• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * f_uac2.c -- USB Audio Class 2.0 Function
3  *
4  * Copyright (C) 2011
5  *    Yadwinder Singh (yadi.brar01@gmail.com)
6  *    Jaswinder Singh (jaswinder.singh@linaro.org)
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 
14 #include <linux/usb/audio.h>
15 #include <linux/usb/audio-v2.h>
16 #include <linux/module.h>
17 
18 #include "u_audio.h"
19 #include "u_uac2.h"
20 
21 /*
22  * The driver implements a simple UAC_2 topology.
23  * USB-OUT -> IT_1 -> OT_3 -> ALSA_Capture
24  * ALSA_Playback -> IT_2 -> OT_4 -> USB-IN
25  * Capture and Playback sampling rates are independently
26  *  controlled by two clock sources :
27  *    CLK_5 := c_srate, and CLK_6 := p_srate
28  */
29 #define USB_OUT_IT_ID	1
30 #define IO_IN_IT_ID	2
31 #define IO_OUT_OT_ID	3
32 #define USB_IN_OT_ID	4
33 #define USB_OUT_CLK_ID	5
34 #define USB_IN_CLK_ID	6
35 
36 #define CONTROL_ABSENT	0
37 #define CONTROL_RDONLY	1
38 #define CONTROL_RDWR	3
39 
40 #define CLK_FREQ_CTRL	0
41 #define CLK_VLD_CTRL	2
42 
43 #define COPY_CTRL	0
44 #define CONN_CTRL	2
45 #define OVRLD_CTRL	4
46 #define CLSTR_CTRL	6
47 #define UNFLW_CTRL	8
48 #define OVFLW_CTRL	10
49 
50 struct f_uac2 {
51 	struct g_audio g_audio;
52 	u8 ac_intf, as_in_intf, as_out_intf;
53 	u8 ac_alt, as_in_alt, as_out_alt;	/* needed for get_alt() */
54 };
55 
func_to_uac2(struct usb_function * f)56 static inline struct f_uac2 *func_to_uac2(struct usb_function *f)
57 {
58 	return container_of(f, struct f_uac2, g_audio.func);
59 }
60 
61 static inline
g_audio_to_uac2_opts(struct g_audio * agdev)62 struct f_uac2_opts *g_audio_to_uac2_opts(struct g_audio *agdev)
63 {
64 	return container_of(agdev->func.fi, struct f_uac2_opts, func_inst);
65 }
66 
67 /* --------- USB Function Interface ------------- */
68 
69 enum {
70 	STR_ASSOC,
71 	STR_IF_CTRL,
72 	STR_CLKSRC_IN,
73 	STR_CLKSRC_OUT,
74 	STR_USB_IT,
75 	STR_IO_IT,
76 	STR_USB_OT,
77 	STR_IO_OT,
78 	STR_AS_OUT_ALT0,
79 	STR_AS_OUT_ALT1,
80 	STR_AS_IN_ALT0,
81 	STR_AS_IN_ALT1,
82 };
83 
84 static char clksrc_in[8];
85 static char clksrc_out[8];
86 
87 static struct usb_string strings_fn[] = {
88 	[STR_ASSOC].s = "Source/Sink",
89 	[STR_IF_CTRL].s = "Topology Control",
90 	[STR_CLKSRC_IN].s = clksrc_in,
91 	[STR_CLKSRC_OUT].s = clksrc_out,
92 	[STR_USB_IT].s = "USBH Out",
93 	[STR_IO_IT].s = "USBD Out",
94 	[STR_USB_OT].s = "USBH In",
95 	[STR_IO_OT].s = "USBD In",
96 	[STR_AS_OUT_ALT0].s = "Playback Inactive",
97 	[STR_AS_OUT_ALT1].s = "Playback Active",
98 	[STR_AS_IN_ALT0].s = "Capture Inactive",
99 	[STR_AS_IN_ALT1].s = "Capture Active",
100 	{ },
101 };
102 
103 static struct usb_gadget_strings str_fn = {
104 	.language = 0x0409,	/* en-us */
105 	.strings = strings_fn,
106 };
107 
108 static struct usb_gadget_strings *fn_strings[] = {
109 	&str_fn,
110 	NULL,
111 };
112 
113 static struct usb_interface_assoc_descriptor iad_desc = {
114 	.bLength = sizeof iad_desc,
115 	.bDescriptorType = USB_DT_INTERFACE_ASSOCIATION,
116 
117 	.bFirstInterface = 0,
118 	.bInterfaceCount = 3,
119 	.bFunctionClass = USB_CLASS_AUDIO,
120 	.bFunctionSubClass = UAC2_FUNCTION_SUBCLASS_UNDEFINED,
121 	.bFunctionProtocol = UAC_VERSION_2,
122 };
123 
124 /* Audio Control Interface */
125 static struct usb_interface_descriptor std_ac_if_desc = {
126 	.bLength = sizeof std_ac_if_desc,
127 	.bDescriptorType = USB_DT_INTERFACE,
128 
129 	.bAlternateSetting = 0,
130 	.bNumEndpoints = 0,
131 	.bInterfaceClass = USB_CLASS_AUDIO,
132 	.bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL,
133 	.bInterfaceProtocol = UAC_VERSION_2,
134 };
135 
136 /* Clock source for IN traffic */
137 static struct uac_clock_source_descriptor in_clk_src_desc = {
138 	.bLength = sizeof in_clk_src_desc,
139 	.bDescriptorType = USB_DT_CS_INTERFACE,
140 
141 	.bDescriptorSubtype = UAC2_CLOCK_SOURCE,
142 	.bClockID = USB_IN_CLK_ID,
143 	.bmAttributes = UAC_CLOCK_SOURCE_TYPE_INT_FIXED,
144 	.bmControls = (CONTROL_RDONLY << CLK_FREQ_CTRL),
145 	.bAssocTerminal = 0,
146 };
147 
148 /* Clock source for OUT traffic */
149 static struct uac_clock_source_descriptor out_clk_src_desc = {
150 	.bLength = sizeof out_clk_src_desc,
