Hello,
This patchset changes the way the runtime PM is implemented in the PL330 DMA engine driver. The main goal of such change is to add support for the audio power domain to Exynos5 SoCs (5250, 542x, 5433, probably others) and let it to be properly turned off, when no audio is being used. Switching to non-irq-safe runtime PM is required to properly let power domain to be turned off (irq-safe runtime PM keeps power domain turned on all the time) and to integrate with clock controller's runtime PM (this cannot be workarounded any other way, PL330 uses clocks from the controller, which belongs to the same power domain).
For more details of the proposed change to the PL330 driver see patch #4.
Audio power domain on Exynos5 SoCs contains following hardware modules: 1. clock controller 2. pin controller 3. PL330 DMA controller 4. I2S audio controller
Patches for adding or fixing runtime PM for each of the above devices is handled separately.
Runtime PM patches for clock controllers is possible and has been proposed in the following thread (pending review): "[PATCH v4 0/4] Add runtime PM support for clocks (on Exynos SoC example)", http://www.spinics.net/lists/arm-kernel/msg550747.html
Runtime PM support for Exynos pin controller has been posted in the following thread: "[PATCH 0/9] Runtime PM for Exynos pin controller driver", http://www.spinics.net/lists/arm-kernel/msg550161.html
Exynos I2S driver supports runtime PM, but some fixes were needed for it and they are already queued to linux-next.
This patchset is based on linux-next from 25th January 2017 with "dmaengine: pl330: fix double lock" patch applied.
Best regards Marek Szyprowski Samsung R&D Institute Poland
Changelog:
v7: - added missing of_dma_request_slave_channel API change to sound/soc/sh/rcar driver - extended commit message with information about drawbacks of irq-safe runtime pm - added Ulf's reviewed-by tags
v6: https://www.spinics.net/lists/arm-kernel/msg557377.html - fixed pl330 system sleep suspend/resume callbacks, previous implementation incorrectly tried to unprepare clocks unconditionally - after a fix pl330 suspend/resume callbacks can be simply replaced by generic pm_runtime_force_{suspend,resume} helpers, what simplifies code even more
v5: https://www.spinics.net/lists/arm-kernel/msg555001.html - added Acks - additional mutex is indeed not needed, rely on dma_list_mutex in dmaengine core, added comment about locking
v4: http://www.spinics.net/lists/dmaengine/msg12329.html - rebased onto "dmaengine: pl330: fix double lock" patch: http://www.spinics.net/lists/dmaengine/msg12289.html - added a mutex to protect runtime PM links creation/removal to avoid races - moved mem2mem channel case handing to pl330_{add,del}_slave_pm_link functions to simplify code and error paths
v3: http://www.spinics.net/lists/dmaengine/msg12245.html - removed pl330_filter function as suggested by Arnd Bergmann - removed pl330.h from arch/arm/plat-samsung/devs.c - fixes some minor style issues pointed by Krzysztof Kozlowski
v2: https://www.spinics.net/lists/arm-kernel/msg552772.html - rebased onto linux next-20170109 - improved patch description - separated patch #3 from #4 (storing a pointer to slave device for each DMA channel) as requested by Krzysztof Kozlowski
v1: https://www.spinics.net/lists/arm-kernel/msg550008.html - initial version
Patch summary:
Marek Szyprowski (4): dmaengine: pl330: remove pdata based initialization dmaengine: Forward slave device pointer to of_xlate callback dmaengine: pl330: Store pointer to slave device dmaengine: pl330: Don't require irq-safe runtime PM
arch/arm/plat-samsung/devs.c | 1 - drivers/dma/amba-pl08x.c | 2 +- drivers/dma/at_hdmac.c | 4 +- drivers/dma/at_xdmac.c | 2 +- drivers/dma/bcm2835-dma.c | 2 +- drivers/dma/coh901318.c | 2 +- drivers/dma/cppi41.c | 2 +- drivers/dma/dma-jz4780.c | 2 +- drivers/dma/dmaengine.c | 2 +- drivers/dma/dw/platform.c | 2 +- drivers/dma/edma.c | 4 +- drivers/dma/fsl-edma.c | 2 +- drivers/dma/img-mdc-dma.c | 2 +- drivers/dma/imx-dma.c | 2 +- drivers/dma/imx-sdma.c | 2 +- drivers/dma/k3dma.c | 2 +- drivers/dma/lpc18xx-dmamux.c | 2 +- drivers/dma/mmp_pdma.c | 2 +- drivers/dma/mmp_tdma.c | 2 +- drivers/dma/moxart-dma.c | 2 +- drivers/dma/mxs-dma.c | 2 +- drivers/dma/nbpfaxi.c | 2 +- drivers/dma/of-dma.c | 19 ++-- drivers/dma/pl330.c | 220 ++++++++++++++++------------------------ drivers/dma/pxa_dma.c | 2 +- drivers/dma/qcom/bam_dma.c | 2 +- drivers/dma/sh/rcar-dmac.c | 2 +- drivers/dma/sh/shdma-of.c | 2 +- drivers/dma/sh/usb-dmac.c | 2 +- drivers/dma/sirf-dma.c | 2 +- drivers/dma/st_fdma.c | 2 +- drivers/dma/ste_dma40.c | 2 +- drivers/dma/stm32-dma.c | 2 +- drivers/dma/sun4i-dma.c | 2 +- drivers/dma/sun6i-dma.c | 2 +- drivers/dma/tegra20-apb-dma.c | 2 +- drivers/dma/tegra210-adma.c | 2 +- drivers/dma/xilinx/xilinx_dma.c | 2 +- drivers/dma/xilinx/zynqmp_dma.c | 2 +- drivers/dma/zx_dma.c | 2 +- include/linux/amba/pl330.h | 35 ------- include/linux/of_dma.h | 19 ++-- sound/soc/sh/rcar/dma.c | 5 +- sound/soc/sh/rcar/dvc.c | 3 +- sound/soc/sh/rcar/rsnd.h | 3 +- sound/soc/sh/rcar/src.c | 3 +- sound/soc/sh/rcar/ssi.c | 3 +- 47 files changed, 158 insertions(+), 231 deletions(-) delete mode 100644 include/linux/amba/pl330.h