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7.3.3.1. A kernel module is not loaded automatically
Udev will only load a module if it has a bus-specific alias and the bus driver properly exports the necessary aliases to sysfs. In other cases, one should arrange module loading by other means. With Linux-5.2.8, Udev is known to load properly-written drivers for INPUT, IDE, PCI, USB, SCSI, SERIO, and FireWire devices.
To determine if the device driver you require has the necessary support for Udev, run modinfo with the module name as the argument. Now try locating the device directory under /sys/bus and check whether there is a modalias file there.
If the modalias file exists in sysfs, the driver supports the device and can talk to it directly, but doesn't have the alias, it is a bug in the driver. Load the driver without the help from Udev and expect the issue to be fixed later.
If there is no modalias file in the relevant directory under /sys/bus, this means that the kernel developers have not yet added modalias support to this bus type. With Linux-5.2.8, this is the case with ISA busses. Expect this issue to be fixed in later kernel versions.
Udev is not intended to load “wrapper” drivers such as snd-pcm-oss and non-hardware drivers such as loop at all.
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