Re: [PATCH v3 03/10] usb: ehci-orion: avoid double PHY initialization

From: Alan Stern <stern@rowland.harvard.edu>
To: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Mark Rutland <mark.rutland@arm.com>, Andrew Lunn <andrew@lunn.ch>,
	Jason Cooper <jason@lakedaemon.net>,
	Mathias Nyman <mathias.nyman@intel.com>,
	devicetree@vger.kernel.org,
	Antoine Tenart <antoine.tenart@bootlin.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Gregory Clement <gregory.clement@bootlin.com>,
	linux-usb@vger.kernel.org, Kishon Vijay Abraham I <kishon@ti.com>,
	Nadav Haklai <nadavh@marvell.com>,
	Rob Herring <robh+dt@kernel.org>,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
	Maxime Chevallier <maxime.chevallier@bootlin.com>,
	linux-arm-kernel@lists.infradead.org,
	Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Subject: Re: [PATCH v3 03/10] usb: ehci-orion: avoid double PHY initialization
Date: Wed, 23 Jan 2019 15:01:56 -0500 (EST)	[thread overview]
Message-ID: <Pine.LNX.4.44L0.1901231500300.1564-100000@iolanthe.rowland.org> (raw)
In-Reply-To: <20190121112336.23489-4-miquel.raynal@bootlin.com>

On Mon, 21 Jan 2019, Miquel Raynal wrote:

> No need to initialize the PHY from the driver's probe. It is done by
> the core automatically and doing it twice would increment the
> phy->powercount counter to 2 instead of 1. During later suspend
> operation, the counter will be decremented to one, no phy->power_off()
> will occur and worse than that, the following phy->power_on() at
> resume time will also be skipped, failing the whole S2RAM operation.
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> ---

Acked-by: Alan Stern <stern@rowland.harvard.edu>

>  drivers/usb/host/ehci-orion.c | 26 +++-----------------------
>  1 file changed, 3 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/usb/host/ehci-orion.c b/drivers/usb/host/ehci-orion.c
> index 1ad72647a069..3109f082949e 100644
> --- a/drivers/usb/host/ehci-orion.c
> +++ b/drivers/usb/host/ehci-orion.c
> @@ -257,15 +257,7 @@ static int ehci_orion_drv_probe(struct platform_device *pdev)
>  	if (IS_ERR(priv->phy)) {
>  		err = PTR_ERR(priv->phy);
>  		if (err != -ENOSYS)
> -			goto err_phy_get;
> -	} else {
> -		err = phy_init(priv->phy);
> -		if (err)
> -			goto err_phy_init;
> -
> -		err = phy_power_on(priv->phy);
> -		if (err)
> -			goto err_phy_power_on;
> +			goto err_dis_clk;
>  	}
>  
>  	/*
> @@ -297,19 +289,12 @@ static int ehci_orion_drv_probe(struct platform_device *pdev)
>  
>  	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
>  	if (err)
> -		goto err_add_hcd;
> +		goto err_dis_clk;
>  
>  	device_wakeup_enable(hcd->self.controller);
>  	return 0;
>  
> -err_add_hcd:
> -	if (!IS_ERR(priv->phy))
> -		phy_power_off(priv->phy);
> -err_phy_power_on:
> -	if (!IS_ERR(priv->phy))
> -		phy_exit(priv->phy);
> -err_phy_init:
> -err_phy_get:
> +err_dis_clk:
>  	if (!IS_ERR(priv->clk))
>  		clk_disable_unprepare(priv->clk);
>  	usb_put_hcd(hcd);
> @@ -327,11 +312,6 @@ static int ehci_orion_drv_remove(struct platform_device *pdev)
>  
>  	usb_remove_hcd(hcd);
>  
> -	if (!IS_ERR(priv->phy)) {
> -		phy_power_off(priv->phy);
> -		phy_exit(priv->phy);
> -	}
> -
>  	if (!IS_ERR(priv->clk))
>  		clk_disable_unprepare(priv->clk);