From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lan Tianyu Subject: Re: [PATCH 2/3] USB/ACPI: Add usb port's acpi power control in the xhci PORT_POWER feature request process. Date: Thu, 14 Jun 2012 15:22:42 +0800 Message-ID: <4FD99142.4010403@intel.com> References: <1339381474-17413-1-git-send-email-tianyu.lan@intel.com> <1339381474-17413-3-git-send-email-tianyu.lan@intel.com> <20120613193038.GA6312@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20120613193038.GA6312-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Greg KH Cc: lenb-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, sarah.a.sharp-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-acpi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, stern-nwvwT67g6+6dFdvTe/nMLpVzexx5G7lz@public.gmane.org List-Id: linux-acpi@vger.kernel.org On 2012=E5=B9=B406=E6=9C=8814=E6=97=A5 03:30, Greg KH wrote: > On Mon, Jun 11, 2012 at 10:24:33AM +0800, Lan Tianyu wrote: >> On our developping machine, bios can provide usb port's power contr= ol via >> acpi. This patch is to provide usb port's power control way through = setting >> or clearing PORT_POWER feature requests. Add two functions usb_acpi_= power_manageable() >> and usb_acpi_set_power_state(). The first one is used to find whethe= r the >> usb port has acpi power resource and the second is to set the power = state. >> They are invoked in the xhci_hub_control() where clearing or setting= PORT_POWER >> feature requests are processed. >> >> Signed-off-by: Lan Tianyu >> --- >> drivers/usb/core/usb-acpi.c | 28 ++++++++++++++++++++++++++++ >> drivers/usb/host/xhci-hub.c | 10 ++++++++++ >> include/linux/usb.h | 10 ++++++++++ >> 3 files changed, 48 insertions(+), 0 deletions(-) >> >> diff --git a/drivers/usb/core/usb-acpi.c b/drivers/usb/core/usb-acpi= =2Ec >> index 82c90d0..e95f26f 100644 >> --- a/drivers/usb/core/usb-acpi.c >> +++ b/drivers/usb/core/usb-acpi.c >> @@ -19,6 +19,34 @@ >> >> #include "usb.h" >> >> +bool usb_acpi_power_manageable(struct usb_device *hdev, int port1) >> +{ >> + acpi_handle port_handle; >> + >> + port_handle =3D usb_get_hub_port_acpi_handle(hdev, >> + port1); >> + return port_handle ? acpi_bus_power_manageable(port_handle) : fals= e; > > Ick, I _really_ hate the ? : usage in C, please use real if statement= s > so that everyone can read and understand them easier. You do that a = lot > here, please fix them all. > Ok. But in some places, for example dev_dbg(&hdev->dev, "The power of hub port %d was set to %s\n", port1, enable ? "enable" : "disable"); try to print two result. ?: is more convenient. If I use "if" statement= , that will be if (enable) result =3D "enable"; else result =3D "disable"; dev_dbg(&hdev->dev, "The power of hub port %d was set to %s\n", port1, result); This just looks a little complex. >> +} >> +EXPORT_SYMBOL_GPL(usb_acpi_power_manageable); >> + >> +int usb_acpi_set_power_state(struct usb_device *hdev, int port1, bo= ol enable) >> +{ >> + acpi_handle port_handle; >> + unsigned char state; >> + int error =3D -EINVAL; >> + >> + port_handle =3D (acpi_handle)usb_get_hub_port_acpi_handle(hdev, >> + port1); >> + state =3D enable ? ACPI_STATE_D0 : ACPI_STATE_D3_COLD; >> + error =3D acpi_bus_set_power(port_handle, state); > > You forgot to check port_handle here. > > Why not call usb_acpi_power_manageable() to ensure that you can do th= is? In my code, usb_acpi_power_manageable() is invoked before=20 usb_acpi_set_power_state(). Do you mean I should call usb_acpi_power_manageable() in the=20 usb_acpi_set_power_state()? > >> + if (!error) >> + dev_dbg(&hdev->dev, "The power of hub port %d was set to %s\n", >> + port1, enable ? "enable" : "disabe"); > > Why not report the error if debugging as well? Ok. > > >> + >> + return error; >> +} >> +EXPORT_SYMBOL_GPL(usb_acpi_set_power_state); >> + >> static int usb_acpi_check_port_connect_type(struct usb_device *hde= v, >> acpi_handle handle, int port1) >> { >> diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub= =2Ec >> index 2c55fcf..0ce48b3 100644 >> --- a/drivers/usb/host/xhci-hub.c >> +++ b/drivers/usb/host/xhci-hub.c >> @@ -728,6 +728,11 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 t= ypeReq, u16 wValue, >> >> temp =3D xhci_readl(xhci, port_array[wIndex]); >> xhci_dbg(xhci, "set port power, actual port %d status =3D 0x%x= \n", wIndex, temp); >> + >> + if (usb_acpi_power_manageable(hcd->self.root_hub, >> + wIndex + 1)) > > Why +1? If you have to do this everywhere, then do it only in the > function, so you can be 0 based properly. > > Also, minor coding style nit, please rewrite as: > if (usb_acpi_power_manageable(hcd->self.root_hub, > wIndex + 1)) > Or even better yet, use a temp variable for the value returned and th= en > check that, it's clearer and easier to read, right? > Yeah. Thanks for you suggestion. I will do it. >> + usb_acpi_set_power_state(hcd->self.root_hub, >> + wIndex + 1, true); > > Same question about +1 here. > >> break; >> case USB_PORT_FEAT_RESET: >> temp =3D (temp | PORT_RESET); >> @@ -830,6 +835,11 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 t= ypeReq, u16 wValue, >> case USB_PORT_FEAT_POWER: >> xhci_writel(xhci, temp& ~PORT_POWER, >> port_array[wIndex]); >> + >> + if (usb_acpi_power_manageable(hcd->self.root_hub, >> + wIndex + 1)) >> + usb_acpi_set_power_state(hcd->self.root_hub, >> + wIndex + 1, false); >> break; >> default: >> goto error; >> diff --git a/include/linux/usb.h b/include/linux/usb.h >> index feb0a04..92f8898 100644 >> --- a/include/linux/usb.h >> +++ b/include/linux/usb.h >> @@ -599,6 +599,16 @@ extern int usb_lock_device_for_reset(struct usb= _device *udev, >> extern int usb_reset_device(struct usb_device *dev); >> extern void usb_queue_reset_device(struct usb_interface *dev); >> >> +#ifdef CONFIG_ACPI >> +extern int usb_acpi_set_power_state(struct usb_device *hdev, int po= rt, >> + bool enable); >> +extern bool usb_acpi_power_manageable(struct usb_device *hdev, int = port); >> +#else >> +static inline int usb_acpi_set_power_state(struct usb_device *hdev,= int port, >> + bool enable) { return 0; } >> +static inline bool usb_acpi_power_manageable(struct usb_device *hde= v, int port) >> + { return 0; } > > is 0 a bool? :) > > Please get the types right. So careless. Thanks for reminder. > > greg k-h --=20 Best Regards Tianyu Lan linux kernel enabling team -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html