thunderbolt: Log a warning if device links are not found

The software connection manager needs the device links in order to
establish the tunnels before the native protocols so log a warning if
they are not found.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

1 files changed, 17 insertions, 7 deletions

diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
index 62b26b7998fd..ffbae134589b 100644
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -2366,12 +2366,13 @@ static const struct tb_cm_ops tb_cm_ops = {
  * downstream ports and the NHI so that the device core will make sure
  * NHI is resumed first before the rest.
  */
-static void tb_apple_add_links(struct tb_nhi *nhi)
+static bool tb_apple_add_links(struct tb_nhi *nhi)
 {
 	struct pci_dev *upstream, *pdev;
+	bool ret;
 
 	if (!x86_apple_machine)
-		return;
+		return false;
 
 	switch (nhi->pdev->device) {
 	case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
@@ -2380,26 +2381,27 @@ static void tb_apple_add_links(struct tb_nhi *nhi)
 	case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI:
 		break;
 	default:
-		return;
+		return false;
 	}
 
 	upstream = pci_upstream_bridge(nhi->pdev);
 	while (upstream) {
 		if (!pci_is_pcie(upstream))
-			return;
+			return false;
 		if (pci_pcie_type(upstream) == PCI_EXP_TYPE_UPSTREAM)
 			break;
 		upstream = pci_upstream_bridge(upstream);
 	}
 
 	if (!upstream)
-		return;
+		return false;
 
 	/*
 	 * For each hotplug downstream port, create add device link
 	 * back to NHI so that PCIe tunnels can be re-established after
 	 * sleep.
 	 */
+	ret = false;
 	for_each_pci_bridge(pdev, upstream->subordinate) {
 		const struct device_link *link;
 
@@ -2415,11 +2417,14 @@ static void tb_apple_add_links(struct tb_nhi *nhi)
 		if (link) {
 			dev_dbg(&nhi->pdev->dev, "created link from %s\n",
 				dev_name(&pdev->dev));
+			ret = true;
 		} else {
 			dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n",
 				 dev_name(&pdev->dev));
 		}
 	}
+
+	return ret;
 }
 
 struct tb *tb_probe(struct tb_nhi *nhi)
@@ -2446,8 +2451,13 @@ struct tb *tb_probe(struct tb_nhi *nhi)
 
 	tb_dbg(tb, "using software connection manager\n");
 
-	tb_apple_add_links(nhi);
-	tb_acpi_add_links(nhi);
+	/*
+	 * Device links are needed to make sure we establish tunnels
+	 * before the PCIe/USB stack is resumed so complain here if we
+	 * found them missing.
+	 */
+	if (!tb_apple_add_links(nhi) && !tb_acpi_add_links(nhi))
+		tb_warn(tb, "device links to tunneled native ports are missing!\n");
 
 	return tb;
 }