[PATCH 1/2] tty: add tty_struct->dev pointer to corresponding device instance

[PATCH 1/2] tty: add tty_struct->dev pointer to corresponding device instance

[Dmitry Eremin-Solenikov]

Some device drivers (mostly tty line disciplines) would like to have way
know a struct device instance corresponding to passed tty_struct. Add
a struct device pointer to struct tty_struct and populate it during
initialize_tty_struct().

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
---
 drivers/char/tty_io.c |   17 +++++++++++++++++
 include/linux/tty.h   |    1 +
 2 files changed, 18 insertions(+), 0 deletions(-)

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index d71f0fc..2469682 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -179,6 +179,8 @@ struct tty_struct *alloc_tty_struct(void)
 
 void free_tty_struct(struct tty_struct *tty)
 {
+	if (tty->dev)
+		put_device(tty->dev);
 	kfree(tty->write_buf);
 	tty_buffer_free_all(tty);
 	kfree(tty);
@@ -2737,6 +2739,20 @@ void do_SAK(struct tty_struct *tty)
 
 EXPORT_SYMBOL(do_SAK);
 
+static int dev_match_devt(struct device *dev, void *data)
+{
+	dev_t *devt = data;
+	return dev->devt == *devt;
+}
+
+/* Must put_device() after it's unused! */
+static struct device *tty_get_device(struct tty_struct *tty)
+{
+	dev_t devt = tty_devnum(tty);
+	return class_find_device(tty_class, NULL, &devt, dev_match_devt);
+}
+
+
 /**
  *	initialize_tty_struct
  *	@tty: tty to initialize
@@ -2777,6 +2793,7 @@ void initialize_tty_struct(struct tty_struct *tty,
 	tty->ops = driver->ops;
 	tty->index = idx;
 	tty_line_name(driver, idx, tty->name);
+	tty->dev = tty_get_device(tty);
 }
 
 /**
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 931078b..d64db5a 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -254,6 +254,7 @@ struct tty_operations;
 struct tty_struct {
 	int	magic;
 	struct kref kref;
+	struct device *dev;
 	struct tty_driver *driver;
 	const struct tty_operations *ops;
 	int index;
-- 
1.7.1

[PATCH 2/2] serport: place serport serio device correctly in the device tree

[Dmitry Eremin-Solenikov]

Make serport serio device to be a child of corresponding tty device
instead of just hanging at /sys/devices/serioX.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/serio/serport.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/input/serio/serport.c b/drivers/input/serio/serport.c
index 6d34511..6e362de 100644
--- a/drivers/input/serio/serport.c
+++ b/drivers/input/serio/serport.c
@@ -165,6 +165,7 @@ static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, u
 	serio->open = serport_serio_open;
 	serio->close = serport_serio_close;
 	serio->port_data = serport;
+	serio->dev.parent = tty->dev;
 
 	serio_register_port(serport->serio);
 	printk(KERN_INFO "serio: Serial port %s\n", tty_name(tty, name));
-- 
1.7.1

Re: [PATCH 1/2] tty: add tty_struct->dev pointer to corresponding device instance

[Alan Cox]

On Mon,  9 Aug 2010 18:22:49 +0400
Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> wrote:

> Some device drivers (mostly tty line disciplines) would like to have way
> know a struct device instance corresponding to passed tty_struct. Add
> a struct device pointer to struct tty_struct and populate it during
> initialize_tty_struct().

Acked-by: Alan Cox <alan@linux.intel.com>

Re: [PATCH 2/2] serport: place serport serio device correctly in the device tree

[Dmitry Torokhov]

On Mon, Aug 09, 2010 at 06:22:50PM +0400, Dmitry Eremin-Solenikov wrote:
> Make serport serio device to be a child of corresponding tty device
> instead of just hanging at /sys/devices/serioX.
> 
> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Looks good to me.

Acked-by: Dmitry Torokhov <dtor@mail.ru>

> ---
>  drivers/input/serio/serport.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/input/serio/serport.c b/drivers/input/serio/serport.c
> index 6d34511..6e362de 100644
> --- a/drivers/input/serio/serport.c
> +++ b/drivers/input/serio/serport.c
> @@ -165,6 +165,7 @@ static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, u
>  	serio->open = serport_serio_open;
>  	serio->close = serport_serio_close;
>  	serio->port_data = serport;
> +	serio->dev.parent = tty->dev;
>  
>  	serio_register_port(serport->serio);
>  	printk(KERN_INFO "serio: Serial port %s\n", tty_name(tty, name));
> -- 
> 1.7.1
> 

-- 
Dmitry

Re: [PATCH 1/2] tty: add tty_struct->dev pointer to corresponding device instance

[Dmitry Eremin-Solenikov]

Hello,

On Mon, Aug 9, 2010 at 7:08 PM, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> On Mon,  9 Aug 2010 18:22:49 +0400
> Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> wrote:
>
>> Some device drivers (mostly tty line disciplines) would like to have way
>> know a struct device instance corresponding to passed tty_struct. Add
>> a struct device pointer to struct tty_struct and populate it during
>> initialize_tty_struct().
>
> Acked-by: Alan Cox <alan@linux.intel.com>
>

Greg, what about these two patches? Can I expect for them to be pulled
into your patch queue for 2.6.37?

