From: "David Härdeman" <david@hardeman.nu>
To: linux-media@vger.kernel.org
Cc: jarod@wilsonet.com, mchehab@infradead.org
Subject: [PATCH 05/10] saa7134: protect the ir user count
Date: Sat, 20 Nov 2010 00:43:02 +0100 [thread overview]
Message-ID: <20101119234302.3511.97440.stgit@localhost.localdomain> (raw)
In-Reply-To: <20101119233959.3511.91287.stgit@localhost.localdomain>
The use of the saa7134_card_ir->users seems racy, so protect the count with
a spinlock. Also use proper data types as arguments to __saa7134_ir_start()
and __saa7134_ir_stop() to remove some unnecessary casts.
Signed-off-by: David Härdeman <david@hardeman.nu>
---
drivers/media/video/saa7134/saa7134-input.c | 54 ++++++++++++++++-----------
drivers/media/video/saa7134/saa7134.h | 1 +
2 files changed, 33 insertions(+), 22 deletions(-)
diff --git a/drivers/media/video/saa7134/saa7134-input.c b/drivers/media/video/saa7134/saa7134-input.c
index 98678d9..8b80efb 100644
--- a/drivers/media/video/saa7134/saa7134-input.c
+++ b/drivers/media/video/saa7134/saa7134-input.c
@@ -402,17 +402,12 @@ static void ir_raw_decode_timer_end(unsigned long data)
ir->active = false;
}
-static int __saa7134_ir_start(void *priv)
+static void __saa7134_ir_start(struct saa7134_dev *dev)
{
- struct saa7134_dev *dev = priv;
- struct saa7134_card_ir *ir;
-
- if (!dev || !dev->remote)
- return -EINVAL;
+ struct saa7134_card_ir *ir = dev->remote;
- ir = dev->remote;
if (ir->running)
- return 0;
+ return;
ir->running = true;
ir->active = false;
@@ -427,19 +422,12 @@ static int __saa7134_ir_start(void *priv)
setup_timer(&ir->timer, ir_raw_decode_timer_end,
(unsigned long)dev);
}
-
- return 0;
}
-static void __saa7134_ir_stop(void *priv)
+static void __saa7134_ir_stop(struct saa7134_dev *dev)
{
- struct saa7134_dev *dev = priv;
- struct saa7134_card_ir *ir;
-
- if (!dev || !dev->remote)
- return;
+ struct saa7134_card_ir *ir = dev->remote;
- ir = dev->remote;
if (!ir->running)
return;
@@ -448,39 +436,60 @@ static void __saa7134_ir_stop(void *priv)
ir->active = false;
ir->running = false;
-
- return;
}
int saa7134_ir_start(struct saa7134_dev *dev)
{
+ if (!dev || !dev->remote)
+ return -EINVAL;
+
+ spin_lock(&dev->remote->lock);
if (dev->remote->users)
- return __saa7134_ir_start(dev);
+ __saa7134_ir_start(dev);
+ spin_unlock(&dev->remote->lock);
return 0;
}
void saa7134_ir_stop(struct saa7134_dev *dev)
{
+ if (!dev || !dev->remote)
+ return;
+
+ spin_lock(&dev->remote->lock);
if (dev->remote->users)
__saa7134_ir_stop(dev);
+ spin_unlock(&dev->remote->lock);
}
static int saa7134_ir_open(struct rc_dev *rc)
{
struct saa7134_dev *dev = rc->priv;
+ if (!dev || !dev->remote)
+ return -EINVAL;
+
+ spin_lock(&dev->remote->lock);
+ if (dev->remote->users == 0)
+ __saa7134_ir_start(dev);
dev->remote->users++;
- return __saa7134_ir_start(dev);
+ spin_unlock(&dev->remote->lock);
+
+ return 0;
}
static void saa7134_ir_close(struct rc_dev *rc)
{
struct saa7134_dev *dev = rc->priv;
+ if (!dev || !dev->remote)
+ return;
+
+ spin_lock(&dev->remote->lock);
dev->remote->users--;
- if (!dev->remote->users)
+ if (dev->remote->users == 0)
__saa7134_ir_stop(dev);
+ spin_unlock(&dev->remote->lock);
}
int saa7134_input_init1(struct saa7134_dev *dev)
@@ -744,6 +753,7 @@ int saa7134_input_init1(struct saa7134_dev *dev)
ir->mask_keyup = mask_keyup;
ir->polling = polling;
ir->raw_decode = raw_decode;
+ spin_lock_init(&ir->lock);
/* init input device */
snprintf(ir->name, sizeof(ir->name), "saa7134 IR (%s)",
diff --git a/drivers/media/video/saa7134/saa7134.h b/drivers/media/video/saa7134/saa7134.h
index babfbe7..7c836c3 100644
--- a/drivers/media/video/saa7134/saa7134.h
+++ b/drivers/media/video/saa7134/saa7134.h
@@ -125,6 +125,7 @@ struct saa7134_card_ir {
char name[32];
char phys[32];
unsigned users;
+ spinlock_t lock;
u32 polling;
u32 last_gpio;
next prev parent reply other threads:[~2010-11-19 23:44 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-11-19 23:42 [PATCH 00/10] rc-core: various cleanups David Härdeman
2010-11-19 23:42 ` [PATCH 01/10] saa7134: remove unused module parameter David Härdeman
2010-11-19 23:42 ` [PATCH 02/10] saa7134: use full keycode for BeholdTV David Härdeman
2010-11-19 23:42 ` [PATCH 03/10] saa7134: some minor cleanups David Härdeman
2010-11-19 23:42 ` [PATCH 04/10] saa7134: merge saa7134_card_ir->timer and saa7134_card_ir->timer_end David Härdeman
2010-11-19 23:43 ` David Härdeman [this message]
2010-11-19 23:43 ` [PATCH 06/10] saa7134: make module parameters boolean David Härdeman
2010-11-20 6:10 ` hermann pitton
2010-11-19 23:43 ` [PATCH 07/10] bttv: rename struct card_ir to bttv_ir David Härdeman
2010-11-19 23:43 ` [PATCH 08/10] bttv: merge ir decoding timers David Härdeman
2010-11-19 23:43 ` [PATCH 09/10] mceusb: int to bool conversion David Härdeman
2010-11-19 23:43 ` [PATCH 10/10] rc-core: fix some leftovers from the renaming patches David Härdeman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20101119234302.3511.97440.stgit@localhost.localdomain \
--to=david@hardeman.nu \
--cc=jarod@wilsonet.com \
--cc=linux-media@vger.kernel.org \
--cc=mchehab@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox