Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Message-ID: <1543472774.32173.114.camel@mhfsdcap03>
Subject: Re: [PATCH v4] usb/mtu3: power down device ip at setup
From:   Chunfeng Yun <chunfeng.yun@mediatek.com>
To:     "Hsin-Yi, Wang" <hsinyi@chromium.org>
CC:     <linux-arm-kernel@lists.infradead.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        <linux-usb@vger.kernel.org>, <linux-mediatek@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>
Date:   Thu, 29 Nov 2018 14:26:14 +0800
In-Reply-To: <20181129031627.45006-1-hsinyi@chromium.org>
References: <20181128095358.42498-1-hsinyi@chromium.org>
         <20181129031627.45006-1-hsinyi@chromium.org>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

hi Hsin-Yi,

On Thu, 2018-11-29 at 11:16 +0800, Hsin-Yi, Wang wrote:
> Originally, when dr_mode is USB_DR_MODE_HOST, it didn't power down device ip,
> so host ip sleep will fail at ssusb_host_disable.
> 
> Power down device ip at ssusb_host_setup.
> 
> Signed-off-by: Hsin-Yi, Wang <hsinyi@chromium.org>
> ---
> ChangeLog:
> V3->V4:
>   *update comment
> ---
>  drivers/usb/mtu3/mtu3_plat.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/usb/mtu3/mtu3_plat.c b/drivers/usb/mtu3/mtu3_plat.c
> index 46551f6d16fd..e086630e41a9 100644
> --- a/drivers/usb/mtu3/mtu3_plat.c
> +++ b/drivers/usb/mtu3/mtu3_plat.c
> @@ -200,6 +200,14 @@ static void ssusb_ip_sw_reset(struct ssusb_mtk *ssusb)
>  	mtu3_setbits(ssusb->ippc_base, U3D_SSUSB_IP_PW_CTRL0, SSUSB_IP_SW_RST);
>  	udelay(1);
>  	mtu3_clrbits(ssusb->ippc_base, U3D_SSUSB_IP_PW_CTRL0, SSUSB_IP_SW_RST);
> +
> +	/*
> +	 * device ip may be powered on in firmware/BROM stage before entering
> +	 * kernel stage;
> +	 * power down device ip, otherwise ip-sleep will fail when working as
> +	 * host only mode
> +	 */
> +	mtu3_setbits(ssusb->ippc_base, U3D_SSUSB_IP_PW_CTRL2, SSUSB_IP_DEV_PDN);
>  }
>  
>  /* ignore the error if the clock does not exist */

Acked-by: Chunfeng Yun <chunfeng.yun@mediatek.com>

Thanks a lot