Merge tag 'fixes-for-v4.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-linus

Felipe writes:

usb: fixes for v4.18-rc5

With a total of 20 non-merge commits, we have accumulated quite a few
fixes. These include lot's of fixes the our audio gadget interface, a
build error fix for PPC64 builds for the frescale PHY driver,
sleep-while-atomic fixes on the r8a66597 UDC driver, 3-stage SETUP fix
for the aspeed-vhub UDC and some other misc fixes.

12 files changed, 146 insertions, 107 deletions

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index a0f82cca2d9a..cefc99ae69b2 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -3430,7 +3430,7 @@ static void dwc2_gadget_handle_incomplete_isoc_in(struct dwc2_hsotg *hsotg)
 	for (idx = 1; idx < hsotg->num_of_eps; idx++) {
 		hs_ep = hsotg->eps_in[idx];
 		/* Proceed only unmasked ISOC EPs */
-		if (!hs_ep->isochronous || (BIT(idx) & ~daintmsk))
+		if ((BIT(idx) & ~daintmsk) || !hs_ep->isochronous)
 			continue;
 
 		epctrl = dwc2_readl(hsotg->regs + DIEPCTL(idx));
@@ -3476,7 +3476,7 @@ static void dwc2_gadget_handle_incomplete_isoc_out(struct dwc2_hsotg *hsotg)
 	for (idx = 1; idx < hsotg->num_of_eps; idx++) {
 		hs_ep = hsotg->eps_out[idx];
 		/* Proceed only unmasked ISOC EPs */
-		if (!hs_ep->isochronous || (BIT(idx) & ~daintmsk))
+		if ((BIT(idx) & ~daintmsk) || !hs_ep->isochronous)
 			continue;
 
 		epctrl = dwc2_readl(hsotg->regs + DOEPCTL(idx));
@@ -3650,7 +3650,7 @@ irq_retry:
 		for (idx = 1; idx < hsotg->num_of_eps; idx++) {
 			hs_ep = hsotg->eps_out[idx];
 			/* Proceed only unmasked ISOC EPs */
-			if (!hs_ep->isochronous || (BIT(idx) & ~daintmsk))
+			if ((BIT(idx) & ~daintmsk) || !hs_ep->isochronous)
 				continue;
 
 			epctrl = dwc2_readl(hsotg->regs + DOEPCTL(idx));
diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index b1104be3429c..6e2cdd7b93d4 100644
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -2665,34 +2665,35 @@ static int dwc2_alloc_split_dma_aligned_buf(struct dwc2_hsotg *hsotg,
 
 #define DWC2_USB_DMA_ALIGN 4
 
-struct dma_aligned_buffer {
-	void *kmalloc_ptr;
-	void *old_xfer_buffer;
-	u8 data[0];
-};
-
 static void dwc2_free_dma_aligned_buffer(struct urb *urb)
 {
-	struct dma_aligned_buffer *temp;
+	void *stored_xfer_buffer;
+	size_t length;
 
 	if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
 		return;
 
-	temp = container_of(urb->transfer_buffer,
-			    struct dma_aligned_buffer, data);
+	/* Restore urb->transfer_buffer from the end of the allocated area */
+	memcpy(&stored_xfer_buffer, urb->transfer_buffer +
+	       urb->transfer_buffer_length, sizeof(urb->transfer_buffer));
 
-	if (usb_urb_dir_in(urb))
-		memcpy(temp->old_xfer_buffer, temp->data,
-		       urb->transfer_buffer_length);
-	urb->transfer_buffer = temp->old_xfer_buffer;
-	kfree(temp->kmalloc_ptr);
+	if (usb_urb_dir_in(urb)) {
+		if (usb_pipeisoc(urb->pipe))
+			length = urb->transfer_buffer_length;
+		else
+			length = urb->actual_length;
+
+		memcpy(stored_xfer_buffer, urb->transfer_buffer, length);
+	}
+	kfree(urb->transfer_buffer);
+	urb->transfer_buffer = stored_xfer_buffer;
 
 	urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
 }
 
 static int dwc2_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
 {
-	struct dma_aligned_buffer *temp, *kmalloc_ptr;
+	void *kmalloc_ptr;
 	size_t kmalloc_size;
 
 	if (urb->num_sgs || urb->sg ||
@@ -2700,22 +2701,29 @@ static int dwc2_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
 	    !((uintptr_t)urb->transfer_buffer & (DWC2_USB_DMA_ALIGN - 1)))
 		return 0;
 
