[PATCH v3 2/5] phy: qcom: qmp-pcie: Add multiple power-domains support

Qiang Yu
2026-04-13T06:26:24Z

The Glymur SoC's 3rd PCIe instance supports 8-lane mode using two PHYs in
a bifurcated configuration. Each PHY has its own power domain (phy_gdsc)
that must be powered on before initialization per hardware requirements.

Current PHY power management assumes a single power domain per PHY,
preventing proper setup for this dual-PHY scenario. Add support for
multiple power domains by using devm_pm_domain_attach_list() to attach
power domains manually, while maintaining compatibility with single
power domain PHYs.

Enable runtime PM to allow power domain control when the PCIe driver
calls phy_power_on/phy_power_off:

- Single power domain: QMP PHY platform device directly attaches to
power domain and controls it during runtime resume/suspend
- Multiple power domains: devm_pm_domain_attach_list() creates virtual
devices as power domain suppliers, linked to the QMP PHY platform
device as consumer

This ensures power domains are properly attached and turned on/off
for both single and multiple power domain configurations.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Qiang Yu <qiang.yu@oss.qualcomm.com>
---
drivers/phy/qualcomm/phy-qcom-qmp-pcie.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
index fed2fc9bb31108d51f88d34f3379c7744681f485..424c935e27a8766e1e26762bd3d7df527c1520e3 100644
--- a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
+++ b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
@@ -17,6 +17,7 @@
#include <linux/phy/pcie.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>
@@ -5329,6 +5330,7 @@ static int qmp_pcie_parse_dt(struct qmp_pcie *qmp)

static int qmp_pcie_probe(struct platform_device *pdev)
{
+ struct dev_pm_domain_list *pd_list;
struct device *dev = &pdev->dev;
struct phy_provider *phy_provider;
struct device_node *np;
@@ -5348,6 +5350,16 @@ static int qmp_pcie_probe(struct platform_device *pdev)
WARN_ON_ONCE(!qmp->cfg->pwrdn_ctrl);
WARN_ON_ONCE(!qmp->cfg->phy_status);

+ ret = devm_pm_domain_attach_list(dev, NULL, &pd_list);
+ if (ret < 0 && ret != -EEXIST) {
+ dev_err(dev, "Failed to attach power domain\n");
+ return ret;
+ }
+
+ ret = devm_pm_runtime_enable(dev);
+ if (ret)
+ return ret;
+
ret = qmp_pcie_clk_init(qmp);
if (ret)
return ret;

--
2.34.1