[PATCH v5 02/10] mtd: powernv_flash: Don't treat OPAL_SUCCESS as an error

[Cyril Bur]

While this driver expects to interact asynchronously, OPAL is well
within its rights to return OPAL_SUCCESS to indicate that the operation
completed without the need for a callback. We shouldn't treat
OPAL_SUCCESS as an error rather we should wrap up and return promptly to
the caller.

Signed-off-by: Cyril Bur <cyril...@gmail.com>
Acked-by: Boris Brezillon <boris.brezil...@free-electrons.com>
---
I'll note here that currently no OPAL exists that will return
OPAL_SUCCESS so there isn't the possibility of a bug today.
---
 drivers/mtd/devices/powernv_flash.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/devices/powernv_flash.c 
b/drivers/mtd/devices/powernv_flash.c
index f9ec38281ff2..ca3ca6adf71e 100644
--- a/drivers/mtd/devices/powernv_flash.c
+++ b/drivers/mtd/devices/powernv_flash.c
@@ -63,7 +63,6 @@ static int powernv_flash_async_op(struct mtd_info *mtd, enum 
flash_op op,
        if (token < 0) {
                if (token != -ERESTARTSYS)
                        dev_err(dev, "Failed to get an async token\n");
-
                return token;
        }
 
@@ -83,21 +82,25 @@ static int powernv_flash_async_op(struct mtd_info *mtd, 
enum flash_op op,
                return -EIO;
        }
 
+       if (rc == OPAL_SUCCESS)
+               goto out_success;
+
        if (rc != OPAL_ASYNC_COMPLETION) {
                dev_err(dev, "opal_flash_async_op(op=%d) failed (rc %d)\n",
                                op, rc);
-               opal_async_release_token(token);
-               return -EIO;
+               rc = -EIO;
+               goto out;
        }
 
        rc = opal_async_wait_response(token, &msg);
-       opal_async_release_token(token);
        if (rc) {
                dev_err(dev, "opal async wait failed (rc %d)\n", rc);
-               return -EIO;
+               rc = -EIO;
+               goto out;
        }
 
        rc = opal_get_async_rc(msg);
+out_success:
        if (rc == OPAL_SUCCESS) {
                rc = 0;
                if (retlen)
@@ -106,6 +109,8 @@ static int powernv_flash_async_op(struct mtd_info *mtd, 
enum flash_op op,
                rc = -EIO;
        }
 
+out:
+       opal_async_release_token(token);
        return rc;
 }
 
-- 
2.15.0