Works for me Dr. Iwai, thank you!
Much more better styled now, and less hacky.
-Geraldo
Em Ter, 6 de abr de 2021 08:48, Takashi Iwai tiwai@suse.de escreveu:
On Mon, 05 Apr 2021 15:49:20 +0200, Geraldo wrote:
Dear Linux users of Pioneer gear, please disregard v1 of this patch and
test
this instead if at all possible.
My initial assessment that we needed to let the capture EP be opened
twice was
clearly proven wrong by further testing. This is good because if we
really
needed that it would require a lot of reengineering inside ALSA.
One thing that still boggles my mind though is why we need a special
Pioneer
case inside snd_usb_parse_implicit_fb_quirk that returns 1 like a capture quirk was found.
This is a highly experimental patch on top of 5.12-rc6 that's supposed to engage implicit feedback sync on the playback for Pioneer devices.
Without
implicit feedback sync the inputs started glitching due to clock drift in about an hour in my Pioneer DJ DDJ-SR2.
Once again I'd like to thank Takashi Iwai. He's the true author of the
bulk of
this code, I just adapted it and coerced it into working.
Signed-off-by: Geraldo Nascimento geraldogabriel@gmail.com
Thanks for the patch!
It's interesting that Pioneer devices would actually work with the implicit feedback mode. It seems that the key point is to skip the capture side; IIRC, we checked applying the quirk to the playback side, but this wasn't enough or not properly working on some devices.
If that's the case, I believe a patch like below would be safer and more inconsistent: it checks the device from both playback and capture quirks with the same helper function.
Could you check whether this one works? (It's totally untested.)
thanks,
Takashi
--- a/sound/usb/implicit.c +++ b/sound/usb/implicit.c @@ -167,18 +167,27 @@ static int add_roland_implicit_fb(struct snd_usb_audio *chip, ifnum, alts); }
-/* Playback and capture EPs on Pioneer devices share the same iface/altset,
- but they don't seem working with the implicit fb mode well, hence we
- just return as if the sync were already set up.
+/* Playback and capture EPs on Pioneer devices share the same iface/altset
*/
- for the implicit feedback operation
-static int skip_pioneer_sync_ep(struct snd_usb_audio *chip,
struct audioformat *fmt,struct usb_host_interface *alts)+static bool is_pioneer_implicit_fb(struct snd_usb_audio *chip,
struct usb_host_interface *alts){ struct usb_endpoint_descriptor *epd;
if (USB_ID_VENDOR(chip->usb_id) != 0x2b73 &&USB_ID_VENDOR(chip->usb_id) != 0x08e4)return false;if (alts->desc.bInterfaceClass != USB_CLASS_VENDOR_SPEC)return false; if (alts->desc.bNumEndpoints != 2)
return 0;
return false;epd = get_endpoint(alts, 0);if (!usb_endpoint_is_isoc_out(epd) ||(epd->bmAttributes & USB_ENDPOINT_SYNCTYPE) !=USB_ENDPOINT_SYNC_ASYNC)
return false; epd = get_endpoint(alts, 1); if (!usb_endpoint_is_isoc_in(epd) ||@@ -187,8 +196,9 @@ static int skip_pioneer_sync_ep(struct snd_usb_audio *chip, USB_ENDPOINT_USAGE_DATA && (epd->bmAttributes & USB_ENDPOINT_USAGE_MASK) != USB_ENDPOINT_USAGE_IMPLICIT_FB))
return 0;return 1; /* don't handle with the implicit fb, just skip sync EP*/
return false;return true;}
static int __add_generic_implicit_fb(struct snd_usb_audio *chip, @@ -297,13 +307,11 @@ static int audioformat_implicit_fb_quirk(struct snd_usb_audio *chip, }
/* Pioneer devices with vendor spec class */
if (attr == USB_ENDPOINT_SYNC_ASYNC &&alts->desc.bInterfaceClass == USB_CLASS_VENDOR_SPEC &&(USB_ID_VENDOR(chip->usb_id) == 0x2b73 || /* Pioneer */USB_ID_VENDOR(chip->usb_id) == 0x08e4 /* Pioneer */)) {if (skip_pioneer_sync_ep(chip, fmt, alts))return 1;}
if (is_pioneer_implicit_fb(chip, alts))return add_implicit_fb_sync_ep(chip, fmt,get_endpoint(alts,1)->bEndpointAddress,
1,alts->desc.bInterfaceNumber,
alts); /* Try the generic implicit fb if available */ if (chip->generic_implicit_fb)@@ -324,6 +332,8 @@ static int audioformat_capture_quirk(struct snd_usb_audio *chip, if (p && p->type == IMPLICIT_FB_FIXED) return add_implicit_fb_sync_ep(chip, fmt, p->ep_num, 0, p->iface, NULL);
if (is_pioneer_implicit_fb(chip, alts))return 1; /* skip */ return 0;}