[PATCH v2 4/5] spi: microchip-core-qspi: Add lock context annotations

[Joseph CT Chan <jctchan@gmail.com>]

From: Bart Van Assche <bvanassche@acm.org>

Annotate mchp_coreqspi_prepare_message() with __cond_acquires() and
mchp_coreqspi_unprepare_message() with __releases() for op_lock in
drivers/spi/spi-microchip-core-qspi.c. Document message-scoped ownership
of op_lock across SPI core message preparation callbacks and enable
static context analysis to verify error-path unlocking.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Joseph CT Chan <josephctchan@google.com>
---
 drivers/spi/spi-microchip-core-qspi.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/spi/spi-microchip-core-qspi.c b/drivers/spi/spi-microchip-core-qspi.c
index c0ea65014d2e..a3143d966538 100644
--- a/drivers/spi/spi-microchip-core-qspi.c
+++ b/drivers/spi/spi-microchip-core-qspi.c
@@ -603,7 +603,10 @@ static const struct spi_controller_mem_caps mchp_coreqspi_mem_caps = {
 	.per_op_freq = true,
 };
 
+#define TO_MCHP_COREQSPI(ctlr) ((struct mchp_coreqspi *)spi_controller_get_devdata(ctlr))
+
 static int mchp_coreqspi_unprepare_message(struct spi_controller *ctlr, struct spi_message *m)
+	__releases(&TO_MCHP_COREQSPI(ctlr)->op_lock)
 {
 	struct mchp_coreqspi *qspi = spi_controller_get_devdata(ctlr);
 
@@ -619,6 +622,7 @@ static int mchp_coreqspi_unprepare_message(struct spi_controller *ctlr, struct s
 }
 
 static int mchp_coreqspi_prepare_message(struct spi_controller *ctlr, struct spi_message *m)
+	__cond_acquires(0, &TO_MCHP_COREQSPI(ctlr)->op_lock)
 {
 	struct mchp_coreqspi *qspi = spi_controller_get_devdata(ctlr);
 	struct spi_transfer *t = NULL;
@@ -685,6 +689,8 @@ static int mchp_coreqspi_prepare_message(struct spi_controller *ctlr, struct spi
 	return 0;
 };
 
+#undef TO_MCHP_COREQSPI
+
 static int mchp_coreqspi_transfer_one(struct spi_controller *ctlr, struct spi_device *spi,
 				      struct spi_transfer *t)
 {
-- 
2.56.0.385.gac671c819a-goog