[PATCH v28] dmaengine: qcom: bam_dma: free interrupt before the clock in error path

[Bartosz Golaszewski]

The BAM interrupt is requested with a devres helper and so on error it's
freed after probe() returns. We disable the clock before freeing or
masking it so it may still fire and we may end up reading BAM registers
with clock disabled.

Stop using devres for interrupts as we free it in remove() manually
anyway. Add an appropriate label and free the interrupt before disabling
the clock in error path and in remove().

Cc: stable@xxxxxxxxxxxxxxx
Fixes: e7c0fe2a5c84 ("dmaengine: add Qualcomm BAM dma driver")
Reported-by: Sashiko <sashiko-bot@xxxxxxxxxx>
Closes: https://sashiko.dev/#/patchset/20260427-qcom-qce-cmd-descr-v16-0-945fd1cafbbc%40oss.qualcomm.com?part=2
Reviewed-by: Manivannan Sadhasivam <mani@xxxxxxxxxx>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxxxxxxxx>
---
Sorry for the noise with v27, I didn't notice the change in dma/next.

This used to be part of the larger BAM DMA pipe locking series and never
got picked up despite months on the list. I'm resending it separately.
---
Changes in v28:
- Revert to using IRQF_TRIGGER_NONE when requesting the irq
- Link to v27: https://patch.msgid.link/20261008-bam-dma-free-irq-v27-1-660e70223e3c@xxxxxxxxxxxxxxxx

Changes in v27:
- Rabase on top of current dma/next
- Link to v26: https://patch.msgid.link/20261006-bam-dma-free-irq-v26-1-eef5c713d831@xxxxxxxxxxxxxxxx

Changes in v26:
- Rebased on top of current linux-next to address conflicts
- Link to v25: https://patch.msgid.link/20261002-bam-dma-free-irq-v25-1-f39e01d19910@xxxxxxxxxxxxxxxx

Changes in v25:
- Don't touch remove(), it's not wrong in its current version
- Link to v24: https://patch.msgid.link/20260723-qcom-qce-cmd-descr-v24-0-4f87bb4d9938@xxxxxxxxxxxxxxxx
---
 drivers/dma/qcom/bam_dma.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index 94cb957d4b187704e207361d629fde00e3e090bf..f67a93a37d48cc23dcef04fb434d2613a1f22a77 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -1332,8 +1332,8 @@ static int bam_dma_probe(struct platform_device *pdev)
 	for (i = 0; i < bdev->num_channels; i++)
 		bam_channel_init(bdev, &bdev->channels[i], i);
 
-	ret = devm_request_irq(bdev->dev, bdev->irq, bam_dma_irq,
-			IRQF_TRIGGER_NONE, "bam_dma", bdev);
+	ret = request_irq(bdev->irq, bam_dma_irq, IRQF_TRIGGER_NONE,
+			  "bam_dma", bdev);
 	if (ret)
 		goto err_bam_channel_exit;
 
@@ -1366,7 +1366,7 @@ static int bam_dma_probe(struct platform_device *pdev)
 	ret = dma_async_device_register(&bdev->common);
 	if (ret) {
 		dev_err(bdev->dev, "failed to register dma async device\n");
-		goto err_bam_channel_exit;
+		goto err_free_irq;
 	}
 
 	ret = of_dma_controller_register(pdev->dev.of_node, bam_dma_xlate,
@@ -1385,6 +1385,8 @@ static int bam_dma_probe(struct platform_device *pdev)
 
 err_unregister_dma:
 	dma_async_device_unregister(&bdev->common);
+err_free_irq:
+	free_irq(bdev->irq, bdev);
 err_bam_channel_exit:
 	for (i = 0; i < bdev->num_channels; i++)
 		tasklet_kill(&bdev->channels[i].vc.task);
@@ -1410,7 +1412,7 @@ static void bam_dma_remove(struct platform_device *pdev)
 	/* mask all interrupts for this execution environment */
 	writel_relaxed(0, bam_addr(bdev, 0,  BAM_IRQ_SRCS_MSK_EE));
 
-	devm_free_irq(bdev->dev, bdev->irq, bdev);
+	free_irq(bdev->irq, bdev);
 
 	for (i = 0; i < bdev->num_channels; i++) {
 		bam_dma_terminate_all(&bdev->channels[i].vc.chan);

---
base-commit: 53b32375c9caf793ff392f762236c90f2a062ae5
change-id: 20261002-bam-dma-free-irq-cac4b268c465

Best regards,
-- 
Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxxxxxxxx>