sound/usb/helper.h

Source file repositories/reference/linux-study-clean/sound/usb/helper.h

File Facts

System
Linux kernel
Corpus path
sound/usb/helper.h
Extension
.h
Size
1546 bytes
Lines
47
Domain
Driver Families
Bucket
sound/usb
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef __USBAUDIO_HELPER_H
#define __USBAUDIO_HELPER_H

unsigned int snd_usb_combine_bytes(unsigned char *bytes, int size);

void *snd_usb_find_desc(void *descstart, int desclen, void *after, u8 dtype);
void *snd_usb_find_csint_desc(void *descstart, int desclen, void *after, u8 dsubtype);

int snd_usb_ctl_msg(struct usb_device *dev, unsigned int pipe,
		    __u8 request, __u8 requesttype, __u16 value, __u16 index,
		    void *data, __u16 size);

unsigned char snd_usb_parse_datainterval(struct snd_usb_audio *chip,
					 struct usb_host_interface *alts);

struct usb_host_interface *
snd_usb_get_host_interface(struct snd_usb_audio *chip, int ifnum, int altsetting);

int snd_usb_add_ctrl_interface_link(struct snd_usb_audio *chip, int ifnum,
		int ctrlif);

struct usb_host_interface *snd_usb_find_ctrl_interface(struct snd_usb_audio *chip,
								int ifnum);

/*
 * retrieve usb_interface descriptor from the host interface
 * (conditional for compatibility with the older API)
 */
#define get_iface_desc(iface)	(&(iface)->desc)
#define get_endpoint(alt,ep)	(&(alt)->endpoint[ep].desc)
#define get_ep_desc(ep)		(&(ep)->desc)
#define get_cfg_desc(cfg)	(&(cfg)->desc)

#define snd_usb_get_speed(dev) ((dev)->speed)

static inline int snd_usb_ctrl_intf(struct usb_host_interface *ctrl_intf)
{
	return get_iface_desc(ctrl_intf)->bInterfaceNumber;
}

/* in validate.c */
bool snd_usb_validate_audio_desc(void *p, int protocol);
bool snd_usb_validate_midi_desc(void *p);

#endif /* __USBAUDIO_HELPER_H */

Annotation

Implementation Notes