151 	.bDescriptorType = USB_DT_CS_INTERFACE,
152 
153 	.bDescriptorSubtype = UAC2_CLOCK_SOURCE,
154 	.bClockID = USB_OUT_CLK_ID,
155 	.bmAttributes = UAC_CLOCK_SOURCE_TYPE_INT_FIXED,
156 	.bmControls = (CONTROL_RDONLY << CLK_FREQ_CTRL),
157 	.bAssocTerminal = 0,
158 };
159 
160 /* Input Terminal for USB_OUT */
161 static struct uac2_input_terminal_descriptor usb_out_it_desc = {
162 	.bLength = sizeof usb_out_it_desc,
163 	.bDescriptorType = USB_DT_CS_INTERFACE,
164 
165 	.bDescriptorSubtype = UAC_INPUT_TERMINAL,
166 	.bTerminalID = USB_OUT_IT_ID,
167 	.wTerminalType = cpu_to_le16(UAC_TERMINAL_STREAMING),
168 	.bAssocTerminal = 0,
169 	.bCSourceID = USB_OUT_CLK_ID,
170 	.iChannelNames = 0,
171 	.bmControls = cpu_to_le16(CONTROL_RDWR << COPY_CTRL),
172 };
173 
174 /* Input Terminal for I/O-In */
175 static struct uac2_input_terminal_descriptor io_in_it_desc = {
176 	.bLength = sizeof io_in_it_desc,
177 	.bDescriptorType = USB_DT_CS_INTERFACE,
178 
179 	.bDescriptorSubtype = UAC_INPUT_TERMINAL,
180 	.bTerminalID = IO_IN_IT_ID,
181 	.wTerminalType = cpu_to_le16(UAC_INPUT_TERMINAL_UNDEFINED),
182 	.bAssocTerminal = 0,
183 	.bCSourceID = USB_IN_CLK_ID,
184 	.iChannelNames = 0,
185 	.bmControls = cpu_to_le16(CONTROL_RDWR << COPY_CTRL),
186 };
187 
188 /* Ouput Terminal for USB_IN */
189 static struct uac2_output_terminal_descriptor usb_in_ot_desc = {
190 	.bLength = sizeof usb_in_ot_desc,
191 	.bDescriptorType = USB_DT_CS_INTERFACE,
192 
193 	.bDescriptorSubtype = UAC_OUTPUT_TERMINAL,
194 	.bTerminalID = USB_IN_OT_ID,
195 	.wTerminalType = cpu_to_le16(UAC_TERMINAL_STREAMING),
196 	.bAssocTerminal = 0,
197 	.bSourceID = IO_IN_IT_ID,
198 	.bCSourceID = USB_IN_CLK_ID,
199 	.bmControls = cpu_to_le16(CONTROL_RDWR << COPY_CTRL),
200 };
201 
202 /* Ouput Terminal for I/O-Out */
203 static struct uac2_output_terminal_descriptor io_out_ot_desc = {
204 	.bLength = sizeof io_out_ot_desc,
205 	.bDescriptorType = USB_DT_CS_INTERFACE,
206 
207 	.bDescriptorSubtype = UAC_OUTPUT_TERMINAL,
208 	.bTerminalID = IO_OUT_OT_ID,
209 	.wTerminalType = cpu_to_le16(UAC_OUTPUT_TERMINAL_UNDEFINED),
210 	.bAssocTerminal = 0,
211 	.bSourceID = USB_OUT_IT_ID,
212 	.bCSourceID = USB_OUT_CLK_ID,
213 	.bmControls = cpu_to_le16(CONTROL_RDWR << COPY_CTRL),
214 };
215 
216 static struct uac2_ac_header_descriptor ac_hdr_desc = {
217 	.bLength = sizeof ac_hdr_desc,
218 	.bDescriptorType = USB_DT_CS_INTERFACE,
219 
220 	.bDescriptorSubtype = UAC_MS_HEADER,
221 	.bcdADC = cpu_to_le16(0x200),
222 	.bCategory = UAC2_FUNCTION_IO_BOX,
223 	.wTotalLength = cpu_to_le16(sizeof in_clk_src_desc
224 			+ sizeof out_clk_src_desc + sizeof usb_out_it_desc
225 			+ sizeof io_in_it_desc + sizeof usb_in_ot_desc
226 			+ sizeof io_out_ot_desc),
227 	.bmControls = 0,
228 };
229 
230 /* Audio Streaming OUT Interface - Alt0 */
231 static struct usb_interface_descriptor std_as_out_if0_desc = {
232 	.bLength = sizeof std_as_out_if0_desc,
233 	.bDescriptorType = USB_DT_INTERFACE,
234 
235 	.bAlternateSetting = 0,
236 	.bNumEndpoints = 0,
237 	.bInterfaceClass = USB_CLASS_AUDIO,
238 	.bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
239 	.bInterfaceProtocol = UAC_VERSION_2,
240 };
241 
242 /* Audio Streaming OUT Interface - Alt1 */
243 static struct usb_interface_descriptor std_as_out_if1_desc = {
244 	.bLength = sizeof std_as_out_if1_desc,
245 	.bDescriptorType = USB_DT_INTERFACE,
246 
247 	.bAlternateSetting = 1,
248 	.bNumEndpoints = 1,
249 	.bInterfaceClass = USB_CLASS_AUDIO,
250 	.bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
251 	.bInterfaceProtocol = UAC_VERSION_2,
252 };
253 
254 /* Audio Stream OUT Intface Desc */
255 static struct uac2_as_header_descriptor as_out_hdr_desc = {
256 	.bLength = sizeof as_out_hdr_desc,
257 	.bDescriptorType = USB_DT_CS_INTERFACE,
258 
259 	.bDescriptorSubtype = UAC_AS_GENERAL,
260 	.bTerminalLink = USB_OUT_IT_ID,
261 	.bmControls = 0,
262 	.bFormatType = UAC_FORMAT_TYPE_I,
263 	.bmFormats = cpu_to_le32(UAC_FORMAT_TYPE_I_PCM),
264 	.iChannelNames = 0,
265 };
266 
267 /* Audio USB_OUT Format */
268 static struct uac2_format_type_i_descriptor as_out_fmt1_desc = {
