This patch fixes commit 2dea53bf57783f243c892e99c10c6921e956aa7e, "serial: of-serial: add PM suspend/resume support", which disables the uart clock on suspend, but also causes a hardware hang on register access if no_console_suspend command line option is used. Also, not every of_serial device is an 8250 port, so the serial8250 suspend/resume functions should only be applied to a real 8250 port. Signed-off-by: Jingchang Lu <jingchang.lu@xxxxxxxxxxxxx> --- changes in v2: add switch selection on uart type. drivers/tty/serial/of_serial.c | 42 ++++++++++++++++++++++++++++++++++++------ 1 file changed, 36 insertions(+), 6 deletions(-) diff --git a/drivers/tty/serial/of_serial.c b/drivers/tty/serial/of_serial.c index 8bc2563..b525383 100644 --- a/drivers/tty/serial/of_serial.c +++ b/drivers/tty/serial/of_serial.c @@ -245,9 +245,24 @@ static int of_serial_suspend(struct device *dev) { struct of_serial_info *info = dev_get_drvdata(dev); - serial8250_suspend_port(info->line); - if (info->clk) - clk_disable_unprepare(info->clk); + switch(info->type) { +#ifdef CONFIG_SERIAL_8250 + case PORT_8250 ... PORT_MAX_8250: + { + struct uart_8250_port port8250; + port8250 = serial8250_get_port(info->line); + + serial8250_suspend_port(info->line); + if (info->clk && + (!uart_console(port8250) || + (uart_console(port8250) && console_suspend_enabled))) + clk_disable_unprepare(info->clk); + break; + } +#endif + default: + break; + } return 0; } @@ -256,10 +271,25 @@ static int of_serial_resume(struct device *dev) { struct of_serial_info *info = dev_get_drvdata(dev); - if (info->clk) - clk_prepare_enable(info->clk); + switch(info->type) { +#ifdef CONFIG_SERIAL_8250 + case PORT_8250 ... PORT_MAX_8250: + { + struct uart_8250_port port8250; + port8250 = serial8250_get_port(info->line); + + if (info->clk && + (!uart_console(port8250) || + (uart_console(port8250) && console_suspend_enabled))) + clk_prepare_enable(info->clk); - serial8250_resume_port(info->line); + serial8250_resume_port(info->line); + break; + } +#endif + default: + break; + } return 0; } -- 1.8.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html