This series brings improvements to the DMAMUX driver with support of power management and probe function gets a cleanup. Etienne Carriere (3): dmaengine: stm32-dmamux: fix clock handling in probe sequence dmaengine: stm32-dmamux: use reset controller only at probe time dmaengine: stm32-dmamux: driver defers probe for clock and reset Pierre-Yves MORDRET (1): dmaengine: stm32-dmamux: add suspend/resume power management support drivers/dma/stm32-dmamux.c | 93 +++++++++++++++++++++++++++++++------- 1 file changed, 77 insertions(+), 16 deletions(-) -- 2.17.1
From: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> 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> --- drivers/dma/stm32-dmamux.c | 50 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) 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) }; -- 2.17.1
From: Etienne Carriere <etienne.carriere@st.com> This change ensures the DMAMUX device is reset only once it is clocked and that clock is released in a safe state when probe operation fails. Signed-off-by: Etienne Carriere <etienne.carriere@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> --- drivers/dma/stm32-dmamux.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/drivers/dma/stm32-dmamux.c b/drivers/dma/stm32-dmamux.c index 08d2395c8943..a862d3339fb7 100644 --- a/drivers/dma/stm32-dmamux.c +++ b/drivers/dma/stm32-dmamux.c @@ -259,6 +259,12 @@ static int stm32_dmamux_probe(struct platform_device *pdev) return ret; } + ret = clk_prepare_enable(stm32_dmamux->clk); + if (ret < 0) { + dev_err(&pdev->dev, "clk_prep_enable error: %d\n", ret); + return ret; + } + stm32_dmamux->rst = devm_reset_control_get(&pdev->dev, NULL); if (!IS_ERR(stm32_dmamux->rst)) { reset_control_assert(stm32_dmamux->rst); @@ -274,14 +280,6 @@ static int stm32_dmamux_probe(struct platform_device *pdev) pm_runtime_set_active(&pdev->dev); pm_runtime_enable(&pdev->dev); - if (!IS_ERR(stm32_dmamux->clk)) { - ret = clk_prepare_enable(stm32_dmamux->clk); - if (ret < 0) { - dev_err(&pdev->dev, "clk_prep_enable error: %d\n", ret); - return ret; - } - } - pm_runtime_get_noresume(&pdev->dev); /* Reset the dmamux */ @@ -290,8 +288,12 @@ static int stm32_dmamux_probe(struct platform_device *pdev) pm_runtime_put(&pdev->dev); - return of_dma_router_register(node, stm32_dmamux_route_allocate, + ret = of_dma_router_register(node, stm32_dmamux_route_allocate, &stm32_dmamux->dmarouter); + if (ret) + clk_disable_unprepare(stm32_dmamux->clk); + + return ret; } #ifdef CONFIG_PM -- 2.17.1
From: Etienne Carriere <etienne.carriere@st.com> Remove reset controller reference from device instance since it is used only at probe time. Signed-off-by: Etienne Carriere <etienne.carriere@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> --- drivers/dma/stm32-dmamux.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/dma/stm32-dmamux.c b/drivers/dma/stm32-dmamux.c index a862d3339fb7..1dfecbac64cf 100644 --- a/drivers/dma/stm32-dmamux.c +++ b/drivers/dma/stm32-dmamux.c @@ -35,7 +35,6 @@ struct stm32_dmamux { struct stm32_dmamux_data { struct dma_router dmarouter; struct clk *clk; - struct reset_control *rst; void __iomem *iomem; u32 dma_requests; /* Number of DMA requests connected to DMAMUX */ u32 dmamux_requests; /* Number of DMA requests routed toward DMAs */ @@ -182,6 +181,7 @@ static int stm32_dmamux_probe(struct platform_device *pdev) struct stm32_dmamux_data *stm32_dmamux; struct resource *res; void __iomem *iomem; + struct reset_control *rst; int i, count, ret; u32 dma_req; @@ -265,11 +265,11 @@ static int stm32_dmamux_probe(struct platform_device *pdev) return ret; } - stm32_dmamux->rst = devm_reset_control_get(&pdev->dev, NULL); - if (!IS_ERR(stm32_dmamux->rst)) { - reset_control_assert(stm32_dmamux->rst); + rst = devm_reset_control_get(&pdev->dev, NULL); + if (!IS_ERR(rst)) { + reset_control_assert(rst); udelay(2); - reset_control_deassert(stm32_dmamux->rst); + reset_control_deassert(rst); } stm32_dmamux->iomem = iomem; -- 2.17.1
From: Etienne Carriere <etienne.carriere@st.com> Changes STM32 DMAMUX driver to defer its probe operation when reset controller is expected but has not been probed yet. Changes error traces when failing to get a system resource so that it is not printed on failure with deferred probing. Signed-off-by: Etienne Carriere <etienne.carriere@st.com> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com> --- drivers/dma/stm32-dmamux.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/dma/stm32-dmamux.c b/drivers/dma/stm32-dmamux.c index 1dfecbac64cf..12f7637e13a1 100644 --- a/drivers/dma/stm32-dmamux.c +++ b/drivers/dma/stm32-dmamux.c @@ -254,8 +254,8 @@ static int stm32_dmamux_probe(struct platform_device *pdev) stm32_dmamux->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(stm32_dmamux->clk)) { ret = PTR_ERR(stm32_dmamux->clk); - if (ret == -EPROBE_DEFER) - dev_info(&pdev->dev, "Missing controller clock\n"); + if (ret != -EPROBE_DEFER) + dev_err(&pdev->dev, "Missing clock controller\n"); return ret; } @@ -266,7 +266,11 @@ static int stm32_dmamux_probe(struct platform_device *pdev) } rst = devm_reset_control_get(&pdev->dev, NULL); - if (!IS_ERR(rst)) { + if (IS_ERR(rst)) { + ret = PTR_ERR(rst); + if (ret == -EPROBE_DEFER) + goto err_clk; + } else { reset_control_assert(rst); udelay(2); reset_control_deassert(rst); @@ -291,7 +295,12 @@ static int stm32_dmamux_probe(struct platform_device *pdev) ret = of_dma_router_register(node, stm32_dmamux_route_allocate, &stm32_dmamux->dmarouter); if (ret) - clk_disable_unprepare(stm32_dmamux->clk); + goto err_clk; + + return 0; + +err_clk: + clk_disable_unprepare(stm32_dmamux->clk); return ret; } -- 2.17.1
On 28-01-20, 10:41, Amelie Delaunay wrote:
> This series brings improvements to the DMAMUX driver with support of power
> management and probe function gets a cleanup.
Applied, thanks
--
~Vinod