From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161169AbcFQNVX (ORCPT ); Fri, 17 Jun 2016 09:21:23 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:50599 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753023AbcFQNVV (ORCPT ); Fri, 17 Jun 2016 09:21:21 -0400 Subject: Re: [PATCH v6 2/2] phy: rockchip-inno-usb2: add a new driver for Rockchip usb2phy To: Frank Wang , heiko@sntech.de References: <1466129353-48063-1-git-send-email-frank.wang@rock-chips.com> <1466129353-48063-3-git-send-email-frank.wang@rock-chips.com> <576383C6.3050005@roeck-us.net> <98bc69af-c597-d1ee-e83d-c7b5918e9ef4@rock-chips.com> Cc: dianders@chromium.org, groeck@chromium.org, jwerner@chromium.org, kishon@ti.com, robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-usb@vger.kernel.org, linux-rockchip@lists.infradead.org, xzy.xu@rock-chips.com, kever.yang@rock-chips.com, huangtao@rock-chips.com, william.wu@rock-chips.com From: Guenter Roeck Message-ID: <5763F92D.80102@roeck-us.net> Date: Fri, 17 Jun 2016 06:20:45 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.8.0 MIME-Version: 1.0 In-Reply-To: <98bc69af-c597-d1ee-e83d-c7b5918e9ef4@rock-chips.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Authenticated_sender: linux@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: linux@roeck-us.net X-Authenticated-Sender: bh-25.webhostbox.net: linux@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Frank, On 06/16/2016 11:43 PM, Frank Wang wrote: > Hi Guenter, > > On 2016/6/17 12:59, Guenter Roeck wrote: >> On 06/16/2016 07:09 PM, Frank Wang wrote: >>> The newer SoCs (rk3366, rk3399) take a different usb-phy IP block >>> than rk3288 and before, and most of phy-related registers are also >>> different from the past, so a new phy driver is required necessarily. >>> >>> Signed-off-by: Frank Wang >>> Suggested-by: Guenter Roeck >>> Suggested-by: Doug Anderson >>> Reviewed-by: Heiko Stuebner >>> Tested-by: Heiko Stuebner >>> --- >> >> [ ... ] >> >>> + >>> +static int rockchip_usb2phy_resume(struct phy *phy) >>> +{ >>> + struct rockchip_usb2phy_port *rport = phy_get_drvdata(phy); >>> + struct rockchip_usb2phy *rphy = dev_get_drvdata(phy->dev.parent); >>> + int ret; >>> + >>> + dev_dbg(&rport->phy->dev, "port resume\n"); >>> + >>> + ret = clk_prepare_enable(rphy->clk480m); >>> + if (ret) >>> + return ret; >>> + >> If suspend can be called multiple times, resume can be called >> multiple times as well. Doesn't this cause a clock imbalance >> if you call clk_prepare_enable() multiple times on resume, >> but clk_disable_unprepare() only once on suspend ? >> > > Well, what you said is reasonable, How does something like below? > > @@ -307,6 +307,9 @@ static int rockchip_usb2phy_resume(struct phy *phy) > > dev_dbg(&rport->phy->dev, "port resume\n"); > > + if (!rport->suspended) > + return 0; > + > ret = clk_prepare_enable(rphy->clk480m); > if (ret) > return ret; > @@ -327,12 +330,16 @@ static int rockchip_usb2phy_suspend(struct phy *phy) > > dev_dbg(&rport->phy->dev, "port suspend\n"); > > + if (rport->suspended) > + return 0; > + > ret = property_enable(rphy, &rport->port_cfg->phy_sus, true); > if (ret) > return ret; > > rport->suspended = true; > clk_disable_unprepare(rphy->clk480m); > + > return 0; > } > > @@ -485,6 +492,7 @@ static int rockchip_usb2phy_host_port_init(struct rockchip_usb2phy *rphy, > > rport->port_id = USB2PHY_PORT_HOST; > rport->port_cfg = &rphy->phy_cfg->port_cfgs[USB2PHY_PORT_HOST]; > + rport->suspended = true; > Why does it start in suspended mode ? That seems odd. Guenter > mutex_init(&rport->mutex); > INIT_DELAYED_WORK(&rport->sm_work, rockchip_usb2phy_sm_work); >