Commit 60e93575476f (serial: samsung: enable clock before clearing pending interrupts during init) added handling of the controller clock during init. On most systems this clock is also one of the baud_clock sources and possibly used by the earlycon and thus already enabled by the bootloader. Therefore a gap exists between s3c24xx_serial_init_port disabling the clock and an attached console reenabling it, making the transition from earlycon to regular console possibly hang the system - as seen on my S3C2442 based Freerunner today. Therefore move the disabling of the clock from s3c24xx_serial_init_port below the uart port registration, effectively creating an overlap and keeping the clock running non-stop if the console wants to grab this port. Signed-off-by: Heiko Stuebner <heiko@xxxxxxxxx> --- drivers/tty/serial/samsung.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c index c1af04d..9cd706d 100644 --- a/drivers/tty/serial/samsung.c +++ b/drivers/tty/serial/samsung.c @@ -1209,7 +1209,6 @@ static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport, /* reset the fifos (and setup the uart) */ s3c24xx_serial_resetport(port, cfg); - clk_disable_unprepare(ourport->clk); return 0; } @@ -1287,6 +1286,13 @@ static int s3c24xx_serial_probe(struct platform_device *pdev) uart_add_one_port(&s3c24xx_uart_drv, &ourport->port); platform_set_drvdata(pdev, &ourport->port); + /* + * Deactivate the clock enabled in s3c24xx_serial_init_port here, + * so that a potential re-enablement through the pm-callback overlaps + * and keeps the clock enabled in this case. + */ + clk_disable_unprepare(ourport->clk); + #ifdef CONFIG_SAMSUNG_CLOCK ret = device_create_file(&pdev->dev, &dev_attr_clock_source); if (ret < 0) -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
