[PATCH] ARM: imx: register reset controller from a platform driver

[Saravana Kannan]

On Tue, Oct 5, 2021 at 3:06 AM Philipp Zabel <p.zabel at pengutronix.de> wrote:
>
> Starting with commit 6b2117ad65f1 ("of: property: fw_devlink: Add
> support for "resets" and "pwms""), the imx-drm driver fails to load
> due to forever dormant devlinks to the reset-controller node. This
> node was never associated with a struct device.
>
> Add a platform device to allow fw_devnode to activate the devlinks.
>
> Fixes: 6b2117ad65f1 ("of: property: fw_devlink: Add support for "resets" and "pwms"")
> Signed-off-by: Philipp Zabel <p.zabel at pengutronix.de>
> ---
>  arch/arm/mach-imx/src.c | 40 +++++++++++++++++++++++++++++++---------
>  1 file changed, 31 insertions(+), 9 deletions(-)
>
> diff --git a/arch/arm/mach-imx/src.c b/arch/arm/mach-imx/src.c
> index 95fd1fbb0826..59a8e8cc4469 100644
> --- a/arch/arm/mach-imx/src.c
> +++ b/arch/arm/mach-imx/src.c
> @@ -9,6 +9,7 @@
>  #include <linux/iopoll.h>
>  #include <linux/of.h>
>  #include <linux/of_address.h>
> +#include <linux/platform_device.h>
>  #include <linux/reset-controller.h>
>  #include <linux/smp.h>
>  #include <asm/smp_plat.h>
> @@ -81,11 +82,6 @@ static const struct reset_control_ops imx_src_ops = {
>         .reset = imx_src_reset_module,
>  };
>
> -static struct reset_controller_dev imx_reset_controller = {
> -       .ops = &imx_src_ops,
> -       .nr_resets = ARRAY_SIZE(sw_reset_bits),
> -};
> -
>  static void imx_gpcv2_set_m_core_pgc(bool enable, u32 offset)
>  {
>         writel_relaxed(enable, gpc_base + offset);
> @@ -177,10 +173,6 @@ void __init imx_src_init(void)
>         src_base = of_iomap(np, 0);
>         WARN_ON(!src_base);
>
> -       imx_reset_controller.of_node = np;
> -       if (IS_ENABLED(CONFIG_RESET_CONTROLLER))
> -               reset_controller_register(&imx_reset_controller);
> -
>         /*
>          * force warm reset sources to generate cold reset
>          * for a more reliable restart
> @@ -214,3 +206,33 @@ void __init imx7_src_init(void)
>         if (!gpc_base)
>                 return;
>  }
> +
> +static const struct of_device_id imx_src_dt_ids[] = {
> +       { .compatible = "fsl,imx51-src" },
> +       { /* sentinel */ }
> +};
> +
> +static int imx_src_probe(struct platform_device *pdev)
> +{
> +       struct reset_controller_dev *rcdev;
> +
> +       rcdev = devm_kzalloc(&pdev->dev, sizeof(*rcdev), GFP_KERNEL);
> +       if (!rcdev)
> +               return -ENOMEM;
> +
> +       rcdev->ops = &imx_src_ops;
> +       rcdev->dev = &pdev->dev;
> +       rcdev->of_node = pdev->dev.of_node;
> +       rcdev->nr_resets = ARRAY_SIZE(sw_reset_bits);
> +
> +       return devm_reset_controller_register(&pdev->dev, rcdev);
> +}
> +
> +static struct platform_driver imx_src_driver = {
> +       .driver = {
> +               .name = "imx-src",
> +               .of_match_table = imx_src_dt_ids,
> +       },
> +       .probe = imx_src_probe,
> +};
> +builtin_platform_driver(imx_src_driver);
>
> base-commit: 6880fa6c56601bb8ed59df6c30fd390cc5f6dd8f

Reviewed-by: Saravana Kannan <saravanak at google.com>

-Saravana