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2022-02-08dma-buf-map: Rename to iosys-mapLucas De Marchi1-0/+9
Rename struct dma_buf_map to struct iosys_map and corresponding APIs. Over time dma-buf-map grew up to more functionality than the one used by dma-buf: in fact it's just a shim layer to abstract system memory, that can be accessed via regular load and store, from IO memory that needs to be acessed via arch helpers. The idea is to extend this API so it can fulfill other needs, internal to a single driver. Example: in the i915 driver it's desired to share the implementation for integrated graphics, which uses mostly system memory, with discrete graphics, which may need to access IO memory. The conversion was mostly done with the following semantic patch: @r1@ @@ - struct dma_buf_map + struct iosys_map @r2@ @@ ( - DMA_BUF_MAP_INIT_VADDR + IOSYS_MAP_INIT_VADDR | - dma_buf_map_set_vaddr + iosys_map_set_vaddr | - dma_buf_map_set_vaddr_iomem + iosys_map_set_vaddr_iomem | - dma_buf_map_is_equal + iosys_map_is_equal | - dma_buf_map_is_null + iosys_map_is_null | - dma_buf_map_is_set + iosys_map_is_set | - dma_buf_map_clear + iosys_map_clear | - dma_buf_map_memcpy_to + iosys_map_memcpy_to | - dma_buf_map_incr + iosys_map_incr ) @@ @@ - #include <linux/dma-buf-map.h> + #include <linux/iosys-map.h> Then some files had their includes adjusted and some comments were update to remove mentions to dma-buf-map. Since this is not specific to dma-buf anymore, move the documentation to the "Bus-Independent Device Accesses" section. v2: - Squash patches v3: - Fix wrong removal of dma-buf.h from MAINTAINERS - Move documentation from dma-buf.rst to device-io.rst v4: - Change documentation title and level Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> Acked-by: Christian König <christian.koenig@amd.com> Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patchwork.freedesktop.org/patch/msgid/20220204170541.829227-1-lucas.demarchi@intel.com
2021-04-08docs: driver-api: device-io: Document ioremap() variants & access funcsHector Martin1-0/+218
This documents the newly introduced ioremap_np() along with all the other common ioremap() variants, and some higher-level abstractions available. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Hector Martin <marcan@marcan.st>
2021-04-08docs: driver-api: device-io: Document I/O access functionsArnd Bergmann1-0/+138
This adds more detailed descriptions of the various read/write primitives available for use with I/O memory/ports. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Hector Martin <marcan@marcan.st>
2020-07-13Driver-API: Documentation: Replace deprecated :c:func: UsagePuranjay Mohan1-11/+11
Replace :c:func: with func() as the previous usage is deprecated. Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> Link: https://lore.kernel.org/r/20200707053252.32703-1-puranjay12@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-04-08Documentation: Kill all references to mmiowb()Will Deacon1-45/+0
The guarantees provided by mmiowb() are now provided implicitly by spin_unlock(), so remove all references to this most confusing of barriers from our Documentation. Good riddance. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-02-01docs: Convert the deviceio template to RSTJonathan Corbet1-0/+201
Convert deviceiobook.tmpl to RST and incorporate it into the driver API manual. Like the rest of our documentation, this one could use some work. There's no mention of ioremap() and friends, no mention of io_read*() and friends. But we have nice documentation for all those folks writing new drivers that do port I/O :). The :c:func: notation has been left off of all the read*/write* functions. There's no kerneldoc comments for them anyway, so those links will never be live, and writing a bunch of repetitive "read a byte from I/O memory" comments lacks appeal. Cc: Matthew Wilcox <willy@infradead.org> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Signed-off-by: Jonathan Corbet <corbet@lwn.net>