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>
on the device.
enum: [1, 4]
+ cts-event-workaround:
+ description:
+ Enables the (otherwise vendor-specific) workaround for the
+ CTS-induced TX lockup.
+ type: boolean
+
required:
- compatible
- reg
if (IS_ERR(uap->clk))
return PTR_ERR(uap->clk);
+ if (of_property_read_bool(dev->dev.of_node, "cts-event-workaround")) {
+ vendor->cts_event_workaround = true;
+ dev_info(&dev->dev, "cts_event_workaround enabled\n");
+ }
+
uap->reg_offset = vendor->reg_offset;
uap->vendor = vendor;
uap->fifosize = vendor->get_fifosize(dev);