Hello.
> Понедельник, 2 ноября 2015, 10:24 -05:00 от Alexander Shi
> <alexander...@nanometrics.ca>:
>
> Hello all,
>
> The datasheet for MAX3107 UART (
> http://datasheets.maximintegrated.com/en/ds/MAX3107.pdf ) was updated in
> February 2015 with a notice that the RxFIFOLvl register may be inaccurate if
> read while being updated. The respective max310x.c driver in the kernel
> actively makes use of the RxFIFOLvl register, but has not been updated since
> the notice was posted. Does anyone have a workaround to this bug?
>
> The notice was phrased as follows:
> “The RxFIFOLvl register represents the current number of words in the receive
> FIFO whenever the receive UART is idle. When the receive UART actively
> receives characters, the value in this register can sometimes be inaccurate
> if this register is read at the same time that the receive UART updates the
> receive FIFO. To manage the receive FIFO even when the receive UART is
> active, do not use this register to determine receive FIFO state. Use the
> RFIFOEmptyInt bit, the RxTrgInt bit, and the RTimeOut bit instead.”
>
> Thanks,
> Alex
On my opinion this should not be a problem.
The RX interrupt will be triggered once again if we lost RX level value.
Anyway, you can add one check after reading rxfifolvl register:
if (!(ists & MAX310X_IRQ_RXEMPTY_BIT))
rxlen = 1;
Thanks.
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