This is a note to let you know that I've just added the patch titled

ALSA: usb-audio: Add a quirck for B&W PX headphones

to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: alsa-usb-audio-add-a-quirck-for-b-w-px-headphones.patch and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 240a8af929c7c57dcde28682725b29cf8474e8e5 Mon Sep 17 00:00:00 2001

From: Erik Veijola erik.veijola@gmail.com Date: Fri, 23 Feb 2018 14:06:52 +0200 Subject: ALSA: usb-audio: Add a quirck for B&W PX headphones

From: Erik Veijola erik.veijola@gmail.com

commit 240a8af929c7c57dcde28682725b29cf8474e8e5 upstream.

The capture interface doesn't work and the playback interface only supports 48 kHz sampling rate even though it advertises more rates.

Signed-off-by: Erik Veijola erik.veijola@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- sound/usb/quirks-table.h | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+)

--- a/sound/usb/quirks-table.h +++ b/sound/usb/quirks-table.h @@ -3277,4 +3277,51 @@ AU0828_DEVICE(0x2040, 0x7270, "Hauppauge } },

+{ + /* + * Bower's & Wilkins PX headphones only support the 48 kHz sample rate + * even though it advertises more. The capture interface doesn't work + * even on windows. + */ + USB_DEVICE(0x19b5, 0x0021), + .driver_info = (unsigned long) &(const struct snd_usb_audio_quirk) { + .ifnum = QUIRK_ANY_INTERFACE, + .type = QUIRK_COMPOSITE, + .data = (const struct snd_usb_audio_quirk[]) { + { + .ifnum = 0, + .type = QUIRK_AUDIO_STANDARD_MIXER, + }, + /* Capture */ + { + .ifnum = 1, + .type = QUIRK_IGNORE_INTERFACE, + }, + /* Playback */ + { + .ifnum = 2, + .type = QUIRK_AUDIO_FIXED_ENDPOINT, + .data = &(const struct audioformat) { + .formats = SNDRV_PCM_FMTBIT_S16_LE, + .channels = 2, + .iface = 2, + .altsetting = 1, + .altset_idx = 1, + .attributes = UAC_EP_CS_ATTR_FILL_MAX | + UAC_EP_CS_ATTR_SAMPLE_RATE, + .endpoint = 0x03, + .ep_attr = USB_ENDPOINT_XFER_ISOC, + .rates = SNDRV_PCM_RATE_48000, + .rate_min = 48000, + .rate_max = 48000, + .nr_rates = 1, + .rate_table = (unsigned int[]) { + 48000 + } + } + }, + } + } +}, + #undef USB_DEVICE_VENDOR_SPEC

Patches currently in stable-queue which might be from erik.veijola@gmail.com are

queue-4.15/alsa-usb-audio-add-a-quirck-for-b-w-px-headphones.patch