linux-kernel - [PATCH v2 1/2] tty: serial: 8250

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: <2de07b0a6d51d5d3bf3e55cd03cf75adfc91ee7d.1757941345.git.daniel@makrotopia.org>
Date: Mon, 15 Sep 2025 14:06:37 +0100
From: Daniel Golle <daniel@...rotopia.org>
To: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Jiri Slaby <jirislaby@...nel.org>,
	Matthias Brugger <matthias.bgg@...il.com>,
	AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>,
	Daniel Golle <daniel@...rotopia.org>,
	Uwe Kleine-König <u.kleine-koenig@...libre.com>,
	Yu Jiaoliang <yujiaoliang@...o.com>,
	Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
	Changqi Hu <changqi.hu@...iatek.com>,
	Sam Shih <sam.shih@...iatek.com>,
	Steven Liu <steven.liu@...iatek.com>,
	John Crispin <john@...ozen.org>, linux-kernel@...r.kernel.org,
	linux-serial@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
	linux-mediatek@...ts.infradead.org
Subject: [PATCH v2 1/2] tty: serial: 8250_mtk: enable baud clock

Some MediaTek SoCs got a gated UART baud clock, which currently gets
disabled as the clk subsystem believes it would be unused. This results in
the uart freezing right after "clk: Disabling unused clocks" on those
platforms.

To fix this request the baud clock to be prepared and enabled during probe.

Fixes: e32a83c70cf9 ("serial: 8250-mtk: modify mtk uart power and clock management")
Suggested-by: Sam Shih <sam.shih@...iatek.com>
Signed-off-by: Daniel Golle <daniel@...rotopia.org>
---
v2: no changes

 drivers/tty/serial/8250/8250_mtk.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c
index b44de2ed7413..9329ed1f759d 100644
--- a/drivers/tty/serial/8250/8250_mtk.c
+++ b/drivers/tty/serial/8250/8250_mtk.c
@@ -475,13 +475,13 @@ static int mtk8250_probe_of(struct platform_device *pdev, struct uart_port *p,
 	int dmacnt;
 #endif
 
-	data->uart_clk = devm_clk_get(&pdev->dev, "baud");
+	data->uart_clk = devm_clk_get_enabled(&pdev->dev, "baud");
 	if (IS_ERR(data->uart_clk)) {
 		/*
 		 * For compatibility with older device trees try unnamed
 		 * clk when no baud clk can be found.
 		 */
-		data->uart_clk = devm_clk_get(&pdev->dev, NULL);
+		data->uart_clk = devm_clk_get_enabled(&pdev->dev, NULL);
 		if (IS_ERR(data->uart_clk)) {
 			dev_warn(&pdev->dev, "Can't get uart clock\n");
 			return PTR_ERR(data->uart_clk);
-- 
2.51.0