slimbus: messaging: start transaction ids from 1 instead of zero

[ Upstream commit 9659281ce78de0f15a4aa124da8f7450b1399c09 ]

As tid is unsigned its hard to figure out if the tid is valid or
invalid. So Start the transaction ids from 1 instead of zero
so that we could differentiate between a valid tid and invalid tids

This is useful in cases where controller would add a tid for controller
specific transfers.

Fixes: d3062a210930 ("slimbus: messaging: add slim_alloc/free_txn_tid()")
Cc: <stable@vger.kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20210809082428.11236-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/slimbus/messaging.c b/drivers/slimbus/messaging.c
index d5879142dbef1c4903f0e7279c46cf2859af80ea..3b77713f1e3fbb9f86454a295da7f6e611c1ddd9 100644 (file)
--- a/drivers/slimbus/messaging.c
+++ b/drivers/slimbus/messaging.c
@@ -66,7 +66,7 @@ int slim_alloc_txn_tid(struct slim_controller *ctrl, struct slim_msg_txn *txn)
        int ret = 0;
 
        spin_lock_irqsave(&ctrl->txn_lock, flags);
-       ret = idr_alloc_cyclic(&ctrl->tid_idr, txn, 0,
+       ret = idr_alloc_cyclic(&ctrl->tid_idr, txn, 1,
                                SLIM_MAX_TIDS, GFP_ATOMIC);
        if (ret < 0) {
                spin_unlock_irqrestore(&ctrl->txn_lock, flags);