1 /*
2  * Linux V4L2 radio driver for the Griffin radioSHARK USB radio receiver
3  *
4  * Note the radioSHARK offers the audio through a regular USB audio device,
5  * this driver only handles the tuning.
6  *
7  * The info necessary to drive the shark was taken from the small userspace
8  * shark.c program by Michael Rolig, which he kindly placed in the Public
9  * Domain.
10  *
11  * Copyright (c) 2012 Hans de Goede <hdegoede@redhat.com>
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22 */
23 
24 #include <linux/init.h>
25 #include <linux/kernel.h>
26 #include <linux/leds.h>
27 #include <linux/module.h>
28 #include <linux/slab.h>
29 #include <linux/usb.h>
30 #include <linux/workqueue.h>
31 #include <media/v4l2-device.h>
32 #include <media/drv-intf/tea575x.h>
33 
34 #if defined(CONFIG_LEDS_CLASS) || \
35     (defined(CONFIG_LEDS_CLASS_MODULE) && defined(CONFIG_RADIO_SHARK_MODULE))
36 #define SHARK_USE_LEDS 1
37 #endif
38 
39 /*
40  * Version Information
41  */
42 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
43 MODULE_DESCRIPTION("Griffin radioSHARK, USB radio receiver driver");
44 MODULE_LICENSE("GPL");
45 
46 #define SHARK_IN_EP		0x83
47 #define SHARK_OUT_EP		0x05
48 
49 #define TEA575X_BIT_MONO	(1<<22)		/* 0 = stereo, 1 = mono */
50 #define TEA575X_BIT_BAND_MASK	(3<<20)
51 #define TEA575X_BIT_BAND_FM	(0<<20)
52 
53 #define TB_LEN 6
54 #define DRV_NAME "radioshark"
55 
56 #define v4l2_dev_to_shark(d) container_of(d, struct shark_device, v4l2_dev)
57 
58 /* Note BLUE_IS_PULSE comes after NO_LEDS as it is a status bit, not a LED */
59 enum { BLUE_LED, BLUE_PULSE_LED, RED_LED, NO_LEDS, BLUE_IS_PULSE };
60 
61 struct shark_device {
62 	struct usb_device *usbdev;
63 	struct v4l2_device v4l2_dev;
64 	struct snd_tea575x tea;
65 
66 #ifdef SHARK_USE_LEDS
67 	struct work_struct led_work;
68 	struct led_classdev leds[NO_LEDS];
69 	char led_names[NO_LEDS][32];
70 	atomic_t brightness[NO_LEDS];
71 	unsigned long brightness_new;
72 #endif
73 
74 	u8 *transfer_buffer;
75 	u32 last_val;
76 };
77 
78 static atomic_t shark_instance = ATOMIC_INIT(0);
79 
80 static void shark_write_val(struct snd_tea575x *tea, u32 val)
81 {
82 	struct shark_device *shark = tea->private_data;
83 	int i, res, actual_len;
84 
85 	/* Avoid unnecessary (slow) USB transfers */
86 	if (shark->last_val == val)
87 		return;
88 
89 	memset(shark->transfer_buffer, 0, TB_LEN);
90 	shark->transfer_buffer[0] = 0xc0; /* Write shift register command */
91 	for (i = 0; i < 4; i++)
92 		shark->transfer_buffer[i] |= (val >> (24 - i * 8)) & 0xff;
93 
94 	res = usb_interrupt_msg(shark->usbdev,
95 				usb_sndintpipe(shark->usbdev, SHARK_OUT_EP),
96 				shark->transfer_buffer, TB_LEN,
97 				&actual_len, 1000);
98 	if (res >= 0)
99 		shark->last_val = val;
100 	else
101 		v4l2_err(&shark->v4l2_dev, "set-freq error: %d\n", res);
102 }
103 
104 static u32 shark_read_val(struct snd_tea575x *tea)
105 {
106 	struct shark_device *shark = tea->private_data;
107 	int i, res, actual_len;
108 	u32 val = 0;
109 
110 	memset(shark->transfer_buffer, 0, TB_LEN);
111 	shark->transfer_buffer[0] = 0x80;
112 	res = usb_interrupt_msg(shark->usbdev,
113 				usb_sndintpipe(shark->usbdev, SHARK_OUT_EP),
114 				shark->transfer_buffer, TB_LEN,
115 				&actual_len, 1000);
116 	if (res < 0) {
117 		v4l2_err(&shark->v4l2_dev, "request-status error: %d\n", res);
118 		return shark->last_val;
119 	}
120 
121 	res = usb_interrupt_msg(shark->usbdev,
122 				usb_rcvintpipe(shark->usbdev, SHARK_IN_EP),
123 				shark->transfer_buffer, TB_LEN,
124 				&actual_len, 1000);
125 	if (res < 0) {
126 		v4l2_err(&shark->v4l2_dev, "get-status error: %d\n", res);
127 		return shark->last_val;
128 	}
129 
130 	for (i = 0; i < 4; i++)
131 		val |= shark->transfer_buffer[i] << (24 - i * 8);
132 
133 	shark->last_val = val;
134 
135 	/*
136 	 * The shark does not allow actually reading the stereo / mono pin :(
137 	 * So assume that when we're tuned to an FM station and mono has not
138 	 * been requested, that we're receiving stereo.
