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 69c999222cc8..08bc788d9422 100644 --- 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; }