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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
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 case USB_SPEED_SUPER_PLUS:
124 if (get_endpoint(alts, 0)->bInterval >= 1 &&
125 get_endpoint(alts, 0)->bInterval <= 4)
126 return get_endpoint(alts, 0)->bInterval - 1;
127 break;
128 default:
129 break;
130 }
131 return 0;
132}
133