[PATCH v2 1/2] nvmem: core: allow to register cells for existing device

[Vadym Kochan]

Current implementation does not allow to register nvmem cells for
existing device and requires that this will be done before device is
registered.

But there might a driver which provides only cells info which needs to
be added for already registered nvmem device.

Signed-off-by: Vadym Kochan <vadym.koc...@plvision.eu>
---
 drivers/nvmem/core.c | 59 +++++++++++++++++++++++++++-----------------
 1 file changed, 37 insertions(+), 22 deletions(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 05c6ae4b0b97..39c9df9ae9a0 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -482,35 +482,43 @@ int nvmem_unregister_notifier(struct notifier_block *nb)
 }
 EXPORT_SYMBOL_GPL(nvmem_unregister_notifier);
 
-static int nvmem_add_cells_from_table(struct nvmem_device *nvmem)
+static int __nvmem_add_cells_from_table(struct nvmem_device *nvmem,
+                                       struct nvmem_cell_table *table)
 {
        const struct nvmem_cell_info *info;
-       struct nvmem_cell_table *table;
        struct nvmem_cell *cell;
-       int rval = 0, i;
+       int err, i;
+
+       for (i = 0; i < table->ncells; i++) {
+               info = &table->cells[i];
+
+               cell = kzalloc(sizeof(*cell), GFP_KERNEL);
+               if (!cell)
+                       return -ENOMEM;
+
+               err = nvmem_cell_info_to_nvmem_cell(nvmem, info, cell);
+               if (err) {
+                       kfree(cell);
+                       return err;
+               }
+
+               nvmem_cell_add(cell);
+       }
+
+       return 0;
+}
+
+static int nvmem_add_cells_from_table(struct nvmem_device *nvmem)
+{
+       struct nvmem_cell_table *table;
+       int rval = 0;
 
        mutex_lock(&nvmem_cell_mutex);
        list_for_each_entry(table, &nvmem_cell_tables, node) {
                if (strcmp(nvmem_dev_name(nvmem), table->nvmem_name) == 0) {
-                       for (i = 0; i < table->ncells; i++) {
-                               info = &table->cells[i];
-
-                               cell = kzalloc(sizeof(*cell), GFP_KERNEL);
-                               if (!cell) {
-                                       rval = -ENOMEM;
-                                       goto out;
-                               }
-
-                               rval = nvmem_cell_info_to_nvmem_cell(nvmem,
-                                                                    info,
-                                                                    cell);
-                               if (rval) {
-                                       kfree(cell);
-                                       goto out;
-                               }
-
-                               nvmem_cell_add(cell);
-                       }
+                       rval = __nvmem_add_cells_from_table(nvmem, table);
+                       if (rval)
+                               goto out;
                }
        }
 
@@ -1560,6 +1568,13 @@ EXPORT_SYMBOL_GPL(nvmem_device_write);
  */
 void nvmem_add_cell_table(struct nvmem_cell_table *table)
 {
+       const char *dev_name = table->nvmem_name;
+       struct nvmem_device *nvmem;
+
+       nvmem = __nvmem_device_get((void *)dev_name, device_match_name);
+       if (nvmem)
+               __nvmem_add_cells_from_table(nvmem, table);
+
        mutex_lock(&nvmem_cell_mutex);
        list_add_tail(&table->node, &nvmem_cell_tables);
        mutex_unlock(&nvmem_cell_mutex);
-- 
2.17.1