139 	 */
140 	if (((val & TEA575X_BIT_BAND_MASK) == TEA575X_BIT_BAND_FM) &&
141 	    !(val & TEA575X_BIT_MONO))
142 		shark->tea.stereo = true;
143 	else
144 		shark->tea.stereo = false;
145 
146 	return val;
147 }
148 
149 static const struct snd_tea575x_ops shark_tea_ops = {
150 	.write_val = shark_write_val,
151 	.read_val  = shark_read_val,
152 };
153 
154 #ifdef SHARK_USE_LEDS
155 static void shark_led_work(struct work_struct *work)
156 {
157 	struct shark_device *shark =
158 		container_of(work, struct shark_device, led_work);
159 	int i, res, brightness, actual_len;
160 
161 	for (i = 0; i < 3; i++) {
162 		if (!test_and_clear_bit(i, &shark->brightness_new))
163 			continue;
164 
165 		brightness = atomic_read(&shark->brightness[i]);
166 		memset(shark->transfer_buffer, 0, TB_LEN);
167 		if (i != RED_LED) {
168 			shark->transfer_buffer[0] = 0xA0 + i;
169 			shark->transfer_buffer[1] = brightness;
170 		} else
171 			shark->transfer_buffer[0] = brightness ? 0xA9 : 0xA8;
172 		res = usb_interrupt_msg(shark->usbdev,
173 					usb_sndintpipe(shark->usbdev, 0x05),
174 					shark->transfer_buffer, TB_LEN,
175 					&actual_len, 1000);
176 		if (res < 0)
177 			v4l2_err(&shark->v4l2_dev, "set LED %s error: %d\n",
178 				 shark->led_names[i], res);
179 	}
180 }
181 
182 static void shark_led_set_blue(struct led_classdev *led_cdev,
183 			       enum led_brightness value)
184 {
185 	struct shark_device *shark =
186 		container_of(led_cdev, struct shark_device, leds[BLUE_LED]);
187 
188 	atomic_set(&shark->brightness[BLUE_LED], value);
189 	set_bit(BLUE_LED, &shark->brightness_new);
190 	clear_bit(BLUE_IS_PULSE, &shark->brightness_new);
191 	schedule_work(&shark->led_work);
192 }
193 
194 static void shark_led_set_blue_pulse(struct led_classdev *led_cdev,
195 				     enum led_brightness value)
196 {
197 	struct shark_device *shark = container_of(led_cdev,
198 				struct shark_device, leds[BLUE_PULSE_LED]);
199 
200 	atomic_set(&shark->brightness[BLUE_PULSE_LED], 256 - value);
201 	set_bit(BLUE_PULSE_LED, &shark->brightness_new);
202 	set_bit(BLUE_IS_PULSE, &shark->brightness_new);
203 	schedule_work(&shark->led_work);
204 }
205 
206 static void shark_led_set_red(struct led_classdev *led_cdev,
207 			      enum led_brightness value)
208 {
209 	struct shark_device *shark =
210 		container_of(led_cdev, struct shark_device, leds[RED_LED]);
211 
212 	atomic_set(&shark->brightness[RED_LED], value);
213 	set_bit(RED_LED, &shark->brightness_new);
214 	schedule_work(&shark->led_work);
215 }
216 
217 static const struct led_classdev shark_led_templates[NO_LEDS] = {
218 	[BLUE_LED] = {
219 		.name		= "%s:blue:",
220 		.brightness	= LED_OFF,
221 		.max_brightness = 127,
222 		.brightness_set = shark_led_set_blue,
223 	},
224 	[BLUE_PULSE_LED] = {
225 		.name		= "%s:blue-pulse:",
226 		.brightness	= LED_OFF,
227 		.max_brightness = 255,
228 		.brightness_set = shark_led_set_blue_pulse,
229 	},
230 	[RED_LED] = {
