arm: socfpga: mailbox: Always read mailbox responses before returning status

Mailbox driver should always check for the length of the response
and read the response data before returning the response status to
caller.

Signed-off-by: Chee Hong Ang <chee.hong.ang@intel.com>
Reviewed-by: Ley Foon Tan <ley.foon.tan@intel.com>

diff --git a/arch/arm/mach-socfpga/mailbox_s10.c b/arch/arm/mach-socfpga/mailbox_s10.c
index 729d9b04fa5f0be985a9e7c79b94c406201caa50..e8a587f00796d61fefb2905487af6e045d8da9b9 100644 (file)
--- a/arch/arm/mach-socfpga/mailbox_s10.c
+++ b/arch/arm/mach-socfpga/mailbox_s10.c
@@ -221,9 +221,7 @@ static __always_inline int mbox_send_cmd_common(u8 id, u32 cmd, u8 is_indirect,
                        if ((MBOX_RESP_CLIENT_GET(resp) ==
                             MBOX_CLIENT_ID_UBOOT) &&
                            (MBOX_RESP_ID_GET(resp) == id)) {
-                               ret = MBOX_RESP_ERR_GET(resp);
-                               if (ret)
-                                       return ret;
+                               int resp_err = MBOX_RESP_ERR_GET(resp);
 
                                if (resp_buf_len) {
                                        buf_len = *resp_buf_len;
@@ -252,7 +250,7 @@ static __always_inline int mbox_send_cmd_common(u8 id, u32 cmd, u8 is_indirect,
                                                buf_len--;
                                        }
                                }
-                               return ret;
+                               return resp_err;
                        }
                }
        };