This is a note to let you know that I've just added the patch titled
USB: ti_usb_3410_5052: fix chars_in_buffer overhead
to the 3.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-ti_usb_3410_5052-fix-chars_in_buffer-overhead.patch
and it can be found in the queue-3.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From ff93b19eed0d5c124ee7168650a8e2e120ac8ea4 Mon Sep 17 00:00:00 2001
From: Johan Hovold <jhovold@xxxxxxxxx>
Date: Sun, 5 May 2013 20:32:32 +0200
Subject: USB: ti_usb_3410_5052: fix chars_in_buffer overhead
From: Johan Hovold <jhovold@xxxxxxxxx>
commit ff93b19eed0d5c124ee7168650a8e2e120ac8ea4 upstream.
Use the new generic usb-serial wait_until_sent implementation to wait
for hardware buffers to drain.
This removes the need to check the hardware buffers in chars_in_buffer
and thus removes the overhead introduced by commit 2c992cd73 ("USB:
ti_usb_3410_5052: query hardware-buffer status in chars_in_buffer")
without breaking tty_wait_until_sent (used by, for example, tcdrain,
tcsendbreak and close).
Signed-off-by: Johan Hovold <jhovold@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/serial/ti_usb_3410_5052.c | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)
--- a/drivers/usb/serial/ti_usb_3410_5052.c
+++ b/drivers/usb/serial/ti_usb_3410_5052.c
@@ -103,6 +103,7 @@ static int ti_write(struct tty_struct *t
const unsigned char *data, int count);
static int ti_write_room(struct tty_struct *tty);
static int ti_chars_in_buffer(struct tty_struct *tty);
+static bool ti_tx_empty(struct usb_serial_port *port);
static void ti_throttle(struct tty_struct *tty);
static void ti_unthrottle(struct tty_struct *tty);
static int ti_ioctl(struct tty_struct *tty,
@@ -228,6 +229,7 @@ static struct usb_serial_driver ti_1port
.write = ti_write,
.write_room = ti_write_room,
.chars_in_buffer = ti_chars_in_buffer,
+ .tx_empty = ti_tx_empty,
.throttle = ti_throttle,
.unthrottle = ti_unthrottle,
.ioctl = ti_ioctl,
@@ -258,6 +260,7 @@ static struct usb_serial_driver ti_2port
.write = ti_write,
.write_room = ti_write_room,
.chars_in_buffer = ti_chars_in_buffer,
+ .tx_empty = ti_tx_empty,
.throttle = ti_throttle,
.unthrottle = ti_unthrottle,
.ioctl = ti_ioctl,
@@ -686,8 +689,6 @@ static int ti_chars_in_buffer(struct tty
struct ti_port *tport = usb_get_serial_port_data(port);
int chars = 0;
unsigned long flags;
- int ret;
- u8 lsr;
if (tport == NULL)
return 0;
@@ -696,16 +697,22 @@ static int ti_chars_in_buffer(struct tty
chars = kfifo_len(&tport->write_fifo);
spin_unlock_irqrestore(&tport->tp_lock, flags);
- if (!chars) {
- ret = ti_get_lsr(tport, &lsr);
- if (!ret && !(lsr & TI_LSR_TX_EMPTY))
- chars = 1;
- }
-
dev_dbg(&port->dev, "%s - returns %d\n", __func__, chars);
return chars;
}
+static bool ti_tx_empty(struct usb_serial_port *port)
+{
+ struct ti_port *tport = usb_get_serial_port_data(port);
+ int ret;
+ u8 lsr;
+
+ ret = ti_get_lsr(tport, &lsr);
+ if (!ret && !(lsr & TI_LSR_TX_EMPTY))
+ return false;
+
+ return true;
+}
static void ti_throttle(struct tty_struct *tty)
{
Patches currently in stable-queue which might be from jhovold@xxxxxxxxx are
queue-3.9/usb-mos7720-fix-dma-to-stack.patch
queue-3.9/usb-ti_usb_3410_5052-fix-chars_in_buffer-overhead.patch
queue-3.9/usb-ftdi_sio-clean-up-get_modem_status.patch
queue-3.9/usb-ftdi_sio-fix-chars_in_buffer-overhead.patch
queue-3.9/usb-zte_ev-fix-broken-open.patch
queue-3.9/usb-ark3116-fix-control-message-timeout.patch
queue-3.9/usb-serial-add-wait_until_sent-operation.patch
queue-3.9/usb-io_ti-fix-chars_in_buffer-overhead.patch
queue-3.9/usb-mos7840-fix-dma-to-stack.patch
queue-3.9/usb-serial-fix-treo-kyocera-interrrupt-in-urb-context.patch
queue-3.9/usb-ti_usb_3410_5052-query-hardware-buffer-status-in-chars_in_buffer.patch
queue-3.9/usb-serial-add-generic-wait_until_sent-implementation.patch
queue-3.9/usb-mos7720-fix-hardware-flow-control.patch
queue-3.9/usb-keyspan-fix-bogus-array-index.patch
queue-3.9/usb-zte_ev-fix-control-message-timeouts.patch
queue-3.9/usb-mos7720-fix-message-timeouts.patch
queue-3.9/usb-iuu_phoenix-fix-bulk-message-timeout.patch
queue-3.9/usb-whiteheat-fix-broken-port-configuration.patch
queue-3.9/usb-ti_usb_3410_5052-remove-lsr-from-port-data.patch
queue-3.9/usb-visor-fix-initialisation-of-treo-kyocera-devices.patch
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