On Wed, Oct 12, 2011 at 10:26:17PM +0200, Nikola Ciprich wrote: > Hello everybody, > > we're considering linux solution consisting of a lot of GSM gateways. > Internally they use usb2serial converter. I know that theoretical > limit of USB is ~127 devices, That's only per root-device. Your laptop probably has more than 1 root device in it, so you can have more. > but I'm not sure how many devices are usable in practice... Is > usbserial driver OK with large amount of devices? Does anybody have > experience with this? I think I capped the max at 256, and no one in the past 10 years has complained about it yet. If you need to, we can increase it. If you want to test it out, change the line: #define SERIAL_TTY_MINORS 254 /* loads of devices :) */ in the include/linux/usb/serial.h and rebuild the kernel and see if it works for you with a larger number. If so, please let us know and I'll be glad to increase it for real if you need it. Hope this helps, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
