1 files changed, 72 insertions, 122 deletions

diff --git a/drivers/staging/most/mostcore/core.c b/drivers/staging/most/mostcore/core.c
index ed1ed25b6d1d..7c619feb12d3 100644
--- a/drivers/staging/most/mostcore/core.c
+++ b/drivers/staging/most/mostcore/core.c
@@ -35,7 +35,6 @@
 static struct class *most_class;
 static struct device *class_glue_dir;
 static struct ida mdev_id;
-static int modref;
 static int dummy_num_buffers;
 
 struct most_c_aim_obj {
@@ -66,7 +65,6 @@ struct most_c_obj {
 	struct most_c_aim_obj aim1;
 	struct list_head trash_fifo;
 	struct task_struct *hdm_enqueue_task;
-	struct mutex stop_task_mutex;
 	wait_queue_head_t hdm_fifo_wq;
 };
 
@@ -74,7 +72,6 @@ struct most_c_obj {
 
 struct most_inst_obj {
 	int dev_id;
-	atomic_t tainted;
 	struct most_interface *iface;
 	struct list_head channel_list;
 	struct most_c_obj *channel[MAX_CHANNELS];
@@ -82,6 +79,14 @@ struct most_inst_obj {
 	struct list_head list;
 };
 
+static const struct {
+	int most_ch_data_type;
+	char *name;
+} ch_data_type[] = { { MOST_CH_CONTROL, "control\n" },
+	{ MOST_CH_ASYNC, "async\n" },
+	{ MOST_CH_SYNC, "sync\n" },
+	{ MOST_CH_ISOC_AVP, "isoc_avp\n"} };
+
 #define to_inst_obj(d) container_of(d, struct most_inst_obj, kobj)
 
 /**
@@ -95,8 +100,6 @@ struct most_inst_obj {
 	_mbo;								\
 })
 
-static struct mutex deregister_mutex;
-
 /*		     ___	     ___
  *		     ___C H A N N E L___
  */
@@ -414,14 +417,12 @@ static ssize_t show_set_datatype(struct most_c_obj *c,
 				 struct most_c_attr *attr,
 				 char *buf)
 {
-	if (c->cfg.data_type & MOST_CH_CONTROL)
-		return snprintf(buf, PAGE_SIZE, "control\n");
-	else if (c->cfg.data_type & MOST_CH_ASYNC)
-		return snprintf(buf, PAGE_SIZE, "async\n");
-	else if (c->cfg.data_type & MOST_CH_SYNC)
-		return snprintf(buf, PAGE_SIZE, "sync\n");
-	else if (c->cfg.data_type & MOST_CH_ISOC_AVP)
-		return snprintf(buf, PAGE_SIZE, "isoc_avp\n");
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ch_data_type); i++) {
+		if (c->cfg.data_type & ch_data_type[i].most_ch_data_type)
+			return snprintf(buf, PAGE_SIZE, ch_data_type[i].name);
+	}
 	return snprintf(buf, PAGE_SIZE, "unconfigured\n");
 }
 
@@ -430,15 +431,16 @@ static ssize_t store_set_datatype(struct most_c_obj *c,
 				  const char *buf,
 				  size_t count)
 {
-	if (!strcmp(buf, "control\n")) {
-		c->cfg.data_type = MOST_CH_CONTROL;
-	} else if (!strcmp(buf, "async\n")) {
-		c->cfg.data_type = MOST_CH_ASYNC;
-	} else if (!strcmp(buf, "sync\n")) {
-		c->cfg.data_type = MOST_CH_SYNC;
-	} else if (!strcmp(buf, "isoc_avp\n")) {
-		c->cfg.data_type = MOST_CH_ISOC_AVP;
-	} else {
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ch_data_type); i++) {
+		if (!strcmp(buf, ch_data_type[i].name)) {
+			c->cfg.data_type = ch_data_type[i].most_ch_data_type;
+			break;
+		}
+	}
+
+	if (i == ARRAY_SIZE(ch_data_type)) {
 		pr_info("WARN: invalid attribute settings\n");
 		return -EINVAL;
 	}
@@ -551,29 +553,6 @@ create_most_c_obj(const char *name, struct kobject *parent)
 	return c;
 }
 
