Re: [PATCH v7 11/13] clk: mediatek: mt8183: switch mmsys to platform device probing

[CK Hu]

Hi, Matthias:

On Thu, 2020-02-13 at 21:19 +0100, matthias.bgg@xxxxxxxxxx wrote:
> From: Matthias Brugger <mbrugger@xxxxxxxx>
> 
> Switch probing for the MMSYS to support invocation to a
> plain paltform device. The driver will be probed by the DRM subsystem.
> 
> Signed-off-by: Matthias Brugger <mbrugger@xxxxxxxx>
> 
> ---
> 
> Changes in v7:
> - free clk_data->clks as well
> - get rid of private data structure
> 
> Changes in v6: None
> Changes in v5: None
> Changes in v4: None
> Changes in v3: None
> Changes in v2: None
> 
>  drivers/clk/mediatek/clk-mt8183-mm.c | 30 ++++++++++++++++++----------
>  1 file changed, 20 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/clk/mediatek/clk-mt8183-mm.c b/drivers/clk/mediatek/clk-mt8183-mm.c
> index 720c696b506d..7576cd231be3 100644
> --- a/drivers/clk/mediatek/clk-mt8183-mm.c
> +++ b/drivers/clk/mediatek/clk-mt8183-mm.c
> @@ -3,8 +3,10 @@
>  // Copyright (c) 2018 MediaTek Inc.
>  // Author: Weiyi Lu <weiyi.lu@xxxxxxxxxxxx>
>  
> +#include <linux/module.h>
>  #include <linux/clk-provider.h>
>  #include <linux/platform_device.h>
> +#include <linux/slab.h>
>  
>  #include "clk-mtk.h"
>  #include "clk-gate.h"
> @@ -85,27 +87,35 @@ static const struct mtk_gate mm_clks[] = {
>  static int clk_mt8183_mm_probe(struct platform_device *pdev)
>  {
>  	struct clk_onecell_data *clk_data;
> -	struct device_node *node = pdev->dev.of_node;
> +	struct device_node *node = pdev->dev.parent->of_node;
> +
> +	clk_data = devm_kzalloc(&pdev->dev, sizeof(*clk_data), GFP_KERNEL);

I think this is redundant.

> +	if (!clk_data)
> +		return -ENOMEM;
>  
>  	clk_data = mtk_alloc_clk_data(CLK_MM_NR_CLK);
> +	platform_set_drvdata(pdev, clk_data);
>  
> -	mtk_clk_register_gates(node, mm_clks, ARRAY_SIZE(mm_clks),
> -			clk_data);
> +	mtk_clk_register_gates(node, mm_clks, ARRAY_SIZE(mm_clks), clk_data);
>  
>  	return of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
>  }
>  
> -static const struct of_device_id of_match_clk_mt8183_mm[] = {
> -	{ .compatible = "mediatek,mt8183-mmsys", },
> -	{}
> -};
> +static int clk_mt8183_mm_remove(struct platform_device *pdev)
> +{
> +	struct clk_onecell_data *clk_data = platform_get_drvdata(pdev);
> +
> +	kfree(clk_data->clks);
> +	kfree(clk_data);

These two statement looks like a reverse of mtk_alloc_clk_data() and
exist in many files. It is worth to have a function (maybe
mtk_free_clk_data()) to do this.

In addition, should we undo what is done in clk_mt8183_mm_probe() such
as mtk_clk_register_gates() and of_clk_add_provider()?

Regards,
CK

> +
> +	return 0;
> +}
>  
>  static struct platform_driver clk_mt8183_mm_drv = {
>  	.probe = clk_mt8183_mm_probe,
> +	.remove = clk_mt8183_mm_remove,
>  	.driver = {
>  		.name = "clk-mt8183-mm",
> -		.of_match_table = of_match_clk_mt8183_mm,
>  	},
>  };
> -
> -builtin_platform_driver(clk_mt8183_mm_drv);
> +module_platform_driver(clk_mt8183_mm_drv);