amba_pl011: Add cts-event-workaround DT property
authorPhil Elwell <phil@raspberrypi.org>
Fri, 29 Sep 2017 09:32:19 +0000 (10:32 +0100)
committerPhil Elwell <phil@raspberrypi.org>
Fri, 6 Oct 2017 08:17:07 +0000 (09:17 +0100)
commitcd361b3d9a86ddeee1faf10bcb1adae5e800d355
treecbd533e00d11f5608e5cf425c6c3a1e1098e1a6d
parentcb0f9729052e882a85816c795beec2f6e982eea2
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