RE: [PATCH v7 6/8] PCI: dwc: Add dw_pcie_host_ops.host_exit() callback

From: Hongxing Zhu <hongxing.zhu@nxp.com>
To: Bjorn Helgaas <helgaas@kernel.org>
Cc: "l.stach@pengutronix.de" <l.stach@pengutronix.de>,
	"bhelgaas@google.com" <bhelgaas@google.com>,
	"broonie@kernel.org" <broonie@kernel.org>,
	"lorenzo.pieralisi@arm.com" <lorenzo.pieralisi@arm.com>,
	"jingoohan1@gmail.com" <jingoohan1@gmail.com>,
	"festevam@gmail.com" <festevam@gmail.com>,
	"francesco.dolcini@toradex.com" <francesco.dolcini@toradex.com>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"kernel@pengutronix.de" <kernel@pengutronix.de>,
	dl-linux-imx <linux-imx@nxp.com>
Subject: RE: [PATCH v7 6/8] PCI: dwc: Add dw_pcie_host_ops.host_exit() callback
Date: Thu, 24 Feb 2022 07:50:25 +0000	[thread overview]
Message-ID: <AS8PR04MB8676315428521976BD804D858C3D9@AS8PR04MB8676.eurprd04.prod.outlook.com> (raw)
In-Reply-To: <20220223174940.GA140379@bhelgaas>

> -----Original Message-----
> From: Bjorn Helgaas <helgaas@kernel.org>
> Sent: 2022年2月24日 1:50
> To: Hongxing 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; dl-linux-imx <linux-imx@nxp.com>
> Subject: Re: [PATCH v7 6/8] PCI: dwc: Add dw_pcie_host_ops.host_exit()
> callback
> 
> 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.

Thanks, it's more detailed, and easier understand. Would be updated later.

Best Regards
Richard Zhu