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v5.9
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  3 */
  4
  5#include <linux/init.h>
  6#include <linux/slab.h>
  7#include <linux/usb.h>
  8
  9#include "usbaudio.h"
 10#include "helper.h"
 11#include "quirks.h"
 12
 13/*
 14 * combine bytes and get an integer value
 15 */
 16unsigned int snd_usb_combine_bytes(unsigned char *bytes, int size)
 17{
 18	switch (size) {
 19	case 1:  return *bytes;
 20	case 2:  return combine_word(bytes);
 21	case 3:  return combine_triple(bytes);
 22	case 4:  return combine_quad(bytes);
 23	default: return 0;
 24	}
 25}
 26
 27/*
 28 * parse descriptor buffer and return the pointer starting the given
 29 * descriptor type.
 30 */
 31void *snd_usb_find_desc(void *descstart, int desclen, void *after, u8 dtype)
 32{
 33	u8 *p, *end, *next;
 34
 35	p = descstart;
 36	end = p + desclen;
 37	for (; p < end;) {
 38		if (p[0] < 2)
 39			return NULL;
 40		next = p + p[0];
 41		if (next > end)
 42			return NULL;
 43		if (p[1] == dtype && (!after || (void *)p > after)) {
 44			return p;
 45		}
 46		p = next;
 47	}
 48	return NULL;
 49}
 50
 51/*
 52 * find a class-specified interface descriptor with the given subtype.
 53 */
 54void *snd_usb_find_csint_desc(void *buffer, int buflen, void *after, u8 dsubtype)
 55{
 56	unsigned char *p = after;
 57
 58	while ((p = snd_usb_find_desc(buffer, buflen, p,
 59				      USB_DT_CS_INTERFACE)) != NULL) {
 60		if (p[0] >= 3 && p[2] == dsubtype)
 61			return p;
 62	}
 63	return NULL;
 64}
 65
 66/* check the validity of pipe and EP types */
 67int snd_usb_pipe_sanity_check(struct usb_device *dev, unsigned int pipe)
 68{
 69	static const int pipetypes[4] = {
 70		PIPE_CONTROL, PIPE_ISOCHRONOUS, PIPE_BULK, PIPE_INTERRUPT
 71	};
 72	struct usb_host_endpoint *ep;
 73
 74	ep = usb_pipe_endpoint(dev, pipe);
 75	if (!ep || usb_pipetype(pipe) != pipetypes[usb_endpoint_type(&ep->desc)])
 76		return -EINVAL;
 77	return 0;
 78}
 79
 80/*
 81 * Wrapper for usb_control_msg().
 82 * Allocates a temp buffer to prevent dmaing from/to the stack.
 83 */
 84int snd_usb_ctl_msg(struct usb_device *dev, unsigned int pipe, __u8 request,
 85		    __u8 requesttype, __u16 value, __u16 index, void *data,
 86		    __u16 size)
 87{
 88	int err;
 89	void *buf = NULL;
 90	int timeout;
 91
 92	if (snd_usb_pipe_sanity_check(dev, pipe))
 93		return -EINVAL;
 94
 95	if (size > 0) {
 96		buf = kmemdup(data, size, GFP_KERNEL);
 97		if (!buf)
 98			return -ENOMEM;
 99	}
100
101	if (requesttype & USB_DIR_IN)
102		timeout = USB_CTRL_GET_TIMEOUT;
103	else
104		timeout = USB_CTRL_SET_TIMEOUT;
105
106	err = usb_control_msg(dev, pipe, request, requesttype,
107			      value, index, buf, size, timeout);
108
109	if (size > 0) {
110		memcpy(data, buf, size);
111		kfree(buf);
112	}
113
114	snd_usb_ctl_msg_quirk(dev, pipe, request, requesttype,
115			      value, index, data, size);
116
117	return err;
118}
119
120unsigned char snd_usb_parse_datainterval(struct snd_usb_audio *chip,
121					 struct usb_host_interface *alts)
122{
123	switch (snd_usb_get_speed(chip->dev)) {
124	case USB_SPEED_HIGH:
125	case USB_SPEED_WIRELESS:
126	case USB_SPEED_SUPER:
127	case USB_SPEED_SUPER_PLUS:
128		if (get_endpoint(alts, 0)->bInterval >= 1 &&
129		    get_endpoint(alts, 0)->bInterval <= 4)
130			return get_endpoint(alts, 0)->bInterval - 1;
131		break;
132	default:
133		break;
134	}
135	return 0;
136}
137
v3.15
 
