• Ricard Wanderlof's avatar
    ALSA: USB-audio: Adjust max packet size calculation for tx_length_quirk · 759c90fe
    Ricard Wanderlof authored
    
    
    For the Zoom R16/24 (tx_length_quirk set), when calculating the maximum
    sample frequency, consideration must be made for the fact that four bytes
    of the packet contain a length descriptor and consequently must not be
    counted as part of the audio data.
    
    This is corroborated by the wMaxPacketSize for this device, which is 108
    bytes according for the USB playback endpoint descriptor. The frame size
    is 8 bytes (2 channels of 4 bytes each), and the 108 bytes thus work out
    as 13 * 8 + 4, i.e. corresponding to 13 frames plus the additional 4 byte
    length descriptor.
    
    Signed-off-by: default avatarRicard Wanderlof <ricardw@axis.com>
    Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
    759c90fe