Re: [PATCH] Airprime driver improvements to allow full speed EvDO transfers

Alan Cox
2006-07-07T19:50:14Z

Ar Gwe, 2006-07-07 am 21:23 +0400, ysgrifennodd Sergei Organov:
> It seems that there is much worse problem here. The amount of data that
> has been inserted by the tty_insert_flip_string() could be up to
> URB_TRANSFER_BUFFER_SIZE (=4096 bytes) and may easily exceed
> TTY_THRESHOLD_THROTTLE (=128 bytes) defined in the
> char/n_tty.c.

You may throttle late but that is always true as there is an implicit
race between the hardware signals and the chip FIFO on all UART devices.
The buffering should be taking care of it, and the tty layer taking care
not to over stuff the ldisc which I thought Paul had fixed while doing
the locking wizardry

Alan