This is a preliminary change for the upcoming quirk implementation.
Currently USB-audio driver tries to call usb_set_interface() whenever the format change with interface/altset modification happens. In this patch, the check is replaced with the comparison of cur_altsetting and the targeted altsetting pointer, so that the driver may skip the unnecessary function calls.
Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/usb/pcm.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c index ad39b3cca247..ae7d8a0a0a0a 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -499,7 +499,7 @@ static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt) iface = usb_ifnum_to_if(dev, fmt->iface); if (WARN_ON(!iface)) return -EINVAL; - alts = &iface->altsetting[fmt->altset_idx]; + alts = usb_altnum_to_altsetting(iface, fmt->altsetting); altsd = get_iface_desc(alts); if (WARN_ON(altsd->bAlternateSetting != fmt->altsetting)) return -EINVAL; @@ -521,9 +521,7 @@ static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt) }
/* set interface */ - if (subs->interface != fmt->iface || - subs->altset_idx != fmt->altset_idx) { - + if (iface->cur_altsetting != alts) { err = snd_usb_select_mode_quirk(subs, fmt); if (err < 0) return -EIO; @@ -537,12 +535,11 @@ static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt) } dev_dbg(&dev->dev, "setting usb interface %d:%d\n", fmt->iface, fmt->altsetting); - subs->interface = fmt->iface; - subs->altset_idx = fmt->altset_idx; - snd_usb_set_interface_quirk(dev); }
+ subs->interface = fmt->iface; + subs->altset_idx = fmt->altset_idx; subs->data_endpoint = snd_usb_add_endpoint(subs->stream->chip, alts, fmt->endpoint, subs->direction, SND_USB_ENDPOINT_TYPE_DATA);