On Mon, Jun 05, 2017 at 10:16:34AM -0400, Alan Stern wrote: > On Mon, 5 Jun 2017, Peter Chen wrote: > > > On Thu, May 18, 2017 at 08:49:00AM +0800, Peter Chen wrote: > > > Some hard-wired USB devices need to do power sequence to let the > > > device work normally, the typical power sequence like: enable USB > > > PHY clock, toggle reset pin, etc. But current Linux USB driver > > > lacks of such code to do it, it may cause some hard-wired USB devices > > > works abnormal or can't be recognized by controller at all. > > > > > > In this patch, it calls power sequence library APIs to finish > > > the power sequence events. It will do power on sequence at hub's > > > probe for all devices under this hub (includes root hub). > > > At hub_disconnect, it will do power off sequence which is at powered > > > on list. > > > > > > > Greg, Alan, would you please help on reviewing it? It seems Rafael > > is waiting for USB MAINTAINERS's comments or ack. It resolves some > > USB HUB issues for several persons. > > > > Peter > > > > > Signed-off-by: Peter Chen <peter.chen@xxxxxxx> > > > Tested-by Joshua Clayton <stillcompiling@xxxxxxxxx> > > > Tested-by: Maciej S. Szmigiero <mail@xxxxxxxxxxxxxxxxxxxxx> > > > Reviewed-by: Vaibhav Hiremath <hvaibhav.linux@xxxxxxxxx> > > Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> > > > > --- > > > drivers/usb/Kconfig | 1 + > > > drivers/usb/core/hub.c | 49 +++++++++++++++++++++++++++++++++++++++++++++---- > > > drivers/usb/core/hub.h | 1 + > > > 3 files changed, 47 insertions(+), 4 deletions(-) > > > > > > diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig > > > index 939a63b..b6f626e 100644 > > > --- a/drivers/usb/Kconfig > > > +++ b/drivers/usb/Kconfig > > > @@ -39,6 +39,7 @@ config USB > > > tristate "Support for Host-side USB" > > > depends on USB_ARCH_HAS_HCD > > > select USB_COMMON > > > + select POWER_SEQUENCE > > > select NLS # for UTF-8 strings > > > ---help--- > > > Universal Serial Bus (USB) is a specification for a serial bus > > > diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c > > > index 9dca59e..7a67296 100644 > > > --- a/drivers/usb/core/hub.c > > > +++ b/drivers/usb/core/hub.c > > > @@ -28,6 +28,7 @@ > > > #include <linux/mutex.h> > > > #include <linux/random.h> > > > #include <linux/pm_qos.h> > > > +#include <linux/power/pwrseq.h> > > > > > > #include <linux/uaccess.h> > > > #include <asm/byteorder.h> > > > @@ -1619,6 +1620,7 @@ static void hub_disconnect(struct usb_interface *intf) > > > hub->error = 0; > > > hub_quiesce(hub, HUB_DISCONNECT); > > > > > > + of_pwrseq_off_list(&hub->pwrseq_on_list); > > Things like this look a little peculiar -- you are passing an "on_list" > to a function named "...off_list". > > How about naming the new field hub->pwrseq_list instead? > Thanks, Alan. I will change it at next revision. -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
