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| author | Pierre-Yves MORDRET <pierre-yves.mordret@st.com> | 2020-01-28 10:41:55 +0100 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2020-02-24 22:22:43 +0530 |
| commit | f65c2e14b096736585aa04cb7a43d5d54d287ddd (patch) | |
| tree | 1cbbffc5ba946d2d009590ce8b92d34c94ed15e4 /drivers/dma/stm32-dmamux.c | |
| parent | dfc708812a2acfc0ca56f56233b3c3e7b0d4ffe7 (diff) | |
| download | linux-f65c2e14b096736585aa04cb7a43d5d54d287ddd.tar.gz | |
dmaengine: stm32-dmamux: add suspend/resume power management support
Add suspend/resume power management relying on PM Runtime engine. Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> Link: https://lore.kernel.org/r/20200128094158.20361-2-amelie.delaunay@st.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma/stm32-dmamux.c')
| -rw-r--r-- | drivers/dma/stm32-dmamux.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/drivers/dma/stm32-dmamux.c b/drivers/dma/stm32-dmamux.c index 3c89bd39e096..08d2395c8943 100644 --- a/drivers/dma/stm32-dmamux.c +++ b/drivers/dma/stm32-dmamux.c @@ -41,6 +41,9 @@ struct stm32_dmamux_data { u32 dmamux_requests; /* Number of DMA requests routed toward DMAs */ spinlock_t lock; /* Protects register access */ unsigned long *dma_inuse; /* Used DMA channel */ + u32 ccr[STM32_DMAMUX_MAX_DMA_REQUESTS]; /* Used to backup CCR register + * in suspend + */ u32 dma_reqs[]; /* Number of DMA Request per DMA masters. * [0] holds number of DMA Masters. * To be kept at very end end of this structure @@ -318,7 +321,54 @@ static int stm32_dmamux_runtime_resume(struct device *dev) } #endif +#ifdef CONFIG_PM_SLEEP +static int stm32_dmamux_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct stm32_dmamux_data *stm32_dmamux = platform_get_drvdata(pdev); + int i, ret; + + ret = pm_runtime_get_sync(dev); + if (ret < 0) + return ret; + + for (i = 0; i < stm32_dmamux->dma_requests; i++) + stm32_dmamux->ccr[i] = stm32_dmamux_read(stm32_dmamux->iomem, + STM32_DMAMUX_CCR(i)); + + pm_runtime_put_sync(dev); + + pm_runtime_force_suspend(dev); + + return 0; +} + +static int stm32_dmamux_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct stm32_dmamux_data *stm32_dmamux = platform_get_drvdata(pdev); + int i, ret; + + ret = pm_runtime_force_resume(dev); + if (ret < 0) + return ret; + + ret = pm_runtime_get_sync(dev); + if (ret < 0) + return ret; + + for (i = 0; i < stm32_dmamux->dma_requests; i++) + stm32_dmamux_write(stm32_dmamux->iomem, STM32_DMAMUX_CCR(i), + stm32_dmamux->ccr[i]); + + pm_runtime_put_sync(dev); + + return 0; +} +#endif + static const struct dev_pm_ops stm32_dmamux_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(stm32_dmamux_suspend, stm32_dmamux_resume) SET_RUNTIME_PM_OPS(stm32_dmamux_runtime_suspend, stm32_dmamux_runtime_resume, NULL) }; |