linux-kernel - Re: [PATCH v7 2/5] usb: chipidea: msm: Configure phy for appropriate mode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20170122021059.GA6522@b29397-desktop>
Date:   Sun, 22 Jan 2017 10:10:59 +0800
From:   Peter Chen <hzpeterchen@...il.com>
To:     Stephen Boyd <stephen.boyd@...aro.org>
Cc:     Peter Chen <peter.chen@....com>,
        Kishon Vijay Abraham I <kishon@...com>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linux-arm-msm@...r.kernel.org, Andy Gross <andy.gross@...aro.org>,
        Bjorn Andersson <bjorn.andersson@...aro.org>,
        Neil Armstrong <narmstrong@...libre.com>,
        Arnd Bergmann <arnd@...db.de>, Felipe Balbi <balbi@...nel.org>,
        linux-usb@...r.kernel.org,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: Re: [PATCH v7 2/5] usb: chipidea: msm: Configure phy for appropriate
 mode

On Fri, Jan 20, 2017 at 10:50:54AM -0800, Stephen Boyd wrote:
> When the qcom chipidea controller is used with an extcon, we need
> to signal device mode or host mode to the phy so it can configure
> itself for the correct mode. This should be done after the phy is
> powered up, so that the register writes work correctly. Add in
> the appropriate phy_set_mode() call here.
> 
> To signal the correct state to the qcom glue driver we need to
> change the ci->role before we do the role switch. Make sure to
> undo the change if the role switch fails, but otherwise update
> the state before calling the role start function so that the glue
> driver knows what state to configure for.
> 
> Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
> Signed-off-by: Stephen Boyd <stephen.boyd@...aro.org>
> ---
> 
> Made this msm specific because of how msm handles phy powerup.
> 
>  drivers/usb/chipidea/ci.h          | 7 +++++--
>  drivers/usb/chipidea/ci_hdrc_msm.c | 4 ++++
>  2 files changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/chipidea/ci.h b/drivers/usb/chipidea/ci.h
> index 59e22389c10b..18348b0529af 100644
> --- a/drivers/usb/chipidea/ci.h
> +++ b/drivers/usb/chipidea/ci.h
> @@ -268,6 +268,7 @@ static inline struct ci_role_driver *ci_role(struct ci_hdrc *ci)
>  static inline int ci_role_start(struct ci_hdrc *ci, enum ci_role role)
>  {
>  	int ret;
> +	enum ci_role prev_role;
>  
>  	if (role >= CI_ROLE_END)
>  		return -EINVAL;
> @@ -275,9 +276,11 @@ static inline int ci_role_start(struct ci_hdrc *ci, enum ci_role role)
>  	if (!ci->roles[role])
>  		return -ENXIO;
>  
> +	prev_role = ci->role;
> +	ci->role = role;
>  	ret = ci->roles[role]->start(ci);
> -	if (!ret)
> -		ci->role = role;
> +	if (ret)
> +		ci->role = prev_role;
>  	return ret;

Sorry, this changes ci->role's life cycle. You may try to get coming
role at your glue layer code (eg, through usbmode), or add your
changes at ci_role_start directly if the sequence can make your requirement.

Peter
>  }
>  
> diff --git a/drivers/usb/chipidea/ci_hdrc_msm.c b/drivers/usb/chipidea/ci_hdrc_msm.c
> index f1ede7909f54..9c58d13970ca 100644
> --- a/drivers/usb/chipidea/ci_hdrc_msm.c
> +++ b/drivers/usb/chipidea/ci_hdrc_msm.c
> @@ -125,6 +125,10 @@ static int ci_hdrc_msm_notify_event(struct ci_hdrc *ci, unsigned event)
>  			hw_write(ci, OP_USBCMD, HSPHY_SESS_VLD_CTRL,
>  				 HSPHY_SESS_VLD_CTRL);
>  
> +			if (ci->role == CI_ROLE_GADGET)
> +				phy_set_mode(ci->phy, PHY_MODE_USB_DEVICE);
> +			else if (ci->role == CI_ROLE_HOST)
> +				phy_set_mode(ci->phy, PHY_MODE_USB_HOST);
>  		}
>  		break;
>  	case CI_HDRC_CONTROLLER_STOPPED_EVENT:
> -- 
> 2.10.0.297.gf6727b0
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-usb" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

-- 

Best Regards,
Peter Chen