From: Phil Edworthy <phil.edworthy@renesas.com>
To: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
CC: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Felipe Balbi <balbi@ti.com>, Ulrich Hecht <ulrich.hecht@gmail.com>,
        Kishon Vijay Abraham I <kishon@ti.com>,
        "Sergei Shtylyov" <sergei.shtylyov@cogentembedded.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
        "linux-sh@vger.kernel.org" <linux-sh@vger.kernel.org>,
        Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Subject: RE: [PATCH v2] usb: renesas_usbhs: Allow an OTG PHY driver to provide
 VBUS
Thread-Topic: [PATCH v2] usb: renesas_usbhs: Allow an OTG PHY driver to
 provide VBUS
Thread-Index: AQHQtJov6QAOeJ5fNUapptyc9faHp53H1TgAgAAB+JA=
Date: Thu, 2 Jul 2015 08:35:48 +0000
Message-ID: <SIXPR06MB06396A96DF4AEAF45837B4CBF5970@SIXPR06MB0639.apcprd06.prod.outlook.com>
References: <1435822602-22685-1-git-send-email-phil.edworthy@renesas.com>
 <2896957.Pcl0CbmdvL@avalon>
In-Reply-To: <2896957.Pcl0CbmdvL@avalon>
Accept-Language: en-GB, en-US
Content-Language: en-US
spamdiagnosticoutput: 1:23
spamdiagnosticmetadata: NSPM
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 8BIT
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-originalarrivaltime: 02 Jul 2015 08:35:48.2466
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 53d82571-da19-47e4-9cb4-625a166a4a2a
X-MS-Exchange-Transport-CrossTenantHeadersStamped: SIXPR06MB0605
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 5882
Lines: 186

Hi Laurent,

On 02 July 2015 09:15, Laurent wrote:
> Hi Phil,
> 
> (CC'ing Morimoto-san)
> 
> Thank you for the patch.
> 
> On Thursday 02 July 2015 08:36:42 Phil Edworthy wrote:
> > These changes allow a PHY driver to trigger a VBUS interrupt and
> > to provide the value of VBUS.
> >
> > Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
> >
> > ---
> > v2:
> >   - vbus variables changed from int to bool.
> >   - dev_info() changed to dev_err()
> > ---
> >  drivers/usb/renesas_usbhs/common.h     |  2 ++
> >  drivers/usb/renesas_usbhs/mod.c        |  3 +++
> >  drivers/usb/renesas_usbhs/mod_gadget.c | 38
> +++++++++++++++++++++++++++++++
> >  3 files changed, 43 insertions(+)
> >
> > diff --git a/drivers/usb/renesas_usbhs/common.h
> > b/drivers/usb/renesas_usbhs/common.h index 8c5fc12..478700c 100644
> > --- a/drivers/usb/renesas_usbhs/common.h
> > +++ b/drivers/usb/renesas_usbhs/common.h
> > @@ -255,6 +255,8 @@ struct usbhs_priv {
> >  	struct renesas_usbhs_driver_param	dparam;
> >
> >  	struct delayed_work notify_hotplug_work;
> > +	bool vbus_is_indirect;
> > +	bool vbus_indirect_value;
> >  	struct platform_device *pdev;
> >
> >  	struct extcon_dev *edev;
> > diff --git a/drivers/usb/renesas_usbhs/mod.c
> > b/drivers/usb/renesas_usbhs/mod.c index 9a705b1..8a2d3dd 100644
> > --- a/drivers/usb/renesas_usbhs/mod.c
> > +++ b/drivers/usb/renesas_usbhs/mod.c
> > @@ -42,6 +42,9 @@ static int usbhsm_autonomy_get_vbus(struct
> platform_device
> > *pdev) {
> >  	struct usbhs_priv *priv = usbhs_pdev_to_priv(pdev);
> >
> > +	if (priv->vbus_is_indirect)
> > +		return priv->vbus_indirect_value;
> > +
> 
> Something is bothering me. The comment block right before this function states
> that "these functions are used if platform doesn't have external phy".
> However, the mechanism you implement here is aimed at letting a PHY control
> vbus. I have a feeling this isn't the right mechanism.

I took the comment as though it was talking about an physically external PHY, but
I suppose it makes no difference from the point of view of this driver. I'll have a
look to see if there is a better way to hook this in.