231 		.name		= "%s:red:",
232 		.brightness	= LED_OFF,
233 		.max_brightness = 1,
234 		.brightness_set = shark_led_set_red,
235 	},
236 };
237 
238 static int shark_register_leds(struct shark_device *shark, struct device *dev)
239 {
240 	int i, retval;
241 
242 	atomic_set(&shark->brightness[BLUE_LED], 127);
243 	INIT_WORK(&shark->led_work, shark_led_work);
244 	for (i = 0; i < NO_LEDS; i++) {
245 		shark->leds[i] = shark_led_templates[i];
246 		snprintf(shark->led_names[i], sizeof(shark->led_names[0]),
247 			 shark->leds[i].name, shark->v4l2_dev.name);
248 		shark->leds[i].name = shark->led_names[i];
249 		retval = led_classdev_register(dev, &shark->leds[i]);
250 		if (retval) {
251 			v4l2_err(&shark->v4l2_dev,
252 				 "couldn't register led: %s\n",
253 				 shark->led_names[i]);
254 			return retval;
255 		}
256 	}
257 	return 0;
258 }
259 
260 static void shark_unregister_leds(struct shark_device *shark)
261 {
262 	int i;
263 
264 	for (i = 0; i < NO_LEDS; i++)
265 		led_classdev_unregister(&shark->leds[i]);
266 
267 	cancel_work_sync(&shark->led_work);
268 }
269 
270 static inline void shark_resume_leds(struct shark_device *shark)
271 {
272 	if (test_bit(BLUE_IS_PULSE, &shark->brightness_new))
273 		set_bit(BLUE_PULSE_LED, &shark->brightness_new);
274 	else
275 		set_bit(BLUE_LED, &shark->brightness_new);
276 	set_bit(RED_LED, &shark->brightness_new);
277 	schedule_work(&shark->led_work);
278 }
279 #else
280 static int shark_register_leds(struct shark_device *shark, struct device *dev)
281 {
282 	v4l2_warn(&shark->v4l2_dev,
283 		  "CONFIG_LEDS_CLASS not enabled, LED support disabled\n");
284 	return 0;
285 }
286 static inline void shark_unregister_leds(struct shark_device *shark) { }
287 static inline void shark_resume_leds(struct shark_device *shark) { }
288 #endif
289 
290 static void usb_shark_disconnect(struct usb_interface *intf)
291 {
292 	struct v4l2_device *v4l2_dev = usb_get_intfdata(intf);
293 	struct shark_device *shark = v4l2_dev_to_shark(v4l2_dev);
294 
295 	mutex_lock(&shark->tea.mutex);
296 	v4l2_device_disconnect(&shark->v4l2_dev);
297 	snd_tea575x_exit(&shark->tea);
298 	mutex_unlock(&shark->tea.mutex);
299 
300 	shark_unregister_leds(shark);
301 
302 	v4l2_device_put(&shark->v4l2_dev);
303 }
304 
305 static void usb_shark_release(struct v4l2_device *v4l2_dev)
306 {
307 	struct shark_device *shark = v4l2_dev_to_shark(v4l2_dev);
308 
309 	v4l2_device_unregister(&shark->v4l2_dev);
310 	kfree(shark->transfer_buffer);
311 	kfree(shark);
312 }
313 
314 static int usb_shark_probe(struct usb_interface *intf,
315 			   const struct usb_device_id *id)
316 {
317 	struct shark_device *shark;
318 	int retval = -ENOMEM;
319 	static const u8 ep_addresses[] = {
320 		SHARK_IN_EP | USB_DIR_IN,
321 		SHARK_OUT_EP | USB_DIR_OUT,
322 		0};
323 
324 	/* Are the expected endpoints present? */
325 	if (!usb_check_int_endpoints(intf, ep_addresses)) {
326 		dev_err(&intf->dev, "Invalid radioSHARK device\n");
