nvmem: core: support passing DT node in cell info

Some hardware may have NVMEM cells described in Device Tree using
individual nodes. Let drivers pass such nodes to the NVMEM subsystem so
they can be later used by NVMEM consumers.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20220429162701.2222-2-srinivas.kandagatla@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/nvmem/core.c

@@ -467,6 +467,7 @@ static int nvmem_cell_info_to_nvmem_cell_entry_nodup(struct nvmem_device *nvmem,
 
 	cell->bit_offset = info->bit_offset;
 	cell->nbits = info->nbits;
+	cell->np = info->np;
 
 	if (cell->nbits)
 		cell->bytes = DIV_ROUND_UP(cell->nbits + cell->bit_offset,

include/linux/nvmem-consumer.h

@@ -25,6 +25,7 @@ struct nvmem_cell_info {
 	unsigned int		bytes;
 	unsigned int		bit_offset;
 	unsigned int		nbits;
+	struct device_node	*np;
 };
 
 /**