Re: [PATCH v2 2/5] firmware: tegra: bpmp: Add tegra_bpmp_get_with_id() function

[Mikko Perttunen <mperttunen@nvidia.com>]

On Saturday, March 21, 2026 7:54 AM Thierry Reding wrote:
> From: Thierry Reding <treding@nvidia.com>
> 
> Some device tree bindings need to specify a parameter along with a BPMP
> phandle reference to designate the ID associated with a given controller
> that needs to interoperate with BPMP. Typically this is specified as an
> extra cell in the nvidia,bpmp property, so add a helper to parse this ID
> while resolving the phandle reference.
> 
> Signed-off-by: Thierry Reding <treding@nvidia.com>
> ---
>  drivers/firmware/tegra/bpmp.c | 34 ++++++++++++++++++++++++++++++++++
>  include/soc/tegra/bpmp.h      |  1 +
>  2 files changed, 35 insertions(+)
> 
> diff --git a/drivers/firmware/tegra/bpmp.c b/drivers/firmware/tegra/bpmp.c
> index e74bba7ccc44..753472b53bd8 100644
> --- a/drivers/firmware/tegra/bpmp.c
> +++ b/drivers/firmware/tegra/bpmp.c
> @@ -32,6 +32,40 @@ channel_to_ops(struct tegra_bpmp_channel *channel)
>  	return bpmp->soc->ops;
>  }
>  
> +struct tegra_bpmp *tegra_bpmp_get_with_id(struct device *dev, unsigned int 
*id)
> +{
> +	struct platform_device *pdev;
> +	struct of_phandle_args args;
> +	struct tegra_bpmp *bpmp;
> +	int err;
> +
> +	err = __of_parse_phandle_with_args(dev->of_node, "nvidia,bpmp", NULL,
> +					   1, 0, &args);
> +	if (err < 0)
> +		return ERR_PTR(err);
> +
> +	pdev = of_find_device_by_node(args.np);
> +	if (!pdev) {
> +		bpmp = ERR_PTR(-ENODEV);
> +		goto put;
> +	}
> +
> +	bpmp = platform_get_drvdata(pdev);
> +	if (!bpmp) {
> +		bpmp = ERR_PTR(-EPROBE_DEFER);
> +		put_device(&pdev->dev);
> +		goto put;
> +	}
> +
> +	if (id)
> +		*id = args.args[0];
> +
> +put:
> +	of_node_put(args.np);
> +	return bpmp;
> +}
> +EXPORT_SYMBOL_GPL(tegra_bpmp_get_with_id);
> +
>  struct tegra_bpmp *tegra_bpmp_get(struct device *dev)
>  {
>  	struct platform_device *pdev;
> diff --git a/include/soc/tegra/bpmp.h b/include/soc/tegra/bpmp.h
> index f5e4ac5b8cce..424188c100d9 100644
> --- a/include/soc/tegra/bpmp.h
> +++ b/include/soc/tegra/bpmp.h
> @@ -127,6 +127,7 @@ struct tegra_bpmp_message {
>  
>  #if IS_ENABLED(CONFIG_TEGRA_BPMP)
>  struct tegra_bpmp *tegra_bpmp_get(struct device *dev);
> +struct tegra_bpmp *tegra_bpmp_get_with_id(struct device *dev, unsigned int 
*id);

Should add a stub function in the #else branch, as well.

>  void tegra_bpmp_put(struct tegra_bpmp *bpmp);
>  int tegra_bpmp_transfer_atomic(struct tegra_bpmp *bpmp,
>  			       struct tegra_bpmp_message *msg);
> -- 
> 2.52.0
> 
>