On Tue, Nov 03, 2020 at 03:23:20PM +0100, gregkh@linuxfoundation.org wrote:
The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
Greg,
For linux-5.4.y, could you please do the following so that I don't need to explicitly resend these to linux-stable?
# tty: serial: fsl_lpuart: add LS1028A support git cherry-pick -xs c2f448cff22a7ed09281f02bde084b0ce3bc61ed # this is dependency # tty: serial: fsl_lpuart: LS1021A has a FIFO size of 16 words, like LS1028A git cherry-pick -xs c97f2a6fb3dfbfbbc88edc8ea62ef2b944e18849 # this is the one that failed
Both sha1sums can be found in Linus' tree.
I have tested these 2 cherry-picks on top of linux-5.4.y on my board, and it works just fine.
I was a bit concerned about backporting the LS1028A patch as a dependency for my fix, but I have consulted Documentation/process/stable-kernel-rules.rst and it says:
- New device IDs and quirks are also accepted.
That patch also satisfies the following:
- It must be obviously correct and tested. <- check - It cannot be bigger than 100 lines, with context. <- check
The patch does not apply because the fixes were discovered backwards. LS1021A and LS1028A should be compatible with one another. However when bringing up the LS1028A, Michael found the LPUART to be broken, thought the LS1021A was working, and added the FIFO size quirk as a LS1028A 'feature'.
Thanks, -Vladimir