Re: [PATCH] serial: do not call ->pm() on initialization for console port

[Atsushi Nemoto]

On Thu, 18 Oct 2007 17:18:27 +0100, Russell King <[EMAIL PROTECTED]> wrote:
> > Attached patch fixes this problem.  Is this a right way?
> > If not, I will fix the serial_txx9 driver to skip the initialization in
> > ->pm() if oldstate was -1.
> 
> I'll have to investigate further to refresh myself with what's going
> on here, but your patch looks wrong.

Thanks.  JFYI, here is some patches I tried before changing
serial_core.  Both fixes the serial console problem.

Patch 1:

diff --git a/drivers/serial/serial_txx9.c b/drivers/serial/serial_txx9.c
index 6846a6c..7ad2192 100644
--- a/drivers/serial/serial_txx9.c
+++ b/drivers/serial/serial_txx9.c
@@ -657,7 +657,15 @@ static void
 serial_txx9_pm(struct uart_port *port, unsigned int state,
              unsigned int oldstate)
 {
-       if (state == 0)
+       /*
+        * If oldstate was -1 this is called from
+        * uart_configure_port().  In this case do not initialize the
+        * port now, because the port was already initialized (for
+        * non-console port) or should not be initialized here (for
+        * console port).  If we initialized the port here we lose
+        * serial console settings.
+        */
+       if (state == 0 && oldstate != -1)
                serial_txx9_initialize(port);
 }


Patch 2:

diff --git a/drivers/serial/serial_txx9.c b/drivers/serial/serial_txx9.c
index 6846a6c..167c3a7 100644
--- a/drivers/serial/serial_txx9.c
+++ b/drivers/serial/serial_txx9.c
@@ -657,6 +657,15 @@ static void
 serial_txx9_pm(struct uart_port *port, unsigned int state,
              unsigned int oldstate)
 {
+       /*
+        * If oldstate was -1 this is called from
+        * uart_configure_port().  If we initialized the port here we
+        * lose serial console settings.
+        */
+#ifdef CONFIG_SERIAL_TXX9_CONSOLE
+       if (port->line == port->cons->index && oldstate == -1)
+               return;
+#endif
        if (state == 0)
                serial_txx9_initialize(port);
 }
@@ -742,12 +751,7 @@ static void serial_txx9_config_port(struct uart_port 
*port, int uflags)
                return;
        port->type = PORT_TXX9;
        up->port.fifosize = TXX9_SIO_TX_FIFO;
-
-#ifdef CONFIG_SERIAL_TXX9_CONSOLE
-       if (up->port.line == up->port.cons->index)
-               return;
-#endif
-       serial_txx9_initialize(port);
+       /* This port will be initialized in subsequent serial_txx9_pm() */
 }
 
 static const char *


Hope these patches help your refreshing.

---
Atsushi Nemoto
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/