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

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>

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index e330e6811f0b6ab8281767b16da2896cd81ee085..3b35d629035ec9e455a88c1398f223e77b5854d6 100644 (file)
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -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;
        }