[PATCH 01/10] dmaengine: pl08x: Defer OF DMA controller registration until slave setup

[Lee Jones <lee@kernel.org>]

pl08x_of_probe() registers the controller with
of_dma_controller_register() before pl08x_dma_init_virtual_channels()
initialises the slave channels list and before
dma_async_device_register() registers the slave DMA device, and
pl08x_probe() does not unregister the OF DMA controller if subsequent
initialisation fails.

Move of_dma_controller_register() after dma_async_device_register() for
the slave device and unwind slave device registration if OF controller
registration fails.

Fixes: aa4734da6674 ("dmaengine: pl08x: support dt channel assignment")
Closes: https://sashiko.dev/#/bug/linux-4e233fb9-3b0c-4442-b601-c6706c9f5aba
Cc: stable@vger.kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>
---
 drivers/dma/amba-pl08x.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index 543c2eb8cfa8..d8441e338502 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -2678,6 +2678,12 @@ static int pl08x_of_probe(struct amba_device *adev,
 
 	pl08x->pd = pd;
 
+	return 0;
+}
+
+static int pl08x_of_register(struct amba_device *adev,
+			     struct pl08x_driver_data *pl08x)
+{
 	return of_dma_controller_register(adev->dev.of_node, pl08x_of_xlate,
 					  pl08x);
 }
@@ -2688,6 +2694,12 @@ static inline int pl08x_of_probe(struct amba_device *adev,
 {
 	return -EINVAL;
 }
+
+static inline int pl08x_of_register(struct amba_device *adev,
+				    struct pl08x_driver_data *pl08x)
+{
+	return 0;
+}
 #endif
 
 static int pl08x_probe(struct amba_device *adev, const struct amba_id *id)
@@ -2944,6 +2956,15 @@ static int pl08x_probe(struct amba_device *adev, const struct amba_id *id)
 			__func__, ret);
 			goto out_no_slave_reg;
 		}
+		if (np) {
+			ret = pl08x_of_register(adev, pl08x);
+			if (ret) {
+				dev_warn(&pl08x->adev->dev,
+					 "%s failed to register OF DMA controller - %d\n",
+					 __func__, ret);
+				goto out_no_of_dma;
+			}
+		}
 	}
 
 	amba_set_drvdata(adev, pl08x);
@@ -2954,6 +2975,8 @@ static int pl08x_probe(struct amba_device *adev, const struct amba_id *id)
 
 	return 0;
 
+out_no_of_dma:
+	dma_async_device_unregister(&pl08x->slave);
 out_no_slave_reg:
 	dma_async_device_unregister(&pl08x->memcpy);
 out_no_memcpy_reg:
-- 
2.56.0.567.gdb80ae8cd5-goog