Re: [PATCH v2 5/7] usb: cdns3: add quirk to platform data for reset-on-resume

From: Peter Chen <peter.chen@kernel.org>
To: "Théo Lebrun" <theo.lebrun@bootlin.com>
Cc: "Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
	"Rob Herring" <robh+dt@kernel.org>,
	"Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
	"Conor Dooley" <conor+dt@kernel.org>,
	"Roger Quadros" <rogerq@kernel.org>,
	"Pawel Laszczak" <pawell@cadence.com>,
	"Nishanth Menon" <nm@ti.com>,
	"Vignesh Raghavendra" <vigneshr@ti.com>,
	"Tero Kristo" <kristo@kernel.org>,
	linux-usb@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	ThomasPetazzonithomas.petazzoni@bootlin.com,
	"Grégory Clement" <gregory.clement@bootlin.com>
Subject: Re: [PATCH v2 5/7] usb: cdns3: add quirk to platform data for reset-on-resume
Date: Tue, 21 Nov 2023 18:40:56 +0800	[thread overview]
Message-ID: <20231121104056.GA541474@nchen-desktop> (raw)
In-Reply-To: <20231120-j7200-usb-suspend-v2-5-038c7e4a3df4@bootlin.com>

On 23-11-20 18:06:05, Théo Lebrun wrote:
> The cdns3 host role does not care about reset-on-resume. xHCI however
> reconfigures itself in silence rather than printing a warning about a
> resume error. Related warning example:
> 
>   [   16.017462] xhci-hcd xhci-hcd.1.auto: xHC error in resume, USBSTS 0x401, Reinit
> 
> Allow passing a CDNS3_RESET_ON_RESUME quirk flag from cdns3 pdata down
> to xHCI pdata. The goal is to allow signaling about reset-on-resume
> behavior from platform wrapper drivers.
> 
> When used, remote wakeup is not expected to work.
> 
> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>

Acked-by: Peter Chen <peter.chen@kernel.org>

> ---
>  drivers/usb/cdns3/core.h | 1 +
>  drivers/usb/cdns3/host.c | 3 +++
>  2 files changed, 4 insertions(+)
> 
> diff --git a/drivers/usb/cdns3/core.h b/drivers/usb/cdns3/core.h
> index 81a9c9d6be08..7487067ba23f 100644
> --- a/drivers/usb/cdns3/core.h
> +++ b/drivers/usb/cdns3/core.h
> @@ -44,6 +44,7 @@ struct cdns3_platform_data {
>  			bool suspend, bool wakeup);
>  	unsigned long quirks;
>  #define CDNS3_DEFAULT_PM_RUNTIME_ALLOW	BIT(0)
> +#define CDNS3_RESET_ON_RESUME		BIT(1)
>  };
>  
>  /**
> diff --git a/drivers/usb/cdns3/host.c b/drivers/usb/cdns3/host.c
> index 6164fc4c96a4..28c4d1deb231 100644
> --- a/drivers/usb/cdns3/host.c
> +++ b/drivers/usb/cdns3/host.c
> @@ -91,6 +91,9 @@ static int __cdns_host_init(struct cdns *cdns)
>  	if (cdns->pdata && (cdns->pdata->quirks & CDNS3_DEFAULT_PM_RUNTIME_ALLOW))
>  		cdns->xhci_plat_data->quirks |= XHCI_DEFAULT_PM_RUNTIME_ALLOW;
>  
> +	if (cdns->pdata && (cdns->pdata->quirks & CDNS3_RESET_ON_RESUME))
> +		cdns->xhci_plat_data->quirks |= XHCI_RESET_ON_RESUME;
> +
>  	ret = platform_device_add_data(xhci, cdns->xhci_plat_data,
>  			sizeof(struct xhci_plat_priv));
>  	if (ret)
> 
> -- 
> 2.42.0
> 

-- 

Thanks,
Peter Chen