[PATCH 3/4] usb: musb: Fix handling interrupts for EP0 and SET ADDRESS commmand

[Pali Rohár]

On Saturday 23 January 2021 16:16:11 Lukasz Majewski wrote:
> Hi Pali,
> 
> > Interrupt for EP0 is indicated in intrtx register via first bit. It
> > is set for both RX and TX. First bit in intrrx register is reserved
> > and not set.
> > 
> > So remove calling musb_peri_ep0() function at every iteration of
> > udc_irq() and musb_peri_rx() and call it only from musb_peri_tx()
> > when correct interrupt bit in initrtx it set.
> > 
> > Address from SET ADDRESS command must be set to faddr register only
> > after acknowledging SERV_RXPKTRDY followed by received EP0 interrupt.
> > So prior calling musb_peri_ep0_set_address() check for EP0 interrupt
> > instead of (incorrect) MUSB_INTR_SOF interrupt.
> > 
> > This patch fixes issue that host (computer) cannot register U-Boot USB
> > device and failing with errors:
> > 
> >     usb 1-1: new full-speed USB device number 86 using xhci_hcd
> >     usb 1-1: Device not responding to setup address.
> >     usb 1-1: Device not responding to setup address.
> >     usb 1-1: device not accepting address 86, error -71
> > 
> > U-Boot was writing address to faddr register too early and did not
> > wait for correct interrupt after which should update address.
> > 
> > Signed-off-by: Pali Rohár <pali at kernel.org>
> > ---
> >  drivers/usb/musb/musb_udc.c | 12 ++++--------
> >  1 file changed, 4 insertions(+), 8 deletions(-)
> > 
> > diff --git a/drivers/usb/musb/musb_udc.c b/drivers/usb/musb/musb_udc.c
> > index 7c74422623..50d8bc319c 100644
> > --- a/drivers/usb/musb/musb_udc.c
> > +++ b/drivers/usb/musb/musb_udc.c
> > @@ -707,9 +707,7 @@ static void musb_peri_rx(u16 intr)
> >  {
> >  	unsigned int ep;
> >  
> > -	/* Check for EP0 */
> > -	if (0x01 & intr)
> > -		musb_peri_ep0();
> > +	/* First bit is reserved and does not indicate interrupt for
> > EP0 */ 
> >  	for (ep = 1; ep < 16; ep++) {
> >  		if ((1 << ep) & intr)
> > @@ -721,9 +719,9 @@ static void musb_peri_tx(u16 intr)
> >  {
> >  	unsigned int ep;
> >  
> > -	/* Check for EP0 */
> > +	/* Check for EP0: first bit indicates interrupt for both RX
> > and TX */ if (0x01 & intr)
> > -		musb_peri_ep0_tx();
> > +		musb_peri_ep0();
> >  
> >  	for (ep = 1; ep < 16; ep++) {
> >  		if ((1 << ep) & intr)
> > @@ -750,8 +748,6 @@ void udc_irq(void)
> >  			musb_peri_resume();
> >  		}
> >  
> > -		musb_peri_ep0();
> > -
> >  		if (MUSB_INTR_RESET & intrusb) {
> >  			usbd_device_event_irq(udc_device,
> > DEVICE_RESET, 0); musb_peri_reset();
> > @@ -790,7 +786,7 @@ void udc_irq(void)
> >  			if (intrtx)
> >  				musb_peri_tx(intrtx);
> >  		} else {
> > -			if (MUSB_INTR_SOF & intrusb) {
> > +			if (readw(&musbr->intrtx) & 0x1) {
> >  				u8 faddr;
> >  				faddr = readb(&musbr->faddr);
> >  				/*
> 
> Applying this patch causes error. Could you rebase your work on newest
> master (after onging PR is accepted).

Hello! This patch series is rebased on top of the another patch series
"Nokia RX-51: Fix USB TTY console and enable it" as it depends on it.
So I cannot rebase it on top of master as it would not work.

Nokia RX-51: Fix USB TTY console and enable it:
<20201129164618.5829-1-pali at kernel.org>
https://lists.denx.de/pipermail/u-boot/2020-November/433728.html

> Thanks in advance and sorry for delay.
> 
> 
> Best regards,
> 
> Lukasz Majewski
> 
> --
> 
> DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
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