firmware/pmdomain: xilinx: Move ->sync_state() support to firmware driver

Rather than having the genpd provider to add device_links for each device
that gets attached, to implement the ->sync_state() support, let's rely on
fw_devlink to do this for us.

In this way, we can simplify the code by moving the ->sync_state() callback
into the firmware driver, so let's do that.

Cc: Michael Tretter <m.tretter@pengutronix.de>
Cc: Michal Simek <michal.simek@amd.com>
Tested-by: Hiago De Franco <hiago.franco@toradex.com> # Colibri iMX8X
Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> # TI AM62A,Xilinx ZynqMP ZCU106
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20250701114733.636510-15-ulf.hansson@linaro.org

Author: Ulf Hansson

drivers/firmware/xilinx/zynqmp.c

@@ -2100,6 +2100,15 @@ static void zynqmp_firmware_remove(struct platform_device *pdev)
 	platform_device_unregister(em_dev);
 }
 
+static void zynqmp_firmware_sync_state(struct device *dev)
+{
+	if (!of_device_is_compatible(dev->of_node, "xlnx,zynqmp-firmware"))
+		return;
+
+	if (zynqmp_pm_init_finalize())
+		dev_warn(dev, "failed to release power management to firmware\n");
+}
+
 static const struct of_device_id zynqmp_firmware_of_match[] = {
 	{.compatible = "xlnx,zynqmp-firmware"},
 	{.compatible = "xlnx,versal-firmware"},
@@ -2112,6 +2121,7 @@ static struct platform_driver zynqmp_firmware_driver = {
 		.name = "zynqmp_firmware",
 		.of_match_table = zynqmp_firmware_of_match,
 		.dev_groups = zynqmp_firmware_groups,
+		.sync_state = zynqmp_firmware_sync_state,
 	},
 	.probe = zynqmp_firmware_probe,
 	.remove = zynqmp_firmware_remove,

drivers/pmdomain/xilinx/zynqmp-pm-domains.c

@@ -153,14 +153,8 @@ static int zynqmp_gpd_attach_dev(struct generic_pm_domain *domain,
 				 struct device *dev)
 {
 	struct zynqmp_pm_domain *pd = to_zynqmp_pm_domain(domain);
-	struct device_link *link;
 	int ret;
 
-	link = device_link_add(dev, &domain->dev, DL_FLAG_SYNC_STATE_ONLY);
-	if (!link)
-		dev_dbg(&domain->dev, "failed to create device link for %s\n",
-			dev_name(dev));
-
 	/* If this is not the first device to attach there is nothing to do */
 	if (domain->device_count)
 		return 0;
@@ -298,19 +292,9 @@ static void zynqmp_gpd_remove(struct platform_device *pdev)
 	of_genpd_del_provider(pdev->dev.parent->of_node);
 }
 
-static void zynqmp_gpd_sync_state(struct device *dev)
-{
-	int ret;
-
-	ret = zynqmp_pm_init_finalize();
-	if (ret)
-		dev_warn(dev, "failed to release power management to firmware\n");
-}
-
 static struct platform_driver zynqmp_power_domain_driver = {
 	.driver	= {
 		.name = "zynqmp_power_controller",
-		.sync_state = zynqmp_gpd_sync_state,
 	},
 	.probe = zynqmp_gpd_probe,
 	.remove = zynqmp_gpd_remove,