SMSL M8A support

[olm52]

Card specifications:

card1 USB Audio card usb6 --> 152a:85dd SMSL SMSL M8A

The output of this dac from /proc/asound is

``SMSL SMSL M8A 1.1.2 at usb-0000:00:1d.0-1.3, high speed : USB Audio Playback: Status: Stop Interface 1 Altset 1 Format: S32_LE Channels: 2 Endpoint: 1 OUT (ASYNC) Rates: 44100, 48000, 88200, 96000, 176400, 192000, 352800, 384000, 705600, 768000 Data packet interval: 125 us Interface 1 Altset 2 Format: S32_LE Channels: 2 Endpoint: 1 OUT (ASYNC) Rates: 44100, 48000, 88200, 96000, 176400, 192000, 352800, 384000, 705600, 768000 Data packet interval: 125 us Interface 1 Altset 3 Format: SPECIAL Channels: 2 Endpoint: 1 OUT (ASYNC) Rates: 44100, 48000, 88200, 96000, 176400, 192000, 352800, 384000, 705600, 768000 Data packet interval: 125 us

It should have support for DSD native up to DSD512. The patch should use Altset3?

[lintweaker]

That looks about right

[olm52]

I confirm that this is working with case USB_ID(0x152a, 0x85dd): /* SMSL M8A */ if (fp->altsetting == 3) return SNDRV_PCM_FMTBIT_DSD_U32_BE