This is a note to let you know that I've just added the patch titled Fix serial console on SNI RM400 machines to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: fix-serial-console-on-sni-rm400-machines.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Tue Apr 10 10:31:53 CEST 2018 From: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> Date: Wed, 31 May 2017 22:21:03 +0200 Subject: Fix serial console on SNI RM400 machines From: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> [ Upstream commit e279e6d98e0cf2c2fe008b3c29042b92f0e17b1d ] sccnxp driver doesn't get the correct uart clock rate, if CONFIG_HAVE_CLOCK is disabled. Correct usage of clk API to make it work with/without it. Fixes: 90efa75f7ab0 (serial: sccnxp: Using CLK API for getting UART clock) Suggested-by: Russell King - ARM Linux <linux@xxxxxxxxxxxxxxx> Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/tty/serial/sccnxp.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) --- a/drivers/tty/serial/sccnxp.c +++ b/drivers/tty/serial/sccnxp.c @@ -884,14 +884,19 @@ static int sccnxp_probe(struct platform_ clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(clk)) { - if (PTR_ERR(clk) == -EPROBE_DEFER) { - ret = -EPROBE_DEFER; + ret = PTR_ERR(clk); + if (ret == -EPROBE_DEFER) goto err_out; - } + uartclk = 0; + } else { + clk_prepare_enable(clk); + uartclk = clk_get_rate(clk); + } + + if (!uartclk) { dev_notice(&pdev->dev, "Using default clock frequency\n"); uartclk = s->chip->freq_std; - } else - uartclk = clk_get_rate(clk); + } /* Check input frequency */ if ((uartclk < s->chip->freq_min) || (uartclk > s->chip->freq_max)) { Patches currently in stable-queue which might be from tsbogend@xxxxxxxxxxxxxxxx are queue-4.4/fix-serial-console-on-sni-rm400-machines.patch