On 09.12.21 15:24, Maggie Maralit wrote: Hi, > My questions are: > 1. With CONFIG_USB_ACM very common and useful, why is it not enabled > by default in most platforms with USB ports like the x86_64 (normal > for laptops and Intel NUCs)? The upstream config is supposed to be minimal. Doing optimal configs is a task for distributions or people who compile their own kernel. > 2. Is there any rule or official statement from Linux Kernel > maintainers/experts, highly recommending platform developers (or > specific Ubuntu releases) to support this? (if there is, may I have a > link of the documentation mentioning such?) That is Ubuntu's job. > 3. And is there a possibility for that module to get installed in the > Linux Kernel just by the usual Linux commands (eg, "apt get > update/upgrade")? > That question depends on your distribution. I suppose every sane general purpose Linux distribution will compile and deliver cdc-acm, but I haven't checked. The configuration of your running kernel is in /proc/config.gz and is chosen by the developer's of Ubuntu if you are running their kernel. HTH Oliver
