[PATCH V4 01/13] DMA: PL330: Add support runtime PM for PL330 DMAC

[Jassi Brar]

On Wed, Jul 20, 2011 at 4:16 PM, Boojin Kim <boojin.kim at samsung.com> wrote:
> Signed-off-by: Boojin Kim <boojin.kim at samsung.com>
> Cc: Vinod Koul <vinod.koul at intel.com>
> Cc: Dan Williams <dan.j.williams at intel.com>
> Signed-off-by: Kukjin Kim <kgene.kim at samsung.com>

Acked-by: Jassi Brar <jassisinghbrar at gmail.com>


> ---
>  drivers/dma/pl330.c |   75 +++++++++++++++++++++++++++++++++++++++++++++++++-
>  1 files changed, 73 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
> index 6abe1ec..b7ecf47 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[0]; /* 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);
> @@ -763,8 +790,6 @@ 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,
> @@ -825,6 +850,13 @@ 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;
> @@ -838,10 +870,49 @@ 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,
> --
> 1.7.1
>
>