Re: [PATCH 07/15] PCI: brcmstb: Add control of rescal reset
From: Philipp Zabel <hidden>
Date: 2020-05-20 07:28:11
Also in:
linux-pci, lkml
Hi Jim, On Tue, May 19, 2020 at 04:34:05PM -0400, Jim Quinlan wrote:
quoted hunk ↗ jump to hunk
From: Jim Quinlan <redacted> Some STB chips have a special purpose reset controller named RESCAL (reset calibration). This commit adds the control of RESCAL as well as the ability to start and stop its operation for PCIe HW. Signed-off-by: Jim Quinlan <redacted> --- drivers/pci/controller/pcie-brcmstb.c | 81 ++++++++++++++++++++++++++- 1 file changed, 80 insertions(+), 1 deletion(-)diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c index 2c470104ba38..0787e8f6f7e5 100644 --- a/drivers/pci/controller/pcie-brcmstb.c +++ b/drivers/pci/controller/pcie-brcmstb.c
[...]
quoted hunk ↗ jump to hunk
@@ -1100,6 +1164,21 @@ static int brcm_pcie_probe(struct platform_device *pdev) dev_err(&pdev->dev, "could not enable clock\n"); return ret; } + pcie->rescal = devm_reset_control_get_shared(&pdev->dev, "rescal"); + if (IS_ERR(pcie->rescal)) { + if (PTR_ERR(pcie->rescal) == -EPROBE_DEFER) + return -EPROBE_DEFER; + pcie->rescal = NULL;
This is effectively an optional reset control, so it is better to use: ↵ pcie->rescal = devm_reset_control_get_optional_shared(&pdev->dev, "rescal");↵ if (IS_ERR(pcie->rescal)) return PTR_ERR(pcie->rescal);
+ } else {
+ ret = reset_control_deassert(pcie->rescal);
+ if (ret)
+ dev_err(&pdev->dev, "failed to deassert 'rescal'\n");
+ }reset_control_* can handle rstc == NULL parameters for optional reset controls, so this can be done unconditionally: ret = reset_control_deassert(pcie->rescal);↵ if (ret)↵ dev_err(&pdev->dev, "failed to deassert 'rescal'\n");↵ Is rescal handled by the reset-brcmstb-rescal driver? Since that only implements the .reset op, I would expect reset_control_reset() here. Otherwise this looks like it'd be missing a reset_control_assert in remove. regards Philipp _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel