@@ -1034,8 +1034,7 @@ static void __dwc3_prepare_one_trb(struct dwc3_ep *dep, struct dwc3_trb *trb,
trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
}
- if ((!no_interrupt && !chain) || must_interrupt ||
- (dwc3_calc_trbs_left(dep) == 1))
+ if ((!no_interrupt && !chain) || must_interrupt)
trb->ctrl |= DWC3_TRB_CTRL_IOC;
if (chain)
@@ -1169,6 +1168,7 @@ static int dwc3_prepare_trbs_sg(struct dwc3_ep *dep,
length -= sg_dma_len(s);
for_each_sg(sg, s, remaining, i) {
+ unsigned int num_trbs_left = dwc3_calc_trbs_left(dep);
unsigned int trb_length;
bool must_interrupt = false;
bool last_sg = false;
@@ -1187,7 +1187,7 @@ static int dwc3_prepare_trbs_sg(struct dwc3_ep *dep,
if ((i == remaining - 1) || !length)
last_sg = true;
- if (!dwc3_calc_trbs_left(dep))
+ if (!num_trbs_left)
break;
if (last_sg) {
@@ -1196,12 +1196,13 @@ static int dwc3_prepare_trbs_sg(struct dwc3_ep *dep,
} else {
/*
* Look ahead to check if we have enough TRBs for the
- * last SG entry. If not, set interrupt on this TRB to
- * resume preparing the last SG entry when more TRBs are
+ * next SG entry. If not, set interrupt on this TRB to
+ * resume preparing the next SG entry when more TRBs are
* free.
*/
- if (needs_extra_trb && dwc3_calc_trbs_left(dep) <= 2 &&
- sg_dma_len(sg_next(s)) >= length)
+ if (num_trbs_left == 1 || (needs_extra_trb &&
+ num_trbs_left <= 2 &&
+ sg_dma_len(sg_next(s)) >= length))
must_interrupt = true;
dwc3_prepare_one_trb(dep, req, trb_length, 1, i, false,
@@ -1230,7 +1231,7 @@ static int dwc3_prepare_trbs_sg(struct dwc3_ep *dep,
break;
}
- if (!dwc3_calc_trbs_left(dep) || must_interrupt)
+ if (must_interrupt)
break;
}
To keep the setting of interrupt-on-completion (IOC) when out of TRBs consistent and easier to read, the caller of dwc3_prepare_one_trb() will determine if the TRB must have IOC bit set. This also reduces the number of times we need to call dwc3_calc_trbs_left(). Note that we only care about setting IOC from insufficient number of TRBs for SG and not linear requests (because we don't need to split linear requests). Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com> --- drivers/usb/dwc3/gadget.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-)