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ALSA: usb-audio: parse UAC2 endpoint descriptors correctly

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UAC2 devices have their information about pitch control stored in a
different field. Parse it, and emulate the bits for a v1 device.

A new struct uac2_iso_endpoint_descriptor is added.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Daniel Mack 2010-05-26 18:11:38 +02:00 committed by Takashi Iwai
parent 8d09124271
commit 43b8e3bc4a
2 changed files with 58 additions and 13 deletions
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16
include/linux/usb/audio-v2.h
View File

@ -105,6 +105,22 @@ struct uac_as_header_descriptor_v2 {
__u8 iChannelNames;
} __attribute__((packed));
/* 4.10.1.2 Class-Specific AS Isochronous Audio Data Endpoint Descriptor */
struct uac2_iso_endpoint_descriptor {
__u8 bLength; /* in bytes: 8 */
__u8 bDescriptorType; /* USB_DT_CS_ENDPOINT */
__u8 bDescriptorSubtype; /* EP_GENERAL */
__u8 bmAttributes;
__u8 bmControls;
__u8 bLockDelayUnits;
__le16 wLockDelay;
} __attribute__((packed));
#define UAC2_CONTROL_PITCH (3 << 0)
#define UAC2_CONTROL_DATA_OVERRUN (3 << 2)
#define UAC2_CONTROL_DATA_UNDERRUN (3 << 4)
/* 6.1 Interrupt Data Message */
#define UAC2_INTERRUPT_DATA_MSG_VENDOR (1 << 0)

55
sound/usb/endpoint.c
View File

@ -149,6 +149,47 @@ int snd_usb_add_audio_endpoint(struct snd_usb_audio *chip, int stream, struct au
return 0;
}
static int parse_uac_endpoint_attributes(struct snd_usb_audio *chip,
struct usb_host_interface *alts,
int protocol, int iface_no)
{
/* parsed with a v1 header here. that's ok as we only look at the
* header first which is the same for both versions */
struct uac_iso_endpoint_descriptor *csep;
struct usb_interface_descriptor *altsd = get_iface_desc(alts);
int attributes = 0;
csep = snd_usb_find_desc(alts->endpoint[0].extra, alts->endpoint[0].extralen, NULL, USB_DT_CS_ENDPOINT);
/* Creamware Noah has this descriptor after the 2nd endpoint */
if (!csep && altsd->bNumEndpoints >= 2)
csep = snd_usb_find_desc(alts->endpoint[1].extra, alts->endpoint[1].extralen, NULL, USB_DT_CS_ENDPOINT);
if (!csep || csep->bLength < 7 ||
csep->bDescriptorSubtype != UAC_EP_GENERAL) {
snd_printk(KERN_WARNING "%d:%u:%d : no or invalid"
" class specific endpoint descriptor\n",
chip->dev->devnum, iface_no,
altsd->bAlternateSetting);
return 0;
}
if (protocol == UAC_VERSION_1) {
attributes = csep->bmAttributes;
} else {
struct uac2_iso_endpoint_descriptor *csep2 =
(struct uac2_iso_endpoint_descriptor *) csep;
attributes = csep->bmAttributes & UAC_EP_CS_ATTR_FILL_MAX;
/* emulate the endpoint attributes of a v1 device */
if (csep2->bmControls & UAC2_CONTROL_PITCH)
attributes |= UAC_EP_CS_ATTR_PITCH_CONTROL;
}
return attributes;
}
int snd_usb_parse_audio_endpoints(struct snd_usb_audio *chip, int iface_no)
{
struct usb_device *dev;
@ -158,7 +199,6 @@ int snd_usb_parse_audio_endpoints(struct snd_usb_audio *chip, int iface_no)
int i, altno, err, stream;
int format = 0, num_channels = 0;
struct audioformat *fp = NULL;
unsigned char *csep;
int num, protocol;
struct uac_format_type_i_continuous_descriptor *fmt;
@ -279,17 +319,6 @@ int snd_usb_parse_audio_endpoints(struct snd_usb_audio *chip, int iface_no)
fp->maxpacksize * 2)
continue;
csep = snd_usb_find_desc(alts->endpoint[0].extra, alts->endpoint[0].extralen, NULL, USB_DT_CS_ENDPOINT);
/* Creamware Noah has this descriptor after the 2nd endpoint */
if (!csep && altsd->bNumEndpoints >= 2)
csep = snd_usb_find_desc(alts->endpoint[1].extra, alts->endpoint[1].extralen, NULL, USB_DT_CS_ENDPOINT);
if (!csep || csep[0] < 7 || csep[2] != UAC_EP_GENERAL) {
snd_printk(KERN_WARNING "%d:%u:%d : no or invalid"
" class specific endpoint descriptor\n",
dev->devnum, iface_no, altno);
csep = NULL;
}
fp = kzalloc(sizeof(*fp), GFP_KERNEL);
if (! fp) {
snd_printk(KERN_ERR "cannot malloc\n");
@ -308,7 +337,7 @@ int snd_usb_parse_audio_endpoints(struct snd_usb_audio *chip, int iface_no)
if (snd_usb_get_speed(dev) == USB_SPEED_HIGH)
fp->maxpacksize = (((fp->maxpacksize >> 11) & 3) + 1)
* (fp->maxpacksize & 0x7ff);
fp->attributes = csep ? csep[3] : 0;
fp->attributes = parse_uac_endpoint_attributes(chip, alts, protocol, iface_no);
/* some quirks for attributes here */