> >  	return  VBSTS & usbhs_read(priv, INTSTS0);
> >  }
> >
> > diff --git a/drivers/usb/renesas_usbhs/mod_gadget.c
> > b/drivers/usb/renesas_usbhs/mod_gadget.c index dc2aa32..51b63f9 100644
> > --- a/drivers/usb/renesas_usbhs/mod_gadget.c
> > +++ b/drivers/usb/renesas_usbhs/mod_gadget.c
> > @@ -21,6 +21,7 @@
> >  #include <linux/platform_device.h>
> >  #include <linux/usb/ch9.h>
> >  #include <linux/usb/gadget.h>
> > +#include <linux/usb/otg.h>
> >  #include "common.h"
> >
> >  /*
> > @@ -50,6 +51,7 @@ struct usbhsg_gpriv {
> >  	int			 uep_size;
> >
> >  	struct usb_gadget_driver	*driver;
> > +	struct usb_phy		*transceiver;
> >
> >  	u32	status;
> >  #define USBHSG_STATUS_STARTED		(1 << 0)
> > @@ -882,6 +884,8 @@ static int usbhsg_gadget_start(struct usb_gadget
> > *gadget, {
> >  	struct usbhsg_gpriv *gpriv = usbhsg_gadget_to_gpriv(gadget);
> >  	struct usbhs_priv *priv = usbhsg_gpriv_to_priv(gpriv);
> > +	struct device *dev = usbhs_priv_to_dev(priv);
> > +	int ret;
> >
> >  	if (!driver		||
> >  	    !driver->setup	||
> > @@ -891,6 +895,17 @@ static int usbhsg_gadget_start(struct usb_gadget
> > *gadget, /* first hook up the driver ... */
> >  	gpriv->driver = driver;
> >
> > +	/* connect to bus through transceiver */
> > +	if (!IS_ERR_OR_NULL(gpriv->transceiver)) {
> > +		ret = otg_set_peripheral(gpriv->transceiver->otg,
> > +					&gpriv->gadget);
> > +		if (ret) {
> > +			dev_err(dev, "%s: can't bind to transceiver\n",
> > +				gpriv->gadget.name);
> 
> Shouldn't gpriv->driver be set to NULL here ? Or possibly better, this code
> block moved before setting gpriv->driver ?
Makes sense.

> > +			return ret;
> > +		}
> > +	}
> > +
> >  	return usbhsg_try_start(priv, USBHSG_STATUS_REGISTERD);
> >  }
> >
> > @@ -900,6 +915,10 @@ static int usbhsg_gadget_stop(struct usb_gadget
> > *gadget) struct usbhs_priv *priv = usbhsg_gpriv_to_priv(gpriv);
> >
> >  	usbhsg_try_stop(priv, USBHSG_STATUS_REGISTERD);
> > +
> > +	if (!IS_ERR_OR_NULL(gpriv->transceiver))
> > +		(void) otg_set_peripheral(gpriv->transceiver->otg, NULL);
> 
> Is there really a need for (void) ?
Oops, none at all.

> > +
> >  	gpriv->driver = NULL;
> >
> >  	return 0;
> > @@ -947,12 +966,27 @@ static int usbhsg_set_selfpowered(struct usb_gadget
> > *gadget, int is_self) return 0;
> >  }
> >
> > +static int usbhsg_vbus_session(struct usb_gadget *gadget, int is_active)
> > +{
> > +	struct usbhsg_gpriv *gpriv = usbhsg_gadget_to_gpriv(gadget);
> > +	struct usbhs_priv *priv = usbhsg_gpriv_to_priv(gpriv);
> > +	struct platform_device *pdev = usbhs_priv_to_pdev(priv);
> > +
> > +	priv->vbus_is_indirect = 1;
> > +	priv->vbus_indirect_value = !!is_active;
> > +
> > +	renesas_usbhs_call_notify_hotplug(pdev);
> > +
> > +	return 0;
> > +}
> > +
> >  static const struct usb_gadget_ops usbhsg_gadget_ops = {
> >  	.get_frame		= usbhsg_get_frame,
> >  	.set_selfpowered	= usbhsg_set_selfpowered,
> >  	.udc_start		= usbhsg_gadget_start,
> >  	.udc_stop		= usbhsg_gadget_stop,
> >  	.pullup			= usbhsg_pullup,
> > +	.vbus_session		= usbhsg_vbus_session,
> >  };
> >
> >  static int usbhsg_start(struct usbhs_priv *priv)
> > @@ -994,6 +1028,10 @@ int usbhs_mod_gadget_probe(struct usbhs_priv
> *priv)
> >  		goto usbhs_mod_gadget_probe_err_gpriv;
> >  	}
> >
> > +	gpriv->transceiver = usb_get_phy(USB_PHY_TYPE_UNDEFINED);
> > +	dev_info(dev, "%s transceiver found\n",
> > +		 gpriv->transceiver ? "" : "No");
> > +
> >  	/*
> >  	 * CAUTION
> >  	 *
> 
> --
> Regards,
> 
> Laurent Pinchart

Thanks
Phil

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/