269 	.bLength = sizeof as_out_fmt1_desc,
270 	.bDescriptorType = USB_DT_CS_INTERFACE,
271 	.bDescriptorSubtype = UAC_FORMAT_TYPE,
272 	.bFormatType = UAC_FORMAT_TYPE_I,
273 };
274 
275 /* STD AS ISO OUT Endpoint */
276 static struct usb_endpoint_descriptor fs_epout_desc = {
277 	.bLength = USB_DT_ENDPOINT_SIZE,
278 	.bDescriptorType = USB_DT_ENDPOINT,
279 
280 	.bEndpointAddress = USB_DIR_OUT,
281 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
282 	.wMaxPacketSize = cpu_to_le16(1023),
283 	.bInterval = 1,
284 };
285 
286 static struct usb_endpoint_descriptor hs_epout_desc = {
287 	.bLength = USB_DT_ENDPOINT_SIZE,
288 	.bDescriptorType = USB_DT_ENDPOINT,
289 
290 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
291 	.wMaxPacketSize = cpu_to_le16(1024),
292 	.bInterval = 4,
293 };
294 
295 /* CS AS ISO OUT Endpoint */
296 static struct uac2_iso_endpoint_descriptor as_iso_out_desc = {
297 	.bLength = sizeof as_iso_out_desc,
298 	.bDescriptorType = USB_DT_CS_ENDPOINT,
299 
300 	.bDescriptorSubtype = UAC_EP_GENERAL,
301 	.bmAttributes = 0,
302 	.bmControls = 0,
303 	.bLockDelayUnits = 0,
304 	.wLockDelay = 0,
305 };
306 
307 /* Audio Streaming IN Interface - Alt0 */
308 static struct usb_interface_descriptor std_as_in_if0_desc = {
309 	.bLength = sizeof std_as_in_if0_desc,
310 	.bDescriptorType = USB_DT_INTERFACE,
311 
312 	.bAlternateSetting = 0,
313 	.bNumEndpoints = 0,
314 	.bInterfaceClass = USB_CLASS_AUDIO,
315 	.bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
316 	.bInterfaceProtocol = UAC_VERSION_2,
317 };
318 
319 /* Audio Streaming IN Interface - Alt1 */
320 static struct usb_interface_descriptor std_as_in_if1_desc = {
321 	.bLength = sizeof std_as_in_if1_desc,
322 	.bDescriptorType = USB_DT_INTERFACE,
323 
324 	.bAlternateSetting = 1,
325 	.bNumEndpoints = 1,
326 	.bInterfaceClass = USB_CLASS_AUDIO,
327 	.bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
328 	.bInterfaceProtocol = UAC_VERSION_2,
329 };
330 
331 /* Audio Stream IN Intface Desc */
332 static struct uac2_as_header_descriptor as_in_hdr_desc = {
333 	.bLength = sizeof as_in_hdr_desc,
334 	.bDescriptorType = USB_DT_CS_INTERFACE,
335 
336 	.bDescriptorSubtype = UAC_AS_GENERAL,
337 	.bTerminalLink = USB_IN_OT_ID,
338 	.bmControls = 0,
339 	.bFormatType = UAC_FORMAT_TYPE_I,
340 	.bmFormats = cpu_to_le32(UAC_FORMAT_TYPE_I_PCM),
341 	.iChannelNames = 0,
342 };
343 
344 /* Audio USB_IN Format */
345 static struct uac2_format_type_i_descriptor as_in_fmt1_desc = {
346 	.bLength = sizeof as_in_fmt1_desc,
347 	.bDescriptorType = USB_DT_CS_INTERFACE,
348 	.bDescriptorSubtype = UAC_FORMAT_TYPE,
349 	.bFormatType = UAC_FORMAT_TYPE_I,
350 };
351 
352 /* STD AS ISO IN Endpoint */
353 static struct usb_endpoint_descriptor fs_epin_desc = {
354 	.bLength = USB_DT_ENDPOINT_SIZE,
355 	.bDescriptorType = USB_DT_ENDPOINT,
356 
357 	.bEndpointAddress = USB_DIR_IN,
358 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
359 	.wMaxPacketSize = cpu_to_le16(1023),
360 	.bInterval = 1,
361 };
362 
363 static struct usb_endpoint_descriptor hs_epin_desc = {
364 	.bLength = USB_DT_ENDPOINT_SIZE,
365 	.bDescriptorType = USB_DT_ENDPOINT,
366 
367 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
368 	.wMaxPacketSize = cpu_to_le16(1024),
369 	.bInterval = 4,
370 };
371 
372 /* CS AS ISO IN Endpoint */
373 static struct uac2_iso_endpoint_descriptor as_iso_in_desc = {
374 	.bLength = sizeof as_iso_in_desc,
375 	.bDescriptorType = USB_DT_CS_ENDPOINT,
376 
377 	.bDescriptorSubtype = UAC_EP_GENERAL,
378 	.bmAttributes = 0,
379 	.bmControls = 0,
380 	.bLockDelayUnits = 0,
381 	.wLockDelay = 0,
382 };
383 
384 static struct usb_descriptor_header *fs_audio_desc[] = {
385 	(struct usb_descriptor_header *)&iad_desc,
386 	(struct usb_descriptor_header *)&std_ac_if_desc,
387 
388 	(struct usb_descriptor_header *)&ac_hdr_desc,
389 	(struct usb_descriptor_header *)&in_clk_src_desc,
390 	(struct usb_descriptor_header *)&out_clk_src_desc,
391 	(struct usb_descriptor_header *)&usb_out_it_desc,
392 	(struct usb_descriptor_header *)&io_in_it_desc,
393 	(struct usb_descriptor_header *)&usb_in_ot_desc,
394 	(struct usb_descriptor_header *)&io_out_ot_desc,
