[PATCH RFC] media: lirc: Allow lirc dev to talk to rc device

From: Srinivas KANDAGATLA
Date: Fri Jul 12 2013 - 05:03:44 EST


From: Srinivas Kandagatla <srinivas.kandagatla@xxxxxx>

The use case is simple, if any rc device has allowed protocols =
RC_TYPE_LIRC and map_name = RC_MAP_LIRC set, the driver open will be never
called. The reason for this is, all of the key maps except lirc have some
KEYS in there map, so during rc_register_device process these keys are
matched against the input drivers and open is performed, so for the case
of RC_MAP_EMPTY, a tty/vt/keyboard is matched and the driver open is
performed.

In case of lirc, there is no match and result is that there is no open
performed, however the lirc-dev will go ahead and create a /dev/lirc0
node. Now when lircd/mode2 opens this device, no data is available
because the driver was never opened.

lirc_dev seems to have no link with actual rc device w.r.t open/close.
This patch adds the missing link rc_dev pointer to lirc_driver structure
for cases like this, so that it can do the open/close of the real driver
in accordance to lircd/mode2 open/close.

Without this patch its impossible to open a rc device which has
RC_TYPE_LIRC ad RC_MAP_LIRC set.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxx>
---
drivers/media/rc/ir-lirc-codec.c | 1 +
drivers/media/rc/lirc_dev.c | 14 ++++++++++++++
include/media/lirc_dev.h | 1 +
3 files changed, 16 insertions(+), 0 deletions(-)

diff --git a/drivers/media/rc/ir-lirc-codec.c b/drivers/media/rc/ir-lirc-codec.c
index e456126..d5ad27f 100644
--- a/drivers/media/rc/ir-lirc-codec.c
+++ b/drivers/media/rc/ir-lirc-codec.c
@@ -375,6 +375,7 @@ static int ir_lirc_register(struct rc_dev *dev)
drv->code_length = sizeof(struct ir_raw_event) * 8;
drv->fops = &lirc_fops;
drv->dev = &dev->dev;
+ drv->rc_dev = dev;
drv->owner = THIS_MODULE;

drv->minor = lirc_register_driver(drv);
diff --git a/drivers/media/rc/lirc_dev.c b/drivers/media/rc/lirc_dev.c
index 8dc057b..485bf7d 100644
--- a/drivers/media/rc/lirc_dev.c
+++ b/drivers/media/rc/lirc_dev.c
@@ -35,6 +35,7 @@
#include <linux/device.h>
#include <linux/cdev.h>

+#include <media/rc-core.h>
#include <media/lirc.h>
#include <media/lirc_dev.h>

@@ -437,6 +438,7 @@ EXPORT_SYMBOL(lirc_unregister_driver);
int lirc_dev_fop_open(struct inode *inode, struct file *file)
{
struct irctl *ir;
+ struct rc_dev *rc_dev;
struct cdev *cdev;
int retval = 0;

@@ -467,6 +469,13 @@ int lirc_dev_fop_open(struct inode *inode, struct file *file)
goto error;
}

+ rc_dev = ir->d.rc_dev;
+ if (rc_dev && rc_dev->open) {
+ retval = rc_dev->open(rc_dev);
+ if (retval)
+ goto error;
+ }
+
cdev = ir->cdev;
if (try_module_get(cdev->owner)) {
ir->open++;
@@ -499,6 +508,7 @@ int lirc_dev_fop_close(struct inode *inode, struct file *file)
{
struct irctl *ir = irctls[iminor(inode)];
struct cdev *cdev;
+ struct rc_dev *rc_dev;

if (!ir) {
printk(KERN_ERR "%s: called with invalid irctl\n", __func__);
@@ -511,6 +521,10 @@ int lirc_dev_fop_close(struct inode *inode, struct file *file)

WARN_ON(mutex_lock_killable(&lirc_dev_lock));

+ rc_dev = ir->d.rc_dev;
+ if (rc_dev && rc_dev->close)
+ rc_dev->close(rc_dev);
+
ir->open--;
if (ir->attached) {
ir->d.set_use_dec(ir->d.data);
diff --git a/include/media/lirc_dev.h b/include/media/lirc_dev.h
index 168dd0b..96dccb6 100644
--- a/include/media/lirc_dev.h
+++ b/include/media/lirc_dev.h
@@ -139,6 +139,7 @@ struct lirc_driver {
struct lirc_buffer *rbuf;
int (*set_use_inc) (void *data);
void (*set_use_dec) (void *data);
+ struct rc_dev *rc_dev;
const struct file_operations *fops;
struct device *dev;
struct module *owner;
--
1.7.6.5

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