[PATCH v4 6/7] PCI: mediatek-gen3: Disable device if further setup fails

[Chen-Yu Tsai <wenst@chromium.org>]

If further setup fails after the device is powered on and link training
succeeds, we want to place the device back in a quiescence state to
avoid unintended activity and save power. This also helps with power
state tracking and balancing once pwrctrl API is integrated.

Power down the device in the error paths of mtk_pcie_startup_port() and
mtk_pcie_probe().

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
---
Changes since v3:
- Adapted to movement of existing setup code
  - Cleanup in mtk_pcie_setup() moved to mtk_pcie_probe()
---
 drivers/pci/controller/pcie-mediatek-gen3.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
index 3e5386c4cb35..f1a70b92cc9f 100644
--- a/drivers/pci/controller/pcie-mediatek-gen3.c
+++ b/drivers/pci/controller/pcie-mediatek-gen3.c
@@ -556,10 +556,14 @@ static int mtk_pcie_startup_port(struct mtk_gen3_pcie *pcie)
 		dev_err(pcie->dev,
 			"PCIe link down, current LTSSM state: %s (%#x)\n",
 			ltssm_state, val);
-		return err;
+		goto err_power_down_device;
 	}
 
 	return 0;
+
+err_power_down_device:
+	mtk_pcie_device_power_down(pcie);
+	return err;
 }
 
 #define MTK_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
@@ -1219,6 +1223,7 @@ static int mtk_pcie_probe(struct platform_device *pdev)
 	return 0;
 
 err_power_down_pcie:
+	mtk_pcie_device_power_down(pcie);
 	mtk_pcie_power_down(pcie);
 err_tear_down_irq:
 	mtk_pcie_irq_teardown(pcie);
-- 
2.53.0.473.g4a7958ca14-goog