395 
396 	(struct usb_descriptor_header *)&std_as_out_if0_desc,
397 	(struct usb_descriptor_header *)&std_as_out_if1_desc,
398 
399 	(struct usb_descriptor_header *)&as_out_hdr_desc,
400 	(struct usb_descriptor_header *)&as_out_fmt1_desc,
401 	(struct usb_descriptor_header *)&fs_epout_desc,
402 	(struct usb_descriptor_header *)&as_iso_out_desc,
403 
404 	(struct usb_descriptor_header *)&std_as_in_if0_desc,
405 	(struct usb_descriptor_header *)&std_as_in_if1_desc,
406 
407 	(struct usb_descriptor_header *)&as_in_hdr_desc,
408 	(struct usb_descriptor_header *)&as_in_fmt1_desc,
409 	(struct usb_descriptor_header *)&fs_epin_desc,
410 	(struct usb_descriptor_header *)&as_iso_in_desc,
411 	NULL,
412 };
413 
414 static struct usb_descriptor_header *hs_audio_desc[] = {
415 	(struct usb_descriptor_header *)&iad_desc,
416 	(struct usb_descriptor_header *)&std_ac_if_desc,
417 
418 	(struct usb_descriptor_header *)&ac_hdr_desc,
419 	(struct usb_descriptor_header *)&in_clk_src_desc,
420 	(struct usb_descriptor_header *)&out_clk_src_desc,
421 	(struct usb_descriptor_header *)&usb_out_it_desc,
422 	(struct usb_descriptor_header *)&io_in_it_desc,
423 	(struct usb_descriptor_header *)&usb_in_ot_desc,
424 	(struct usb_descriptor_header *)&io_out_ot_desc,
425 
426 	(struct usb_descriptor_header *)&std_as_out_if0_desc,
427 	(struct usb_descriptor_header *)&std_as_out_if1_desc,
428 
429 	(struct usb_descriptor_header *)&as_out_hdr_desc,
430 	(struct usb_descriptor_header *)&as_out_fmt1_desc,
431 	(struct usb_descriptor_header *)&hs_epout_desc,
432 	(struct usb_descriptor_header *)&as_iso_out_desc,
433 
434 	(struct usb_descriptor_header *)&std_as_in_if0_desc,
435 	(struct usb_descriptor_header *)&std_as_in_if1_desc,
436 
437 	(struct usb_descriptor_header *)&as_in_hdr_desc,
438 	(struct usb_descriptor_header *)&as_in_fmt1_desc,
439 	(struct usb_descriptor_header *)&hs_epin_desc,
440 	(struct usb_descriptor_header *)&as_iso_in_desc,
441 	NULL,
442 };
443 
444 struct cntrl_cur_lay3 {
445 	__le32	dCUR;
446 };
447 
448 struct cntrl_range_lay3 {
449 	__le16	wNumSubRanges;
450 	__le32	dMIN;
451 	__le32	dMAX;
452 	__le32	dRES;
453 } __packed;
454 
set_ep_max_packet_size(const struct f_uac2_opts * uac2_opts,struct usb_endpoint_descriptor * ep_desc,unsigned int factor,bool is_playback)455 static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
456 	struct usb_endpoint_descriptor *ep_desc,
457 	unsigned int factor, bool is_playback)
458 {
459 	int chmask, srate, ssize;
460 	u16 max_packet_size;
461 
462 	if (is_playback) {
463 		chmask = uac2_opts->p_chmask;
464 		srate = uac2_opts->p_srate;
465 		ssize = uac2_opts->p_ssize;
466 	} else {
467 		chmask = uac2_opts->c_chmask;
468 		srate = uac2_opts->c_srate;
469 		ssize = uac2_opts->c_ssize;
470 	}
471 
472 	max_packet_size = num_channels(chmask) * ssize *
473 		DIV_ROUND_UP(srate, factor / (1 << (ep_desc->bInterval - 1)));
474 	ep_desc->wMaxPacketSize = cpu_to_le16(min_t(u16, max_packet_size,
475 				le16_to_cpu(ep_desc->wMaxPacketSize)));
476 }
477 
478 static int
afunc_bind(struct usb_configuration * cfg,struct usb_function * fn)479 afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
480 {
481 	struct f_uac2 *uac2 = func_to_uac2(fn);
482 	struct g_audio *agdev = func_to_g_audio(fn);
483 	struct usb_composite_dev *cdev = cfg->cdev;
484 	struct usb_gadget *gadget = cdev->gadget;
485 	struct device *dev = &gadget->dev;
486 	struct f_uac2_opts *uac2_opts;
487 	struct usb_string *us;
488 	int ret;
489 
490 	uac2_opts = container_of(fn->fi, struct f_uac2_opts, func_inst);
491 
492 	us = usb_gstrings_attach(cdev, fn_strings, ARRAY_SIZE(strings_fn));
493 	if (IS_ERR(us))
494 		return PTR_ERR(us);
495 	iad_desc.iFunction = us[STR_ASSOC].id;
496 	std_ac_if_desc.iInterface = us[STR_IF_CTRL].id;
497 	in_clk_src_desc.iClockSource = us[STR_CLKSRC_IN].id;
498 	out_clk_src_desc.iClockSource = us[STR_CLKSRC_OUT].id;
499 	usb_out_it_desc.iTerminal = us[STR_USB_IT].id;
500 	io_in_it_desc.iTerminal = us[STR_IO_IT].id;
501 	usb_in_ot_desc.iTerminal = us[STR_USB_OT].id;
502 	io_out_ot_desc.iTerminal = us[STR_IO_OT].id;
503 	std_as_out_if0_desc.iInterface = us[STR_AS_OUT_ALT0].id;
504 	std_as_out_if1_desc.iInterface = us[STR_AS_OUT_ALT1].id;
505 	std_as_in_if0_desc.iInterface = us[STR_AS_IN_ALT0].id;
506 	std_as_in_if1_desc.iInterface = us[STR_AS_IN_ALT1].id;
507 
508 
509 	/* Initialize the configurable parameters */
510 	usb_out_it_desc.bNrChannels = num_channels(uac2_opts->c_chmask);
511 	usb_out_it_desc.bmChannelConfig = cpu_to_le32(uac2_opts->c_chmask);
512 	io_in_it_desc.bNrChannels = num_channels(uac2_opts->p_chmask);
513 	io_in_it_desc.bmChannelConfig = cpu_to_le32(uac2_opts->p_chmask);
514 	as_out_hdr_desc.bNrChannels = num_channels(uac2_opts->c_chmask);
515 	as_out_hdr_desc.bmChannelConfig = cpu_to_le32(uac2_opts->c_chmask);
516 	as_in_hdr_desc.bNrChannels = num_channels(uac2_opts->p_chmask);
517 	as_in_hdr_desc.bmChannelConfig = cpu_to_le32(uac2_opts->p_chmask);
518 	as_out_fmt1_desc.bSubslotSize = uac2_opts->c_ssize;
519 	as_out_fmt1_desc.bBitResolution = uac2_opts->c_ssize * 8;
520 	as_in_fmt1_desc.bSubslotSize = uac2_opts->p_ssize;
521 	as_in_fmt1_desc.bBitResolution = uac2_opts->p_ssize * 8;
522 
523 	snprintf(clksrc_in, sizeof(clksrc_in), "%uHz", uac2_opts->p_srate);
524 	snprintf(clksrc_out, sizeof(clksrc_out), "%uHz", uac2_opts->c_srate);
525 
526 	ret = usb_interface_id(cfg, fn);
527 	if (ret < 0) {
528 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
529 		return ret;
530 	}
531 	iad_desc.bFirstInterface = ret;
532 
533 	std_ac_if_desc.bInterfaceNumber = ret;
534 	uac2->ac_intf = ret;
535 	uac2->ac_alt = 0;
536 
537 	ret = usb_interface_id(cfg, fn);
538 	if (ret < 0) {
539 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
540 		return ret;
541 	}
542 	std_as_out_if0_desc.bInterfaceNumber = ret;
543 	std_as_out_if1_desc.bInterfaceNumber = ret;
544 	uac2->as_out_intf = ret;
545 	uac2->as_out_alt = 0;
546 
547 	ret = usb_interface_id(cfg, fn);
548 	if (ret < 0) {
549 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
550 		return ret;
551 	}
552 	std_as_in_if0_desc.bInterfaceNumber = ret;
553 	std_as_in_if1_desc.bInterfaceNumber = ret;
554 	uac2->as_in_intf = ret;
555 	uac2->as_in_alt = 0;
556 
557 	/* Calculate wMaxPacketSize according to audio bandwidth */
558 	set_ep_max_packet_size(uac2_opts, &fs_epin_desc, 1000, true);
559 	set_ep_max_packet_size(uac2_opts, &fs_epout_desc, 1000, false);
560 	set_ep_max_packet_size(uac2_opts, &hs_epin_desc, 8000, true);
561 	set_ep_max_packet_size(uac2_opts, &hs_epout_desc, 8000, false);
562 
563 	agdev->out_ep = usb_ep_autoconfig(gadget, &fs_epout_desc);
564 	if (!agdev->out_ep) {
565 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
566 		return -ENODEV;
567 	}
568 
569 	agdev->in_ep = usb_ep_autoconfig(gadget, &fs_epin_desc);
570 	if (!agdev->in_ep) {
571 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
572 		return -ENODEV;
573 	}
574 
575 	agdev->in_ep_maxpsize = max_t(u16,
576 				le16_to_cpu(fs_epin_desc.wMaxPacketSize),
577 				le16_to_cpu(hs_epin_desc.wMaxPacketSize));
578 	agdev->out_ep_maxpsize = max_t(u16,
579 				le16_to_cpu(fs_epout_desc.wMaxPacketSize),
580 				le16_to_cpu(hs_epout_desc.wMaxPacketSize));
581 
582 	hs_epout_desc.bEndpointAddress = fs_epout_desc.bEndpointAddress;
583 	hs_epin_desc.bEndpointAddress = fs_epin_desc.bEndpointAddress;
584 
585 	ret = usb_assign_descriptors(fn, fs_audio_desc, hs_audio_desc, NULL,
586 				     NULL);
587 	if (ret)
588 		return ret;
589 
590 	agdev->gadget = gadget;
591 
592 	agdev->params.p_chmask = uac2_opts->p_chmask;
593 	agdev->params.p_srate = uac2_opts->p_srate;
594 	agdev->params.p_ssize = uac2_opts->p_ssize;
595 	agdev->params.c_chmask = uac2_opts->c_chmask;
596 	agdev->params.c_srate = uac2_opts->c_srate;
597 	agdev->params.c_ssize = uac2_opts->c_ssize;
598 	agdev->params.req_number = uac2_opts->req_number;
599 	ret = g_audio_setup(agdev, "UAC2 PCM", "UAC2_Gadget");
600 	if (ret)
601 		goto err_free_descs;
602 	return 0;
603 
604 err_free_descs:
605 	usb_free_all_descriptors(fn);
606 	agdev->gadget = NULL;
607 	return ret;
608 }
609 
610 static int
afunc_set_alt(struct usb_function * fn,unsigned intf,unsigned alt)611 afunc_set_alt(struct usb_function *fn, unsigned intf, unsigned alt)
