amba_pl011: Add cts-event-workaround DT property
authorPhil Elwell <phil@raspberrypi.org>
Fri, 29 Sep 2017 09:32:19 +0000 (10:32 +0100)
committerRaspbian kernel package updater <root@raspbian.org>
Sun, 8 Oct 2017 01:09:30 +0000 (01:09 +0000)
commitb60ea6c0170c149888dca480c0f6f25b2bc5b8f3
tree4b43abd903d761a5ea108093c7f0264b55ce3371
parent9c41340db6817f0281804f9a4ee3db18c1a0ddaf
amba_pl011: Add cts-event-workaround DT property

The BCM2835 PL011 implementation seems to have a bug that can lead to a
transmission lockup if CTS changes frequently. A workaround was added to
the driver with a vendor-specific flag to enable it, but this flag is
currently not set for ARM implementations.

Add a "cts-event-workaround" property to Pi DTBs and use the presence
of that property to force the flag to be enabled in the driver.

See: https://github.com/raspberrypi/linux/issues/1280

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Documentation/devicetree/bindings/serial/pl011.txt
arch/arm/boot/dts/bcm270x.dtsi
drivers/tty/serial/amba-pl011.c