-	/* Allocate a buffer with enough padding for alignment */
+	/*
+	 * Allocate a buffer with enough padding for original transfer_buffer
+	 * pointer. This allocation is guaranteed to be aligned properly for
+	 * DMA
+	 */
 	kmalloc_size = urb->transfer_buffer_length +
-		sizeof(struct dma_aligned_buffer) + DWC2_USB_DMA_ALIGN - 1;
+		sizeof(urb->transfer_buffer);
 
 	kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
 	if (!kmalloc_ptr)
 		return -ENOMEM;
 
-	/* Position our struct dma_aligned_buffer such that data is aligned */
-	temp = PTR_ALIGN(kmalloc_ptr + 1, DWC2_USB_DMA_ALIGN) - 1;
-	temp->kmalloc_ptr = kmalloc_ptr;
-	temp->old_xfer_buffer = urb->transfer_buffer;
+	/*
+	 * Position value of original urb->transfer_buffer pointer to the end
+	 * of allocation for later referencing
+	 */
+	memcpy(kmalloc_ptr + urb->transfer_buffer_length,
+	       &urb->transfer_buffer, sizeof(urb->transfer_buffer));
+
 	if (usb_urb_dir_out(urb))
-		memcpy(temp->data, urb->transfer_buffer,
+		memcpy(kmalloc_ptr, urb->transfer_buffer,
 		       urb->transfer_buffer_length);
-	urb->transfer_buffer = temp->data;
+	urb->transfer_buffer = kmalloc_ptr;
 
 	urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;
 
diff --git a/drivers/usb/dwc2/hcd_intr.c b/drivers/usb/dwc2/hcd_intr.c
index ed7f05cf4906..8ce10caf3e19 100644
--- a/drivers/usb/dwc2/hcd_intr.c
+++ b/drivers/usb/dwc2/hcd_intr.c
@@ -1231,7 +1231,10 @@ static void dwc2_hc_nak_intr(struct dwc2_hsotg *hsotg,
 	 * avoid interrupt storms we'll wait before retrying if we've got
 	 * several NAKs. If we didn't do this we'd retry directly from the
 	 * interrupt handler and could end up quickly getting another
-	 * interrupt (another NAK), which we'd retry.
+	 * interrupt (another NAK), which we'd retry. Note that we do not
+	 * delay retries for IN parts of control requests, as those are expected
+	 * to complete fairly quickly, and if we delay them we risk confusing
+	 * the device and cause it issue STALL.
 	 *
 	 * Note that in DMA mode software only gets involved to re-send NAKed
 	 * transfers for split transactions, so we only need to apply this
@@ -1244,7 +1247,9 @@ static void dwc2_hc_nak_intr(struct dwc2_hsotg *hsotg,
 			qtd->error_count = 0;
 		qtd->complete_split = 0;
 		qtd->num_naks++;
-		qtd->qh->want_wait = qtd->num_naks >= DWC2_NAKS_BEFORE_DELAY;
+		qtd->qh->want_wait = qtd->num_naks >= DWC2_NAKS_BEFORE_DELAY &&
+				!(chan->ep_type == USB_ENDPOINT_XFER_CONTROL &&
+				  chan->ep_is_in);
 		dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_NAK);
 		goto handle_nak_done;
 	}
diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index c77ff50a88a2..8efde178eef4 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -973,15 +973,12 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
 		ret = dwc3_ep0_start_trans(dep);
 	} else if (IS_ALIGNED(req->request.length, dep->endpoint.maxpacket) &&
 		   req->request.length && req->request.zero) {
-		u32	maxpacket;
 
 		ret = usb_gadget_map_request_by_dev(dwc->sysdev,
 				&req->request, dep->number);
 		if (ret)
 			return;
 
-		maxpacket = dep->endpoint.maxpacket;
-
 		/* prepare normal TRB */
 		dwc3_ep0_prepare_one_trb(dep, req->request.dma,
 					 req->request.length,
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index d2fa071c21b1..b8a15840b4ff 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -1819,7 +1819,6 @@ unknown:
 		if (cdev->use_os_string && cdev->os_desc_config &&
 		    (ctrl->bRequestType & USB_TYPE_VENDOR) &&
 		    ctrl->bRequest == cdev->b_vendor_code) {
-			struct usb_request		*req;
 			struct usb_configuration	*os_desc_cfg;
 			u8				*buf;
 			int				interface;
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index d2dc1f00180b..d582921f7257 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -438,14 +438,14 @@ static struct usb_descriptor_header *hs_audio_desc[] = {
 };
 