612 {
613 	struct usb_composite_dev *cdev = fn->config->cdev;
614 	struct f_uac2 *uac2 = func_to_uac2(fn);
615 	struct usb_gadget *gadget = cdev->gadget;
616 	struct device *dev = &gadget->dev;
617 	int ret = 0;
618 
619 	/* No i/f has more than 2 alt settings */
620 	if (alt > 1) {
621 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
622 		return -EINVAL;
623 	}
624 
625 	if (intf == uac2->ac_intf) {
626 		/* Control I/f has only 1 AltSetting - 0 */
627 		if (alt) {
628 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
629 			return -EINVAL;
630 		}
631 		return 0;
632 	}
633 
634 	if (intf == uac2->as_out_intf) {
635 		uac2->as_out_alt = alt;
636 
637 		if (alt)
638 			ret = u_audio_start_capture(&uac2->g_audio);
639 		else
640 			u_audio_stop_capture(&uac2->g_audio);
641 	} else if (intf == uac2->as_in_intf) {
642 		uac2->as_in_alt = alt;
643 
644 		if (alt)
645 			ret = u_audio_start_playback(&uac2->g_audio);
646 		else
647 			u_audio_stop_playback(&uac2->g_audio);
648 	} else {
649 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
650 		return -EINVAL;
651 	}
652 
653 	return ret;
654 }
655 
656 static int
afunc_get_alt(struct usb_function * fn,unsigned intf)657 afunc_get_alt(struct usb_function *fn, unsigned intf)
658 {
659 	struct f_uac2 *uac2 = func_to_uac2(fn);
660 	struct g_audio *agdev = func_to_g_audio(fn);
661 
662 	if (intf == uac2->ac_intf)
663 		return uac2->ac_alt;
664 	else if (intf == uac2->as_out_intf)
665 		return uac2->as_out_alt;
666 	else if (intf == uac2->as_in_intf)
667 		return uac2->as_in_alt;
668 	else
669 		dev_err(&agdev->gadget->dev,
670 			"%s:%d Invalid Interface %d!\n",
671 			__func__, __LINE__, intf);
672 
673 	return -EINVAL;
674 }
675 
676 static void
afunc_disable(struct usb_function * fn)677 afunc_disable(struct usb_function *fn)
678 {
679 	struct f_uac2 *uac2 = func_to_uac2(fn);
680 
681 	uac2->as_in_alt = 0;
682 	uac2->as_out_alt = 0;
683 	u_audio_stop_capture(&uac2->g_audio);
684 	u_audio_stop_playback(&uac2->g_audio);
685 }
686 
687 static int
in_rq_cur(struct usb_function * fn,const struct usb_ctrlrequest * cr)688 in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
689 {
690 	struct usb_request *req = fn->config->cdev->req;
691 	struct g_audio *agdev = func_to_g_audio(fn);
692 	struct f_uac2_opts *opts;
693 	u16 w_length = le16_to_cpu(cr->wLength);
694 	u16 w_index = le16_to_cpu(cr->wIndex);
695 	u16 w_value = le16_to_cpu(cr->wValue);
696 	u8 entity_id = (w_index >> 8) & 0xff;
697 	u8 control_selector = w_value >> 8;
698 	int value = -EOPNOTSUPP;
699 	int p_srate, c_srate;
700 
701 	opts = g_audio_to_uac2_opts(agdev);
702 	p_srate = opts->p_srate;
703 	c_srate = opts->c_srate;
704 
705 	if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
706 		struct cntrl_cur_lay3 c;
707 		memset(&c, 0, sizeof(struct cntrl_cur_lay3));
708 
709 		if (entity_id == USB_IN_CLK_ID)
710 			c.dCUR = cpu_to_le32(p_srate);
711 		else if (entity_id == USB_OUT_CLK_ID)
712 			c.dCUR = cpu_to_le32(c_srate);
713 
714 		value = min_t(unsigned, w_length, sizeof c);
715 		memcpy(req->buf, &c, value);
716 	} else if (control_selector == UAC2_CS_CONTROL_CLOCK_VALID) {
717 		*(u8 *)req->buf = 1;
718 		value = min_t(unsigned, w_length, 1);
719 	} else {
720 		dev_err(&agdev->gadget->dev,
721 			"%s:%d control_selector=%d TODO!\n",
722 			__func__, __LINE__, control_selector);
723 	}
724 
725 	return value;
726 }
727 
728 static int
in_rq_range(struct usb_function * fn,const struct usb_ctrlrequest * cr)729 in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
730 {
731 	struct usb_request *req = fn->config->cdev->req;
732 	struct g_audio *agdev = func_to_g_audio(fn);
733 	struct f_uac2_opts *opts;
734 	u16 w_length = le16_to_cpu(cr->wLength);
735 	u16 w_index = le16_to_cpu(cr->wIndex);
736 	u16 w_value = le16_to_cpu(cr->wValue);
737 	u8 entity_id = (w_index >> 8) & 0xff;
738 	u8 control_selector = w_value >> 8;
739 	struct cntrl_range_lay3 r;
740 	int value = -EOPNOTSUPP;
741 	int p_srate, c_srate;
742 
743 	opts = g_audio_to_uac2_opts(agdev);
744 	p_srate = opts->p_srate;
745 	c_srate = opts->c_srate;
746 
747 	if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
