ptp: ocp: handle error from nvmem_device_find

nvmem_device_find returns a valid pointer or IS_ERR().
Handle this properly.

Fixes: 0cfcdd1ebcfe ("ptp: ocp: add nvmem interface for accessing eeprom")
Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Link: https://lore.kernel.org/r/20220329160354.4035-1-jonathan.lemon@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/ptp/ptp_ocp.c b/drivers/ptp/ptp_ocp.c
index c3d0fcf..0feaa4b 100644 (file)
--- a/drivers/ptp/ptp_ocp.c
+++ b/drivers/ptp/ptp_ocp.c
@@ -1214,10 +1214,9 @@ ptp_ocp_nvmem_device_get(struct ptp_ocp *bp, const void * const tag)
 static inline void
 ptp_ocp_nvmem_device_put(struct nvmem_device **nvmemp)
 {
-       if (*nvmemp != NULL) {
+       if (!IS_ERR_OR_NULL(*nvmemp))
                nvmem_device_put(*nvmemp);
-               *nvmemp = NULL;
-       }
+       *nvmemp = NULL;
 }
 
 static void
@@ -1241,13 +1240,15 @@ ptp_ocp_read_eeprom(struct ptp_ocp *bp)
                }
                if (!nvmem) {
                        nvmem = ptp_ocp_nvmem_device_get(bp, tag);
-                       if (!nvmem)
-                               goto out;
+                       if (IS_ERR(nvmem)) {
+                               ret = PTR_ERR(nvmem);
+                               goto fail;
+                       }
                }
                ret = nvmem_device_read(nvmem, map->off, map->len,
                                        BP_MAP_ENTRY_ADDR(bp, map));
                if (ret != map->len)
-                       goto read_fail;
+                       goto fail;
        }
 
        bp->has_eeprom_data = true;
@@ -1256,7 +1257,7 @@ out:
        ptp_ocp_nvmem_device_put(&nvmem);
        return;
 
-read_fail:
+fail:
        dev_err(&bp->pdev->dev, "could not read eeprom: %d\n", ret);
        goto out;
 }