TTY/serial driver fixes for .38

PATCH New Greg KH 1 participant 4 messages Feb 10, 2011

Subsystems (4)

TTY layer and serial drivers Char and misc drivers Hypervisor virtual console driver virtio console driver

lore

Share & tools

lore

Greg KH

author

2011-02-10 20:15 UTC #0 lore raw

PATCH 1/1 TTY/serial driver fixes for .38

Here are a few tty and serial fixes for your .38 tree.

A file got moved back that shouldn't have been moved in the tty/hvc renames, and a few other tiny bugfixes, nothing major.

Please pull from:
master.kernel.org:/pub/scm/linux/kernel/git/gregkh/tty-2.6.git/ tty-linus

All of these patches have been in the -mm and -next trees for the past week or so.

Patches will be sent to the linux-kernel mailing list, if anyone wants to see them.

thanks,

greg k-h

------------

 arch/blackfin/include/asm/bfin_serial.h    |    2 ++
 drivers/char/Makefile                      |    1 +
 drivers/{tty/hvc => char}/virtio_console.c |    2 +-
 drivers/tty/hvc/Makefile                   |    1 -
 drivers/tty/n_gsm.c                        |    1 +
 drivers/tty/serial/68360serial.c           |    1 +
 drivers/tty/serial/bfin_5xx.c              |   15 ++++++---------
 7 files changed, 12 insertions(+), 11 deletions(-)
 rename drivers/{tty/hvc => char}/virtio_console.c (99%)

---------------

Amit Shah (1):
virtio: console: Move file back to drivers/char/

Ben Hutchings (1):

      68360serial: Plumb in rs_360_get_icount()

Ken Mills (1):
n_gsm: copy mtu over when configuring via ioctl interface

Sonic Zhang (1):
serial: bfin_5xx: split uart RX lock from uart port lock to avoid deadlock

Greg Kroah-Hartman

author

2011-02-10 20:17 UTC #1 lore raw

PATCH 1/4 virtio: console: Move file back to drivers/char/

From: Amit Shah <[email protected]>

Commit 728674a7e466628df2aeec6d11a2ae1ef968fb67 moved virtio_console.c to drivers/tty/hvc/ under the perception of this being an hvc driver. It was such once, but these days it has generic communication capabilities as well, so move it to drivers/char/.

In the future, the hvc part from this file can be split off and moved under drivers/tty/hvc/.

Signed-off-by Amit Shah <[email protected]>

CC Rusty Russell <[email protected]>

Acked-by Arnd Bergmann <[email protected]>

Signed-off-by Greg Kroah-Hartman <[email protected]>

---
 drivers/char/Makefile                      |    1 +
 drivers/{tty/hvc => char}/virtio_console.c |    2 +-
 drivers/tty/hvc/Makefile                   |    1 -
 3 files changed, 2 insertions(+), 2 deletions(-)
 rename drivers/{tty/hvc => char}/virtio_console.c (99%)

drivers/char/Makefile +1 -0

index 5bc765d..8238f89 100644
@@ -30,6 +30,7 @@ obj-$(CONFIG_SYNCLINK_GT)	+= synclink_gt.o
 obj-$(CONFIG_AMIGA_BUILTIN_SERIAL) += amiserial.o
 obj-$(CONFIG_SX)		+= sx.o generic_serial.o
 obj-$(CONFIG_RIO)		+= rio/ generic_serial.o
+obj-$(CONFIG_VIRTIO_CONSOLE)	+= virtio_console.o
 obj-$(CONFIG_RAW_DRIVER)	+= raw.o
 obj-$(CONFIG_SGI_SNSC)		+= snsc.o snsc_event.o
 obj-$(CONFIG_MSPEC)		+= mspec.o

drivers/char/virtio_console.c renamed from drivers/tty/hvc/virtio_console.c +1 -1

similarity index 99%
rename from drivers/tty/hvc/virtio_console.c
rename to drivers/char/virtio_console.c
index 896a2ce..5feadee 100644
@@ -31,7 +31,7 @@
 #include <linux/virtio_console.h>
 #include <linux/wait.h>
 #include <linux/workqueue.h>
-#include "hvc_console.h"
+#include "../tty/hvc/hvc_console.h"
 
 /*
  * This is a global struct for storing common data for all the devices

drivers/tty/hvc/Makefile +0 -1

index e6bed5f..d79e7e9 100644
@@ -10,4 +10,3 @@ obj-$(CONFIG_HVC_XEN)		+= hvc_xen.o
 obj-$(CONFIG_HVC_IUCV)		+= hvc_iucv.o
 obj-$(CONFIG_HVC_UDBG)		+= hvc_udbg.o
 obj-$(CONFIG_HVCS)		+= hvcs.o
-obj-$(CONFIG_VIRTIO_CONSOLE)	+= virtio_console.o

Signature · 1 line

1.7.3.2

Greg Kroah-Hartman

author

2011-02-10 20:17 UTC #2 lore raw

PATCH 2/4 n_gsm: copy mtu over when configuring via ioctl interface

In reply to Greg KH

From: Ken Mills <[email protected]>

This field is settable but did not get copied.