  1/*
  2 *   This program is free software; you can redistribute it and/or modify
  3 *   it under the terms of the GNU General Public License as published by
  4 *   the Free Software Foundation; either version 2 of the License, or
  5 *   (at your option) any later version.
  6 *
  7 *   This program is distributed in the hope that it will be useful,
  8 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  9 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 10 *   GNU General Public License for more details.
 11 *
 12 *   You should have received a copy of the GNU General Public License
 13 *   along with this program; if not, write to the Free Software
 14 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 15 *
 16 */
 17
 18#include <linux/init.h>
 19#include <linux/slab.h>
 20#include <linux/usb.h>
 21
 22#include "usbaudio.h"
 23#include "helper.h"
 24#include "quirks.h"
 25
 26/*
 27 * combine bytes and get an integer value
 28 */
 29unsigned int snd_usb_combine_bytes(unsigned char *bytes, int size)
 30{
 31	switch (size) {
 32	case 1:  return *bytes;
 33	case 2:  return combine_word(bytes);
 34	case 3:  return combine_triple(bytes);
 35	case 4:  return combine_quad(bytes);
 36	default: return 0;
 37	}
 38}
 39
 40/*
 41 * parse descriptor buffer and return the pointer starting the given
 42 * descriptor type.
 43 */
 44void *snd_usb_find_desc(void *descstart, int desclen, void *after, u8 dtype)
 45{
 46	u8 *p, *end, *next;
 47
 48	p = descstart;
 49	end = p + desclen;
 50	for (; p < end;) {
 51		if (p[0] < 2)
 52			return NULL;
 53		next = p + p[0];
 54		if (next > end)
 55			return NULL;
 56		if (p[1] == dtype && (!after || (void *)p > after)) {
 57			return p;
 58		}
 59		p = next;
 60	}
 61	return NULL;
 62}
 63
 64/*
 65 * find a class-specified interface descriptor with the given subtype.
 66 */
 67void *snd_usb_find_csint_desc(void *buffer, int buflen, void *after, u8 dsubtype)
 68{
 69	unsigned char *p = after;
 70
 71	while ((p = snd_usb_find_desc(buffer, buflen, p,
 72				      USB_DT_CS_INTERFACE)) != NULL) {
 73		if (p[0] >= 3 && p[2] == dsubtype)
 74			return p;
 75	}
 76	return NULL;
 77}
 78
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 79/*
 80 * Wrapper for usb_control_msg().
 81 * Allocates a temp buffer to prevent dmaing from/to the stack.
 82 */
 83int snd_usb_ctl_msg(struct usb_device *dev, unsigned int pipe, __u8 request,
 84		    __u8 requesttype, __u16 value, __u16 index, void *data,
 85		    __u16 size)
 86{
 87	int err;
 88	void *buf = NULL;
 89	int timeout;
 90
 
 
 
 91	if (size > 0) {
 92		buf = kmemdup(data, size, GFP_KERNEL);
 93		if (!buf)
 94			return -ENOMEM;
 95	}
 96
 97	if (requesttype & USB_DIR_IN)
 98		timeout = USB_CTRL_GET_TIMEOUT;
 99	else
100		timeout = USB_CTRL_SET_TIMEOUT;
101
102	err = usb_control_msg(dev, pipe, request, requesttype,
103			      value, index, buf, size, timeout);
104
105	if (size > 0) {
106		memcpy(data, buf, size);
107		kfree(buf);
108	}
109
110	snd_usb_ctl_msg_quirk(dev, pipe, request, requesttype,
111			      value, index, data, size);
112
113	return err;
114}
115
116unsigned char snd_usb_parse_datainterval(struct snd_usb_audio *chip,
117					 struct usb_host_interface *alts)
118{
119	switch (snd_usb_get_speed(chip->dev)) {
120	case USB_SPEED_HIGH:
121	case USB_SPEED_WIRELESS:
122	case USB_SPEED_SUPER:
 
123		if (get_endpoint(alts, 0)->bInterval >= 1 &&
124		    get_endpoint(alts, 0)->bInterval <= 4)
125			return get_endpoint(alts, 0)->bInterval - 1;
126		break;
127	default:
128		break;
129	}
130	return 0;
131}
132