748 		if (entity_id == USB_IN_CLK_ID)
749 			r.dMIN = cpu_to_le32(p_srate);
750 		else if (entity_id == USB_OUT_CLK_ID)
751 			r.dMIN = cpu_to_le32(c_srate);
752 		else
753 			return -EOPNOTSUPP;
754 
755 		r.dMAX = r.dMIN;
756 		r.dRES = 0;
757 		r.wNumSubRanges = cpu_to_le16(1);
758 
759 		value = min_t(unsigned, w_length, sizeof r);
760 		memcpy(req->buf, &r, value);
761 	} else {
762 		dev_err(&agdev->gadget->dev,
763 			"%s:%d control_selector=%d TODO!\n",
764 			__func__, __LINE__, control_selector);
765 	}
766 
767 	return value;
768 }
769 
770 static int
ac_rq_in(struct usb_function * fn,const struct usb_ctrlrequest * cr)771 ac_rq_in(struct usb_function *fn, const struct usb_ctrlrequest *cr)
772 {
773 	if (cr->bRequest == UAC2_CS_CUR)
774 		return in_rq_cur(fn, cr);
775 	else if (cr->bRequest == UAC2_CS_RANGE)
776 		return in_rq_range(fn, cr);
777 	else
778 		return -EOPNOTSUPP;
779 }
780 
781 static int
out_rq_cur(struct usb_function * fn,const struct usb_ctrlrequest * cr)782 out_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
783 {
784 	u16 w_length = le16_to_cpu(cr->wLength);
785 	u16 w_value = le16_to_cpu(cr->wValue);
786 	u8 control_selector = w_value >> 8;
787 
788 	if (control_selector == UAC2_CS_CONTROL_SAM_FREQ)
789 		return w_length;
790 
791 	return -EOPNOTSUPP;
792 }
793 
794 static int
setup_rq_inf(struct usb_function * fn,const struct usb_ctrlrequest * cr)795 setup_rq_inf(struct usb_function *fn, const struct usb_ctrlrequest *cr)
796 {
797 	struct f_uac2 *uac2 = func_to_uac2(fn);
798 	struct g_audio *agdev = func_to_g_audio(fn);
799 	u16 w_index = le16_to_cpu(cr->wIndex);
800 	u8 intf = w_index & 0xff;
801 
802 	if (intf != uac2->ac_intf) {
803 		dev_err(&agdev->gadget->dev,
804 			"%s:%d Error!\n", __func__, __LINE__);
805 		return -EOPNOTSUPP;
806 	}
807 
808 	if (cr->bRequestType & USB_DIR_IN)
809 		return ac_rq_in(fn, cr);
810 	else if (cr->bRequest == UAC2_CS_CUR)
811 		return out_rq_cur(fn, cr);
812 
813 	return -EOPNOTSUPP;
814 }
815 
816 static int
afunc_setup(struct usb_function * fn,const struct usb_ctrlrequest * cr)817 afunc_setup(struct usb_function *fn, const struct usb_ctrlrequest *cr)
818 {
819 	struct usb_composite_dev *cdev = fn->config->cdev;
820 	struct g_audio *agdev = func_to_g_audio(fn);
821 	struct usb_request *req = cdev->req;
822 	u16 w_length = le16_to_cpu(cr->wLength);
823 	int value = -EOPNOTSUPP;
824 
825 	/* Only Class specific requests are supposed to reach here */
826 	if ((cr->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS)
827 		return -EOPNOTSUPP;
828 
829 	if ((cr->bRequestType & USB_RECIP_MASK) == USB_RECIP_INTERFACE)
830 		value = setup_rq_inf(fn, cr);
831 	else
832 		dev_err(&agdev->gadget->dev, "%s:%d Error!\n",
833 				__func__, __LINE__);
834 
835 	if (value >= 0) {
836 		req->length = value;
837 		req->zero = value < w_length;
838 		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
839 		if (value < 0) {
840 			dev_err(&agdev->gadget->dev,
841 				"%s:%d Error!\n", __func__, __LINE__);
842 			req->status = 0;
843 		}
844 	}
845 
846 	return value;
847 }
848 
to_f_uac2_opts(struct config_item * item)849 static inline struct f_uac2_opts *to_f_uac2_opts(struct config_item *item)
850 {
851 	return container_of(to_config_group(item), struct f_uac2_opts,
852 			    func_inst.group);
853 }
854 
f_uac2_attr_release(struct config_item * item)855 static void f_uac2_attr_release(struct config_item *item)
856 {
857 	struct f_uac2_opts *opts = to_f_uac2_opts(item);
858 
859 	usb_put_function_instance(&opts->func_inst);
860 }
861 
862 static struct configfs_item_operations f_uac2_item_ops = {
863 	.release	= f_uac2_attr_release,
864 };
865 
866 #define UAC2_ATTRIBUTE(name)						\
867 static ssize_t f_uac2_opts_##name##_show(struct config_item *item,	\
868 					 char *page)			\
869 {									\
870 	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
871 	int result;							\
872 									\
873 	mutex_lock(&opts->lock);					\
874 	result = sprintf(page, "%u\n", opts->name);			\
875 	mutex_unlock(&opts->lock);					\
876 									\
877 	return result;							\
878 }									\
879 									\
