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Date:   Wed, 23 Feb 2022 11:49:40 -0600
From:   Bjorn Helgaas <helgaas@kernel.org>
To:     Richard Zhu <hongxing.zhu@nxp.com>
Cc:     l.stach@pengutronix.de, bhelgaas@google.com, broonie@kernel.org,
        lorenzo.pieralisi@arm.com, jingoohan1@gmail.com,
        festevam@gmail.com, francesco.dolcini@toradex.com,
        linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, kernel@pengutronix.de,
        linux-imx@nxp.com
Subject: Re: [PATCH v7 6/8] PCI: dwc: Add dw_pcie_host_ops.host_exit()
 callback
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On Wed, Feb 16, 2022 at 02:21:01PM +0800, Richard Zhu wrote:
> When link is never came up in the link training after host_init.
> The clocks and power supplies usage counter balance should be handled
> properly on some DWC platforms (for example, i.MX PCIe).
>
> Add a new host_exit() callback into dw_pcie_host_ops, then it could be
> invoked to handle the unbalance issue in the error handling after
> host_init() function when link is down.

Possible rewording, not sure if it captures everything you want:

  When the link never comes up after ->host_init(), some drivers,
  especially those that don't support hotplug, want to turn off clocks
  and power supplies.

  Add a new ->host_exit() callback in dw_pcie_host_ops so these
  drivers can clean up if ->host_init() fails.