> -----Original Message----- > From: Sergei Shtylyov [mailto:sshtylyov@xxxxxxxxxx] > Sent: 2011年11月28日 18:56 > To: Neil Zhang > Cc: balbi@xxxxxx; stern@xxxxxxxxxxxxxxxxxxx; gregkh@xxxxxxx; linux- > usb@xxxxxxxxxxxxxxx; Chao Xie > Subject: Re: [PATCH 4/7 v1] usb: gadget: mv_udc: disable ISR when > stopped > > Hello. > > On 28-11-2011 6:09, Neil Zhang wrote: > > >>> When device is stopped, there is no need to handle ISR. > >>> Especially when otg switch to HOST mode. > > >>> Change-Id: I17ccb8eee5162c52ba1761d2d471f77c14d89da9 > > >> This line has no place in the upstream patch -- remove it > please. > > > > Thanks for your remind. > > >>> Signed-off-by: Neil Zhang<zhangwm@xxxxxxxxxxx> > >>> --- > >>> drivers/usb/gadget/mv_udc.h | 3 ++- > >>> drivers/usb/gadget/mv_udc_core.c | 8 ++++++++ > >>> 2 files changed, 10 insertions(+), 1 deletions(-) > > >>> diff --git a/drivers/usb/gadget/mv_udc_core.c > >> b/drivers/usb/gadget/mv_udc_core.c > >>> index c7c0bfa..e852f9d 100644 > >>> --- a/drivers/usb/gadget/mv_udc_core.c > >>> +++ b/drivers/usb/gadget/mv_udc_core.c > >>> @@ -1056,6 +1056,8 @@ static void udc_stop(struct mv_udc *udc) > >>> USBINTR_PORT_CHANGE_DETECT_EN | USBINTR_RESET_EN); > >>> writel(tmp,&udc->op_regs->usbintr); > >>> > >>> + udc->stopped = 1; > >>> + > >>> /* Reset the Run the bit in the command register to stop > VUSB */ > >>> tmp = readl(&udc->op_regs->usbcmd); > >>> tmp&= ~USBCMD_RUN_STOP; > >>> @@ -1072,6 +1074,8 @@ static void udc_start(struct mv_udc *udc) > >>> /* Enable interrupts */ > >>> writel(usbintr,&udc->op_regs->usbintr); > >>> > >>> + udc->stopped = 0; > >>> + > >>> /* Set the Run bit in the command register */ > >>> writel(USBCMD_RUN_STOP,&udc->op_regs->usbcmd); > >>> } > >>> @@ -2040,6 +2044,10 @@ static irqreturn_t mv_udc_irq(int irq, void > >> *dev) > >>> struct mv_udc *udc = (struct mv_udc *)dev; > >>> u32 status, intr; > >>> > >>> + /* Disable ISR when stopped bit is set */ > >>> + if (udc->stopped) > >>> + return IRQ_NONE; > > >> Can't this lead to the interrupt storm and masking the > interrupt as > >> a result? > >> You'd better mask off interrupts via your hardware's interrupt mask > >> register. > > > Yes, we will mask the interrupt when stop the gadget. But this irq > line > > is shared between gadget and host driver, if the host is not active, > there > > will be no interrupt here, so I think it Should be OK here to return > IRQ_NONE. > > And if the host is active? Aren't you checking the gadget interrupt > status > register in order to know if it's gadget's interrupt? You should if not, > and > so your new code seems to have no sense at all. > Do you mean it is better to check USBMODE register instead of using flag stopped? > >> WBR, Sergei > > > Best Regards, > > Neil Zhang > > WBR, Sergei Best Regards, Neil Zhang ?韬{.n?????%??檩??w?{.n???{炳???骅w* jg????????G??⒏ ⒎?:+v???????? ????＂??????
