propagate from branch 'org.openembedded.dev' (head 23aeaf6386edeac3312ef7bf65975595704646cb)

            to branch 'org.openembedded.dev.avr32' (head 60ed8ee80ed7d3ce9fd1d319931577988ff07968)

1 files changed, 71 insertions, 0 deletions

diff --git a/packages/linux/linux-2.6.18/add-flush_buffer-operation-to-uart_ops.patch b/packages/linux/linux-2.6.18/add-flush_buffer-operation-to-uart_ops.patch
new file mode 100644
index 0000000000..0c9b919900
--- /dev/null
+++ b/packages/linux/linux-2.6.18/add-flush_buffer-operation-to-uart_ops.patch
@@ -0,0 +1,71 @@
+From nobody Mon Sep 17 00:00:00 2001
+From: Håvard Skinnemoen <hskinnemoen@atmel.com>
+Date: Thu Feb 2 15:48:50 2006 +0100
+Subject: [PATCH] Add flush_buffer() operation to uart_ops
+
+Serial drivers using DMA (like the Atmel USART3 driver) tend to get
+very confused when the xmit buffer is flushed and nobody told them.
+They also tend to spew a lot of garbage since the DMA engine keeps
+running after the buffer is flushed and possibly refilled with
+unrelated data.
+
+This patch adds a new flush_buffer operation to the uart_ops struct,
+along with a call to it from uart_flush_buffer() right after the xmit
+buffer has been cleared. The driver can implement this in order to
+syncronize its internal DMA state with the xmit buffer when the buffer
+is flushed.
+
+---
+
+ Documentation/serial/driver  |   11 +++++++++++
+ drivers/serial/serial_core.c |    2 ++
+ include/linux/serial_core.h  |    1 +
+ 3 files changed, 14 insertions(+)
+
+Index: linux-2.6.16-avr32/Documentation/serial/driver
+===================================================================
+--- linux-2.6.16-avr32.orig/Documentation/serial/driver	2006-03-20 06:53:29.000000000 +0100
++++ linux-2.6.16-avr32/Documentation/serial/driver	2006-04-03 18:57:11.000000000 +0200
+@@ -186,6 +186,17 @@ hardware.
+ 	Locking: port_sem taken.
+ 	Interrupts: caller dependent.
+ 
++  flush_buffer(port)
++	Flush any write buffers, reset any DMA state and stop any
++	ongoing DMA transfers.
++
++	This will be called whenever the port->info->xmit circular
++	buffer is cleared.
++
++	Locking: port->lock taken.
++	Interrupts: locally disabled.
++	This call must not sleep
++
+   set_termios(port,termios,oldtermios)
+ 	Change the port parameters, including word length, parity, stop
+ 	bits.  Update read_status_mask and ignore_status_mask to indicate
+Index: linux-2.6.16-avr32/drivers/serial/serial_core.c
+===================================================================
+--- linux-2.6.16-avr32.orig/drivers/serial/serial_core.c	2006-03-20 06:53:29.000000000 +0100
++++ linux-2.6.16-avr32/drivers/serial/serial_core.c	2006-04-03 18:57:11.000000000 +0200
+@@ -556,6 +556,8 @@ static void uart_flush_buffer(struct tty
+ 
+ 	spin_lock_irqsave(&port->lock, flags);
+ 	uart_circ_clear(&state->info->xmit);
++	if (port->ops->flush_buffer)
++		port->ops->flush_buffer(port);
+ 	spin_unlock_irqrestore(&port->lock, flags);
+ 	tty_wakeup(tty);
+ }
+Index: linux-2.6.16-avr32/include/linux/serial_core.h
+===================================================================
+--- linux-2.6.16-avr32.orig/include/linux/serial_core.h	2006-03-20 06:53:29.000000000 +0100
++++ linux-2.6.16-avr32/include/linux/serial_core.h	2006-04-03 18:57:11.000000000 +0200
+@@ -164,6 +164,7 @@ struct uart_ops {
+ 	void		(*break_ctl)(struct uart_port *, int ctl);
+ 	int		(*startup)(struct uart_port *);
+ 	void		(*shutdown)(struct uart_port *);
++	void		(*flush_buffer)(struct uart_port *);
+ 	void		(*set_termios)(struct uart_port *, struct termios *new,
+ 				       struct termios *old);
+ 	void		(*pm)(struct uart_port *, unsigned int state,