[PATCH v3 1/3] nvmem: core: allow to register cells during nvmem registration

[Vadym Kochan]

Add NVMEM_PRE_ADD notification step which is called before any cells
binding - from lookup table or config, this allows to register cells
in some specific layout (tlv) which should be parsed first and then
registered. So there might be a cell parser driver which can register
lookup table during this notification step.

Signed-off-by: Vadym Kochan <vadym.kochan@xxxxxxxxxxx>
---
v3:
    1) Update core.c changes by extending notification mechanism
       by adding new NVMEM_PRE_ADD event id which is called before lookup
       table cells binding, this allows for notification handler to
       register cells which require nvmem parsing.

 drivers/nvmem/core.c           | 2 ++
 include/linux/nvmem-consumer.h | 1 +
 2 files changed, 3 insertions(+)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 6cd3edb2eaf6..c48a69e0ebbe 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -668,6 +668,8 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
 			goto err_device_del;
 	}
 
+	blocking_notifier_call_chain(&nvmem_notifier, NVMEM_PRE_ADD, nvmem);
+
 	if (config->cells) {
 		rval = nvmem_add_cells(nvmem, config->cells, config->ncells);
 		if (rval)
diff --git a/include/linux/nvmem-consumer.h b/include/linux/nvmem-consumer.h
index 052293f4cbdb..0f7107276756 100644
--- a/include/linux/nvmem-consumer.h
+++ b/include/linux/nvmem-consumer.h
@@ -50,6 +50,7 @@ enum {
 	NVMEM_REMOVE,
 	NVMEM_CELL_ADD,
 	NVMEM_CELL_REMOVE,
+	NVMEM_PRE_ADD,
 };
 
 #if IS_ENABLED(CONFIG_NVMEM)
-- 
2.17.1