880 static ssize_t f_uac2_opts_##name##_store(struct config_item *item,	\
881 					  const char *page, size_t len)	\
882 {									\
883 	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
884 	int ret;							\
885 	u32 num;							\
886 									\
887 	mutex_lock(&opts->lock);					\
888 	if (opts->refcnt) {						\
889 		ret = -EBUSY;						\
890 		goto end;						\
891 	}								\
892 									\
893 	ret = kstrtou32(page, 0, &num);					\
894 	if (ret)							\
895 		goto end;						\
896 									\
897 	opts->name = num;						\
898 	ret = len;							\
899 									\
900 end:									\
901 	mutex_unlock(&opts->lock);					\
902 	return ret;							\
903 }									\
904 									\
905 CONFIGFS_ATTR(f_uac2_opts_, name)
906 
907 UAC2_ATTRIBUTE(p_chmask);
908 UAC2_ATTRIBUTE(p_srate);
909 UAC2_ATTRIBUTE(p_ssize);
910 UAC2_ATTRIBUTE(c_chmask);
911 UAC2_ATTRIBUTE(c_srate);
912 UAC2_ATTRIBUTE(c_ssize);
913 UAC2_ATTRIBUTE(req_number);
914 
915 static struct configfs_attribute *f_uac2_attrs[] = {
916 	&f_uac2_opts_attr_p_chmask,
917 	&f_uac2_opts_attr_p_srate,
918 	&f_uac2_opts_attr_p_ssize,
919 	&f_uac2_opts_attr_c_chmask,
920 	&f_uac2_opts_attr_c_srate,
921 	&f_uac2_opts_attr_c_ssize,
922 	&f_uac2_opts_attr_req_number,
923 	NULL,
924 };
925 
926 static struct config_item_type f_uac2_func_type = {
927 	.ct_item_ops	= &f_uac2_item_ops,
928 	.ct_attrs	= f_uac2_attrs,
929 	.ct_owner	= THIS_MODULE,
930 };
931 
afunc_free_inst(struct usb_function_instance * f)932 static void afunc_free_inst(struct usb_function_instance *f)
933 {
934 	struct f_uac2_opts *opts;
935 
936 	opts = container_of(f, struct f_uac2_opts, func_inst);
937 	kfree(opts);
938 }
939 
afunc_alloc_inst(void)940 static struct usb_function_instance *afunc_alloc_inst(void)
941 {
942 	struct f_uac2_opts *opts;
943 
944 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
945 	if (!opts)
946 		return ERR_PTR(-ENOMEM);
947 
948 	mutex_init(&opts->lock);
949 	opts->func_inst.free_func_inst = afunc_free_inst;
950 
951 	config_group_init_type_name(&opts->func_inst.group, "",
952 				    &f_uac2_func_type);
953 
954 	opts->p_chmask = UAC2_DEF_PCHMASK;
955 	opts->p_srate = UAC2_DEF_PSRATE;
956 	opts->p_ssize = UAC2_DEF_PSSIZE;
957 	opts->c_chmask = UAC2_DEF_CCHMASK;
958 	opts->c_srate = UAC2_DEF_CSRATE;
959 	opts->c_ssize = UAC2_DEF_CSSIZE;
960 	opts->req_number = UAC2_DEF_REQ_NUM;
961 	return &opts->func_inst;
962 }
963 
afunc_free(struct usb_function * f)964 static void afunc_free(struct usb_function *f)
965 {
966 	struct g_audio *agdev;
967 	struct f_uac2_opts *opts;
968 
969 	agdev = func_to_g_audio(f);
970 	opts = container_of(f->fi, struct f_uac2_opts, func_inst);
971 	kfree(agdev);
972 	mutex_lock(&opts->lock);
973 	--opts->refcnt;
974 	mutex_unlock(&opts->lock);
975 }
976 
afunc_unbind(struct usb_configuration * c,struct usb_function * f)977 static void afunc_unbind(struct usb_configuration *c, struct usb_function *f)
978 {
979 	struct g_audio *agdev = func_to_g_audio(f);
980 
981 	g_audio_cleanup(agdev);
982 	usb_free_all_descriptors(f);
983 
984 	agdev->gadget = NULL;
985 }
986 
afunc_alloc(struct usb_function_instance * fi)987 static struct usb_function *afunc_alloc(struct usb_function_instance *fi)
988 {
989 	struct f_uac2	*uac2;
990 	struct f_uac2_opts *opts;
991 
992 	uac2 = kzalloc(sizeof(*uac2), GFP_KERNEL);
993 	if (uac2 == NULL)
994 		return ERR_PTR(-ENOMEM);
995 
996 	opts = container_of(fi, struct f_uac2_opts, func_inst);
997 	mutex_lock(&opts->lock);
998 	++opts->refcnt;
999 	mutex_unlock(&opts->lock);
1000 
1001 	uac2->g_audio.func.name = "uac2_func";
1002 	uac2->g_audio.func.bind = afunc_bind;
1003 	uac2->g_audio.func.unbind = afunc_unbind;
1004 	uac2->g_audio.func.set_alt = afunc_set_alt;
1005 	uac2->g_audio.func.get_alt = afunc_get_alt;
1006 	uac2->g_audio.func.disable = afunc_disable;
1007 	uac2->g_audio.func.setup = afunc_setup;
1008 	uac2->g_audio.func.free_func = afunc_free;
1009 
1010 	return &uac2->g_audio.func;
1011 }
1012 
1013 DECLARE_USB_FUNCTION_INIT(uac2, afunc_alloc_inst, afunc_alloc);
1014 MODULE_LICENSE("GPL");
1015 MODULE_AUTHOR("Yadwinder Singh");
1016 MODULE_AUTHOR("Jaswinder Singh");
1017