TL;DR
It is up to the driver implementation (as stated by @your-uncle-bob and @todd-wilcox). In Windows using ASIO/WDM I got these entries in the list for the UMC404HD:
...
1 UMC ASIO Driver, ASIO (4 in, 4 out)
...
16 IN 1-2 (IN 1-2), Windows WDM-KS (2 in, 0 out)
17 IN 3-4 (IN 3-4), Windows WDM-KS (2 in, 0 out)
18 OUT 1-2 (OUT 1-2), Windows WDM-KS (0 in, 2 out)
19 OUT 3-4 (OUT 3-4), Windows WDM-KS (0 in, 2 out)
But in Ubuntu, using ALSA I got just one entry:
...
7 UMC404HD 192k: USB Audio (hw:2,0), ALSA (4 in, 4 out)
...
After testing the interface in a Windows machine, I obtained what I expected:
>>> import sounddevice as sd; sd.query_devices()
* 0 M-Audio Delta ASIO, ASIO (12 in, 10 out)
1 UMC ASIO Driver, ASIO (4 in, 4 out)
2 Line 1/2 (Delta 1010LT 1/2), Windows WDM-KS (0 in, 2 out)
3 Line 1/2 (Delta 1010LT 1/2), Windows WDM-KS (2 in, 0 out)
4 Line 3/4 (Delta 1010LT 3/4), Windows WDM-KS (0 in, 2 out)
5 Line 3/4 (Delta 1010LT 3/4), Windows WDM-KS (2 in, 0 out)
6 Line 5/6 (Delta 1010LT 5/6), Windows WDM-KS (0 in, 2 out)
7 Line 5/6 (Delta 1010LT 5/6), Windows WDM-KS (2 in, 0 out)
8 Line 7/8 (Delta 1010LT 7/8), Windows WDM-KS (0 in, 2 out)
9 Line 7/8 (Delta 1010LT 7/8), Windows WDM-KS (2 in, 0 out)
10 Monitor (Delta 1010LT Monitor), Windows WDM-KS (2 in, 0 out)
11 Multichannel (Delta 1010LT Multi), Windows WDM-KS (0 in, 10 out)
12 Multichannel (Delta 1010LT Multi), Windows WDM-KS (12 in, 0 out)
13 S/PDIF 1 (Delta 1010LT SPDIF), Windows WDM-KS (0 in, 2 out)
14 S/PDIF 2 (Delta 1010LT SPDIF), Windows WDM-KS (0 in, 2 out)
15 S/PDIF (Delta 1010LT SPDIF), Windows WDM-KS (2 in, 0 out)
16 IN 1-2 (IN 1-2), Windows WDM-KS (2 in, 0 out)
17 IN 3-4 (IN 3-4), Windows WDM-KS (2 in, 0 out)
18 OUT 1-2 (OUT 1-2), Windows WDM-KS (0 in, 2 out)
19 OUT 3-4 (OUT 3-4), Windows WDM-KS (0 in, 2 out)
In Ubuntu I got this:
>>> import sounddevice as sd; sd.query_devices()
0 HDA Intel PCH: ALC3246 Analog (hw:0,0), ALSA (2 in, 2 out)
1 HDA Intel PCH: HDMI 0 (hw:0,3), ALSA (0 in, 8 out)
2 HDA Intel PCH: HDMI 1 (hw:0,7), ALSA (0 in, 8 out)
3 HDA Intel PCH: HDMI 2 (hw:0,8), ALSA (0 in, 8 out)
4 HDA Intel PCH: HDMI 3 (hw:0,9), ALSA (0 in, 8 out)
5 HDA Intel PCH: HDMI 4 (hw:0,10), ALSA (0 in, 8 out)
6 HDA NVidia: HDMI 0 (hw:1,3), ALSA (0 in, 8 out)
7 UMC404HD 192k: USB Audio (hw:2,0), ALSA (4 in, 4 out)
8 sysdefault, ALSA (128 in, 128 out)
9 front, ALSA (0 in, 2 out)
10 surround40, ALSA (0 in, 2 out)
11 surround51, ALSA (0 in, 2 out)
12 surround71, ALSA (0 in, 2 out)
13 hdmi, ALSA (0 in, 8 out)
14 pulse, ALSA (32 in, 32 out)
15 dmix, ALSA (0 in, 2 out)
* 16 default, ALSA (32 in, 32 out)