From: Sakari Ailus Date: Wed, 25 Jan 2012 00:05:34 +0000 (-0300) Subject: [media] v4l: Allow changing control handler lock X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=77e7c4e624404c6edb5686b3d5f873c6008ed6b0;p=linux-beck.git [media] v4l: Allow changing control handler lock Allow choosing the lock used by the control handler. This may be handy sometimes when a driver providing multiple subdevs does not want to use several locks to serialise its functions. Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/media/video/adp1653.c b/drivers/media/video/adp1653.c index 24afc99d26e4..57e87090388d 100644 --- a/drivers/media/video/adp1653.c +++ b/drivers/media/video/adp1653.c @@ -281,19 +281,19 @@ adp1653_init_device(struct adp1653_flash *flash) return -EIO; } - mutex_lock(&flash->ctrls.lock); + mutex_lock(flash->ctrls.lock); /* Reset faults before reading new ones. */ flash->fault = 0; rval = adp1653_get_fault(flash); - mutex_unlock(&flash->ctrls.lock); + mutex_unlock(flash->ctrls.lock); if (rval > 0) { dev_err(&client->dev, "faults detected: 0x%1.1x\n", rval); return -EIO; } - mutex_lock(&flash->ctrls.lock); + mutex_lock(flash->ctrls.lock); rval = adp1653_update_hw(flash); - mutex_unlock(&flash->ctrls.lock); + mutex_unlock(flash->ctrls.lock); if (rval) { dev_err(&client->dev, "adp1653_update_hw failed at %s\n", __func__); diff --git a/drivers/media/video/v4l2-ctrls.c b/drivers/media/video/v4l2-ctrls.c index edb2a6a066ca..e5531ace5ee7 100644 --- a/drivers/media/video/v4l2-ctrls.c +++ b/drivers/media/video/v4l2-ctrls.c @@ -1177,7 +1177,8 @@ static inline int handler_set_err(struct v4l2_ctrl_handler *hdl, int err) int v4l2_ctrl_handler_init(struct v4l2_ctrl_handler *hdl, unsigned nr_of_controls_hint) { - mutex_init(&hdl->lock); + hdl->lock = &hdl->_lock; + mutex_init(hdl->lock); INIT_LIST_HEAD(&hdl->ctrls); INIT_LIST_HEAD(&hdl->ctrl_refs); hdl->nr_of_buckets = 1 + nr_of_controls_hint / 8; @@ -1198,7 +1199,7 @@ void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl) if (hdl == NULL || hdl->buckets == NULL) return; - mutex_lock(&hdl->lock); + mutex_lock(hdl->lock); /* Free all nodes */ list_for_each_entry_safe(ref, next_ref, &hdl->ctrl_refs, node) { list_del(&ref->node); @@ -1215,7 +1216,7 @@ void v4l2_ctrl_handler_free(struct v4l2_ctrl_handler *hdl) hdl->buckets = NULL; hdl->cached = NULL; hdl->error = 0; - mutex_unlock(&hdl->lock); + mutex_unlock(hdl->lock); } EXPORT_SYMBOL(v4l2_ctrl_handler_free); @@ -1280,9 +1281,9 @@ static struct v4l2_ctrl_ref *find_ref_lock( struct v4l2_ctrl_ref *ref = NULL; if (hdl) { - mutex_lock(&hdl->lock); + mutex_lock(hdl->lock); ref = find_ref(hdl, id); - mutex_unlock(&hdl->lock); + mutex_unlock(hdl->lock); } return ref; } @@ -1329,7 +1330,7 @@ static int handler_new_ref(struct v4l2_ctrl_handler *hdl, INIT_LIST_HEAD(&new_ref->node); - mutex_lock(&hdl->lock); + mutex_lock(hdl->lock); /* Add immediately at the end of the list if the list is empty, or if the last element in the list has a lower ID. @@ -1359,7 +1360,7 @@ insert_in_hash: hdl->buckets[bucket] = new_ref; unlock: - mutex_unlock(&hdl->lock); + mutex_unlock(hdl->lock); return 0; } @@ -1445,9 +1446,9 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl, kfree(ctrl); return NULL; } - mutex_lock(&hdl->lock); + mutex_lock(hdl->lock); list_add_tail(&ctrl->node, &hdl->ctrls); - mutex_unlock(&hdl->lock); + mutex_unlock(hdl->lock); return ctrl; } @@ -1564,7 +1565,7 @@ int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl, return 0; if (hdl->error) return hdl->error; - mutex_lock(&add->lock); + mutex_lock(add->lock); list_for_each_entry(ref, &add->ctrl_refs, node) { struct v4l2_ctrl *ctrl = ref->ctrl; @@ -1578,7 +1579,7 @@ int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl, if (ret) break; } - mutex_unlock(&add->lock); + mutex_unlock(add->lock); return ret; } EXPORT_SYMBOL(v4l2_ctrl_add_handler); @@ -1742,11 +1743,11 @@ void v4l2_ctrl_handler_log_status(struct v4l2_ctrl_handler *hdl, len = strlen(prefix); if (len && prefix[len - 1] != ' ') colon = ": "; - mutex_lock(&hdl->lock); + mutex_lock(hdl->lock); list_for_each_entry(ctrl, &hdl->ctrls, node) if (!