[PATCH v3 11/13] PCI: dwc-plat: Simplify the probe method return value handling

From: Serge Semin <Sergey.Semin@baikalelectronics.ru>
To: "Jingoo Han" <jingoohan1@gmail.com>,
	"Gustavo Pimentel" <gustavo.pimentel@synopsys.com>,
	"Bjorn Helgaas" <bhelgaas@google.com>,
	"Lorenzo Pieralisi" <lorenzo.pieralisi@arm.com>,
	"Rob Herring" <robh@kernel.org>,
	"Krzysztof Wilczyński" <kw@linux.com>
Cc: Serge Semin <Sergey.Semin@baikalelectronics.ru>,
	Serge Semin <fancer.lancer@gmail.com>,
	Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>,
	Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>,
	Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>,
	Frank Li <Frank.Li@nxp.com>, <linux-pci@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>
Subject: [PATCH v3 11/13] PCI: dwc-plat: Simplify the probe method return value handling
Date: Tue, 17 May 2022 15:50:56 +0300	[thread overview]
Message-ID: <20220517125058.18488-12-Sergey.Semin@baikalelectronics.ru> (raw)
In-Reply-To: <20220517125058.18488-1-Sergey.Semin@baikalelectronics.ru>

The whole switch-case-logic implemented in the DWC PCIe RC/EP probe
procedure doesn't seem well thought through. First of all the ret variable
is unused in the EP-case and is only partly involved in the RC-case of the
switch-case statement, which unnecessary complicates the code. Secondly
the probe method will return zero if an unknown mode is detected. That is
improbable situation since the OF-device data is initialized only with
valid modes, but such code is still wrong at least from maintainability
point of view. So let's convert the switch-case part of the probe function
to being more coherent. We suggest to use the local ret variable to
preserve the status of the case-clauses and return its value from the
probe procedure after the work is done.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/controller/dwc/pcie-designware-plat.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-plat.c b/drivers/pci/controller/dwc/pcie-designware-plat.c
index 0c5de87d3cc6..fea785096261 100644
--- a/drivers/pci/controller/dwc/pcie-designware-plat.c
+++ b/drivers/pci/controller/dwc/pcie-designware-plat.c
@@ -153,20 +153,21 @@ static int dw_plat_pcie_probe(struct platform_device *pdev)
 			return -ENODEV;
 
 		ret = dw_plat_add_pcie_port(dw_plat_pcie, pdev);
-		if (ret < 0)
-			return ret;
 		break;
 	case DW_PCIE_EP_TYPE:
 		if (!IS_ENABLED(CONFIG_PCIE_DW_PLAT_EP))
 			return -ENODEV;
 
 		pci->ep.ops = &pcie_ep_ops;
-		return dw_pcie_ep_init(&pci->ep);
+		ret = dw_pcie_ep_init(&pci->ep);
+		break;
 	default:
 		dev_err(dev, "INVALID device type %d\n", dw_plat_pcie->mode);
+		ret = -EINVAL;
+		break;
 	}
 
-	return 0;
+	return ret;
 }
 
 static const struct dw_plat_pcie_of_data dw_plat_pcie_rc_of_data = {
-- 
2.35.1