327 		return -EINVAL;
328 	}
329 
330 	shark = kzalloc(sizeof(struct shark_device), GFP_KERNEL);
331 	if (!shark)
332 		return retval;
333 
334 	shark->transfer_buffer = kmalloc(TB_LEN, GFP_KERNEL);
335 	if (!shark->transfer_buffer)
336 		goto err_alloc_buffer;
337 
338 	v4l2_device_set_name(&shark->v4l2_dev, DRV_NAME, &shark_instance);
339 
340 	retval = shark_register_leds(shark, &intf->dev);
341 	if (retval)
342 		goto err_reg_leds;
343 
344 	shark->v4l2_dev.release = usb_shark_release;
345 	retval = v4l2_device_register(&intf->dev, &shark->v4l2_dev);
346 	if (retval) {
347 		v4l2_err(&shark->v4l2_dev, "couldn't register v4l2_device\n");
348 		goto err_reg_dev;
349 	}
350 
351 	shark->usbdev = interface_to_usbdev(intf);
352 	shark->tea.v4l2_dev = &shark->v4l2_dev;
353 	shark->tea.private_data = shark;
354 	shark->tea.radio_nr = -1;
355 	shark->tea.ops = &shark_tea_ops;
356 	shark->tea.cannot_mute = true;
357 	shark->tea.has_am = true;
358 	strscpy(shark->tea.card, "Griffin radioSHARK",
359 		sizeof(shark->tea.card));
360 	usb_make_path(shark->usbdev, shark->tea.bus_info,
361 		sizeof(shark->tea.bus_info));
362 
363 	retval = snd_tea575x_init(&shark->tea, THIS_MODULE);
364 	if (retval) {
365 		v4l2_err(&shark->v4l2_dev, "couldn't init tea5757\n");
366 		goto err_init_tea;
367 	}
368 
369 	return 0;
370 
371 err_init_tea:
372 	v4l2_device_unregister(&shark->v4l2_dev);
373 err_reg_dev:
374 	shark_unregister_leds(shark);
375 err_reg_leds:
376 	kfree(shark->transfer_buffer);
377 err_alloc_buffer:
378 	kfree(shark);
379 
380 	return retval;
381 }
382 
383 #ifdef CONFIG_PM
384 static int usb_shark_suspend(struct usb_interface *intf, pm_message_t message)
385 {
386 	return 0;
387 }
388 
389 static int usb_shark_resume(struct usb_interface *intf)
390 {
391 	struct v4l2_device *v4l2_dev = usb_get_intfdata(intf);
392 	struct shark_device *shark = v4l2_dev_to_shark(v4l2_dev);
393 
394 	mutex_lock(&shark->tea.mutex);
395 	snd_tea575x_set_freq(&shark->tea);
396 	mutex_unlock(&shark->tea.mutex);
397 
398 	shark_resume_leds(shark);
399 
400 	return 0;
401 }
402 #endif
403 
404 /* Specify the bcdDevice value, as the radioSHARK and radioSHARK2 share ids */
405 static const struct usb_device_id usb_shark_device_table[] = {
406 	{ .match_flags = USB_DEVICE_ID_MATCH_DEVICE_AND_VERSION |
407 			 USB_DEVICE_ID_MATCH_INT_CLASS,
408 	  .idVendor     = 0x077d,
409 	  .idProduct    = 0x627a,
410 	  .bcdDevice_lo = 0x0001,
411 	  .bcdDevice_hi = 0x0001,
412 	  .bInterfaceClass = 3,
413 	},
414 	{ }
415 };
416 MODULE_DEVICE_TABLE(usb, usb_shark_device_table);
417 
418 static struct usb_driver usb_shark_driver = {
419 	.name			= DRV_NAME,
420 	.probe			= usb_shark_probe,
421 	.disconnect		= usb_shark_disconnect,
422 	.id_table		= usb_shark_device_table,
423 #ifdef CONFIG_PM
424 	.suspend		= usb_shark_suspend,
425 	.resume			= usb_shark_resume,
426 	.reset_resume		= usb_shark_resume,
427 #endif
428 };
429 module_usb_driver(usb_shark_driver);
430