提交 d9e8a7a7 编写于 作者: B Bjorn Andersson 提交者: Xie XiuQi

PCI: qcom: Don't deassert reset GPIO during probe

[ Upstream commit 02b485e31d98265189b91f3e69c43df2ed50610c ]

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: 82a82383 ("PCI: qcom: Add Qualcomm PCIe controller driver")
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: NStanimir Varbanov <svarbanov@mm-sol.com>
Cc: stable@vger.kernel.org
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
上级 d407b6c4
......@@ -1230,7 +1230,7 @@ static int qcom_pcie_probe(struct platform_device *pdev)
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;
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册