(ctrl->flags & V4L2_CTRL_FLAG_DISABLED)) log_ctrl(ctrl, prefix, colon); - mutex_unlock(&hdl->lock); + mutex_unlock(hdl->lock); } EXPORT_SYMBOL(v4l2_ctrl_handler_log_status); @@ -1758,7 +1759,7 @@ int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl) if (hdl == NULL) return 0; - mutex_lock(&hdl->lock); + mutex_lock(hdl->lock); list_for_each_entry(ctrl, &hdl->ctrls, node) ctrl->done = false; @@ -1783,7 +1784,7 @@ int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl) if (ret) break; } - mutex_unlock(&hdl->lock); + mutex_unlock(hdl->lock); return ret; } EXPORT_SYMBOL(v4l2_ctrl_handler_setup); @@ -1798,7 +1799,7 @@ int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc) if (hdl == NULL) return -EINVAL; - mutex_lock(&hdl->lock); + mutex_lock(hdl->lock); /* Try to find it */ ref = find_ref(hdl, id); @@ -1823,7 +1824,7 @@ int v4l2_queryctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_queryctrl *qc) break; } } - mutex_unlock(&hdl->lock); + mutex_unlock(hdl->lock); if (!ref) return -EINVAL; @@ -2000,7 +2001,7 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl, belong to the same cluster. */ /* This has to be done with the handler lock taken. */ - mutex_lock(&hdl->lock); + mutex_lock(hdl->lock); /* First zero the helper field in the master control references */ for (i = 0; i < cs->count; i++) @@ -2022,7 +2023,7 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl, /* Point the mref helper to the current helper struct. */ mref->helper = h; } - mutex_unlock(&hdl->lock); + mutex_unlock(hdl->lock); return 0; } diff --git a/drivers/media/video/vivi.c b/drivers/media/video/vivi.c index d64d482f4f6b..6f2e354a242d 100644 --- a/drivers/media/video/vivi.c +++ b/drivers/media/video/vivi.c @@ -485,7 +485,7 @@ static void vivi_fillbuff(struct vivi_dev *dev, struct vivi_buffer *buf) gen_text(dev, vbuf, line++ * 16, 16, str); gain = v4l2_ctrl_g_ctrl(dev->gain); - mutex_lock(&dev->ctrl_handler.lock); + mutex_lock(dev->ctrl_handler.lock); snprintf(str, sizeof(str), " brightness %3d, contrast %3d, saturation %3d, hue %d ", dev->brightness->cur.val, dev->contrast->cur.val, @@ -509,7 +509,7 @@ static void vivi_fillbuff(struct vivi_dev *dev, struct vivi_buffer *buf) dev->int_menu->qmenu_int[dev->int_menu->cur.val], dev->int_menu->cur.val); gen_text(dev, vbuf, line++ * 16, 16, str); - mutex_unlock(&dev->ctrl_handler.lock); + mutex_unlock(dev->ctrl_handler.lock); if (dev->button_pressed) { dev->button_pressed--; snprintf(str, sizeof(str), " button pressed!"); diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h index c6f6b4c2c5f2..dde6fbacc271 100644 --- a/include/media/v4l2-ctrls.h +++ b/include/media/v4l2-ctrls.h @@ -167,7 +167,9 @@ struct v4l2_ctrl_ref { /** struct v4l2_ctrl_handler - The control handler keeps track of all the * controls: both the controls owned by the handler and those inherited * from other handlers. + * @_lock: Default for "lock". * @lock: Lock to control access to this handler and its controls. + * May be replaced by the user right after init. * @ctrls: The list of controls owned by this handler. * @ctrl_refs: The list of control references. * @cached: The last found control reference. It is common that the same @@ -178,7 +180,8 @@ struct v4l2_ctrl_ref { * @error: The error code of the first failed control addition. */ struct v4l2_ctrl_handler { - struct mutex lock; + struct mutex _lock; + struct mutex *lock; struct list_head ctrls; struct list_head ctrl_refs; struct v4l2_ctrl_ref *cached; @@ -455,7 +458,7 @@ void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed); */ static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl) { - mutex_lock(&ctrl->handler->lock); + mutex_lock(ctrl->handler->lock); } /** v4l2_ctrl_lock() - Helper function to unlock the handler @@ -464,7 +467,7 @@ static inline void v4l2_ctrl_lock(struct v4l2_ctrl *ctrl) */ static inline void v4l2_ctrl_unlock(struct v4l2_ctrl *ctrl) { - mutex_unlock(&ctrl->handler->lock); + mutex_unlock(ctrl->handler->lock); } /** v4l2_ctrl_g_ctrl() - Helper function to get the control's value from within a driver.