From: Phil Edworthy Date: Thu, 10 May 2018 14:13:56 +0000 (+0100) Subject: serial: 8250_dw: Fix runtime PM handling X-Git-Tag: v4.18-rc1~133^2~7 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=d76c74387e1c;p=linux.git serial: 8250_dw: Fix runtime PM handling When using kgdb, you get an abort when accessing the UART registers. This is because the driver has already entered runtime PM and so turned off the bus clock needed to access the registers. To fix this, set the capability indicating Runtime PM is active while idle. Signed-off-by: Phil Edworthy Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c index 0529b5cc094b..aff04f1de3a5 100644 --- a/drivers/tty/serial/8250/8250_dw.c +++ b/drivers/tty/serial/8250/8250_dw.c @@ -576,6 +576,10 @@ static int dw8250_probe(struct platform_device *pdev) if (!data->skip_autocfg) dw8250_setup_port(p); +#ifdef CONFIG_PM + uart.capabilities |= UART_CAP_RPM; +#endif + /* If we have a valid fifosize, try hooking up DMA */ if (p->fifosize) { data->dma.rxconf.src_maxburst = p->fifosize / 4;