 struct cntrl_cur_lay3 {
-	__u32	dCUR;
+	__le32	dCUR;
 };
 
 struct cntrl_range_lay3 {
-	__u16	wNumSubRanges;
-	__u32	dMIN;
-	__u32	dMAX;
-	__u32	dRES;
+	__le16	wNumSubRanges;
+	__le32	dMIN;
+	__le32	dMAX;
+	__le32	dRES;
 } __packed;
 
 static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
@@ -559,13 +559,13 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 	agdev->out_ep = usb_ep_autoconfig(gadget, &fs_epout_desc);
 	if (!agdev->out_ep) {
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
-		return ret;
+		return -ENODEV;
 	}
 
 	agdev->in_ep = usb_ep_autoconfig(gadget, &fs_epin_desc);
 	if (!agdev->in_ep) {
 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
-		return ret;
+		return -ENODEV;
 	}
 
 	agdev->in_ep_maxpsize = max_t(u16,
@@ -703,9 +703,9 @@ in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 		memset(&c, 0, sizeof(struct cntrl_cur_lay3));
 
 		if (entity_id == USB_IN_CLK_ID)
-			c.dCUR = p_srate;
+			c.dCUR = cpu_to_le32(p_srate);
 		else if (entity_id == USB_OUT_CLK_ID)
-			c.dCUR = c_srate;
+			c.dCUR = cpu_to_le32(c_srate);
 
 		value = min_t(unsigned, w_length, sizeof c);
 		memcpy(req->buf, &c, value);
@@ -742,15 +742,15 @@ in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
 
 	if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
 		if (entity_id == USB_IN_CLK_ID)
-			r.dMIN = p_srate;
+			r.dMIN = cpu_to_le32(p_srate);
 		else if (entity_id == USB_OUT_CLK_ID)
-			r.dMIN = c_srate;
+			r.dMIN = cpu_to_le32(c_srate);
 		else
 			return -EOPNOTSUPP;
 
 		r.dMAX = r.dMIN;
 		r.dRES = 0;
-		r.wNumSubRanges = 1;
+		r.wNumSubRanges = cpu_to_le16(1);
 
 		value = min_t(unsigned, w_length, sizeof r);
 		memcpy(req->buf, &r, value);
diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c
index a72295c953bb..fb5ed97572e5 100644
--- a/drivers/usb/gadget/function/u_audio.c
+++ b/drivers/usb/gadget/function/u_audio.c
@@ -32,9 +32,6 @@ struct uac_req {
 struct uac_rtd_params {
 	struct snd_uac_chip *uac; /* parent chip */
 	bool ep_enabled; /* if the ep is enabled */
-	/* Size of the ring buffer */
-	size_t dma_bytes;
-	unsigned char *dma_area;
 
 	struct snd_pcm_substream *ss;
 
@@ -43,8 +40,6 @@ struct uac_rtd_params {
 
 	void *rbuf;
 
-	size_t period_size;
-
 	unsigned max_psize;	/* MaxPacketSize of endpoint */
 	struct uac_req *ureq;
 
@@ -84,12 +79,12 @@ static const struct snd_pcm_hardware uac_pcm_hardware = {
 static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
 {
 	unsigned pending;
-	unsigned long flags;
+	unsigned long flags, flags2;
 	unsigned int hw_ptr;
-	bool update_alsa = false;
 	int status = req->status;
 	struct uac_req *ur = req->context;
 	struct snd_pcm_substream *substream;
+	struct snd_pcm_runtime *runtime;
 	struct uac_rtd_params *prm = ur->pp;
 	struct snd_uac_chip *uac = prm->uac;
 
@@ -111,6 +106,14 @@ static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
 	if (!substream)
 		goto exit;
 
+	snd_pcm_stream_lock_irqsave(substream, flags2);
+
+	runtime = substream->runtime;
+	if (!runtime || !snd_pcm_running(substream)) {
+		snd_pcm_stream_unlock_irqrestore(substream, flags2);
+		goto exit;
+	}
+
 	spin_lock_irqsave(&prm->lock, flags);
 
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
@@ -137,43 +140,46 @@ static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
 		req->actual = req->length;
 	}
 
-	pending = prm->hw_ptr % prm->period_size;
-	pending += req->actual;
-	if (pending >= prm->period_size)
-		update_alsa = true;
-
 	hw_ptr = prm->hw_ptr;
-	prm->hw_ptr = (prm->hw_ptr + req->actual) % prm->dma_bytes;
 
 	spin_unlock_irqrestore(&prm->lock, flags);
 
