linux-kernel - [PATCH 1/1] platform/x86/amd/pmf: Added a module parameter to disable the Smart PC function

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Message-ID: <20260121143519.12318-1-xglooom@gmail.com>
Date: Wed, 21 Jan 2026 19:35:19 +0500
From: Alexey Zagorodnikov <xglooom@...il.com>
To: platform-driver-x86@...r.kernel.org
Cc: mario.limonciello@....com,
	Alexey Zagorodnikov <xglooom@...il.com>,
	Shyam Sundar S K <Shyam-sundar.S-k@....com>,
	Hans de Goede <hansg@...nel.org>,
	Ilpo Järvinen <ilpo.jarvinen@...ux.intel.com>,
	linux-kernel@...r.kernel.org
Subject: [PATCH 1/1] platform/x86/amd/pmf: Added a module parameter to disable the Smart PC function

Addresses a low power limits issue on HP ZBook Ultra G1a [1]

If vendor firmware capped APU power limits with 3rd-party AC adapters,
the user can disable the Smart PC function via the module parameter

Link: https://gitlab.freedesktop.org/drm/amd/-/issues/4868 [1]
Signed-off-by: Alexey Zagorodnikov <xglooom@...il.com>
---
 drivers/platform/x86/amd/pmf/core.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/platform/x86/amd/pmf/core.c b/drivers/platform/x86/amd/pmf/core.c
index 8fc293c9c5380..ee7b3adc63a02 100644
--- a/drivers/platform/x86/amd/pmf/core.c
+++ b/drivers/platform/x86/amd/pmf/core.c
@@ -53,6 +53,10 @@ static bool force_load;
 module_param(force_load, bool, 0444);
 MODULE_PARM_DESC(force_load, "Force load this driver on supported older platforms (experimental)");
 
+static bool smart_pc_support = true;
+module_param(smart_pc_support, bool, 0444);
+MODULE_PARM_DESC(smart_pc_support, "Smart PC Support (default = true)");
+
 static int amd_pmf_pwr_src_notify_call(struct notifier_block *nb, unsigned long event, void *data)
 {
 	struct amd_pmf_dev *pmf = container_of(nb, struct amd_pmf_dev, pwr_src_notifier);
@@ -362,11 +366,15 @@ static void amd_pmf_init_features(struct amd_pmf_dev *dev)
 		dev_dbg(dev->dev, "SPS enabled and Platform Profiles registered\n");
 	}
 
-	amd_pmf_init_smart_pc(dev);
-	if (dev->smart_pc_enabled) {
-		dev_dbg(dev->dev, "Smart PC Solution Enabled\n");
-		/* If Smart PC is enabled, no need to check for other features */
-		return;
+	if (smart_pc_support) {
+		amd_pmf_init_smart_pc(dev);
+		if (dev->smart_pc_enabled) {
+			dev_dbg(dev->dev, "Smart PC Solution Enabled\n");
+			/* If Smart PC is enabled, no need to check for other features */
+			return;
+		}
+	} else {
+		dev->smart_pc_enabled = false;
 	}
 
 	if (is_apmf_func_supported(dev, APMF_FUNC_AUTO_MODE)) {
-- 
2.52.0