linux-kernel - [PATCH v1] serial: qcom_geni: Fix BT failure regression on RB2 platform

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20260107064834.1006428-1-praveen.talari@oss.qualcomm.com>
Date: Wed,  7 Jan 2026 12:18:34 +0530
From: Praveen Talari <praveen.talari@....qualcomm.com>
To: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Jiri Slaby <jirislaby@...nel.org>,
        Praveen Talari <praveen.talari@....qualcomm.com>,
        linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-serial@...r.kernel.org, bryan.odonoghue@...aro.org,
        dmitry.baryshkov@....qualcomm.com, andersson@...nel.org
Cc: psodagud@...cinc.com, djaggi@...cinc.com, quic_msavaliy@...cinc.com,
        quic_vtanuku@...cinc.com, quic_arandive@...cinc.com,
        quic_shazhuss@...cinc.com, quic_cchiluve@...cinc.com
Subject: [PATCH v1] serial: qcom_geni: Fix BT failure regression on RB2 platform

A regression in linux-next causes Bluetooth functionality to fail during
bootup on the RB2 platform, preventing proper BT initialization. However,
BT works correctly after bootup completes.

The issue occurs when runtime PM is enabled and uart_add_one_port() is
called before wakeup IRQ setup. The uart_add_one_port() call activates the
device through runtime PM, which configures GPIOs to their default state.
When wakeup IRQ registration happens afterward, it conflicts with these
GPIO settings, causing state corruption that breaks Bluetooth
functionality.

Fix this by moving runtime PM enablement and uart_add_one_port() after
wakeup IRQ registration, ensuring proper initialization order.

Reported-by: Dmitry Baryshkov <dmitry.baryshkov@....qualcomm.com>
Closes:
https://lore.kernel.org/all/20251110101043.2108414-4-praveen.talari@oss.qualcomm.com/
Fixes: 10904d725f6e ("serial: qcom-geni: Enable PM runtime for serial driver")
Signed-off-by: Praveen Talari <praveen.talari@....qualcomm.com>
---
 drivers/tty/serial/qcom_geni_serial.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 6ce6528f5c10..46a9c71630d5 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -1888,12 +1888,6 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
 	if (ret)
 		goto error;
 
-	devm_pm_runtime_enable(port->se.dev);
-
-	ret = uart_add_one_port(drv, uport);
-	if (ret)
-		goto error;
-
 	if (port->wakeup_irq > 0) {
 		device_init_wakeup(&pdev->dev, true);
 		ret = dev_pm_set_dedicated_wake_irq(&pdev->dev,
@@ -1906,6 +1900,12 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
 		}
 	}
 
+	devm_pm_runtime_enable(port->se.dev);
+
+	ret = uart_add_one_port(drv, uport);
+	if (ret)
+		goto error;
+
 	return 0;
 
 error:

base-commit: 6cd6c12031130a349a098dbeb19d8c3070d2dfbe
-- 
2.34.1