Hi Alan, > -----Original Message----- > From: Alan Stern [mailto:stern@xxxxxxxxxxxxxxxxxxx] > Sent: 2016年8月4日 23:02 > To: Wenyou Yang <wenyou.yang@xxxxxxxxx> > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>; Nicolas Ferre > <nicolas.ferre@xxxxxxxxx>; Alexandre Belloni <alexandre.belloni@free- > electrons.com>; linux-kernel@xxxxxxxxxxxxxxx; linux-arm- > kernel@xxxxxxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx > Subject: Re: [PATCH v5] usb: ohci-at91: Forcibly suspend ports while USB > suspend > > On Thu, 4 Aug 2016, Wenyou Yang wrote: > > > The usb controller does not managed correctly the suspend mode for the > > ehci. In echi mode, there is no way to have utmi_suspend_o_n[1] > > suspend without any device connected to it. This is why this specific > > control is added to fix this issue. The suspend mode works in ohci > > mode. > > Why are you talking about EHCI mode? This patch is only for the > ohci-at91 driver. Actually I described the issue according to the documents from our IP, and this specific control is recommended to do in ohci mode. > > > This specific control is by setting the SUSPEND_A/B/C fields of > > SFR_OHCIICR(OHCI Interrupt Configuration Register) in the SFR while > > OHCI USB suspend. > > > > This setting operation must be done before the USB clock disabled, > > clear them after the USB clock enabled. > > > > Signed-off-by: Wenyou Yang <wenyou.yang@xxxxxxxxx> > > Reviewed-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx> > > Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx> > > I don't know if this is any better than before! See the comments below. Yes, I think so. What else advice? > > > --- > > > > Changes in v5: > > - Use the USB_PORT_FEAT_SUSPEND subcase of the SetPortFeature case > > to take care it. > > - Update the commit log. > > > > Changes in v4: > > - To check whether the SFR node with "atmel,sama5d2-sfr" compatible > > is present or not to decide if this feature is applied or not > > when USB OHCI suspend/resume, instead of new compatible. > > - Drop the compatible "atmel,sama5d2-ohci". > > - Drop [PATCH 2/2] ARM: at91/dt: sama5d2: Use new compatible for > > ohci node. > > - Drop include/soc/at91/at91_sfr.h, move the macro definitions to > > atmel-sfr.h which already exists. > > - Change the defines to align the exists. > > > > Changes in v3: > > - Change the compatible description for more precise. > > > > Changes in v2: > > - Add compatible to support forcibly suspend the ports. > > - Add soc/at91/at91_sfr.h to accommodate the defines. > > - Add error checking for .sfr_regmap. > > - Remove unnecessary regmap_read() statement. > > > > @@ -282,6 +301,28 @@ static int ohci_at91_hub_status_data(struct usb_hcd > *hcd, char *buf) > > return length; > > } > > > > +static int ohci_at91_port_ctrl(struct regmap *regmap, u16 port, u8 > > +set) { > > + u32 regval; > > + int ret; > > + > > + if (!regmap) > > + return 0; > > + > > + ret = regmap_read(regmap, AT91_SFR_OHCIICR, ®val); > > + if (ret) > > + return ret; > > + > > + if (set) > > + regval |= AT91_OHCIICR_SUSPEND(port); > > + else > > + regval &= ~AT91_OHCIICR_SUSPEND(port); > > In the earlier versions of this patch, you did not use the port number. > Why has this changed? This function is called by ohci_at91_hub_control(), which is invoked on basis of port number. So, I think it is more reasonable of adding the port argument. > > How many ports does this controller have? This controller has three ports. > > > + > > + regmap_write(regmap, AT91_SFR_OHCIICR, regval); > > + > > + return 0; > > +} > > + > > /* > > * Look at the control requests to the root hub and see if we need to override. > > */ > > @@ -289,6 +330,7 @@ static int ohci_at91_hub_control(struct usb_hcd *hcd, > u16 typeReq, u16 wValue, > > u16 wIndex, char *buf, u16 wLength) { > > struct at91_usbh_data *pdata = > > dev_get_platdata(hcd->self.controller); > > + struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd); > > struct usb_hub_descriptor *desc; > > int ret = -EINVAL; > > u32 *data = (u32 *)buf; > > @@ -301,7 +343,8 @@ static int ohci_at91_hub_control(struct usb_hcd > > *hcd, u16 typeReq, u16 wValue, > > > > switch (typeReq) { > > case SetPortFeature: > > - if (wValue == USB_PORT_FEAT_POWER) { > > + switch (wValue) { > > + case USB_PORT_FEAT_POWER: > > dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n"); > > if (valid_port(wIndex)) { > > ohci_at91_usb_set_power(pdata, wIndex, 1); @@ > -309,6 +352,11 @@ > > static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, > > } > > > > goto out; > > + > > + case USB_PORT_FEAT_SUSPEND: > > + dev_dbg(hcd->self.controller, "SetPortFeat: SUSPEND\n"); > > + ohci_at91_port_ctrl(ohci_at91->sfr_regmap, wIndex, 1); > > + break; > > } > > break; > > > > @@ -342,6 +390,12 @@ static int ohci_at91_hub_control(struct usb_hcd *hcd, > u16 typeReq, u16 wValue, > > ohci_at91_usb_set_power(pdata, wIndex, 0); > > return 0; > > } > > + break; > > + > > + case USB_PORT_FEAT_SUSPEND: > > + dev_dbg(hcd->self.controller, "ClearPortFeature: > SUSPEND\n"); > > + ohci_at91_port_ctrl(ohci_at91->sfr_regmap, wIndex, 0); > > + break; > > } > > break; > > } > > Note that after all this, the code goes ahead to call ohci_bub_control(). Yes, The ohci_bub_control() will change the port_status[port] register after this operation. > > > @@ -587,7 +641,8 @@ ohci_hcd_at91_drv_suspend(struct device *dev) > > struct usb_hcd *hcd = dev_get_drvdata(dev); > > struct ohci_hcd *ohci = hcd_to_ohci(hcd); > > struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd); > > - int ret; > > + u16 i; > > + int ret; > > > > /* > > * Disable wakeup if we are going to sleep with slow clock mode @@ > > -599,6 +654,11 @@ ohci_hcd_at91_drv_suspend(struct device *dev) > > if (ohci_at91->wakeup) > > enable_irq_wake(hcd->irq); > > > > + for (i = 0; i < ohci->num_ports; i++) { > > + ohci_at91_hub_control(hcd, SetPortFeature, > > + USB_PORT_FEAT_SUSPEND, (i + 1), NULL, > 0); > > + } > > + > > ret = ohci_suspend(hcd, ohci_at91->wakeup); > > Do you really want to call ohci_hub_control() for ports that don't have a device > attached? Yes. I need to do this operation for ports that don't have a device attached. > > > if (ret) { > > if (ohci_at91->wakeup) > > @@ -630,7 +690,9 @@ static int __maybe_unused > > ohci_hcd_at91_drv_resume(struct device *dev) { > > struct usb_hcd *hcd = dev_get_drvdata(dev); > > + struct ohci_hcd *ohci = hcd_to_ohci(hcd); > > struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd); > > + u16 i; > > > > if (ohci_at91->wakeup) > > disable_irq_wake(hcd->irq); > > @@ -638,6 +700,12 @@ ohci_hcd_at91_drv_resume(struct device *dev) > > at91_start_clock(ohci_at91); > > > > ohci_resume(hcd, false); > > + > > + for (i = 0; i < ohci->num_ports; i++) { > > + ohci_at91_hub_control(hcd, ClearPortFeature, > > + USB_PORT_FEAT_SUSPEND, i + 1, NULL, > 0); > > + } > > Have you thought about how this will interact with runtime PM? > > If you intend to do this only for system suspend and not for runtime suspend, why > not set all the suspend bits for all the ports in the OHCIICR register at once, in a > single write, like you were doing before? Yes, this is only for system suspend. As I mentioned above, here calls ohci_at91_hub_control(), which is based on port number. > > Alan Stern Best Regards, Wenyou Yang ?韬{.n?????%??檩??w?{.n???{炳???骅w* jg????????G??⒏ ⒎?:+v???????? ????＂??????
