mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-22 06:57:57 +00:00
51 lines
1.8 KiB
Diff
51 lines
1.8 KiB
Diff
|
From 2cb280484c8dde281972690cd67299005a796485 Mon Sep 17 00:00:00 2001
|
||
|
|
From: Phil Elwell <phil@raspberrypi.org>
|
||
|
|
Date: Fri, 29 Sep 2017 10:32:19 +0100
|
||
|
|
Subject: [PATCH] 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.yaml | 6 ++++++
|
||
|
|
drivers/tty/serial/amba-pl011.c | 5 +++++
|
||
|
|
2 files changed, 11 insertions(+)
|
||
|
|
|
||
|
|
--- a/Documentation/devicetree/bindings/serial/pl011.yaml
|
||
|
|
+++ b/Documentation/devicetree/bindings/serial/pl011.yaml
|
||
|
|
@@ -100,6 +100,12 @@ properties:
|
||
|
|
- $ref: /schemas/types.yaml#/definitions/uint32
|
||
|
|
- default: 3000
|
||
|
|
|
||
|
|
+ cts-event-workaround:
|
||
|
|
+ description:
|
||
|
|
+ Enables the (otherwise vendor-specific) workaround for the
|
||
|
|
+ CTS-induced TX lockup.
|
||
|
|
+ type: boolean
|
||
|
|
+
|
||
|
|
required:
|
||
|
|
- compatible
|
||
|
|
- reg
|
||
|
|
--- a/drivers/tty/serial/amba-pl011.c
|
||
|
|
+++ b/drivers/tty/serial/amba-pl011.c
|
||
|
|
@@ -2659,6 +2659,11 @@ static int pl011_probe(struct amba_devic
|
||
|
|
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);
|