-/**
- * destroy_most_c_obj - channel release function
- * @c: pointer to channel object
- *
- * This decrements the reference counter of the channel object.
- * If the reference count turns zero, its release function is called.
- */
-static void destroy_most_c_obj(struct most_c_obj *c)
-{
-	if (c->aim0.ptr)
-		c->aim0.ptr->disconnect_channel(c->iface, c->channel_id);
-	if (c->aim1.ptr)
-		c->aim1.ptr->disconnect_channel(c->iface, c->channel_id);
-	c->aim0.ptr = NULL;
-	c->aim1.ptr = NULL;
-
-	mutex_lock(&deregister_mutex);
-	flush_trash_fifo(c);
-	flush_channel_fifos(c);
-	mutex_unlock(&deregister_mutex);
-	kobject_put(&c->kobj);
-}
-
 /*		     ___	       ___
  *		     ___I N S T A N C E___
  */
@@ -761,12 +740,10 @@ static void destroy_most_inst_obj(struct most_inst_obj *inst)
 {
 	struct most_c_obj *c, *tmp;
 
-	/* need to destroy channels first, since
-	 * each channel incremented the
-	 * reference count of the inst->kobj
-	 */
 	list_for_each_entry_safe(c, tmp, &inst->channel_list, list) {
-		destroy_most_c_obj(c);
+		flush_trash_fifo(c);
+		flush_channel_fifos(c);
+		kobject_put(&c->kobj);
 	}
 	kobject_put(&inst->kobj);
 }
@@ -1006,11 +983,14 @@ static ssize_t store_add_link(struct most_aim_obj *aim_obj,
 	else
 		return -ENOSPC;
 
+	*aim_ptr = aim_obj->driver;
 	ret = aim_obj->driver->probe_channel(c->iface, c->channel_id,
 					     &c->cfg, &c->kobj, mdev_devnod);
-	if (ret)
+	if (ret) {
+		*aim_ptr = NULL;
 		return ret;
-	*aim_ptr = aim_obj->driver;
+	}
+
 	return len;
 }
 
@@ -1056,12 +1036,12 @@ static ssize_t store_remove_link(struct most_aim_obj *aim_obj,
 	if (IS_ERR(c))
 		return -ENODEV;
 
+	if (aim_obj->driver->disconnect_channel(c->iface, c->channel_id))
+		return -EIO;
 	if (c->aim0.ptr == aim_obj->driver)
 		c->aim0.ptr = NULL;
 	if (c->aim1.ptr == aim_obj->driver)
 		c->aim1.ptr = NULL;
-	if (aim_obj->driver->disconnect_channel(c->iface, c->channel_id))
-		return -EIO;
 	return len;
 }
 
@@ -1279,7 +1259,6 @@ static int arm_mbo_chain(struct most_c_obj *c, int dir,
 	for (i = 0; i < c->cfg.num_buffers; i++) {
 		mbo = kzalloc(sizeof(*mbo), GFP_KERNEL);
 		if (!mbo) {
-			pr_info("WARN: Allocation of MBO failed.\n");
 			retval = i;
 			goto _exit;
 		}
@@ -1319,18 +1298,10 @@ _exit:
  */
 int most_submit_mbo(struct mbo *mbo)
 {
-	struct most_c_obj *c;
-	struct most_inst_obj *i;
-
 	if (unlikely((!mbo) || (!mbo->context))) {
 		pr_err("Bad MBO or missing channel reference\n");
 		return -EINVAL;
 	}
-	c = mbo->context;
-	i = c->inst;
-
-	if (unlikely(atomic_read(&i->tainted)))
-		return -ENODEV;
 
 	nq_hdm_mbo(mbo);
 	return 0;
@@ -1387,7 +1358,7 @@ most_c_obj *get_channel_by_iface(struct most_interface *iface, int id)
 	return i->channel[id];
 }
 
-int channel_has_mbo(struct most_interface *iface, int id)
+int channel_has_mbo(struct most_interface *iface, int id, struct most_aim *aim)
 {
 	struct most_c_obj *c = get_channel_by_iface(iface, id);
 	unsigned long flags;
@@ -1396,6 +1367,11 @@ int channel_has_mbo(struct most_interface *iface, int id)
 	if (unlikely(!c))
 		return -EINVAL;
 
