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Subject[PATCH 5.11 191/329] PCI: brcmstb: Use reset/rearm instead of deassert/assert
Date
From: Jim Quinlan <jim2101024@gmail.com>

[ Upstream commit bb610757fcd74558ad94fe19993fd4470208dd02 ]

The Broadcom STB PCIe RC uses a reset control "rescal" for certain chips.
The "rescal" implements a "pulse reset" so using assert/deassert is wrong
for this device. Instead, we use reset/rearm. We need to use rearm so
that we can reset it after a suspend/resume cycle; w/o using "rearm", the
"rescal" device will only ever fire once.

Of course for suspend/resume to work we also need to put the reset/rearm
calls in the suspend and resume routines.

Fixes: 740d6c3708a9 ("PCI: brcmstb: Add control of rescal reset")
Link: https://lore.kernel.org/r/20210430152156.21162-4-jim2101024@gmail.com
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pci/controller/pcie-brcmstb.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index d41257f43a8f..7cbd56d8a5ff 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -1127,6 +1127,7 @@ static int brcm_pcie_suspend(struct device *dev)

brcm_pcie_turn_off(pcie);
ret = brcm_phy_stop(pcie);
+ reset_control_rearm(pcie->rescal);
clk_disable_unprepare(pcie->clk);

return ret;
@@ -1142,9 +1143,13 @@ static int brcm_pcie_resume(struct device *dev)
base = pcie->base;
clk_prepare_enable(pcie->clk);

+ ret = reset_control_reset(pcie->rescal);
+ if (ret)
+ goto err_disable_clk;
+
ret = brcm_phy_start(pcie);
if (ret)
- goto err;
+ goto err_reset;

/* Take bridge out of reset so we can access the SERDES reg */
pcie->bridge_sw_init_set(pcie, 0);
@@ -1159,14 +1164,16 @@ static int brcm_pcie_resume(struct device *dev)

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

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

return 0;

-err:
+err_reset:
+ reset_control_rearm(pcie->rescal);
+err_disable_clk:
clk_disable_unprepare(pcie->clk);
return ret;
}
@@ -1176,7 +1183,7 @@ static void __brcm_pcie_remove(struct brcm_pcie *pcie)
brcm_msi_remove(pcie);
brcm_pcie_turn_off(pcie);
brcm_phy_stop(pcie);
- reset_control_assert(pcie->rescal);
+ reset_control_rearm(pcie->rescal);
clk_disable_unprepare(pcie->clk);
}

@@ -1251,13 +1258,13 @@ static int brcm_pcie_probe(struct platform_device *pdev)
return PTR_ERR(pcie->rescal);
}

- ret = reset_control_deassert(pcie->rescal);
+ ret = reset_control_reset(pcie->rescal);
if (ret)
dev_err(&pdev->dev, "failed to deassert 'rescal'\n");

ret = brcm_phy_start(pcie);
if (ret) {
- reset_control_assert(pcie->rescal);
+ reset_control_rearm(pcie->rescal);
clk_disable_unprepare(pcie->clk);
return ret;
}
--
2.30.2


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