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dmaengine: tegra-apb: Error out if DMA_PREP_INTERRUPT flag is unset

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Apparently driver was never tested with DMA_PREP_INTERRUPT flag being
unset since it completely disables interrupt handling instead of skipping
the callbacks invocations, hence putting channel into unusable state.

The flag is always set by all of kernel drivers that use APB DMA, so let's
error out in otherwise case for consistency. It won't be difficult to
support that case properly if ever will be needed.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Dmitry Osipenko 2019-05-30 00:43:55 +03:00 committed by Vinod Koul
parent c983d805a7
commit dc161064be
1 changed files with 10 additions and 2 deletions
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12
drivers/dma/tegra20-apb-dma.c
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@ -988,8 +988,12 @@ static struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg(
csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
}
if (flags & DMA_PREP_INTERRUPT)
if (flags & DMA_PREP_INTERRUPT) {
csr |= TEGRA_APBDMA_CSR_IE_EOC;
} else {
WARN_ON_ONCE(1);
return NULL;
}
apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;
@ -1131,8 +1135,12 @@ static struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic(
csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
}
if (flags & DMA_PREP_INTERRUPT)
if (flags & DMA_PREP_INTERRUPT) {
csr |= TEGRA_APBDMA_CSR_IE_EOC;
} else {
WARN_ON_ONCE(1);
return NULL;
}
apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1;