Re: [PATCH v8 09/12] media: mtk-vcodec: Get rid of mtk_smi_larb_get/put

[Yong Wu]

Hi Dafna,

Thanks very much for the review.

On Wed, 2021-09-29 at 14:13 +0200, Dafna Hirschfeld wrote:
> 
> On 29.09.21 03:37, Yong Wu wrote:
> > MediaTek IOMMU has already added the device_link between the
> > consumer
> > and smi-larb device. If the vcodec device call the
> > pm_runtime_get_sync,
> > the smi-larb's pm_runtime_get_sync also be called automatically.
> > 
> > CC: Tiffany Lin <tiffany.lin@xxxxxxxxxxxx>
> > CC: Irui Wang <irui.wang@xxxxxxxxxxxx>
> > Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
> > Reviewed-by: Evan Green <evgreen@xxxxxxxxxxxx>
> > Acked-by: Tiffany Lin <tiffany.lin@xxxxxxxxxxxx>
> > Reviewed-by: Dafna Hirschfeld <dafna.hirschfeld@xxxxxxxxxxxxx>
> > ---
> >   .../platform/mtk-vcodec/mtk_vcodec_dec_pm.c   | 37 +++-----------
> > --
> >   .../platform/mtk-vcodec/mtk_vcodec_drv.h      |  3 --
> >   .../platform/mtk-vcodec/mtk_vcodec_enc.c      |  1 -
> >   .../platform/mtk-vcodec/mtk_vcodec_enc_pm.c   | 44 +++-----------
> > -----
> >   4 files changed, 10 insertions(+), 75 deletions(-)
> > 
> > diff --git a/drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_pm.c
> > b/drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_pm.c
> > index 6038db96f71c..d0bf9aa3b29d 100644
> > --- a/drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_pm.c
> > +++ b/drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_pm.c
> > @@ -8,14 +8,12 @@
> >   #include <linux/of_address.h>
> >   #include <linux/of_platform.h>
> >   #include <linux/pm_runtime.h>
> > -#include <soc/mediatek/smi.h>
> >   
> >   #include "mtk_vcodec_dec_pm.h"
> >   #include "mtk_vcodec_util.h"
> >   
> >   int mtk_vcodec_init_dec_pm(struct mtk_vcodec_dev *mtkdev)
> >   {
> > -	struct device_node *node;
> >   	struct platform_device *pdev;
> >   	struct mtk_vcodec_pm *pm;
> >   	struct mtk_vcodec_clk *dec_clk;
> > @@ -26,18 +24,7 @@ int mtk_vcodec_init_dec_pm(struct mtk_vcodec_dev
> > *mtkdev)
> >   	pm = &mtkdev->pm;
> >   	pm->mtkdev = mtkdev;
> >   	dec_clk = &pm->vdec_clk;
> > -	node = of_parse_phandle(pdev->dev.of_node, "mediatek,larb", 0);
> > -	if (!node) {
> > -		mtk_v4l2_err("of_parse_phandle mediatek,larb fail!");
> > -		return -1;
> > -	}
> >   
> > -	pdev = of_find_device_by_node(node);
> > -	of_node_put(node);
> > -	if (WARN_ON(!pdev)) {
> > -		return -1;
> > -	}
> > -	pm->larbvdec = &pdev->dev;
> >   	pdev = mtkdev->plat_dev;
> >   	pm->dev = &pdev->dev;
> >   
> > @@ -47,14 +34,11 @@ int mtk_vcodec_init_dec_pm(struct
> > mtk_vcodec_dev *mtkdev)
> >   		dec_clk->clk_info = devm_kcalloc(&pdev->dev,
> >   			dec_clk->clk_num, sizeof(*clk_info),
> >   			GFP_KERNEL);
> > -		if (!dec_clk->clk_info) {
> > -			ret = -ENOMEM;
> > -			goto put_device;
> > -		}
> > +		if (!dec_clk->clk_info)
> > +			return -ENOMEM;
> >   	} else {
> >   		mtk_v4l2_err("Failed to get vdec clock count");
> > -		ret = -EINVAL;
> > -		goto put_device;
> > +		return -EINVAL;
> >   	}
> >   
> >   	for (i = 0; i < dec_clk->clk_num; i++) {
> > @@ -63,29 +47,24 @@ int mtk_vcodec_init_dec_pm(struct
> > mtk_vcodec_dev *mtkdev)
> >   			"clock-names", i, &clk_info->clk_name);
> >   		if (ret) {
> >   			mtk_v4l2_err("Failed to get clock name id =
> > %d", i);
> > -			goto put_device;
> > +			return ret;
> >   		}
> >   		clk_info->vcodec_clk = devm_clk_get(&pdev->dev,
> >   			clk_info->clk_name);
> >   		if (IS_ERR(clk_info->vcodec_clk)) {
> >   			mtk_v4l2_err("devm_clk_get (%d)%s fail", i,
> >   				clk_info->clk_name);
> > -			ret = PTR_ERR(clk_info->vcodec_clk);
> > -			goto put_device;
> > +			return PTR_ERR(clk_info->vcodec_clk);
> >   		}
> >   	}
> >   
> >   	pm_runtime_enable(&pdev->dev);
> >   	return 0;
> > -put_device:
> > -	put_device(pm->larbvdec);
> > -	return ret;
> >   }
> >   
> >   void mtk_vcodec_release_dec_pm(struct mtk_vcodec_dev *dev)
> >   {
> >   	pm_runtime_disable(dev->pm.dev);
> > -	put_device(dev->pm.larbvdec);
> >   }
> 
> Now that functions only do  'pm_runtime_disable(dev->pm.dev);' so it
> will be more
> readable to remove the function mtk_vcodec_release_dec_pm
> and replace with pm_runtime_disable(dev->pm.dev);
> Same for the 'enc' equivalent.

Make sense. But It may be not proper if using pm_runtime_disable
as the symmetry with mtk_vcodec_init_dec_pm in the mtk_vcodec_probe.

Maybe we should move pm_runtime_enable out from mtk_vcodec_init_dec_pm
into mtk_vcodec_probe. I could do a new patch for this. Is this ok for
you?

> 
> Thanks,
> Dafna

[snip]