Signed-off-by Ken Mills <[email protected]>

Signed-off-by Alan Cox <[email protected]>

Cc [email protected]

Signed-off-by Greg Kroah-Hartman <[email protected]>

---
 drivers/tty/n_gsm.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

drivers/tty/n_gsm.c +1 -0

index 44b8412..aa2e5d3 100644
@@ -2414,6 +2414,7 @@ static int gsmld_config(struct tty_struct *tty, struct gsm_mux *gsm,
 
 	gsm->initiator = c->initiator;
 	gsm->mru = c->mru;
+	gsm->mtu = c->mtu;
 	gsm->encoding = c->encapsulation;
 	gsm->adaption = c->adaption;
 	gsm->n2 = c->n2;

Signature · 1 line

1.7.3.2

Greg Kroah-Hartman

author

2011-02-10 20:17 UTC #3 lore raw

PATCH 4/4 serial: bfin_5xx: split uart RX lock from uart port lock to avoid deadlock

In reply to Greg KH

From: Sonic Zhang <[email protected]>

The RX lock is used to protect the RX buffer from concurrent access in DMA mode between the timer and RX interrupt routines. It is independent from the uart lock which is used to protect the TX buffer. It is possible for a uart TX transfer to be started up from the RX interrupt handler if low latency is enabled. So we need to split the locks to avoid deadlocking in this situation.

In PIO mode, the RX lock is not necessary because the handle_simple_irq and handle_level_irq functions ensure driver interrupt handlers are called once on one core.

And now that the RX path has its own lock, the TX interrupt has nothing to do with the RX path, so disabling it at the same time.

Signed-off-by Sonic Zhang <[email protected]>

Signed-off-by Mike Frysinger <[email protected]>

Signed-off-by Greg Kroah-Hartman <[email protected]>

---
 arch/blackfin/include/asm/bfin_serial.h |    2 ++
 drivers/tty/serial/bfin_5xx.c           |   15 ++++++---------
 2 files changed, 8 insertions(+), 9 deletions(-)

arch/blackfin/include/asm/bfin_serial.h +2 -0

index 1ff9f14..7dbc664 100644
@@ -10,6 +10,7 @@
 #define __BFIN_ASM_SERIAL_H__
 
 #include <linux/serial_core.h>
+#include <linux/spinlock.h>
 #include <mach/anomaly.h>
 #include <mach/bfin_serial.h>

@@ -41,6 +42,7 @@ struct bfin_serial_port {
 	struct circ_buf rx_dma_buf;
 	struct timer_list rx_dma_timer;
 	int rx_dma_nrows;
+	spinlock_t rx_lock;
 	unsigned int tx_dma_channel;
 	unsigned int rx_dma_channel;
 	struct work_struct tx_dma_workqueue;

drivers/tty/serial/bfin_5xx.c +6 -9

index e381b89..9b1ff2b 100644
@@ -370,10 +370,8 @@ static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
 {
 	struct bfin_serial_port *uart = dev_id;
 
-	spin_lock(&uart->port.lock);
 	while (UART_GET_LSR(uart) & DR)
 		bfin_serial_rx_chars(uart);
-	spin_unlock(&uart->port.lock);
 
 	return IRQ_HANDLED;
 }

@@ -490,9 +488,8 @@ void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
 {
 	int x_pos, pos;
 
-	dma_disable_irq(uart->tx_dma_channel);
-	dma_disable_irq(uart->rx_dma_channel);
-	spin_lock_bh(&uart->port.lock);
+	dma_disable_irq_nosync(uart->rx_dma_channel);
+	spin_lock_bh(&uart->rx_lock);
 
 	/* 2D DMA RX buffer ring is used. Because curr_y_count and
 	 * curr_x_count can't be read as an atomic operation,

@@ -523,8 +520,7 @@ void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
 		uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
 	}
 
-	spin_unlock_bh(&uart->port.lock);
-	dma_enable_irq(uart->tx_dma_channel);
+	spin_unlock_bh(&uart->rx_lock);
 	dma_enable_irq(uart->rx_dma_channel);
 
 	mod_timer(&(uart->rx_dma_timer), jiffies + DMA_RX_FLUSH_JIFFIES);

@@ -571,7 +567,7 @@ static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
 	unsigned short irqstat;
 	int x_pos, pos;
 
-	spin_lock(&uart->port.lock);
+	spin_lock(&uart->rx_lock);
 	irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
 	clear_dma_irqstat(uart->rx_dma_channel);

@@ -589,7 +585,7 @@ static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
 		uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
 	}
 
-	spin_unlock(&uart->port.lock);
+	spin_unlock(&uart->rx_lock);
 
 	return IRQ_HANDLED;
 }

@@ -1332,6 +1328,7 @@ static int bfin_serial_probe(struct platform_device *pdev)
 		}
 
 #ifdef CONFIG_SERIAL_BFIN_DMA
+		spin_lock_init(&uart->rx_lock);
 		uart->tx_done	    = 1;
 		uart->tx_count	    = 0;

Signature · 1 line

1.7.3.2