diff options
author | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2010-08-16 18:42:58 +0100 |
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committer | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2010-08-16 18:42:58 +0100 |
commit | e4862f2f6f5653dfb67f3ba2b6f0bc74516ed51a (patch) | |
tree | 1db5a0540a4eecfad9b7daee476b985e82ddc810 /include/linux/dmaengine.h | |
parent | ec62dbd7eb8e3dddb221da89ecbcea0fc3dee8c1 (diff) | |
parent | b2c1e07b81a126e5846dfc3d36f559d861df59f4 (diff) |
Merge branch 'for-2.6.36' into for-2.6.37
Fairly simple conflicts, the most serious ones are the i.MX ones which I
suspect now need another rename.
Conflicts:
arch/arm/mach-mx2/clock_imx27.c
arch/arm/mach-mx2/devices.c
arch/arm/mach-omap2/board-rx51-peripherals.c
arch/arm/mach-omap2/board-zoom2.c
sound/soc/fsl/mpc5200_dma.c
sound/soc/fsl/mpc5200_dma.h
sound/soc/fsl/mpc8610_hpcd.c
sound/soc/pxa/spitz.c
Diffstat (limited to 'include/linux/dmaengine.h')
-rw-r--r-- | include/linux/dmaengine.h | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 5204f018931..c61d4ca27bc 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -114,11 +114,17 @@ enum dma_ctrl_flags { * @DMA_TERMINATE_ALL: terminate all ongoing transfers * @DMA_PAUSE: pause ongoing transfers * @DMA_RESUME: resume paused transfer + * @DMA_SLAVE_CONFIG: this command is only implemented by DMA controllers + * that need to runtime reconfigure the slave channels (as opposed to passing + * configuration data in statically from the platform). An additional + * argument of struct dma_slave_config must be passed in with this + * command. */ enum dma_ctrl_cmd { DMA_TERMINATE_ALL, DMA_PAUSE, DMA_RESUME, + DMA_SLAVE_CONFIG, }; /** @@ -199,6 +205,71 @@ struct dma_chan_dev { atomic_t *idr_ref; }; +/** + * enum dma_slave_buswidth - defines bus with of the DMA slave + * device, source or target buses + */ +enum dma_slave_buswidth { + DMA_SLAVE_BUSWIDTH_UNDEFINED = 0, + DMA_SLAVE_BUSWIDTH_1_BYTE = 1, + DMA_SLAVE_BUSWIDTH_2_BYTES = 2, + DMA_SLAVE_BUSWIDTH_4_BYTES = 4, + DMA_SLAVE_BUSWIDTH_8_BYTES = 8, +}; + +/** + * struct dma_slave_config - dma slave channel runtime config + * @direction: whether the data shall go in or out on this slave + * channel, right now. DMA_TO_DEVICE and DMA_FROM_DEVICE are + * legal values, DMA_BIDIRECTIONAL is not acceptable since we + * need to differentiate source and target addresses. + * @src_addr: this is the physical address where DMA slave data + * should be read (RX), if the source is memory this argument is + * ignored. + * @dst_addr: this is the physical address where DMA slave data + * should be written (TX), if the source is memory this argument + * is ignored. + * @src_addr_width: this is the width in bytes of the source (RX) + * register where DMA data shall be read. If the source + * is memory this may be ignored depending on architecture. + * Legal values: 1, 2, 4, 8. + * @dst_addr_width: same as src_addr_width but for destination + * target (TX) mutatis mutandis. + * @src_maxburst: the maximum number of words (note: words, as in + * units of the src_addr_width member, not bytes) that can be sent + * in one burst to the device. Typically something like half the + * FIFO depth on I/O peripherals so you don't overflow it. This + * may or may not be applicable on memory sources. + * @dst_maxburst: same as src_maxburst but for destination target + * mutatis mutandis. + * + * This struct is passed in as configuration data to a DMA engine + * in order to set up a certain channel for DMA transport at runtime. + * The DMA device/engine has to provide support for an additional + * command in the channel config interface, DMA_SLAVE_CONFIG + * and this struct will then be passed in as an argument to the + * DMA engine device_control() function. + * + * The rationale for adding configuration information to this struct + * is as follows: if it is likely that most DMA slave controllers in + * the world will support the configuration option, then make it + * generic. If not: if it is fixed so that it be sent in static from + * the platform data, then prefer to do that. Else, if it is neither + * fixed at runtime, nor generic enough (such as bus mastership on + * some CPU family and whatnot) then create a custom slave config + * struct and pass that, then make this config a member of that + * struct, if applicable. + */ +struct dma_slave_config { + enum dma_data_direction direction; + dma_addr_t src_addr; + dma_addr_t dst_addr; + enum dma_slave_buswidth src_addr_width; + enum dma_slave_buswidth dst_addr_width; + u32 src_maxburst; + u32 dst_maxburst; +}; + static inline const char *dma_chan_name(struct dma_chan *chan) { return dev_name(&chan->dev->device); |