Driver for MaxLinear/Exar USB (UART) Serial Adapters
Greg,
Please see my response inline below.
Patong
Quoted 11 lines
But there is a bigger problem here:
Review
Quoted 3 lines
(quoted diff) +3
-0+ xrusb_tty_driver = alloc_tty_driver(XRUSB_TTY_MINORS); + if (!xrusb_tty_driver) + return -ENOMEM;Why are you not using the usb serial core here? You need to do that, not try to provide your own custom tty driver. That way userspace programs will "just work" with your new device, no changes needed as your major/minor number and device name would be custom only for your device, which is not acceptable.
The MaxLinear/USB serial devices support the CDC-ACM commands. Therefore, we used the cdc-acm driver instead of the usb serial driver as the starting point for developing the driver. We replaced "ACM" with "XRUSB" throughout the driver. Would it be better if we just used the same major/minor number as the CDC-ACM driver since it was based on the cdc-acm driver?
Quoted 4 lines
By doing that, your code will also be much smaller, always a good benefit as well.