Date: Wed, 27 Apr 2016 14:46:49 +0800
From: Jisheng Zhang <jszhang@marvell.com>
To: Felipe Balbi <felipe.balbi@linux.intel.com>,
        <mathias.nyman@linux.intel.com>,
        Kishon Vijay Abraham I <kishon@ti.com>,
        <thomas.petazzoni@free-electrons.com>,
        <gregory.clement@free-electrons.com>,
        <maxime.ripard@free-electrons.com>
CC: <gregkh@linuxfoundation.org>, <linux-usb@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-arm-kernel@lists.infradead.org>,
        <yendapally.reddy@broadcom.com>
Subject: Re: [RESEND PATCH v2 6/7] usb: xhci: plat: add generic PHY support
Message-ID: <20160427144649.67304003@xhacker>
In-Reply-To: <87eg9rpq9t.fsf@intel.com>
References: <1461675460-2295-1-git-send-email-jszhang@marvell.com>
	<1461675460-2295-7-git-send-email-jszhang@marvell.com>
	<87eg9rpq9t.fsf@intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 5891
Lines: 202

Dear Felipe,

On Wed, 27 Apr 2016 08:35:58 +0300 Felipe Balbi wrote:

> Hi,
> 
> Jisheng Zhang <jszhang@marvell.com> writes:
> > Marvell BG4CT SoC needs two phy: one for usb2 and another for usb3. Add
> > the calls to retrieve generic PHY to xhci plat in order to support this.
> >
> > Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
> > ---
> >  drivers/usb/host/xhci-plat.c | 87 ++++++++++++++++++++++++++++++++++++++------
> >  1 file changed, 75 insertions(+), 12 deletions(-)
> >
> > diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
> > index 83669d0..d7f4f3c 100644
> > --- a/drivers/usb/host/xhci-plat.c
> > +++ b/drivers/usb/host/xhci-plat.c
> > @@ -16,6 +16,7 @@
> >  #include <linux/dma-mapping.h>
> >  #include <linux/module.h>
> >  #include <linux/of.h>
> > +#include <linux/phy/phy.h>
> >  #include <linux/platform_device.h>
> >  #include <linux/slab.h>
> >  #include <linux/usb/phy.h>
> > @@ -134,6 +135,37 @@ static const struct of_device_id usb_xhci_of_match[] = {
> >  MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
> >  #endif
> >  
> > +static int xhci_plat_phy_init(struct usb_hcd *hcd)
> > +{
> > +	int ret;
> > +
> > +	if (hcd->phy) {
> > +		ret = phy_init(hcd->phy);
> > +		if (ret)
> > +			return ret;
> > +
> > +		ret = phy_power_on(hcd->phy);
> > +		if (ret) {
> > +			phy_exit(hcd->phy);
> > +			return ret;
> > +		}
> > +	} else {
> > +		ret = usb_phy_init(hcd->usb_phy);
> > +	}
> > +
> > +	return ret;
> > +}
> > +
> > +static void xhci_plat_phy_exit(struct usb_hcd *hcd)
> > +{
> > +	if (hcd->phy) {
> > +		phy_power_off(hcd->phy);
> > +		phy_exit(hcd->phy);
> > +	} else {
> > +		usb_phy_shutdown(hcd->usb_phy);
> > +	}
> > +}
> > +
> >  static int xhci_plat_probe(struct platform_device *pdev)
> >  {
> >  	struct device_node	*node = pdev->dev.of_node;
> > @@ -145,6 +177,7 @@ static int xhci_plat_probe(struct platform_device *pdev)
> >  	struct usb_hcd		*hcd;
> >  	struct clk              *clk;
> >  	struct usb_phy		*usb_phy;
> > +	struct phy		*phy;  
> 
> so, one phy driver using USB PHY layer and another using generic PHY
> layer ? Why ? I think the first thing your series should do would be to

It's different platforms. E.g
platform A may write the phy driver under usb phy layer, while platform B
may have generic phy driver.

The questions are: when adding phy support to xhci-plat, the generic phy
has existed for a long time, what's the reason to use the deprecated usb
phy APIs.

