firmware: arm_scmi: Perform earlier cinfo lookup call in do_xfer

Lookup cinfo data early in do_xfer so as to avoid any further init work
on xfer structure in case of error.

No functional change.

Link: https://lore.kernel.org/r/20211129191156.29322-2-cristian.marussi@arm.com
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 768926a..3cf161f 100644 (file)
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -766,6 +766,10 @@ static int do_xfer(const struct scmi_protocol_handle *ph,
                return -EINVAL;
        }
 
+       cinfo = idr_find(&info->tx_idr, pi->proto->id);
+       if (unlikely(!cinfo))
+               return -EINVAL;
+
        /*
         * Initialise protocol id now from protocol handle to avoid it being
         * overridden by mistake (or malice) by the protocol code mangling with
@@ -774,10 +778,6 @@ static int do_xfer(const struct scmi_protocol_handle *ph,
        xfer->hdr.protocol_id = pi->proto->id;
        reinit_completion(&xfer->done);
 
-       cinfo = idr_find(&info->tx_idr, xfer->hdr.protocol_id);
-       if (unlikely(!cinfo))
-               return -EINVAL;
-
        trace_scmi_xfer_begin(xfer->transfer_id, xfer->hdr.id,
                              xfer->hdr.protocol_id, xfer->hdr.seq,
                              xfer->hdr.poll_completion);