[PATCH] spi: tegra210-quad: Fix false positive WARN on interrupt timeout with transfer complete

[Breno Leitao]

The WARN_ON_ONCE/WARN_ON fired unconditionally on any completion
timeout, including the recoverable case where the interrupt was lost but
the hardware actually finished the transfer. This produced a noisy splat
with a full call trace even though the driver successfully recovered via
tegra_qspi_handle_timeout().

Since tegra210 uses threaded interrupts, the transfer completion can be
signaled before the interrupt fires, making this false positive case
common in practice.

Almost all the hosts I sysadmin in my fleet produce the following splat:

	WARNING: CPU: 47 PID: 844 at drivers/spi/spi-tegra210-quad.c:1226 tegra_qspi_transfer_one_message+0x8a4/0xba8
	....
	tegra-qspi NVDA1513:00: QSPI interrupt timeout, but transfer complete

Move WARN_ON_ONCE/WARN_ON to fire only on real unrecoverable timeouts,
i.e., when tegra_qspi_handle_timeout() confirms the hardware did NOT
complete. This makes the warning actionable instead of just polluting
the metrics.

Signed-off-by: Breno Leitao <leitao@xxxxxxxxxx>
---
 drivers/spi/spi-tegra210-quad.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-tegra210-quad.c b/drivers/spi/spi-tegra210-quad.c
index 7cca5578eba31..db28dd556484b 100644
--- a/drivers/spi/spi-tegra210-quad.c
+++ b/drivers/spi/spi-tegra210-quad.c
@@ -1223,7 +1223,7 @@ static int tegra_qspi_combined_seq_xfer(struct tegra_qspi *tqspi,
 					(&tqspi->xfer_completion,
 					QSPI_DMA_TIMEOUT);
 
-			if (WARN_ON_ONCE(ret == 0)) {
+			if (ret == 0) {
 				/*
 				 * Check if hardware completed the transfer
 				 * even though interrupt was lost or delayed.
@@ -1232,6 +1232,7 @@ static int tegra_qspi_combined_seq_xfer(struct tegra_qspi *tqspi,
 				ret = tegra_qspi_handle_timeout(tqspi);
 				if (ret < 0) {
 					/* Real timeout - clean up and fail */
+					WARN_ON_ONCE(1);
 					dev_err(tqspi->dev, "transfer timeout\n");
 
 					/* Abort transfer by resetting pio/dma bit */
@@ -1340,7 +1341,7 @@ static int tegra_qspi_non_combined_seq_xfer(struct tegra_qspi *tqspi,
 
 		ret = wait_for_completion_timeout(&tqspi->xfer_completion,
 						  QSPI_DMA_TIMEOUT);
-		if (WARN_ON(ret == 0)) {
+		if (ret == 0) {
 			/*
 			 * Check if hardware completed the transfer even though
 			 * interrupt was lost or delayed. If so, process the
@@ -1349,6 +1350,7 @@ static int tegra_qspi_non_combined_seq_xfer(struct tegra_qspi *tqspi,
 			ret = tegra_qspi_handle_timeout(tqspi);
 			if (ret < 0) {
 				/* Real timeout - clean up and fail */
+				WARN_ON(1);
 				dev_err(tqspi->dev, "transfer timeout\n");
 
 				if (tqspi->is_curr_dma_xfer)

---
base-commit: f3e6330d7fe42b204af05a2dbc68b379e0ad179e
change-id: 20260408-tegra_warn-cecd2ca3a61b

Best regards,
--  
Breno Leitao <leitao@xxxxxxxxxx>