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    Subject[PATCH 5.0 129/238] PCI: qcom: Dont deassert reset GPIO during probe
    Date
    5.0-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Bjorn Andersson <bjorn.andersson@linaro.org>

    commit 02b485e31d98265189b91f3e69c43df2ed50610c upstream.

    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
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    drivers/pci/controller/dwc/pcie-qcom.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    --- a/drivers/pci/controller/dwc/pcie-qcom.c
    +++ b/drivers/pci/controller/dwc/pcie-qcom.c
    @@ -1228,7 +1228,7 @@ static int qcom_pcie_probe(struct platfo

    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)) {
    ret = PTR_ERR(pcie->reset);
    goto err_pm_runtime_put;

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