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* next take at setting up a dma mask by default for platform devices
@ 2019-08-11  8:05 Christoph Hellwig
  2019-08-11  8:05 ` [PATCH 1/6] usb: don't create dma pools for HCDs with a localmem_pool Christoph Hellwig
                   ` (6 more replies)
  0 siblings, 7 replies; 19+ messages in thread
From: Christoph Hellwig @ 2019-08-11  8:05 UTC (permalink / raw)
  To: Greg Kroah-Hartman, Maxime Chevallier
  Cc: Gavin Li, Laurentiu Tudor, Minas Harutyunyan, Alan Stern,
	Geoff Levand, Michal Simek, Shawn Guo, Sascha Hauer,
	Pengutronix Kernel Team, Fabio Estevam, NXP Linux Team,
	Olav Kongas, Tony Prisk, Mathias Nyman, Bin Liu,
	linux-arm-kernel, linux-usb, linuxppc-dev, iommu, linux-arch,
	linux-kernel

Hi all,

this is another attempt to make sure the dma_mask pointer is always
initialized for platform devices.  Not doing so lead to lots of
boilerplate code, and makes platform devices different from all our
major busses like PCI where we always set up a dma_mask.  In the long
run this should also help to eventually make dma_mask a scalar value
instead of a pointer and remove even more cruft.

The bigger blocker for this last time was the fact that the usb
subsystem uses the presence or lack of a dma_mask to check if the core
should do dma mapping for the driver, which is highly unusual.  So we
fix this first.  Note that this has some overlap with the pending
desire to use the proper dma_mmap_coherent helper for mapping usb
buffers.  The first two patches from this series should probably
go into 5.3 and then uses as the basis for the decision to use
dma_mmap_coherent.

^ permalink raw reply	[flat|nested] 19+ messages in thread
* next take at setting up a dma mask by default for platform devices v2
@ 2019-08-16  6:24 Christoph Hellwig
  2019-08-16  6:24 ` [PATCH 6/6] driver core: initialize a default DMA mask for platform device Christoph Hellwig
  0 siblings, 1 reply; 19+ messages in thread
From: Christoph Hellwig @ 2019-08-16  6:24 UTC (permalink / raw)
  To: Greg Kroah-Hartman, Maxime Chevallier
  Cc: Gavin Li, Laurentiu Tudor, Minas Harutyunyan, Alan Stern,
	Geoff Levand, Michal Simek, Shawn Guo, Sascha Hauer,
	Pengutronix Kernel Team, Fabio Estevam, NXP Linux Team,
	Mathias Nyman, Bin Liu, linux-arm-kernel, linux-usb,
	linuxppc-dev, linux-m68k, iommu, linux-arch, linux-kernel

Hi all,

this is another attempt to make sure the dma_mask pointer is always
initialized for platform devices.  Not doing so lead to lots of
boilerplate code, and makes platform devices different from all our
major busses like PCI where we always set up a dma_mask.  In the long
run this should also help to eventually make dma_mask a scalar value
instead of a pointer and remove even more cruft.

The bigger blocker for this last time was the fact that the usb
subsystem uses the presence or lack of a dma_mask to check if the core
should do dma mapping for the driver, which is highly unusual.  So we
fix this first.  Note that this has some overlap with the pending
desire to use the proper dma_mmap_coherent helper for mapping usb
buffers.  The first two patches have already been queued up by Greg
and are only included for completeness.

Changes since v1:
 - fix a compile error in the ppc of ohci driver
 - revamp the last patch to get rid of the archdata callout entirely.

^ permalink raw reply	[flat|nested] 19+ messages in thread

end of thread, back to index

Thread overview: 19+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-08-11  8:05 next take at setting up a dma mask by default for platform devices Christoph Hellwig
2019-08-11  8:05 ` [PATCH 1/6] usb: don't create dma pools for HCDs with a localmem_pool Christoph Hellwig
2019-08-11  8:05 ` [PATCH 2/6] usb: add a hcd_uses_dma helper Christoph Hellwig
2019-08-11  8:05 ` [PATCH 3/6] usb: add a HCD_DMA flag instead of guestimating DMA capabilities Christoph Hellwig
2019-08-12 11:57   ` Christoph Hellwig
2019-08-11  8:05 ` [PATCH 4/6] usb/max3421: remove the dummy {un,}map_urb_for_dma methods Christoph Hellwig
2019-08-11  8:05 ` [PATCH 5/6] dma-mapping: remove is_device_dma_capable Christoph Hellwig
2019-08-11  8:05 ` [PATCH 6/6] driver core: initialize a default DMA mask for platform device Christoph Hellwig
2019-08-14 15:49   ` Robin Murphy
2019-08-15 13:32     ` Christoph Hellwig
2019-08-15 13:03   ` Greg Kroah-Hartman
2019-08-15 13:38     ` Christoph Hellwig
2019-08-15 14:05       ` Greg Kroah-Hartman
2019-08-15 13:23 ` next take at setting up a dma mask by default for platform devices Greg Kroah-Hartman
2019-08-15 13:25   ` Christoph Hellwig
2019-08-15 14:05     ` Greg Kroah-Hartman
2019-08-15 14:39     ` Alan Stern
2019-08-16  6:24 next take at setting up a dma mask by default for platform devices v2 Christoph Hellwig
2019-08-16  6:24 ` [PATCH 6/6] driver core: initialize a default DMA mask for platform device Christoph Hellwig
2019-08-16  7:39   ` Geert Uytterhoeven

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