DMA: PL330: Add support runtime PM for PL330 DMAC

Signed-off-by: Boojin Kim <boojin.kim@samsung.com>
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 73 insertions, 2 deletions

diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 00eee59e8b33..0b99af18f9a1 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -17,6 +17,7 @@
 #include <linux/interrupt.h>
 #include <linux/amba/bus.h>
 #include <linux/amba/pl330.h>
+#include <linux/pm_runtime.h>
 
 #define NR_DEFAULT_DESC 16
 
@@ -83,6 +84,8 @@ struct dma_pl330_dmac {
 
         /* Peripheral channels connected to this DMAC */
         struct dma_pl330_chan *peripherals; /* keep at end */
+
+        struct clk *clk;
 };
 
 struct dma_pl330_desc {
@@ -696,6 +699,30 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
                 goto probe_err1;
         }
 
+        pdmac->clk = clk_get(&adev->dev, "dma");
+        if (IS_ERR(pdmac->clk)) {
+                dev_err(&adev->dev, "Cannot get operation clock.\n");
+                ret = -EINVAL;
+                goto probe_err1;
+        }
+
+        amba_set_drvdata(adev, pdmac);
+
+#ifdef CONFIG_PM_RUNTIME
+        /* to use the runtime PM helper functions */
+        pm_runtime_enable(&adev->dev);
+
+        /* enable the power domain */
+        if (pm_runtime_get_sync(&adev->dev)) {
+                dev_err(&adev->dev, "failed to get runtime pm\n");
+                ret = -ENODEV;
+                goto probe_err1;
+        }
+#else
+        /* enable dma clk */
+        clk_enable(pdmac->clk);
+#endif
+
         irq = adev->irq[0];
         ret = request_irq(irq, pl330_irq_handler, 0,
                         dev_name(&adev->dev), pi);
@@ -771,8 +798,6 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id)
                 goto probe_err4;
         }
 
-        amba_set_drvdata(adev, pdmac);
-
         dev_info(&adev->dev,
                 "Loaded driver for PL330 DMAC-%d\n", adev->periphid);
         dev_info(&adev->dev,
@@ -833,6 +858,13 @@ static int __devexit pl330_remove(struct amba_device *adev)
         res = &adev->res;
         release_mem_region(res->start, resource_size(res));
 
+#ifdef CONFIG_PM_RUNTIME
+        pm_runtime_put(&adev->dev);
+        pm_runtime_disable(&adev->dev);
+#else
+        clk_disable(pdmac->clk);
+#endif
+
         kfree(pdmac);
 
         return 0;
@@ -846,10 +878,49 @@ static struct amba_id pl330_ids[] = {
         { 0, 0 },
 };
 
+#ifdef CONFIG_PM_RUNTIME
+static int pl330_runtime_suspend(struct device *dev)
+{
+        struct dma_pl330_dmac *pdmac = dev_get_drvdata(dev);
+
+        if (!pdmac) {
+                dev_err(dev, "failed to get dmac\n");
+                return -ENODEV;
+        }
+
+        clk_disable(pdmac->clk);
+
+        return 0;
+}
+
+static int pl330_runtime_resume(struct device *dev)
+{
+        struct dma_pl330_dmac *pdmac = dev_get_drvdata(dev);
+
+        if (!pdmac) {
+                dev_err(dev, "failed to get dmac\n");
+                return -ENODEV;
+        }
+
+        clk_enable(pdmac->clk);
+
+        return 0;
+}
+#else
+#define pl330_runtime_suspend   NULL
+#define pl330_runtime_resume    NULL
+#endif /* CONFIG_PM_RUNTIME */
+
+static const struct dev_pm_ops pl330_pm_ops = {
+        .runtime_suspend = pl330_runtime_suspend,
+        .runtime_resume = pl330_runtime_resume,
+};
+
 static struct amba_driver pl330_driver = {
         .drv = {
                 .owner = THIS_MODULE,
                 .name = "dma-pl330",
+                .pm = &pl330_pm_ops,
         },
         .id_table = pl330_ids,
         .probe = pl330_probe,