From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Chen Subject: Re: [PATCH v6 08/15] usb: phy-mxs: Add implementation of nofity_suspend and notify_resume Date: Mon, 16 Dec 2013 09:12:05 +0800 Message-ID: <20131216011204.GA14183@shlinux1.ap.freescale.net> References: <1386897825-6130-1-git-send-email-peter.chen@freescale.com> <1386897825-6130-9-git-send-email-peter.chen@freescale.com> <20131213043236.GH867@saruman.home> <20131213200924.GI5292@saruman.home> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20131213200924.GI5292@saruman.home> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Felipe Balbi Cc: Marek =?utf-8?B?VmHFoXV0?= , devicetree@vger.kernel.org, m.grzeschik@pengutronix.de, frank.li@freescale.com, linux-doc@vger.kernel.org, Alexander Shishkin , Greg Kroah-Hartman , "linux-usb@vger.kernel.org" , rob.herring@calxeda.com, linux-arm-kernel@lists.infradead.org, kernel@pengutronix.de, grant.likely@linaro.org, Shawn Guo , Fabio Estevam , Peter Chen List-Id: devicetree@vger.kernel.org On Fri, Dec 13, 2013 at 02:09:24PM -0600, Felipe Balbi wrote: > On Fri, Dec 13, 2013 at 02:31:42PM +0800, Peter Chen wrote: > > On Fri, Dec 13, 2013 at 12:32 PM, Felipe Balbi wrote: > > > On Fri, Dec 13, 2013 at 09:23:38AM +0800, Peter Chen wrote: > > >> Implementation of notify_suspend and notify_resume will be different > > >> according to mxs_phy_data->flags. > > >> > > >> Signed-off-by: Peter Chen > > >> --- > > >> drivers/usb/phy/phy-mxs-usb.c | 55 ++++++++++++++++++++++++++++++++++++++--- > > >> 1 files changed, 51 insertions(+), 4 deletions(-) > > >> > > >> diff --git a/drivers/usb/phy/phy-mxs-usb.c b/drivers/usb/phy/phy-mxs-usb.c > > >> index 0ef930a..e3df53f 100644 > > >> --- a/drivers/usb/phy/phy-mxs-usb.c > > >> +++ b/drivers/usb/phy/phy-mxs-usb.c > > >> @@ -166,8 +166,8 @@ static int mxs_phy_suspend(struct usb_phy *x, int suspend) > > >> static int mxs_phy_on_connect(struct usb_phy *phy, > > >> enum usb_device_speed speed) > > >> { > > >> - dev_dbg(phy->dev, "%s speed device has connected\n", > > >> - (speed == USB_SPEED_HIGH) ? "high" : "non-high"); > > >> + dev_dbg(phy->dev, "%s device has connected\n", > > >> + (speed == USB_SPEED_HIGH) ? "HS" : "FS/LS"); > > > > > > unrelated. > > > > > >> @@ -179,8 +179,8 @@ static int mxs_phy_on_connect(struct usb_phy *phy, > > >> static int mxs_phy_on_disconnect(struct usb_phy *phy, > > >> enum usb_device_speed speed) > > >> { > > >> - dev_dbg(phy->dev, "%s speed device has disconnected\n", > > >> - (speed == USB_SPEED_HIGH) ? "high" : "non-high"); > > >> + dev_dbg(phy->dev, "%s device has disconnected\n", > > >> + (speed == USB_SPEED_HIGH) ? "HS" : "FS/LS"); > > > > > > unrelated. > > > > > > > Marek suggested using that string, I will added it at another patch. > > > > >> @@ -189,6 +189,48 @@ static int mxs_phy_on_disconnect(struct usb_phy *phy, > > >> return 0; > > >> } > > >> > > >> +static int mxs_phy_on_suspend(struct usb_phy *phy, > > >> + enum usb_device_speed speed) > > >> +{ > > >> + struct mxs_phy *mxs_phy = to_mxs_phy(phy); > > >> + > > >> + dev_dbg(phy->dev, "%s device has suspended\n", > > >> + (speed == USB_SPEED_HIGH) ? "HS" : "FS/LS"); > > >> + > > >> + /* delay 4ms to wait bus entering idle */ > > >> + usleep_range(4000, 5000); > > >> + > > >> + if (mxs_phy->data->flags & MXS_PHY_ABNORMAL_IN_SUSPEND) { > > >> + writel_relaxed(0xffffffff, phy->io_priv + HW_USBPHY_PWD); > > >> + writel_relaxed(0, phy->io_priv + HW_USBPHY_PWD); > > >> + } > > >> + > > >> + if (speed == USB_SPEED_HIGH) > > >> + writel_relaxed(BM_USBPHY_CTRL_ENHOSTDISCONDETECT, > > >> + phy->io_priv + HW_USBPHY_CTRL_CLR); > > > > > > why only on HS ? So if !HS and !ABNORMAL, this is no-op. > > > > > >> +static int mxs_phy_on_resume(struct usb_phy *phy, > > >> + enum usb_device_speed speed) > > >> +{ > > >> + dev_dbg(phy->dev, "%s device has resumed\n", > > >> + (speed == USB_SPEED_HIGH) ? "HS" : "FS/LS"); > > >> + > > >> + if (speed == USB_SPEED_HIGH) { > > >> + /* Make sure the device has switched to High-Speed mode */ > > >> + udelay(500); > > >> + writel_relaxed(BM_USBPHY_CTRL_ENHOSTDISCONDETECT, > > >> + phy->io_priv + HW_USBPHY_CTRL_SET); > > >> + } > > > > > > likewise, if !HS it's a no-op. > > > > > > > Correct, this operation is only needed for HS. > > > > >> @@ -235,6 +277,11 @@ static int mxs_phy_probe(struct platform_device *pdev) > > >> > > >> platform_set_drvdata(pdev, mxs_phy); > > >> > > >> + if (mxs_phy->data->flags & MXS_PHY_SENDING_SOF_TOO_FAST) { > > >> + mxs_phy->phy.notify_suspend = mxs_phy_on_suspend; > > >> + mxs_phy->phy.notify_resume = mxs_phy_on_resume; > > >> + } > > > > > > hmm, and seems like you only need notify_* on a buggy device. Sorry > > > Peter but you don't have enough arguments to make me agree with this > > > (and previous) patch. > > > > > > You gotta find a better way to handle this using normal phy > > > suspend/resume calls. > > > > > > > Like I explained at previous patch, it needs to be notified during > > ehci suspend/resume. > > I admit it is a SoC bug, but all SoCs have bugs, hmm. > > Software needs the solution to workaround it which breaks the standard USB spec. > > Then I think what you need is a real notification mechanism. usbcore > already notifies about buses and devices being added and removed, > perhaps you can convince Greg to accept suspend/resume notifications. > > With that, you can (conditionally) make this driver listen to usbcore > notifications. That'll be more work, but I guess it's best in the long > run as we won't need to keep on adding callbacks to the USB PHY > structure just because another buggy device showed up on the market. > Okay, I will add this notification to .set_suspend now, it can work most of cases except disconnect during the resume signal. Besides notification API add, how about other patches, eg add .set_wakeup API? If you think there are no big problems, I will send v7 version. -- Best Regards, Peter Chen