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

[Kishon Vijay Abraham I]

Hi,

On Monday 16 February 2015 06:34 PM, Lukasz Majewski wrote:
> 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 ...).

ah.. alright.

Thanks
Kishon