From: Bjorn Andersson <bjorn.andersson@linaro.org>
Date: Fri, 25 Jan 2019 15:26:16 -0800
Subject: PCI: qcom: Don't deassert reset GPIO during probe
Git-commit: 02b485e31d98265189b91f3e69c43df2ed50610c
Patch-mainline: v5.1-rc1
References: bsc#1129281
Acquiring the reset GPIO low means that reset is being deasserted, this
is followed almost immediately with qcom_pcie_host_init() asserting it,
initializing it and then finally deasserting it again, for the link to
come up.
Some PCIe devices requires a minimum time between the initial deassert
and subsequent reset cycles. In a platform that boots with the reset
GPIO asserted this requirement is being violated by this deassert/assert
pulse.
Acquire the reset GPIO high to prevent this situation by matching the
state to the subsequent asserted state.
Fixes: 82a823833f4e ("PCI: qcom: Add Qualcomm PCIe controller driver")
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Stanimir Varbanov <svarbanov@mm-sol.com>
Cc: stable@vger.kernel.org
Acked-by: Joerg Roedel <jroedel@suse.de>
---
drivers/pci/controller/dwc/pcie-qcom.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/pci/dwc/pcie-qcom.c
+++ b/drivers/pci/dwc/pcie-qcom.c
@@ -690,7 +690,7 @@ static int qcom_pcie_probe(struct platfo
pcie->ops = (struct qcom_pcie_ops *)of_device_get_match_data(dev);
- pcie->reset = devm_gpiod_get_optional(dev, "perst", GPIOD_OUT_LOW);
+ pcie->reset = devm_gpiod_get_optional(dev, "perst", GPIOD_OUT_HIGH);
if (IS_ERR(pcie->reset))
return PTR_ERR(pcie->reset);