Re: [v3] PCI: tegra194: Fix debugfs directory creation when CONFIG_PCIEASPM is disabled

From: Hans Zhang
Date: Mon Apr 07 2025 - 22:03:57 EST




On 2025/4/8 03:43, Christophe JAILLET wrote:
Hi,

Nitpick: PATCH is missing within the [] in the subject.


Hi Christophe,

I will pay attention in the future.


Le 07/04/2025 à 14:43, Hans Zhang a écrit :
Previously, the debugfs directory was unconditionally created in
tegra_pcie_config_rp() regardless of the CONFIG_PCIEASPM setting.
This led to unnecessary directory creation when ASPM support was disabled.

Move the debugfs directory creation into init_debugfs() which is
conditionally compiled based on CONFIG_PCIEASPM. This ensures:
- The directory is only created when ASPM-related debugfs entries are
   needed.
- Proper error handling for directory creation failures.
- Avoids cluttering debugfs with empty directories when ASPM is disabled.

Signed-off-by: Hans Zhang <18255117159@xxxxxxx>
---
Changes since v2:
https://lore.kernel.org/linux-pci/20250406134355.49036-1-18255117159@xxxxxxx/

- Maintainer recommends ignoring the devm_kasprintf return value. The
   module should still work correctly. So just a return;

Note, that I'm not a maintainer ;-)


Maybe I made a mistake. ;-)

No.72 Christophe JAILLET <christophe ! jaillet () wanadoo ! fr> 2104(0.17%) @Hobbyists @French

Best regards,
Hans

For what it worth:

Reviewed-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>


CJ

Changes since v1:
https://lore.kernel.org/linux-pci/20250405145459.26800-1-18255117159@xxxxxxx/

- The first version was committed incorrectly because the judgment
   parameter in "debugfs_remove_recursive" was not noticed.
---
  drivers/pci/controller/dwc/pcie-tegra194.c | 19 ++++++++++---------
  1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 5103995cd6c7..bc419688527a 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -713,7 +713,16 @@ static void init_host_aspm(struct tegra_pcie_dw *pcie)
  static void init_debugfs(struct tegra_pcie_dw *pcie)
  {
-    debugfs_create_devm_seqfile(pcie->dev, "aspm_state_cnt", pcie->debugfs,
+    struct device *dev = pcie->dev;
+    char *name;
+
+    name = devm_kasprintf(dev, GFP_KERNEL, "%pOFP", dev->of_node);
+    if (!name)
+        return;
+
+    pcie->debugfs = debugfs_create_dir(name, NULL);
+
+    debugfs_create_devm_seqfile(dev, "aspm_state_cnt", pcie->debugfs,
                      aspm_state_cnt);
  }
  #else
@@ -1634,7 +1643,6 @@ static void tegra_pcie_deinit_controller(struct tegra_pcie_dw *pcie)
  static int tegra_pcie_config_rp(struct tegra_pcie_dw *pcie)
  {
      struct device *dev = pcie->dev;
-    char *name;
      int ret;
      pm_runtime_enable(dev);
@@ -1664,13 +1672,6 @@ static int tegra_pcie_config_rp(struct tegra_pcie_dw *pcie)
          goto fail_host_init;
      }
-    name = devm_kasprintf(dev, GFP_KERNEL, "%pOFP", dev->of_node);
-    if (!name) {
-        ret = -ENOMEM;
-        goto fail_host_init;
-    }
-
-    pcie->debugfs = debugfs_create_dir(name, NULL);
      init_debugfs(pcie);
      return ret;

base-commit: a8662bcd2ff152bfbc751cab20f33053d74d0963