[U-Boot] [u-boot 32/40] usb: dwc3: Add chained TRB support for ep0

[Lukasz Majewski]

Hi Kishon,

> Hi Lukasz,
> 
> On Monday 16 February 2015 05:12 PM, Lukasz Majewski wrote:
> > Hi Kishon,
> >
> >> dwc3 can do only max packet aligned transfers. So in case request
> >> length is not max packet aligned and is bigger than
> >> DWC3_EP0_BOUNCE_SIZE two chained TRBs is required to handle the
> >> transfer.
> >>
> >> Signed-off-by: Kishon Vijay Abraham I <kishon at ti.com>
> >> ---
> >>   drivers/usb/dwc3/ep0.c    |   72
> >> +++++++++++++++++++++++++++++++++------------
> >> drivers/usb/dwc3/gadget.c |    2 +- 2 files changed, 55
> >> insertions(+), 19 deletions(-)
> >>
> >> diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
> >> index fce2558..c2fe0ec 100644
> >> --- a/drivers/usb/dwc3/ep0.c
> >> +++ b/drivers/usb/dwc3/ep0.c
> >> @@ -48,7 +48,7 @@ static const char *dwc3_ep0_state_string(enum
> >> dwc3_ep0_state state) }
> >>
> >>   static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum,
> >> dma_addr_t buf_dma,
> >> -		u32 len, u32 type)
> >> +				u32 len, u32 type, unsigned chain)
> >>   {
> >>   	struct dwc3_gadget_ep_cmd_params params;
> >>   	struct dwc3_trb			*trb;
> >> @@ -62,7 +62,10 @@ static int dwc3_ep0_start_trans(struct dwc3
> >> *dwc, u8 epnum, dma_addr_t buf_dma, return 0;
> >>   	}
> >>
> >> -	trb = dwc->ep0_trb;
> >> +	trb = &dwc->ep0_trb[dep->free_slot];
> >> +
> >> +	if (chain)
> >> +		dep->free_slot++;
> >>
> >>   	trb->bpl = lower_32_bits(buf_dma);
> >>   	trb->bph = upper_32_bits(buf_dma);
> >> @@ -70,13 +73,20 @@ static int dwc3_ep0_start_trans(struct dwc3
> >> *dwc, u8 epnum, dma_addr_t buf_dma, trb->ctrl = type;
> >>
> >>   	trb->ctrl |= (DWC3_TRB_CTRL_HWO
> >> -			| DWC3_TRB_CTRL_LST
> >> -			| DWC3_TRB_CTRL_IOC
> >>   			| DWC3_TRB_CTRL_ISP_IMI);
> >>
> >> +	if (chain)
> >> +		trb->ctrl |= DWC3_TRB_CTRL_CHN;
> >> +	else
> >> +		trb->ctrl |= (DWC3_TRB_CTRL_IOC
> >> +				| DWC3_TRB_CTRL_LST);
> >> +
> >>   	dwc3_flush_cache((int)buf_dma, len);
> >>   	dwc3_flush_cache((int)trb, sizeof(*trb));
> >>
> >> +	if (chain)
> >> +		return 0;
> >> +
> >>   	memset(&params, 0, sizeof(params));
> >>   	params.param0 = upper_32_bits(dwc->ep0_trb_addr);
> >>   	params.param1 = lower_32_bits(dwc->ep0_trb_addr);
> >> @@ -289,7 +299,7 @@ void dwc3_ep0_out_start(struct dwc3 *dwc)
> >>   	int				ret;
> >>
> >>   	ret = dwc3_ep0_start_trans(dwc, 0, dwc->ctrl_req_addr, 8,
> >> -			DWC3_TRBCTL_CONTROL_SETUP);
> >> +				   DWC3_TRBCTL_CONTROL_SETUP, 0);
> >>   	WARN_ON(ret < 0);
> >>   }
> >>
> >> @@ -799,6 +809,23 @@ static void dwc3_ep0_complete_data(struct dwc3
> >> *dwc,
> >>   	maxp = ep0->endpoint.maxpacket;
> >>
> >> +	/* Handle the first TRB before handling the bounce buffer
> >> if the request
> >
> > 	Minor comment - please fix above comment.
> 
> Sorry. Didn't get what should I fix here?

	The comment should be as follow:

	/*
	 * Handle the first .....
	 *
	 *
	 */

The first line is wrong (/* Handle ...).

> 
> Btw thanks for reviewing all the patches.
> 
> Cheers
> Kishon


-- 
Best regards,

Lukasz Majewski

Samsung R&D Institute Poland (SRPOL) | Linux Platform Group