[PATCH v2 05/13] ARM: psci: client: add PSCI version/method parameters

[Ahmad Fatoum <a.fatoum@barebox.org>]

Populate device parameters with this information, so the bfetch command
can make use of it.

Signed-off-by: Ahmad Fatoum <a.fatoum@barebox.org>
---
v1 -> v2:
  - use IS_ERR_OR_NULL to guard param getting
  - use new get_param_value helper
---
 arch/arm/cpu/psci-client.c | 17 +++++++++++++----
 include/param.h            | 10 ++++++++++
 2 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/arch/arm/cpu/psci-client.c b/arch/arm/cpu/psci-client.c
index 4c26beacb9bb..75cc3f59e0c1 100644
--- a/arch/arm/cpu/psci-client.c
+++ b/arch/arm/cpu/psci-client.c
@@ -117,6 +117,7 @@ static int of_psci_do_fixup(struct device_node *root, void *method)
 
 static int __init psci_probe(struct device *dev)
 {
+	struct param_d *param;
 	const char *method;
 	ulong of_version, actual_version;
 	int ret;
@@ -154,8 +155,12 @@ static int __init psci_probe(struct device *dev)
 	psci_invoke(ARM_PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0, &actual_version);
 	version = actual_version;
 
-	dev_info(dev, "detected version %u.%u\n",
-		 version >> 16, version & 0xffff);
+	param = dev_add_param_fixed(dev, "version", "%u.%u",
+				    version >> 16, version & 0xffff);
+	if (!IS_ERR_OR_NULL(param))
+		dev_info(dev, "detected version %s\n", get_param_value(param));
+
+	dev_add_param_fixed(dev, "method", "%s", method);
 
 	if (actual_version != of_version)
 		of_register_fixup(of_psci_do_fixup, (void *)method);
@@ -170,11 +175,15 @@ static int __init psci_probe(struct device *dev)
 	restart.priority = 400;
 
 	ret = restart_handler_register(&restart);
-	if (ret)
+	if (ret) {
 		dev_warn(dev, "error registering restart handler: %pe\n",
 			 ERR_PTR(ret));
+		return ret;
+	}
 
-	return ret;
+	dev_add_alias(dev, "psci");
+
+	return 0;
 }
 
 static __maybe_unused struct of_device_id psci_dt_ids[] = {
diff --git a/include/param.h b/include/param.h
index 1bf04015f266..c12151134752 100644
--- a/include/param.h
+++ b/include/param.h
@@ -253,6 +253,16 @@ static inline int bobject_param_set_generic(bobject_t bobj, struct param_d *p,
 }
 #endif
 
+static inline const char *get_param_value(struct param_d *param)
+{
+	if (!IS_ENABLED(CONFIG_PARAMETER))
+		return NULL;
+	if (IS_ERR_OR_NULL(param))
+		return ERR_CAST(param);
+
+	return param->get(param->bobj, param);
+}
+
 int param_set_readonly(struct param_d *p, void *priv);
 
 /*
-- 
2.39.5