Am 23.01.2016 um 18:28 schrieb One Thousand Gnomes <gnomes@xxxxxxxxxxxxxxxxxxx>: >>> There is lots of stuff we probe and bind via user space - most things >>> these days in fact. That's much of why we have notifiers and udev. It's >>> frequently a win in flexibility, security and configurability to do stuff >>> via user daemons. We do it for example with all the volume management, >>> raid and disk encryption. >> >> Because volumes are something users really want to configure. They >> can change their hardware configuration every now and then. And >> there are removable media to be considered. > > Like USB bluetooth dongles, like systems with external SPI ports, or plug > in SPI devices, or plug in gps devices on other interfaces ? > >> In our UART cases the underlaying hardware can't be reconfigured. So >> there is no need to load this burden of config to the user. > > Plenty of uarts it can be or the BT can be muxed with other device > endpoints. Please give examples where the user can configure such a chip that is soldered on the same PCB as the SoC. > >> For BT or GPS I just want it to work the same on all devices (independently >> on how the specific chip is connected). Kernel should unify such things. >> Or it would not be a Un(iplexed)ix. > > I think you are confusing Unix and Multics. No, If I write Unix I mean Unix. The "Un" stands for "Uniplexed" which is a pun of course. But it alludes to "Unification" giving the impression of "Simplification". > > Unix is nothing to do with Linux and Unix was about creating a beautiful > system not by having a huge crap filled kernel, and no crap filled user space. > but by having only the > minimum necessary in the kernel. Unix I think you are confusing it with the goals of microkernels (e.g. Mach or Hurd). > was not about what was put in but > what was left out. Exactly. It left out complexity. E.g. everything is a file. You can use devices like files. Just open some /dev/tty and get GPS NMEA records... > > "We used to sit around in the Unix Room saying, 'What can we throw out? > Why is there this option?" - Doug McIlroy Fine. Let's throw out the idea to configure power on/off a GPS or BT device by user space daemons for hard wired chips. > > GPS is a train wreck for commonality. Most GPS requires custom binary > only user space code often obfuscated in order to meet the regulations > governing GPS technology to stop third parties using it for missile > guidance. Most GPS receivers I came across are modules which spit out NMEA records with serial 9600 bit/s. Either through RS232 or Bluetooth SPP. There may be others, but I don't want to have all problems of the world solved at once. -- hns -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
