Re: [PATCH] ARM: dts: at91: Reenable UART TX pull-ups

From: Peter Rosin
Date: Tue Dec 03 2019 - 08:05:04 EST


On 2019-11-28 11:06, Ingo van Lil wrote:
> Pull-ups for SAM9 UART/USART TX lines were disabled in 5e04822f.
> However, several chips in the SAM9 family require pull-ups to prevent
> the TX lines from falling (and causing an endless break condition) when
> the transceiver is disabled.
>
> From the SAM9G20 datasheet, 32.5.1: "To prevent the TXD line from
> falling when the USART is disabled, the use of an internal pull up
> is mandatory.". This commit reenables the pull-ups for all chips having
> that sentence in their datasheets.
>
> Signed-off-by: Ingo van Lil <inguin@xxxxxx>

Sounds reasonable, and sorry for the breakage. However, perhaps a proper
fixes tag (with the prescribed length of the commit hash) should be in
there somewhere?

Fixes: 5e04822f7db5 ("ARM: dts: at91: fixes uart pinctrl, set pullup on rx, clear pullup on tx")

Also, I think the same kind of change was made to the barebox bootloader
at about the same time. Is there a fix for that queued up as well?

Cheers,
Peter