dmaengine: dw-axi-dmac: report per-channel max_burst via device_caps#7011
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pelwell merged 1 commit intoraspberrypi:rpi-6.12.yfrom Aug 22, 2025
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To be discussed: Keep |
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Apart from the checkpatch indentation complaints, this looks good.
Don't we drop the assignment completely now we have the |
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Probably can do, yes. The array should be populated for all channels, so the fallback isn't really needed. I will amend my commit when I take care of checkpatch. |
The patch "dmaengine: dw-axi-dmac: add per-channel AXI burst length
support" programs ARLEN/AWLEN from the snps,axi-max-burst-len array but
still exposed a single max_burst value via dma_get_slave_caps(). As a
result all channels reported 8 even when limited to 4, leading to
warnings:
dma dma2chan5: requested source burst length 8 exceeds supported 4
Add a .device_caps callback to return the correct per-channel max_burst.
This allows drivers like amba-pl011 to clamp burst lengths properly.
Fixes: 0e4e6a0c4f4e ("dmaengine: dw-axi-dmac: add per-channel AXI burst length support")
Signed-off-by: Nicolai Buchwitz <nb@tipi-net.de>
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Thanks! |
popcornmix
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kernel: dmaengine: dw-axi-dmac: report per-channel max_burst via device_caps See: raspberrypi/linux#7011 kernel: Update tpm-slb9673-overlay.dts See: raspberrypi/linux#6993 kernel: Enable Full Screen Splash Images See: raspberrypi/linux#7005 kernel: overlays: Rebuild 5inch display from the 7inch See: raspberrypi/linux#7016
popcornmix
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kernel: dmaengine: dw-axi-dmac: report per-channel max_burst via device_caps See: raspberrypi/linux#7011 kernel: Update tpm-slb9673-overlay.dts See: raspberrypi/linux#6993 kernel: Enable Full Screen Splash Images See: raspberrypi/linux#7005 kernel: overlays: Rebuild 5inch display from the 7inch See: raspberrypi/linux#7016
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The patch "dmaengine: dw-axi-dmac: add per-channel AXI burst length support" programs ARLEN/AWLEN from the snps,axi-max-burst-len array but still exposed a single max_burst value via dma_get_slave_caps(). As a result all channels reported 8 even when limited to 4, leading to warnings:
dma dma2chan5: requested source burst length 8 exceeds supported 4
Add a .device_caps callback to return the correct per-channel max_burst. This allows drivers like amba-pl011 to clamp burst lengths properly.
Fixes: 0e4e6a0c4f4e ("dmaengine: dw-axi-dmac: add per-channel AXI burst length support") #6994