-- 
With best wishes
Dmitry

Re: [PATCH 1/2] tty: add tty_struct->dev pointer to corresponding device instance

[Greg KH]

On Mon, Aug 16, 2010 at 02:57:28PM +0400, Dmitry Eremin-Solenikov wrote:
> Hello,
> 
> On Mon, Aug 9, 2010 at 7:08 PM, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> > On Mon, ?9 Aug 2010 18:22:49 +0400
> > Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> wrote:
> >
> >> Some device drivers (mostly tty line disciplines) would like to have way
> >> know a struct device instance corresponding to passed tty_struct. Add
> >> a struct device pointer to struct tty_struct and populate it during
> >> initialize_tty_struct().
> >
> > Acked-by: Alan Cox <alan@linux.intel.com>
> >
> 
> Greg, what about these two patches? Can I expect for them to be pulled
> into your patch queue for 2.6.37?

Yes, I will queue them up to my -next branch soon and will go to Linus
for .37.

thanks,

greg k-h

[PATCH 2/2] serport: place serport serio device correctly in the device tree

[Dmitry Eremin-Solenikov]

Make serport serio device to be a child of corresponding tty device
instead of just hanging at /sys/devices/serioX.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
 drivers/input/serio/serport.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/input/serio/serport.c b/drivers/input/serio/serport.c
index 6d34511..d3d832a 100644
--- a/drivers/input/serio/serport.c
+++ b/drivers/input/serio/serport.c
@@ -148,6 +148,7 @@ static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, u
 {
 	struct serport *serport = (struct serport*) tty->disc_data;
 	struct serio *serio;
+	struct device *parent;
 	char name[64];
 
 	if (test_and_set_bit(SERPORT_BUSY, &serport->flags))
@@ -157,6 +158,8 @@ static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, u
 	if (!serio)
 		return -ENOMEM;
 
+	parent = tty_get_device(tty);
+
 	strlcpy(serio->name, "Serial port", sizeof(serio->name));
 	snprintf(serio->phys, sizeof(serio->phys), "%s/serio0", tty_name(tty, name));
 	serio->id = serport->id;
@@ -165,6 +168,7 @@ static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, u
 	serio->open = serport_serio_open;
 	serio->close = serport_serio_close;
 	serio->port_data = serport;
+	serio->dev.parent = parent;
 
 	serio_register_port(serport->serio);
 	printk(KERN_INFO "serio: Serial port %s\n", tty_name(tty, name));
@@ -173,6 +177,8 @@ static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, u
 	serio_unregister_port(serport->serio);
 	serport->serio = NULL;
 
+	put_device(parent);
+
 	clear_bit(SERPORT_DEAD, &serport->flags);
 	clear_bit(SERPORT_BUSY, &serport->flags);
 
-- 
1.7.1

Re: [PATCH 2/2] serport: place serport serio device correctly in the device tree

[Greg KH]

On Fri, Aug 06, 2010 at 08:29:29PM +0400, Dmitry Eremin-Solenikov wrote:
> Make serport serio device to be a child of corresponding tty device
> instead of just hanging at /sys/devices/serioX.
> 
> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> ---
>  drivers/input/serio/serport.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/input/serio/serport.c b/drivers/input/serio/serport.c
> index 6d34511..ee0ff0c 100644
> --- a/drivers/input/serio/serport.c
> +++ b/drivers/input/serio/serport.c
> @@ -165,6 +165,7 @@ static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, u
>  	serio->open = serport_serio_open;
>  	serio->close = serport_serio_close;
>  	serio->port_data = serport;
> +	serio->dev.parent = tty_get_device(tty);

You just grabbed a reference to this device, do you ever need to free it
up?

thanks,

greg k-h

[PATCH 2/2] serport: place serport serio device correctly in the device tree

[Dmitry Eremin-Solenikov]

Make serport serio device to be a child of corresponding tty device
instead of just hanging at /sys/devices/serioX.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
 drivers/input/serio/serport.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/input/serio/serport.c b/drivers/input/serio/serport.c
index 6d34511..ee0ff0c 100644
--- a/drivers/input/serio/serport.c
+++ b/drivers/input/serio/serport.c
@@ -165,6 +165,7 @@ static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, u
 	serio->open = serport_serio_open;
 	serio->close = serport_serio_close;
 	serio->port_data = serport;
+	serio->dev.parent = tty_get_device(tty);
 
 	serio_register_port(serport->serio);
 	printk(KERN_INFO "serio: Serial port %s\n", tty_name(tty, name));
-- 
1.7.1