openwrt/target/linux/bcm27xx/patches-5.15/950-0059-amba_pl011-Add-cts-event-workaround-DT-property.patch
John Audia 67d998e25d
kernel: bump 5.15 to 5.15.145
Changelog: https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.145

No patches needed a rebase.

 23.05 backport:

    Rebased patch mediatek/100-dts-update-mt7622-rfb1.patch due to
    changes introduced in commit e37aa926447f ("arm64: dts: mediatek:
    mt7622: fix memory node warning check") in version v5.15.143 and we
    jumped over from v5.15.139 directly to v5.15.145.

Build system: x86_64
Build-tested: ramips/tplink_archer-a6-v3
Run-tested: ramips/tplink_archer-a6-v3

 23.05 backport:

  Stijn:
   Compile-tested: ath79/generic, ipq40xx/generic, mvebu/cortexa72, ramips/mt{7621,7620,76x8}, realtek/rtl{838x,930x}, 86/64.
   Run-tested: cortexa72 (RB5009UG+S+IN), mt7621 (EAP615-Wall v1), rtl838x (GS1900-10HP, GS1900-8HP, GS108T v3).

  Petr:
   Compile-tested: ipq807x, mvebu/cortexa9
   Run-tested: turris-omnia, prpl-haze

Tested-by: Stijn Segers <foss@volatilesystems.org> [23.05 testing]
Signed-off-by: John Audia <therealgraysky@proton.me>
Signed-off-by: Petr Štetiar <ynezz@true.cz> [23.05 refresh]
(cherry picked from commit 8de4cc77a6)
2024-01-07 12:57:30 +00:00

51 lines
1.7 KiB
Diff

From decd99704aba1800c3e62a7ed1f5cbd9c5f6526a 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
@@ -91,6 +91,12 @@ properties:
3000ms.
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
@@ -2843,6 +2843,11 @@ 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);