[PATCH 4.4 063/101] usb: dwc3: ep0: explicitly call dwc3_ep0_prepare_one_trb()

From: Greg Kroah-Hartman
Date: Tue Jan 10 2017 - 08:41:09 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>

commit 19ec31230eb3084431bc2e565fd085f79f564274 upstream.

Let's call dwc3_ep0_prepare_one_trb() explicitly
because there are occasions where we will need more
than one TRB to handle an EP0 transfer.

A follow-up patch will fix one bug related to
multiple-TRB Data Phases when it comes to
mapping/unmapping requests for DMA.

Reported-by: Janusz Dziedzic <januszx.dziedzic@xxxxxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>


---
drivers/usb/dwc3/ep0.c | 28 +++++++++++++++-------------
1 file changed, 15 insertions(+), 13 deletions(-)

--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -85,8 +85,7 @@ static void dwc3_ep0_prepare_one_trb(str
trace_dwc3_prepare_trb(dep, trb);
}

-static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
- u32 len, u32 type, bool chain)
+static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum)
{
struct dwc3_gadget_ep_cmd_params params;
struct dwc3_ep *dep;
@@ -98,8 +97,6 @@ static int dwc3_ep0_start_trans(struct d
return 0;
}

- dwc3_ep0_prepare_one_trb(dwc, epnum, buf_dma, len, type, chain);
-
memset(&params, 0, sizeof(params));
params.param0 = upper_32_bits(dwc->ep0_trb_addr);
params.param1 = lower_32_bits(dwc->ep0_trb_addr);
@@ -317,8 +314,9 @@ void dwc3_ep0_out_start(struct dwc3 *dwc
{
int ret;

- ret = dwc3_ep0_start_trans(dwc, 0, dwc->ctrl_req_addr, 8,
+ dwc3_ep0_prepare_one_trb(dwc, 0, dwc->ctrl_req_addr, 8,
DWC3_TRBCTL_CONTROL_SETUP, false);
+ ret = dwc3_ep0_start_trans(dwc, 0);
WARN_ON(ret < 0);
}

@@ -877,9 +875,9 @@ static void dwc3_ep0_complete_data(struc

dwc->ep0_next_event = DWC3_EP0_COMPLETE;

- ret = dwc3_ep0_start_trans(dwc, epnum,
- dwc->ctrl_req_addr, 0,
- DWC3_TRBCTL_CONTROL_DATA, false);
+ dwc3_ep0_prepare_one_trb(dwc, epnum, dwc->ctrl_req_addr,
+ 0, DWC3_TRBCTL_CONTROL_DATA, false);
+ ret = dwc3_ep0_start_trans(dwc, epnum);
WARN_ON(ret < 0);
}
}
@@ -961,9 +959,10 @@ static void __dwc3_ep0_do_control_data(s
req->direction = !!dep->number;

if (req->request.length == 0) {
- ret = dwc3_ep0_start_trans(dwc, dep->number,
+ dwc3_ep0_prepare_one_trb(dwc, dep->number,
dwc->ctrl_req_addr, 0,
DWC3_TRBCTL_CONTROL_DATA, false);
+ ret = dwc3_ep0_start_trans(dwc, dep->number);
} else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket)
&& (dep->number == 0)) {
u32 transfer_size = 0;
@@ -981,7 +980,7 @@ static void __dwc3_ep0_do_control_data(s
if (req->request.length > DWC3_EP0_BOUNCE_SIZE) {
transfer_size = ALIGN(req->request.length - maxpacket,
maxpacket);
- ret = dwc3_ep0_start_trans(dwc, dep->number,
+ dwc3_ep0_prepare_one_trb(dwc, dep->number,
req->request.dma,
transfer_size,
DWC3_TRBCTL_CONTROL_DATA,
@@ -993,9 +992,10 @@ static void __dwc3_ep0_do_control_data(s

dwc->ep0_bounced = true;

- ret = dwc3_ep0_start_trans(dwc, dep->number,
+ dwc3_ep0_prepare_one_trb(dwc, dep->number,
dwc->ep0_bounce_addr, transfer_size,
DWC3_TRBCTL_CONTROL_DATA, false);
+ ret = dwc3_ep0_start_trans(dwc, dep->number);
} else {
ret = usb_gadget_map_request(&dwc->gadget, &req->request,
dep->number);
@@ -1004,9 +1004,10 @@ static void __dwc3_ep0_do_control_data(s
return;
}

- ret = dwc3_ep0_start_trans(dwc, dep->number, req->request.dma,
+ dwc3_ep0_prepare_one_trb(dwc, dep->number, req->request.dma,
req->request.length, DWC3_TRBCTL_CONTROL_DATA,
false);
+ ret = dwc3_ep0_start_trans(dwc, dep->number);
}

WARN_ON(ret < 0);
@@ -1020,8 +1021,9 @@ static int dwc3_ep0_start_control_status
type = dwc->three_stage_setup ? DWC3_TRBCTL_CONTROL_STATUS3
: DWC3_TRBCTL_CONTROL_STATUS2;

- return dwc3_ep0_start_trans(dwc, dep->number,
+ dwc3_ep0_prepare_one_trb(dwc, dep->number,
dwc->ctrl_req_addr, 0, type, false);
+ return dwc3_ep0_start_trans(dwc, dep->number);
}

static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep)