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dma: mv_xor: use request_irq() instead of devm_request_irq()

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Even through the usage of devm_*() functions is generally recommended
over their classic variants, in the case of devm_request_irq()
combined with irq_of_parse_and_map(), it doesn't work nicely.

We have the following scenario:

 irq_of_parse_and_map(...)
 devm_request_irq(...)

For some reason, the driver initialization fails at a later
point. Since irq_of_parse_and_map() is no device-managed, we do a:

 irq_dispose_mapping(...)

Unfortunately, this doesn't work, because the free_irq() must be done
prior to calling irq_dispose_mapping(). But with the devm mechanism,
the automatic free_irq() would happen only after we get out of the
->probe() function.

So basically, we revert to using request_irq() with traditional error
handling, so that in case of error, free_irq() gets called before
irq_dispose_mapping().

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
This commit is contained in:
Thomas Petazzoni 2012-11-22 18:19:09 +01:00
parent c4b4b732b2
commit 2d0a074517
1 changed files with 6 additions and 5 deletions
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11
drivers/dma/mv_xor.c
View File

@ -1162,9 +1162,8 @@ mv_xor_channel_add(struct mv_xor_device *xordev,
/* clear errors before enabling interrupts */
mv_xor_device_clear_err_status(mv_chan);
ret = devm_request_irq(&pdev->dev, mv_chan->irq,
mv_xor_interrupt_handler,
0, dev_name(&pdev->dev), mv_chan);
ret = request_irq(mv_chan->irq, mv_xor_interrupt_handler,
0, dev_name(&pdev->dev), mv_chan);
if (ret)
goto err_free_dma;
@ -1185,14 +1184,14 @@ mv_xor_channel_add(struct mv_xor_device *xordev,
ret = mv_xor_memcpy_self_test(mv_chan);
dev_dbg(&pdev->dev, "memcpy self test returned %d\n", ret);
if (ret)
goto err_free_dma;
goto err_free_irq;
}
if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
ret = mv_xor_xor_self_test(mv_chan);
dev_dbg(&pdev->dev, "xor self test returned %d\n", ret);
if (ret)
goto err_free_dma;
goto err_free_irq;
}
dev_info(&pdev->dev, "Marvell XOR: "
@ -1205,6 +1204,8 @@ mv_xor_channel_add(struct mv_xor_device *xordev,
dma_async_device_register(dma_dev);
return mv_chan;
err_free_irq:
free_irq(mv_chan->irq, mv_chan);
err_free_dma:
dma_free_coherent(&pdev->dev, MV_XOR_POOL_SIZE,
mv_chan->dma_desc_pool_virt, mv_chan->dma_desc_pool);