V4L/DVB (6636): xc2028: protect device list

Protect refcount changes and modifications to xc2028_list with a mutex.

Signed-off-by: Chris Pascoe <c.pascoe@itee.uq.edu.au>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
Chris Pascoe 2007-11-19 04:45:38 -03:00 committed by Mauro Carvalho Chehab
parent 91240dd924
commit aa501be989
1 changed files with 13 additions and 1 deletions

View File

@ -44,6 +44,8 @@ MODULE_PARM_DESC(audio_std,
"NICAM/B\n");
static LIST_HEAD(xc2028_list);
static DEFINE_MUTEX(xc2028_list_mutex);
/* struct for storing firmware table */
struct firmware_description {
unsigned int type;
@ -854,6 +856,8 @@ static int xc2028_dvb_release(struct dvb_frontend *fe)
tuner_dbg("%s called\n", __FUNCTION__);
mutex_lock(&xc2028_list_mutex);
priv->count--;
if (!priv->count) {
@ -865,6 +869,8 @@ static int xc2028_dvb_release(struct dvb_frontend *fe)
kfree(priv);
}
mutex_unlock(&xc2028_list_mutex);
return 0;
}
@ -940,6 +946,8 @@ void *xc2028_attach(struct dvb_frontend *fe, struct xc2028_config *cfg)
video_dev = cfg->video_dev;
mutex_lock(&xc2028_list_mutex);
list_for_each_entry(priv, &xc2028_list, xc2028_list) {
if (priv->video_dev == cfg->video_dev) {
video_dev = NULL;
@ -949,8 +957,10 @@ void *xc2028_attach(struct dvb_frontend *fe, struct xc2028_config *cfg)
if (video_dev) {
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (priv == NULL)
if (priv == NULL) {
mutex_unlock(&xc2028_list_mutex);
return NULL;
}
priv->bandwidth = BANDWIDTH_6_MHZ;
priv->need_load_generic = 1;
@ -974,6 +984,8 @@ void *xc2028_attach(struct dvb_frontend *fe, struct xc2028_config *cfg)
tuner_info("type set to %s\n", "XCeive xc2028/xc3028 tuner");
mutex_unlock(&xc2028_list_mutex);
return fe;
}