nvmem: fix nvmem_cell_get_from_lookup()

From: Bartosz Golaszewski <[email protected]>

We check if the pointer returned by __nvmem_device_get() is not NULL while we should actually check if it is not IS_ERR(nvmem). Fix it.

While we're at it: fix the next error path where we should assign an error value to cell before returning.

Signed-off-by Bartosz Golaszewski <[email protected]>

Reported-by Stephen Rothwell <[email protected]>

---
v1 -> v2:
- use ERR_CAST() instead of a direct pointer cast

v2 -> v3:
- added the Reported-by tag

  drivers/nvmem/core.c | 5 +++--
  1 file changed, 3 insertions(+), 2 deletions(-)

drivers/nvmem/core.c +3 -2

index ad1227df1984..f49474e1ad49 100644
@@ -952,9 +952,9 @@ nvmem_cell_get_from_lookup(struct device *dev, const char *con_id)
  		    (strcmp(lookup->con_id, con_id) == 0)) {
  			/* This is the right entry. */
  			nvmem = __nvmem_device_get(NULL, lookup->nvmem_name);
-			if (!nvmem) {
+			if (IS_ERR(nvmem)) {
  				/* Provider may not be registered yet. */
-				cell = ERR_PTR(-EPROBE_DEFER);
+				cell = ERR_CAST(nvmem);
  				goto out;
  			}
 

@@ -962,6 +962,7 @@ nvmem_cell_get_from_lookup(struct device *dev, const char *con_id)
  						       lookup->cell_name);
  			if (!cell) {
  				__nvmem_device_put(nvmem);
+				cell = ERR_PTR(-ENOENT);
  				goto out;
  			}
  		}