[PATCH v4 0/5] PCI: dwc: Rework the error handling of dw_pcie_wait_for_link() API

Manivannan Sadhasivam via B4 Relay posted 5 patches 2 weeks, 5 days ago
.../pci/controller/dwc/pcie-designware-debugfs.c   | 54 +-------------
drivers/pci/controller/dwc/pcie-designware-host.c  |  9 ++-
drivers/pci/controller/dwc/pcie-designware.c       | 86 +++++++++++++++++++++-
drivers/pci/controller/dwc/pcie-designware.h       |  2 +
4 files changed, 94 insertions(+), 57 deletions(-)
[PATCH v4 0/5] PCI: dwc: Rework the error handling of dw_pcie_wait_for_link() API
Posted by Manivannan Sadhasivam via B4 Relay 2 weeks, 5 days ago
Hi,

This series reworks the dw_pcie_wait_for_link() API to allow the callers to
detect the absence of the device on the bus and skip the failure.

Compared to v2, I've reworked the patch 2 to improve the API further and
dropped the patch 1 that got applied (hence changed the subject). I've also
modified the error code based on the feedback in v2 to return -ENODEV if device
is not detected on the bus, -EIO if the device is found but not active and
-ETIMEDOUT otherwise. This allows the callers to skip the failure as needed.

Testing
=======

Tested this series on Rb3Gen2 board without powering on the PCIe switch. Now the
dw_pcie_wait_for_link() API prints:

	qcom-pcie 1c08000.pcie: Device not found

Instead of the previous log:

	qcom-pcie 1c08000.pcie: Phy link never came up

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
---
Changes in v4:
- Added a check for POLL state and returned -EIO from dw_pcie_wait_for_link()
- Collected tags
- Link to v3: https://lore.kernel.org/r/20251230-pci-dwc-suspend-rework-v3-0-40cd485714f5@oss.qualcomm.com

Changes in v3:
- Dropped patch 1 that got appplied
- Reworked the error handling of dw_pcie_wait_for_link() API further
- Link to v2: https://lore.kernel.org/r/20251218-pci-dwc-suspend-rework-v2-0-5a7778c6094a@oss.qualcomm.com

Changes in v2:
- Changed the logic to check for Detect.Quiet/Active states
- Collected tags and rebased on top of v6.19-rc1
- Link to v1: https://lore.kernel.org/r/20251119-pci-dwc-suspend-rework-v1-0-aad104828562@oss.qualcomm.com

---
Manivannan Sadhasivam (5):
      PCI: dwc: Return -ENODEV from dw_pcie_wait_for_link() if device is not found
      PCI: dwc: Return -EIO from dw_pcie_wait_for_link() if device is not active
      PCI: dwc: Rename and move ltssm_status_string() to pcie-designware.c
      PCI: dwc: Rework the error print of dw_pcie_wait_for_link()
      PCI: dwc: Fail dw_pcie_host_init() if dw_pcie_wait_for_link() returns -ETIMEDOUT

 .../pci/controller/dwc/pcie-designware-debugfs.c   | 54 +-------------
 drivers/pci/controller/dwc/pcie-designware-host.c  |  9 ++-
 drivers/pci/controller/dwc/pcie-designware.c       | 86 +++++++++++++++++++++-
 drivers/pci/controller/dwc/pcie-designware.h       |  2 +
 4 files changed, 94 insertions(+), 57 deletions(-)
---
base-commit: 68ac85fb42cfeb081cf029acdd8aace55ed375a2
change-id: 20251119-pci-dwc-suspend-rework-8b0515a38679

Best regards,
-- 
Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
Re: [PATCH v4 0/5] PCI: dwc: Rework the error handling of dw_pcie_wait_for_link() API
Posted by Manivannan Sadhasivam 2 weeks, 4 days ago
On Tue, 20 Jan 2026 23:17:39 +0530, Manivannan Sadhasivam wrote:
> This series reworks the dw_pcie_wait_for_link() API to allow the callers to
> detect the absence of the device on the bus and skip the failure.
> 
> Compared to v2, I've reworked the patch 2 to improve the API further and
> dropped the patch 1 that got applied (hence changed the subject). I've also
> modified the error code based on the feedback in v2 to return -ENODEV if device
> is not detected on the bus, -EIO if the device is found but not active and
> -ETIMEDOUT otherwise. This allows the callers to skip the failure as needed.
> 
> [...]

Applied, thanks!

[1/5] PCI: dwc: Return -ENODEV from dw_pcie_wait_for_link() if device is not found
      commit: 1bcf245c837bc66fdaddea222bab9eb5c978a9d7
[2/5] PCI: dwc: Return -EIO from dw_pcie_wait_for_link() if device is not active
      commit: 01d16b8afb7afcc17f999f8b4a9b9cfe6c6fae71
[3/5] PCI: dwc: Rename and move ltssm_status_string() to pcie-designware.c
      commit: 36dd677f7d76ddec96d50cf57f543ba7d612087c
[4/5] PCI: dwc: Rework the error print of dw_pcie_wait_for_link()
      commit: d266f63b385a3bad5fd6f23797b6de57de998677
[5/5] PCI: dwc: Fail dw_pcie_host_init() if dw_pcie_wait_for_link() returns -ETIMEDOUT
      commit: 86cbb7a81068434fdc1d5afb96d91ab971fb279e

Best regards,
-- 
Manivannan Sadhasivam <mani@kernel.org>