The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

Possible dependencies:

643792048ee8 ("serial: sifive: enable clocks for UART when probed")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 643792048ee84b199052e9c8f89253649ca78922 Mon Sep 17 00:00:00 2001 From: Olof Johansson olof@lixom.net Date: Tue, 20 Sep 2022 09:00:18 -0700 Subject: [PATCH] serial: sifive: enable clocks for UART when probed MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit

When the PWM driver was changed to disable clocks if no PWMs are enabled, it ended up also disabling the shared parent with the UART, since the UART doesn't do any clock enablement on its own.

To avoid these surprises, switch to clk_get_enabled().

Fixes: ace41d7564e655 ("pwm: sifive: Ensure the clk is enabled exactly once per running PWM") Cc: stable stable@kernel.org Cc: Uwe Kleine-König u.kleine-koenig@pengutronix.de Cc: Emil Renner Berthing emil.renner.berthing@canonical.com Cc: Palmer Dabbelt palmer@dabbelt.com Cc: Paul Walmsley paul.walmsley@sifive.com Reviewed-by: Palmer Dabbelt palmer@rivosinc.com Reviewed-by: Uwe Kleine-König u.kleine-koenig@pengutronix.de Acked-by: Palmer Dabbelt palmer@rivosinc.com Signed-off-by: Olof Johansson olof@lixom.net Link: https://lore.kernel.org/r/20220920160017.7315-1-olof@lixom.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

diff --git a/drivers/tty/serial/sifive.c b/drivers/tty/serial/sifive.c index 5c3a07546a58..4b1d4fe8458e 100644 --- a/drivers/tty/serial/sifive.c +++ b/drivers/tty/serial/sifive.c @@ -945,7 +945,7 @@ static int sifive_serial_probe(struct platform_device *pdev) return PTR_ERR(base); }

- clk = devm_clk_get(&pdev->dev, NULL); + clk = devm_clk_get_enabled(&pdev->dev, NULL); if (IS_ERR(clk)) { dev_err(&pdev->dev, "unable to find controller clock\n"); return PTR_ERR(clk);