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

Thierry Reding
2026-03-20T22:54:51Z

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);
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