From 7cb819c856d9668f6146ba3caa46d54efb17d9e9 Mon Sep 17 00:00:00 2001 From: Pierre-Yves MORDRET Date: Mon, 27 Jan 2020 09:53:29 +0100 Subject: dmaengine: stm32-mdma: add suspend/resume power management support Add suspend/resume power management relying on PM Runtime engine. Signed-off-by: Pierre-Yves MORDRET Signed-off-by: Amelie Delaunay Link: https://lore.kernel.org/r/20200127085334.13163-2-amelie.delaunay@st.com Signed-off-by: Vinod Koul --- drivers/dma/stm32-mdma.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'drivers/dma/stm32-mdma.c') diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c index 5838311cf990..2898411941d5 100644 --- a/drivers/dma/stm32-mdma.c +++ b/drivers/dma/stm32-mdma.c @@ -1697,7 +1697,40 @@ static int stm32_mdma_runtime_resume(struct device *dev) } #endif +#ifdef CONFIG_PM_SLEEP +static int stm32_mdma_pm_suspend(struct device *dev) +{ + struct stm32_mdma_device *dmadev = dev_get_drvdata(dev); + u32 ccr, id; + int ret; + + ret = pm_runtime_get_sync(dev); + if (ret < 0) + return ret; + + for (id = 0; id < dmadev->nr_channels; id++) { + ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(id)); + if (ccr & STM32_MDMA_CCR_EN) { + dev_warn(dev, "Suspend is prevented by Chan %i\n", id); + return -EBUSY; + } + } + + pm_runtime_put_sync(dev); + + pm_runtime_force_suspend(dev); + + return 0; +} + +static int stm32_mdma_pm_resume(struct device *dev) +{ + return pm_runtime_force_resume(dev); +} +#endif + static const struct dev_pm_ops stm32_mdma_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(stm32_mdma_pm_suspend, stm32_mdma_pm_resume) SET_RUNTIME_PM_OPS(stm32_mdma_runtime_suspend, stm32_mdma_runtime_resume, NULL) }; -- cgit v1.2.3