = si470x_start(radio);
560 	if (retval < 0)
561 		return retval;
562 
563 	v4l2_ctrl_handler_setup(&radio->hdl);
564 
565 	return retval;
566 }
567 
568 /**************************************************************************
569  * USB Interface
570  **************************************************************************/
571 
572 /*
573  * si470x_usb_driver_probe - probe for the device
574  */
575 static int si470x_usb_driver_probe(struct usb_interface *intf,
576 		const struct usb_device_id *id)
577 {
578 	struct si470x_device *radio;
579 	struct usb_host_interface *iface_desc;
580 	struct usb_endpoint_descriptor *endpoint;
581 	int i, int_end_size, retval;
582 	unsigned char version_warning = 0;
583 
584 	/* private data allocation and initialization */
585 	radio = kzalloc(sizeof(struct si470x_device), GFP_KERNEL);
586 	if (!radio) {
587 		retval = -ENOMEM;
588 		goto err_initial;
589 	}
590 	radio->usb_buf = kmalloc(MAX_REPORT_SIZE, GFP_KERNEL);
591 	if (radio->usb_buf == NULL) {
592 		retval = -ENOMEM;
593 		goto err_radio;
594 	}
595 	radio->usbdev = interface_to_usbdev(intf);
596 	radio->intf = intf;
597 	radio->band = 1; /* Default to 76 - 108 MHz */
598 	mutex_init(&radio->lock);
599 	init_completion(&radio->completion);
600 
601 	radio->get_register = si470x_get_register;
602 	radio->set_register = si470x_set_register;
603 	radio->fops_open = si470x_fops_open;
604 	radio->fops_release = si470x_fops_release;
605 	radio->vidioc_querycap = si470x_vidioc_querycap;
606 
607 	iface_desc = intf->cur_altsetting;
608 
609 	/* Set up interrupt endpoint information. */
610 	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
611 		endpoint = &iface_desc->endpoint[i].desc;
612 		if (usb_endpoint_is_int_in(endpoint))
613 			radio->int_in_endpoint = endpoint;
614 	}
615 	if (!radio->int_in_endpoint) {
616 		dev_info(&intf->dev, "could not find interrupt in endpoint\n");
617 		retval = -EIO;
618 		goto err_usbbuf;
619 	}
620 
621 	int_end_size = le16_to_cpu(radio->int_in_endpoint->wMaxPacketSize);
622 
623 	radio->int_in_buffer = kmalloc(int_end_size, GFP_KERNEL);
624 	if (!radio->int_in_buffer) {
625 		dev_info(&intf->dev, "could not allocate int_in_buffer");
626 		retval = -ENOMEM;
627 		goto err_usbbuf;
628 	}
629 
630 	radio->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
631 	if (!radio->int_in_urb) {
632 		retval = -ENOMEM;
633 		goto err_intbuffer;
634 	}
635 
636 	radio->v4l2_dev.release = si470x_usb_release;
637 
638 	/*
639 	 * The si470x SiLabs reference design uses the same USB IDs as
640 	 * 'Thanko's Raremono' si4734 based receiver. So check here which we
641 	 * have: attempt to read the device ID from the si470x: the lower 12
642 	 * bits should be 0x0242 for the si470x.
643 	 *
644 	 * We use this check to determine which device we are dealing with.
645 	 */
646 	if (id->idVendor == 0x10c4 && id->idProduct == 0x818a) {
647 		retval = usb_control_msg(radio->usbdev,
648 				usb_rcvctrlpipe(radio->usbdev, 0),
649 				HID_REQ_GET_REPORT,
650 				USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
651 				1, 2,
652 				radio->usb_buf, 3, 500);
653 		if (retval != 3 ||
654 		    (get_unaligned_be16(&radio->usb_buf[1]) & 0xfff) != 0x0242) {
655 			dev_info(&intf->dev, "this is not a si470x device.\n");
656 			retval = -ENODEV;
657 			goto err_urb;
658 		}
659 	}
660 
661 	retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
662 	if (retval < 0) {
663 		dev_err(&intf->dev, "couldn't register v4l2_device\n");
664 		goto err_urb;
665 	}
666 
667 	v4l2_ctrl_handler_init(&radio->hdl, 2);
668 	v4l2_ctrl_new_std(&radio->hdl, &si470x_ctrl_ops,
669 			  V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
670 	v4l2_ctrl_new_std(&radio->hdl, &si470x_ctrl_ops,
671 			  V4L2_CID_AUDIO_VOLUME, 0, 15, 1, 15);
672 	if (radio->hdl.error) {
673 		retval = radio->hdl.error;
674 		dev_err(&intf->dev, "couldn't register control\n");
675 		goto err_dev;
676 	}
677 	radio->videodev = si470x_viddev_template;
678 	radio->videodev.ctrl_handler = &radio->hdl;
679 	radio->videodev.lock = &radio->lock;
680 	radio->videodev.v4l2_dev = &radio->v4l2_dev;
681 	radio->videodev.release = video_device_release_empty;
682 	video_set_drvdata(&radio->videodev, radio);
683 
684 	/* get device and chip versions */
685 	if (si470x_get_all_registers(radio) < 0) {
686 		retval = -EIO;
687 		goto err_ctrl;
688 	}
689 	dev_info(&intf->dev, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
690 			radio->registers[DEVICEID], radio->registers[SI_CHIPID]);
691 	if ((radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE) < RADIO_FW_VERSION) {
692 		dev_warn(&intf->dev,
693 			"This driver is known to work with firmware version %hu,\n",
694 			RADIO_FW_VERSION);
695 		dev_warn(&intf->dev,
696 			"but the device has firmware version %hu.\n",
