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 v3:
fix up point reference and deference.
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..9d747a7 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->port) ||
+ (uart_console(&port8250->port) && 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->port) ||
+ (uart_console(&port8250->port) && 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 linux-serial" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
