nvmem: core: Notify when a new layout is registered

Tell listeners a new layout was introduced and is now available.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20230823132744.350618-23-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: miquelraynal

drivers/nvmem/core.c

@@ -771,12 +771,16 @@ int __nvmem_layout_register(struct nvmem_layout *layout, struct module *owner)
 	list_add(&layout->node, &nvmem_layouts);
 	spin_unlock(&nvmem_layout_lock);
 
+	blocking_notifier_call_chain(&nvmem_notifier, NVMEM_LAYOUT_ADD, layout);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(__nvmem_layout_register);
 
 void nvmem_layout_unregister(struct nvmem_layout *layout)
 {
+	blocking_notifier_call_chain(&nvmem_notifier, NVMEM_LAYOUT_REMOVE, layout);
+
 	spin_lock(&nvmem_layout_lock);
 	list_del(&layout->node);
 	spin_unlock(&nvmem_layout_lock);

include/linux/nvmem-consumer.h

@@ -43,6 +43,8 @@ enum {
 	NVMEM_REMOVE,
 	NVMEM_CELL_ADD,
 	NVMEM_CELL_REMOVE,
+	NVMEM_LAYOUT_ADD,
+	NVMEM_LAYOUT_REMOVE,
 };
 
 #if IS_ENABLED(CONFIG_NVMEM)