And per my check, it's only MVEBU platforms use this support? I'm not sure
if we could remove usbphy code from xhci-plat first then add generic phy then
adding MVEBU xhci phy support bak with the new code. So Cc mvebu maintainers

Thanks,
Jisheng

> add proper suport for both APIs with two PHYs and make them all optional
> for xhci-plat.
> 
> > @@ -232,22 +265,44 @@ static int xhci_plat_probe(struct platform_device *pdev)
> >  	if (HCC_MAX_PSA(xhci->hcc_params) >= 4)
> >  		xhci->shared_hcd->can_do_streams = 1;
> >  
> > +	hcd->phy = devm_phy_get(&pdev->dev, "usb2-phy");
> > +	if (IS_ERR(hcd->phy)) {
> > +		ret = PTR_ERR(hcd->phy);
> > +		if (ret == -EPROBE_DEFER)
> > +			goto put_usb3_hcd;
> > +		hcd->phy = NULL;
> > +	}
> > +
> > +	phy = devm_phy_get(&pdev->dev, "usb-phy");
> > +	if (IS_ERR(phy)) {
> > +		ret = PTR_ERR(phy);
> > +		if (ret == -EPROBE_DEFER)
> > +			goto put_usb3_hcd;
> > +		phy = NULL;
> > +	}
> > +
> >  	usb_phy = devm_usb_get_phy_by_phandle(&pdev->dev, "usb-phy", 0);
> >  	if (IS_ERR(usb_phy)) {
> >  		ret = PTR_ERR(usb_phy);
> >  		if (ret == -EPROBE_DEFER)
> >  			goto put_usb3_hcd;
> >  		usb_phy = NULL;
> > -	} else {
> > -		ret = usb_phy_init(usb_phy);
> > -		if (ret)
> > -			goto put_usb3_hcd;
> >  	}
> > +
> >  	xhci->shared_hcd->usb_phy = usb_phy;
> > +	xhci->shared_hcd->phy = phy;
> > +
> > +	ret = xhci_plat_phy_init(hcd);
> > +	if (ret)
> > +		goto put_usb3_hcd;
> > +
> > +	ret = xhci_plat_phy_init(xhci->shared_hcd);
> > +	if (ret)
> > +		goto disable_usb2_phy;
> >  
> >  	ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
> >  	if (ret)
> > -		goto disable_usb_phy;
> > +		goto disable_usb3_phy;
> >  
> >  	ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
> >  	if (ret)
> > @@ -259,8 +314,11 @@ static int xhci_plat_probe(struct platform_device *pdev)
> >  dealloc_usb2_hcd:
> >  	usb_remove_hcd(hcd);
> >  
> > -disable_usb_phy:
> > -	usb_phy_shutdown(usb_phy);
> > +disable_usb3_phy:
> > +	xhci_plat_phy_exit(xhci->shared_hcd);
> > +
> > +disable_usb2_phy:
> > +	xhci_plat_phy_exit(hcd);
> >  
> >  put_usb3_hcd:
> >  	usb_put_hcd(xhci->shared_hcd);
> > @@ -281,11 +339,11 @@ static int xhci_plat_remove(struct platform_device *dev)
> >  	struct clk *clk = xhci->clk;
> >  
> >  	usb_remove_hcd(xhci->shared_hcd);
> > -	usb_phy_shutdown(xhci->shared_hcd->usb_phy);
> > -
> > -	usb_remove_hcd(hcd);
> > +	xhci_plat_phy_exit(xhci->shared_hcd);
> >  	usb_put_hcd(xhci->shared_hcd);
> >  
> > +	usb_remove_hcd(hcd);
> > +	xhci_plat_phy_exit(hcd);
> >  	clk_disable_unprepare(clk);
> >  	usb_put_hcd(hcd);
> >  
> > @@ -311,7 +369,8 @@ static int xhci_plat_suspend(struct device *dev)
> >  	if (ret)
> >  		return ret;
> >  
> > -	usb_phy_shutdown(xhci->shared_hcd->usb_phy);
> > +	xhci_plat_phy_exit(xhci->shared_hcd);
> > +	xhci_plat_phy_exit(hcd);
> >  	clk_disable_unprepare(xhci->clk);
> >  
> >  	return ret;
> > @@ -327,7 +386,11 @@ static int xhci_plat_resume(struct device *dev)
> >  	if (ret)
> >  		return ret;
> >  
> > -	ret = usb_phy_init(xhci->shared_hcd->usb_phy);
> > +	ret = xhci_plat_phy_init(hcd);
> > +	if (ret)
> > +		return ret;
> > +
> > +	ret = xhci_plat_phy_init(xhci->shared_hcd);
> >  	if (ret)
> >  		return ret;
> >  
> > -- 
> > 2.8.1
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-usb" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html  
>