697 			radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE);
698 		version_warning = 1;
699 	}
700 
701 	/* get software and hardware versions */
702 	if (si470x_get_scratch_page_versions(radio) < 0) {
703 		retval = -EIO;
704 		goto err_ctrl;
705 	}
706 	dev_info(&intf->dev, "software version %d, hardware version %d\n",
707 			radio->software_version, radio->hardware_version);
708 	if (radio->hardware_version < RADIO_HW_VERSION) {
709 		dev_warn(&intf->dev,
710 			"This driver is known to work with hardware version %hu,\n",
711 			RADIO_HW_VERSION);
712 		dev_warn(&intf->dev,
713 			"but the device has hardware version %hu.\n",
714 			radio->hardware_version);
715 		version_warning = 1;
716 	}
717 
718 	/* give out version warning */
719 	if (version_warning == 1) {
720 		dev_warn(&intf->dev,
721 			"If you have some trouble using this driver,\n");
722 		dev_warn(&intf->dev,
723 			"please report to V4L ML at linux-media@vger.kernel.org\n");
724 	}
725 
726 	/* set led to connect state */
727 	si470x_set_led_state(radio, BLINK_GREEN_LED);
728 
729 	/* rds buffer allocation */
730 	radio->buf_size = rds_buf * 3;
731 	radio->buffer = kmalloc(radio->buf_size, GFP_KERNEL);
732 	if (!radio->buffer) {
733 		retval = -EIO;
734 		goto err_ctrl;
735 	}
736 
737 	/* rds buffer configuration */
738 	radio->wr_index = 0;
739 	radio->rd_index = 0;
740 	init_waitqueue_head(&radio->read_queue);
741 	usb_set_intfdata(intf, radio);
742 
743 	/* start radio */
744 	retval = si470x_start_usb(radio);
745 	if (retval < 0)
746 		goto err_all;
747 
748 	/* set initial frequency */
749 	si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */
750 
751 	/* register video device */
752 	retval = video_register_device(&radio->videodev, VFL_TYPE_RADIO,
753 			radio_nr);
754 	if (retval) {
755 		dev_err(&intf->dev, "Could not register video device\n");
756 		goto err_all;
757 	}
758 
759 	return 0;
760 err_all:
761 	kfree(radio->buffer);
762 err_ctrl:
763 	v4l2_ctrl_handler_free(&radio->hdl);
764 err_dev:
765 	v4l2_device_unregister(&radio->v4l2_dev);
766 err_urb:
767 	usb_free_urb(radio->int_in_urb);
768 err_intbuffer:
769 	kfree(radio->int_in_buffer);
770 err_usbbuf:
771 	kfree(radio->usb_buf);
772 err_radio:
773 	kfree(radio);
774 err_initial:
775 	return retval;
776 }
777 
778 
779 /*
780  * si470x_usb_driver_suspend - suspend the device
781  */
782 static int si470x_usb_driver_suspend(struct usb_interface *intf,
783 		pm_message_t message)
784 {
785 	struct si470x_device *radio = usb_get_intfdata(intf);
786 
787 	dev_info(&intf->dev, "suspending now...\n");
788 
789 	/* shutdown interrupt handler */
790 	if (radio->int_in_running) {
791 		radio->int_in_running = 0;
792 		if (radio->int_in_urb)
793 			usb_kill_urb(radio->int_in_urb);
794 	}
795 
796 	/* cancel read processes */
797 	wake_up_interruptible(&radio->read_queue);
798 
799 	/* stop radio */
800 	si470x_stop(radio);
801 	return 0;
802 }
803 
804 
805 /*
806  * si470x_usb_driver_resume - resume the device
807  */
808 static int si470x_usb_driver_resume(struct usb_interface *intf)
809 {
810 	struct si470x_device *radio = usb_get_intfdata(intf);
811 	int ret;
812 
813 	dev_info(&intf->dev, "resuming now...\n");
814 
815 	/* start radio */
816 	ret = si470x_start_usb(radio);
817 	if (ret == 0)
818 		v4l2_ctrl_handler_setup(&radio->hdl);
819 
820 	return ret;
821 }
822 
823 
824 /*
825  * si470x_usb_driver_disconnect - disconnect the device
826  */
827 static void si470x_usb_driver_disconnect(struct usb_interface *intf)
828 {
829 	struct si470x_device *radio = usb_get_intfdata(intf);
830 
831 	mutex_lock(&radio->lock);
832 	v4l2_device_disconnect(&radio->v4l2_dev);
833 	video_unregister_device(&radio->videodev);
834 	usb_set_intfdata(intf, NULL);
835 	mutex_unlock(&radio->lock);
836 	v4l2_device_put(&radio->v4l2_dev);
837 }
838 
839 
840 /*
841  * si470x_usb_driver - usb driver interface
842  *
843  * A note on suspend/resume: this driver had only empty suspend/resume
844  * functions, and when I tried to test suspend/resume it always disconnected
845  * instead of resuming (using my ADS InstantFM stick). So I've decided to
846  * remove these callbacks until someone else with better hardware can
847  * implement and test this.
848  */
849 static struct usb_driver si470x_usb_driver = {
850 	.name			= DRIVER_NAME,
851 	.probe			= si470x_usb_driver_probe,
852 	.disconnect		= si470x_usb_driver_disconnect,
853 	.suspend		= si470x_usb_driver_suspend,
854 	.resume			= si470x_usb_driver_resume,
855 	.reset_resume		= si470x_usb_driver_resume,
856 	.id_table		= si470x_usb_driver_id_table,
857 };
858 
859 module_usb_driver(si470x_usb_driver);
860 
861 MODULE_LICENSE("GPL");
862 MODULE_AUTHOR(DRIVER_AUTHOR);
863 MODULE_DESCRIPTION(DRIVER_DESC);
864 MODULE_VERSION(DRIVER_VERSION);
865