+	if (c->aim0.refs && c->aim1.refs &&
+	    ((aim == c->aim0.ptr && c->aim0.num_buffers <= 0) ||
+	     (aim == c->aim1.ptr && c->aim1.num_buffers <= 0)))
+		return 0;
+
 	spin_lock_irqsave(&c->fifo_lock, flags);
 	empty = list_empty(&c->fifo);
 	spin_unlock_irqrestore(&c->fifo_lock, flags);
@@ -1456,17 +1432,8 @@ EXPORT_SYMBOL_GPL(most_get_mbo);
  */
 void most_put_mbo(struct mbo *mbo)
 {
-	struct most_c_obj *c;
-	struct most_inst_obj *i;
-
-	c = mbo->context;
-	i = c->inst;
+	struct most_c_obj *c = mbo->context;
 
-	if (unlikely(atomic_read(&i->tainted))) {
-		mbo->status = MBO_E_CLOSE;
-		trash_mbo(mbo);
-		return;
-	}
 	if (c->cfg.direction == MOST_CH_TX) {
 		arm_mbo(mbo);
 		return;
@@ -1546,7 +1513,6 @@ int most_start_channel(struct most_interface *iface, int id,
 		mutex_unlock(&c->start_mutex);
 		return -ENOLCK;
 	}
-	modref++;
 
 	c->cfg.extra_len = 0;
 	if (c->iface->configure(c->iface, c->channel_id, &c->cfg)) {
@@ -1588,7 +1554,6 @@ out:
 
 error:
 	module_put(iface->mod);
-	modref--;
 	mutex_unlock(&c->start_mutex);
 	return ret;
 }
@@ -1616,24 +1581,12 @@ int most_stop_channel(struct most_interface *iface, int id,
 	if (c->aim0.refs + c->aim1.refs >= 2)
 		goto out;
 
-	mutex_lock(&c->stop_task_mutex);
 	if (c->hdm_enqueue_task)
 		kthread_stop(c->hdm_enqueue_task);
 	c->hdm_enqueue_task = NULL;
-	mutex_unlock(&c->stop_task_mutex);
 
-	mutex_lock(&deregister_mutex);
-	if (atomic_read(&c->inst->tainted)) {
-		mutex_unlock(&deregister_mutex);
-		mutex_unlock(&c->start_mutex);
-		return -ENODEV;
-	}
-	mutex_unlock(&deregister_mutex);
-
-	if (iface->mod && modref) {
+	if (iface->mod)
 		module_put(iface->mod);
-		modref--;
-	}
 
 	c->is_poisoned = true;
 	if (c->iface->poison_channel(c->iface, c->channel_id)) {
@@ -1762,6 +1715,7 @@ struct kobject *most_register_interface(struct most_interface *iface)
 	inst = create_most_inst_obj(name);
 	if (!inst) {
 		pr_info("Failed to allocate interface instance\n");
+		ida_simple_remove(&mdev_id, id);
 		return ERR_PTR(-ENOMEM);
 	}
 
@@ -1769,7 +1723,6 @@ struct kobject *most_register_interface(struct most_interface *iface)
 	INIT_LIST_HEAD(&inst->channel_list);
 	inst->iface = iface;
 	inst->dev_id = id;
-	atomic_set(&inst->tainted, 0);
 	list_add_tail(&inst->list, &instance_list);
 
 	for (i = 0; i < iface->num_channels; i++) {
@@ -1808,7 +1761,6 @@ struct kobject *most_register_interface(struct most_interface *iface)
 		init_completion(&c->cleanup);
 		atomic_set(&c->mbo_ref, 0);
 		mutex_init(&c->start_mutex);
-		mutex_init(&c->stop_task_mutex);
 		list_add_tail(&c->list, &inst->channel_list);
 	}
 	pr_info("registered new MOST device mdev%d (%s)\n",
@@ -1818,6 +1770,7 @@ struct kobject *most_register_interface(struct most_interface *iface)
 free_instance:
 	pr_info("Failed allocate channel(s)\n");
 	list_del(&inst->list);
+	ida_simple_remove(&mdev_id, id);
 	destroy_most_inst_obj(inst);
 	return ERR_PTR(-ENOMEM);
 }
@@ -1835,37 +1788,24 @@ void most_deregister_interface(struct most_interface *iface)
 	struct most_inst_obj *i = iface->priv;
 	struct most_c_obj *c;
 
-	mutex_lock(&deregister_mutex);
 	if (unlikely(!i)) {
 		pr_info("Bad Interface\n");
-		mutex_unlock(&deregister_mutex);
 		return;
 	}
 	pr_info("deregistering MOST device %s (%s)\n", i->kobj.name,
 		iface->description);
 
-	atomic_set(&i->tainted, 1);
-	mutex_unlock(&deregister_mutex);
-
-	while (modref) {
-		if (iface->mod && modref)
-			module_put(iface->mod);
-		modref--;
-	}
-
 	list_for_each_entry(c, &i->channel_list, list) {
-		if (c->aim0.refs + c->aim1.refs <= 0)
-			continue;
-
-		mutex_lock(&c->stop_task_mutex);
-		if (c->hdm_enqueue_task)
-			kthread_stop(c->hdm_enqueue_task);
-		c->hdm_enqueue_task = NULL;
-		mutex_unlock(&c->stop_task_mutex);
-
-		if (iface->poison_channel(iface, c->channel_id))
-			pr_err("Can't poison channel %d\n", c->channel_id);
+		if (c->aim0.ptr)
+			c->aim0.ptr->disconnect_channel(c->iface,
+							c->channel_id);
+		if (c->aim1.ptr)
+			c->aim1.ptr->disconnect_channel(c->iface,
+							c->channel_id);
+		c->aim0.ptr = NULL;
+		c->aim1.ptr = NULL;
 	}
+
 	ida_simple_remove(&mdev_id, i->dev_id);
 	list_del(&i->list);
 	destroy_most_inst_obj(i);
@@ -1913,41 +1853,52 @@ EXPORT_SYMBOL_GPL(most_resume_enqueue);
 
 static int __init most_init(void)
 {
+	int err;
+
 	pr_info("init()\n");
 	INIT_LIST_HEAD(&instance_list);
 	INIT_LIST_HEAD(&aim_list);
-	mutex_init(&deregister_mutex);
 	ida_init(&mdev_id);
 
-	if (bus_register(&most_bus)) {
+	err = bus_register(&most_bus);
+	if (err) {
 		pr_info("Cannot register most bus\n");
-		goto exit;
+		return err;
 	}
 
 	most_class = class_create(THIS_MODULE, "most");
 	if (IS_ERR(most_class)) {
 		pr_info("No udev support.\n");
+		err = PTR_ERR(most_class);
 		goto exit_bus;
 	}
-	if (driver_register(&mostcore)) {
+
+	err = driver_register(&mostcore);
+	if (err) {
 		pr_info("Cannot register core driver\n");
 		goto exit_class;
 	}
 
 	class_glue_dir =
 		device_create(most_class, NULL, 0, NULL, "mostcore");
-	if (!class_glue_dir)
+	if (IS_ERR(class_glue_dir)) {
+		err = PTR_ERR(class_glue_dir);
 		goto exit_driver;
+	}
 
 	most_aim_kset =
 		kset_create_and_add("aims", NULL, &class_glue_dir->kobj);
-	if (!most_aim_kset)
+	if (!most_aim_kset) {
+		err = -ENOMEM;
 		goto exit_class_container;
+	}
 
 	most_inst_kset =
 		kset_create_and_add("devices", NULL, &class_glue_dir->kobj);
-	if (!most_inst_kset)
+	if (!most_inst_kset) {
+		err = -ENOMEM;
 		goto exit_driver_kset;
+	}
 
 	return 0;
 
@@ -1961,8 +1912,7 @@ exit_class:
 	class_destroy(most_class);
 exit_bus:
 	bus_unregister(&most_bus);
-exit:
-	return -ENOMEM;
+	return err;
 }
 
 static void __exit most_exit(void)