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PCI: brcmstb: Use reset/rearm instead of deassert/assert

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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: 740d6c3708 ("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>
This commit is contained in:
Jim Quinlan 2021-04-30 11:21:56 -04:00 committed by Bjorn Helgaas
parent e8d6f9e561
commit bb610757fc
1 changed files with 13 additions and 6 deletions
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19
drivers/pci/controller/pcie-brcmstb.c
View file

@ -1148,6 +1148,7 @@ 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;
@ -1163,9 +1164,13 @@ 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);
@ -1180,14 +1185,16 @@ 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;
}
@ -1197,7 +1204,7 @@ 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);
}
@ -1278,13 +1285,13 @@ static int brcm_pcie_probe(struct platform_device *pdev)
return PTR_ERR(pcie->perst_reset);
}
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;
}