commit aa9506e92bfb02a695a62dee03df46058af97c2b
author Stefan Brüns <stefan.bruens@rwth-aachen.de> Sun Jan 17 04:09:52 2016 +0100
committer Marek Vasut <marex@denx.de> Sat Jan 23 16:21:11 2016 +0100
tree 2b4af296df82e98310d1f9fa7ecfc5c787620b25
parent 575b0ebc9ddd819826dddf71861af9af3778aa49

usb: dwc2: Simplify wait_for_chhltd(), remove ignore_ack

A transfer is completed if the XFERCOMP flag is set, irrespective of the
ACK flag. BULK OUT transfers to some HS devices complete without having
the ACK flag set, which signal the devices has responded with an NYET
to the transfer (PING protocol).
The new behaviour matches the Linux kernel minus any PING protocol.

Also see 5966defabdcc (usb: dwc2: fix bulk transfers)

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>

drivers/usb/host/dwc2.c

diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c
index d317104..ad097cb 100644
--- a/drivers/usb/host/dwc2.c
+++ b/drivers/usb/host/dwc2.c
@@ -729,10 +729,8 @@
 	return stat;
 }
 
-int wait_for_chhltd(struct dwc2_core_regs *regs, uint32_t *sub, int *toggle,
-		    bool ignore_ack)
+int wait_for_chhltd(struct dwc2_core_regs *regs, uint32_t *sub, int *toggle)
 {
-	uint32_t hcint_comp_hlt_ack = DWC2_HCINT_XFERCOMP | DWC2_HCINT_CHHLTD;
 	struct dwc2_hc_regs *hc_regs = &regs->hc_regs[DWC2_HC_CHANNEL];
 	int ret;
 	uint32_t hcint, hctsiz;
@@ -742,25 +740,22 @@
 		return ret;
 
 	hcint = readl(&hc_regs->hcint);
-	if (hcint & (DWC2_HCINT_NAK | DWC2_HCINT_FRMOVRUN))
-		return -EAGAIN;
-	if (ignore_ack)
-		hcint &= ~DWC2_HCINT_ACK;
-	else
-		hcint_comp_hlt_ack |= DWC2_HCINT_ACK;
-	if (hcint != hcint_comp_hlt_ack) {
-		debug("%s: Error (HCINT=%08x)\n", __func__, hcint);
-		return -EINVAL;
-	}
-
 	hctsiz = readl(&hc_regs->hctsiz);
 	*sub = (hctsiz & DWC2_HCTSIZ_XFERSIZE_MASK) >>
 		DWC2_HCTSIZ_XFERSIZE_OFFSET;
 	*toggle = (hctsiz & DWC2_HCTSIZ_PID_MASK) >> DWC2_HCTSIZ_PID_OFFSET;
 
+	debug("%s: HCINT=%08x sub=%u toggle=%d\n", __func__, hcint, *sub,
+	      *toggle);
+
-	debug("%s: sub=%u toggle=%d\n", __func__, *sub, *toggle);
+	if (hcint & DWC2_HCINT_XFERCOMP)
+		return 0;
+
+	if (hcint & (DWC2_HCINT_NAK | DWC2_HCINT_FRMOVRUN))
+		return -EAGAIN;
 
-	return 0;
+	debug("%s: Error (HCINT=%08x)\n", __func__, hcint);
+	return -EINVAL;
 }
 
 static int dwc2_eptype[] = {
@@ -771,8 +766,7 @@
 };
 
 int chunk_msg(struct dwc2_priv *priv, struct usb_device *dev,
-	      unsigned long pipe, int *pid, int in, void *buffer, int len,
-	      bool ignore_ack)
+	      unsigned long pipe, int *pid, int in, void *buffer, int len)
 {
 	struct dwc2_core_regs *regs = priv->regs;
 	struct dwc2_hc_regs *hc_regs = &regs->hc_regs[DWC2_HC_CHANNEL];
@@ -841,7 +835,7 @@
 				(1 << DWC2_HCCHAR_MULTICNT_OFFSET) |
 				DWC2_HCCHAR_CHEN);
 
-		ret = wait_for_chhltd(regs, &sub, pid, ignore_ack);
+		ret = wait_for_chhltd(regs, &sub, pid);
 		if (ret)
 			break;
 
@@ -883,7 +877,7 @@
 	}
 
 	return chunk_msg(priv, dev, pipe, &priv->bulk_data_toggle[devnum][ep],
-			 usb_pipein(pipe), buffer, len, true);
+			 usb_pipein(pipe), buffer, len);
 }
 
 static int _submit_control_msg(struct dwc2_priv *priv, struct usb_device *dev,
@@ -903,14 +897,14 @@
 	}
 
 	pid = DWC2_HC_PID_SETUP;
-	ret = chunk_msg(priv, dev, pipe, &pid, 0, setup, 8, true);
+	ret = chunk_msg(priv, dev, pipe, &pid, 0, setup, 8);
 	if (ret)
 		return ret;
 
 	if (buffer) {
 		pid = DWC2_HC_PID_DATA1;
 		ret = chunk_msg(priv, dev, pipe, &pid, usb_pipein(pipe), buffer,
-				len, false);
+				len);
 		if (ret)
 			return ret;
 		act_len = dev->act_len;
@@ -926,7 +920,7 @@
 
 	pid = DWC2_HC_PID_DATA1;
 	ret = chunk_msg(priv, dev, pipe, &pid, status_direction,
-			priv->status_buffer, 0, false);
+			priv->status_buffer, 0);
 	if (ret)
 		return ret;