Function nvmem_reg_read can return a non zero value indicating an error.
This returned value must be read and error propagated to
nvmem_cell_prepare_write_buffer. Silence the following gcc warning (W=1):

  drivers/nvmem/core.c:1093:9: warning: variable ‘rc’ set but not used 
[-Wunused-but-set-variable]

Signed-off-by: Mathieu Malaterre <[email protected]>
---
v2: prefer ERR_PTR(-EINVAL) over a simple return NULL

 drivers/nvmem/core.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index b05aa8e81303..f7b6c85cf393 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -1107,6 +1107,8 @@ static void *nvmem_cell_prepare_write_buffer(struct 
nvmem_cell *cell,
 
                /* setup the first byte with lsb bits from nvmem */
                rc = nvmem_reg_read(nvmem, cell->offset, &v, 1);
+               if (rc)
+                       goto err;
                *b++ |= GENMASK(bit_offset - 1, 0) & v;
 
                /* setup rest of the byte if any */
@@ -1125,11 +1127,16 @@ static void *nvmem_cell_prepare_write_buffer(struct 
nvmem_cell *cell,
                /* setup the last byte with msb bits from nvmem */
                rc = nvmem_reg_read(nvmem,
                                    cell->offset + cell->bytes - 1, &v, 1);
+               if (rc)
+                       goto err;
                *p |= GENMASK(7, (nbits + bit_offset) % BITS_PER_BYTE) & v;
 
        }
 
        return buf;
+err:
+       kfree(buf);
+       return ERR_PTR(-EINVAL);
 }
 
 /**
-- 
2.11.0

Reply via email to