1 files changed, 130 insertions, 0 deletions
diff --git a/drivers/media/cec/cec-notifier.c b/drivers/media/cec/cec-notifier.c
new file mode 100644
index 0000000..74dc1c3
--- /dev/null
+++ b/drivers/media/cec/cec-notifier.c
@@ -0,0 +1,130 @@
+/*
+ * cec-notifier.c - notify CEC drivers of physical address changes
+ *
+ * Copyright 2016 Russell King <rmk+kernel@arm.linux.org.uk>
+ * Copyright 2016-2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/export.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/kref.h>
+
+#include <media/cec.h>
+#include <media/cec-notifier.h>
+#include <drm/drm_edid.h>
+
+struct cec_notifier {
+	struct mutex lock;
+	struct list_head head;
+	struct kref kref;
+	struct device *dev;
+	struct cec_adapter *cec_adap;
+	void (*callback)(struct cec_adapter *adap, u16 pa);
+
+	u16 phys_addr;
+};
+
+static LIST_HEAD(cec_notifiers);
+static DEFINE_MUTEX(cec_notifiers_lock);
+
+struct cec_notifier *cec_notifier_get(struct device *dev)
+{
+	struct cec_notifier *n;
+
+	mutex_lock(&cec_notifiers_lock);
+	list_for_each_entry(n, &cec_notifiers, head) {
+		if (n->dev == dev) {
+			kref_get(&n->kref);
+			mutex_unlock(&cec_notifiers_lock);
+			return n;
+		}
+	}
+	n = kzalloc(sizeof(*n), GFP_KERNEL);
+	if (!n)
+		goto unlock;
+	n->dev = dev;
+	n->phys_addr = CEC_PHYS_ADDR_INVALID;
+	mutex_init(&n->lock);
+	kref_init(&n->kref);
+	list_add_tail(&n->head, &cec_notifiers);
+unlock:
+	mutex_unlock(&cec_notifiers_lock);
+	return n;
+}
+EXPORT_SYMBOL_GPL(cec_notifier_get);
+
+static void cec_notifier_release(struct kref *kref)
+{
+	struct cec_notifier *n =
+		container_of(kref, struct cec_notifier, kref);
+
+	list_del(&n->head);
+	kfree(n);
+}
+
+void cec_notifier_put(struct cec_notifier *n)
+{
+	mutex_lock(&cec_notifiers_lock);
+	kref_put(&n->kref, cec_notifier_release);
+	mutex_unlock(&cec_notifiers_lock);
+}
+EXPORT_SYMBOL_GPL(cec_notifier_put);
+
+void cec_notifier_set_phys_addr(struct cec_notifier *n, u16 pa)
+{
+	mutex_lock(&n->lock);
+	n->phys_addr = pa;
+	if (n->callback)
+		n->callback(n->cec_adap, n->phys_addr);
+	mutex_unlock(&n->lock);
+}
+EXPORT_SYMBOL_GPL(cec_notifier_set_phys_addr);
+
+void cec_notifier_set_phys_addr_from_edid(struct cec_notifier *n,
+					  const struct edid *edid)
+{
+	u16 pa = CEC_PHYS_ADDR_INVALID;
+
+	if (edid && edid->extensions)
+		pa = cec_get_edid_phys_addr((const u8 *)edid,
+				EDID_LENGTH * (edid->extensions + 1), NULL);
+	cec_notifier_set_phys_addr(n, pa);
+}
+EXPORT_SYMBOL_GPL(cec_notifier_set_phys_addr_from_edid);
+
+void cec_notifier_register(struct cec_notifier *n,
+			   struct cec_adapter *adap,
+			   void (*callback)(struct cec_adapter *adap, u16 pa))
+{
+	kref_get(&n->kref);
+	mutex_lock(&n->lock);
+	n->cec_adap = adap;
+	n->callback = callback;
+	n->callback(adap, n->phys_addr);
+	mutex_unlock(&n->lock);
+}
+EXPORT_SYMBOL_GPL(cec_notifier_register);
+
+void cec_notifier_unregister(struct cec_notifier *n)
+{
+	mutex_lock(&n->lock);
+	n->callback = NULL;
+	mutex_unlock(&n->lock);
+	cec_notifier_put(n);
+}
+EXPORT_SYMBOL_GPL(cec_notifier_unregister);