Re: [PATCH v5] reset: mediatek: Move mediatek system clock reset to reset folder

[Stephen Boyd]

Quoting Bo-Chen Chen (2022-10-07 03:48:42)
> To manager mediatek system clock reset easier, we move the driver to
> drivers/reset.
> 
> - Create reset/mediatek folder.
> - Move clk/mediatek/reset.c to reset/mediatek/reset-mediatek-sysclk.c
> - Because we don't want to build in unsed static variable (For example,
>   if we use mt8186, we don't want to build in the variable of MT8195.),
>   we use clk KConfig to do this.
> - Move reset data which are scattered around the mediatek drivers to
>   reset-mtxxxx.c.
> - For mtk clk drivers which support device, we can ues
>   mtk_reset_controller_register() to register reset controller using
>   auxiliary bus.
> - For mtk clk drivers which do not support device (only support
>   device_node), we use mtk_reset_{init/remove}_with_node to register
>   reset controller.
> 
> Signed-off-by: Bo-Chen Chen <rex-bc.chen@xxxxxxxxxxxx>
[...]
> diff --git a/drivers/clk/mediatek/Kconfig b/drivers/clk/mediatek/Kconfig
> index 843cea0c7a44..bcd073ada0e9 100644
> --- a/drivers/clk/mediatek/Kconfig
> +++ b/drivers/clk/mediatek/Kconfig
> @@ -8,6 +8,8 @@ menu "Clock driver for MediaTek SoC"
>  config COMMON_CLK_MEDIATEK
>         tristate
>         select RESET_CONTROLLER
> +       select RESET_MEDIATEK_SYSCLK

Is this select necessary?

> +       select AUXILIARY_BUS
>         help
>           MediaTek SoCs' clock support.
>  
> diff --git a/drivers/clk/mediatek/clk-mtk.c b/drivers/clk/mediatek/clk-mtk.c
> index d31f01d0ba1c..61b7ee23738a 100644
> --- a/drivers/clk/mediatek/clk-mtk.c
> +++ b/drivers/clk/mediatek/clk-mtk.c
> @@ -444,6 +444,63 @@ void mtk_clk_unregister_dividers(const struct mtk_clk_divider *mcds, int num,
>  }
>  EXPORT_SYMBOL_GPL(mtk_clk_unregister_dividers);
>  
> +static void mtk_reset_unregister_adev(void *_adev)
> +{
> +       struct auxiliary_device *adev = _adev;
> +
> +       auxiliary_device_delete(adev);
> +}
> +
> +static void mtk_reset_adev_release(struct device *dev)
> +{
> +       struct auxiliary_device *adev = to_auxiliary_dev(dev);
> +
> +       auxiliary_device_uninit(adev);
> +
> +       kfree(adev);
> +}
> +
> +static struct auxiliary_device *mtk_reset_adev_alloc(struct device *dev, const char *name)
> +{
> +       struct auxiliary_device *adev;
> +       int ret;
> +
> +       adev = kzalloc(sizeof(*adev), GFP_KERNEL);
> +       if (!adev)
> +               return ERR_PTR(-ENOMEM);
> +
> +       adev->name = name;
> +       adev->dev.parent = dev;
> +       adev->dev.release = mtk_reset_adev_release;
> +
> +       ret = auxiliary_device_init(adev);
> +       if (ret) {
> +               kfree(adev);
> +               return ERR_PTR(ret);
> +       }
> +
> +       return adev;
> +}
> +
> +int mtk_reset_controller_register(struct device *dev, const char *name)
> +{
> +       struct auxiliary_device *adev;
> +       int ret;
> +
> +       adev = mtk_reset_adev_alloc(dev, name);
> +       if (IS_ERR(adev))
> +               return PTR_ERR(adev);
> +
> +       ret = auxiliary_device_add(adev);
> +       if (ret) {
> +               auxiliary_device_uninit(adev);
> +               return ret;
> +       }
> +
> +       return devm_add_action_or_reset(dev, mtk_reset_unregister_adev, adev);
> +}
> +EXPORT_SYMBOL_GPL(mtk_reset_controller_register);
> +
>  int mtk_clk_simple_probe(struct platform_device *pdev)
>  {
>         const struct mtk_clk_desc *mcd;
> @@ -470,9 +527,8 @@ int mtk_clk_simple_probe(struct platform_device *pdev)
>  
>         platform_set_drvdata(pdev, clk_data);
>  
> -       if (mcd->rst_desc) {
> -               r = mtk_register_reset_controller_with_dev(&pdev->dev,
> -                                                          mcd->rst_desc);
> +       if (mcd->rst_name) {
> +               r = mtk_reset_controller_register(&pdev->dev, mcd->rst_name);
>                 if (r)
>                         goto unregister_clks;
>         }

Can you split this part off to a different patch? It would make it
easier to review. And then you stack the reset part of the patch after
this.

> diff --git a/drivers/clk/mediatek/clk-mtk.h b/drivers/clk/mediatek/clk-mtk.h
> index 63ae7941aa92..9578643ef5a2 100644
> --- a/drivers/clk/mediatek/clk-mtk.h
> +++ b/drivers/clk/mediatek/clk-mtk.h
> @@ -7,14 +7,14 @@
>  #ifndef __DRV_CLK_MTK_H
>  #define __DRV_CLK_MTK_H
>  
> +#include <linux/auxiliary_bus.h>
>  #include <linux/clk-provider.h>
>  #include <linux/io.h>
>  #include <linux/kernel.h>
> +#include <linux/reset/reset-mediatek-sysclk.h>
>  #include <linux/spinlock.h>
>  #include <linux/types.h>
>  
> -#include "reset.h"
> -
>  #define MAX_MUX_GATE_BIT       31
>  #define INVALID_MUX_GATE_BIT   (MAX_MUX_GATE_BIT + 1)
>  
> @@ -195,10 +195,12 @@ void mtk_clk_unregister_ref2usb_tx(struct clk_hw *hw);
>  struct mtk_clk_desc {
>         const struct mtk_gate *clks;
>         size_t num_clks;
> -       const struct mtk_clk_rst_desc *rst_desc;
> +       char *rst_name;
>  };
>  
>  int mtk_clk_simple_probe(struct platform_device *pdev);
>  int mtk_clk_simple_remove(struct platform_device *pdev);
>  
> +int mtk_reset_controller_register(struct device *dev, const char *name);
> +
>  #endif /* __DRV_CLK_MTK_H */
> diff --git a/drivers/clk/mediatek/reset.c b/drivers/clk/mediatek/reset.c
> deleted file mode 100644
> index 290ceda84ce4..000000000000
> --- a/drivers/clk/mediatek/reset.c
> +++ /dev/null

This file could probably be deleted in yet another patch once nobody is
using it.