From: Srinivas Kandagatla srinivas.kandagatla@linaro.org
stable inclusion from linux-4.19.205 commit ac8d2c61359c3aca1f3f1c46f2fd3aca4fd4497e
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[ Upstream commit a263c1ff6abe0e66712f40d595bbddc7a35907f8 ]
In some usecases transaction ids are dynamically allocated inside the controller driver after sending the messages which have generic acknowledge responses. So check for this before refcounting pm_runtime.
Without this we would end up imbalancing runtime pm count by doing pm_runtime_put() in both slim_do_transfer() and slim_msg_response() for a single pm_runtime_get() in slim_do_transfer()
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/20210809082428.11236-3-srinivas.kandagatla@linaro.... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/slimbus/messaging.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/slimbus/messaging.c b/drivers/slimbus/messaging.c index 3b77713f1e3fb..ddf0371ad52b2 100644 --- a/drivers/slimbus/messaging.c +++ b/drivers/slimbus/messaging.c @@ -131,7 +131,8 @@ int slim_do_transfer(struct slim_controller *ctrl, struct slim_msg_txn *txn) goto slim_xfer_err; } } - + /* Initialize tid to invalid value */ + txn->tid = 0; need_tid = slim_tid_txn(txn->mt, txn->mc);
if (need_tid) { @@ -163,7 +164,7 @@ int slim_do_transfer(struct slim_controller *ctrl, struct slim_msg_txn *txn) txn->mt, txn->mc, txn->la, ret);
slim_xfer_err: - if (!clk_pause_msg && (!need_tid || ret == -ETIMEDOUT)) { + if (!clk_pause_msg && (txn->tid == 0 || ret == -ETIMEDOUT)) { /* * remove runtime-pm vote if this was TX only, or * if there was error during this transaction