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author | Pierre-Yves MORDRET <pierre-yves.mordret@st.com> | 2019-01-03 11:17:08 +0100 |
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committer | Vinod Koul <vkoul@kernel.org> | 2019-01-07 09:52:24 +0530 |
commit | 48bc73ba14bcd4080d971ed7049e81f2a4f4302e (patch) | |
tree | efd2f91e0533ca0704cd06f4a3940286f9a1ce25 /drivers/dma | |
parent | ca4c72c01e349ff6313ced02e8e66f8e691530a9 (diff) | |
download | linux-48bc73ba14bcd4080d971ed7049e81f2a4f4302e.tar.gz linux-48bc73ba14bcd4080d971ed7049e81f2a4f4302e.tar.bz2 linux-48bc73ba14bcd4080d971ed7049e81f2a4f4302e.zip |
dmaengine: stm32-dma: Add PM Runtime support
Use pm_runtime engine for clock management purpose.
Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma')
-rw-r--r-- | drivers/dma/stm32-dma.c | 58 |
1 files changed, 51 insertions, 7 deletions
diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c index 48f7c0fc1af9..ba239b529fa9 100644 --- a/drivers/dma/stm32-dma.c +++ b/drivers/dma/stm32-dma.c @@ -23,6 +23,7 @@ #include <linux/of_device.h> #include <linux/of_dma.h> #include <linux/platform_device.h> +#include <linux/pm_runtime.h> #include <linux/reset.h> #include <linux/sched.h> #include <linux/slab.h> @@ -1115,15 +1116,14 @@ static int stm32_dma_alloc_chan_resources(struct dma_chan *c) int ret; chan->config_init = false; - ret = clk_prepare_enable(dmadev->clk); - if (ret < 0) { - dev_err(chan2dev(chan), "clk_prepare_enable failed: %d\n", ret); + + ret = pm_runtime_get_sync(dmadev->ddev.dev); + if (ret < 0) return ret; - } ret = stm32_dma_disable_chan(chan); if (ret < 0) - clk_disable_unprepare(dmadev->clk); + pm_runtime_put(dmadev->ddev.dev); return ret; } @@ -1143,7 +1143,7 @@ static void stm32_dma_free_chan_resources(struct dma_chan *c) spin_unlock_irqrestore(&chan->vchan.lock, flags); } - clk_disable_unprepare(dmadev->clk); + pm_runtime_put(dmadev->ddev.dev); vchan_free_chan_resources(to_virt_chan(c)); } @@ -1243,6 +1243,12 @@ static int stm32_dma_probe(struct platform_device *pdev) return PTR_ERR(dmadev->clk); } + ret = clk_prepare_enable(dmadev->clk); + if (ret < 0) { + dev_err(&pdev->dev, "clk_prep_enable error: %d\n", ret); + return ret; + } + dmadev->mem2mem = of_property_read_bool(pdev->dev.of_node, "st,mem2mem"); @@ -1292,7 +1298,7 @@ static int stm32_dma_probe(struct platform_device *pdev) ret = dma_async_device_register(dd); if (ret) - return ret; + goto clk_free; for (i = 0; i < STM32_DMA_MAX_CHANNELS; i++) { chan = &dmadev->chan[i]; @@ -1324,20 +1330,58 @@ static int stm32_dma_probe(struct platform_device *pdev) platform_set_drvdata(pdev, dmadev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + pm_runtime_get_noresume(&pdev->dev); + pm_runtime_put(&pdev->dev); + dev_info(&pdev->dev, "STM32 DMA driver registered\n"); return 0; err_unregister: dma_async_device_unregister(dd); +clk_free: + clk_disable_unprepare(dmadev->clk); return ret; } +#ifdef CONFIG_PM +static int stm32_dma_runtime_suspend(struct device *dev) +{ + struct stm32_dma_device *dmadev = dev_get_drvdata(dev); + + clk_disable_unprepare(dmadev->clk); + + return 0; +} + +static int stm32_dma_runtime_resume(struct device *dev) +{ + struct stm32_dma_device *dmadev = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(dmadev->clk); + if (ret) { + dev_err(dev, "failed to prepare_enable clock\n"); + return ret; + } + + return 0; +} +#endif + +static const struct dev_pm_ops stm32_dma_pm_ops = { + SET_RUNTIME_PM_OPS(stm32_dma_runtime_suspend, + stm32_dma_runtime_resume, NULL) +}; + static struct platform_driver stm32_dma_driver = { .driver = { .name = "stm32-dma", .of_match_table = stm32_dma_of_match, + .pm = &stm32_dma_pm_ops, }, }; |