[PATCH v2] PCI: brcmstb: Add missing if statement and error path

From: Alex Dewar
Date: Mon Sep 21 2020 - 17:19:27 EST


brcm_pcie_resume() contains a return statement that was presumably
intended to have an "if (ret)" in front of it, otherwise the function
returns prematurely. Fix this.

Additionally, redisable the clock on the error path.

I don't know if this code was tested or not, but I assume that this bug
means that this driver will not resume properly.

Fixes: ad3d29c77e1e ("PCI: brcmstb: Add control of rescal reset")
Addresses-Coverity: CID 1497099: Control flow issues (UNREACHABLE)
Signed-off-by: Alex Dewar <alex.dewar90@xxxxxxxxx>
---
Hi Jim,

Here's a new version of the patch.

I added the missing clk_disable_unprepare() and assumed that it would
also be required in the case that the call to brcm_pcie_setup() fails.

I didn't follow the suggestion of adding extra braces to the
if-statement as the kernel style is not to add unnecessary braces in
this case: https://www.kernel.org/doc/html/latest/process/coding-style.html?highlight=style#placing-braces-and-spaces

Best,
Alex

drivers/pci/controller/pcie-brcmstb.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index 7a3ff4632e7c..8bae3a4f8e49 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -1154,7 +1154,8 @@ static int brcm_pcie_resume(struct device *dev)
clk_prepare_enable(pcie->clk);

ret = brcm_phy_start(pcie);
- return ret;
+ if (ret)
+ goto err;

/* Take bridge out of reset so we can access the SERDES reg */
pcie->bridge_sw_init_set(pcie, 0);
@@ -1169,12 +1170,16 @@ static int brcm_pcie_resume(struct device *dev)

ret = brcm_pcie_setup(pcie);
if (ret)
- return ret;
+ goto err;

if (pcie->msi)
brcm_msi_set_regs(pcie->msi);

return 0;
+
+err:
+ clk_disable_unprepare(pcie->clk);
+ return ret;
}

static void __brcm_pcie_remove(struct brcm_pcie *pcie)
--
2.28.0