 	/* Pack USB load in ALSA ring buffer */
-	pending = prm->dma_bytes - hw_ptr;
+	pending = runtime->dma_bytes - hw_ptr;
 
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 		if (unlikely(pending < req->actual)) {
-			memcpy(req->buf, prm->dma_area + hw_ptr, pending);
-			memcpy(req->buf + pending, prm->dma_area,
+			memcpy(req->buf, runtime->dma_area + hw_ptr, pending);
+			memcpy(req->buf + pending, runtime->dma_area,
 			       req->actual - pending);
 		} else {
-			memcpy(req->buf, prm->dma_area + hw_ptr, req->actual);
+			memcpy(req->buf, runtime->dma_area + hw_ptr,
+			       req->actual);
 		}
 	} else {
 		if (unlikely(pending < req->actual)) {
-			memcpy(prm->dma_area + hw_ptr, req->buf, pending);
-			memcpy(prm->dma_area, req->buf + pending,
+			memcpy(runtime->dma_area + hw_ptr, req->buf, pending);
+			memcpy(runtime->dma_area, req->buf + pending,
 			       req->actual - pending);
 		} else {
-			memcpy(prm->dma_area + hw_ptr, req->buf, req->actual);
+			memcpy(runtime->dma_area + hw_ptr, req->buf,
+			       req->actual);
 		}
 	}
 
+	spin_lock_irqsave(&prm->lock, flags);
+	/* update hw_ptr after data is copied to memory */
+	prm->hw_ptr = (hw_ptr + req->actual) % runtime->dma_bytes;
+	hw_ptr = prm->hw_ptr;
+	spin_unlock_irqrestore(&prm->lock, flags);
+	snd_pcm_stream_unlock_irqrestore(substream, flags2);
+
+	if ((hw_ptr % snd_pcm_lib_period_bytes(substream)) < req->actual)
+		snd_pcm_period_elapsed(substream);
+
 exit:
 	if (usb_ep_queue(ep, req, GFP_ATOMIC))
 		dev_err(uac->card->dev, "%d Error!\n", __LINE__);
-
-	if (update_alsa)
-		snd_pcm_period_elapsed(substream);
 }
 
 static int uac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
@@ -236,40 +242,12 @@ static snd_pcm_uframes_t uac_pcm_pointer(struct snd_pcm_substream *substream)
 static int uac_pcm_hw_params(struct snd_pcm_substream *substream,
 			       struct snd_pcm_hw_params *hw_params)
 {
-	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
-	struct uac_rtd_params *prm;
-	int err;
-
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
-		prm = &uac->p_prm;
-	else
-		prm = &uac->c_prm;
-
-	err = snd_pcm_lib_malloc_pages(substream,
+	return snd_pcm_lib_malloc_pages(substream,
 					params_buffer_bytes(hw_params));
-	if (err >= 0) {
-		prm->dma_bytes = substream->runtime->dma_bytes;
-		prm->dma_area = substream->runtime->dma_area;
-		prm->period_size = params_period_bytes(hw_params);
-	}
-
-	return err;
 }
 
 static int uac_pcm_hw_free(struct snd_pcm_substream *substream)
 {
-	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
-	struct uac_rtd_params *prm;
-
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
-		prm = &uac->p_prm;
-	else
-		prm = &uac->c_prm;
-
-	prm->dma_area = NULL;
-	prm->dma_bytes = 0;
-	prm->period_size = 0;
-
 	return snd_pcm_lib_free_pages(substream);
 }
 
@@ -595,15 +573,15 @@ int g_audio_setup(struct g_audio *g_audio, const char *pcm_name,
 	if (err < 0)
 		goto snd_fail;
 
-	strcpy(pcm->name, pcm_name);
+	strlcpy(pcm->name, pcm_name, sizeof(pcm->name));
 	pcm->private_data = uac;
 	uac->pcm = pcm;
 
 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &uac_pcm_ops);
 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &uac_pcm_ops);
 
-	strcpy(card->driver, card_name);
-	strcpy(card->shortname, card_name);
+	strlcpy(card->driver, card_name, sizeof(card->driver));
+	strlcpy(card->shortname, card_name, sizeof(card->shortname));
 	sprintf(card->longname, "%s %i", card_name, card->dev->id);
 
 	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/ep0.c b/drivers/usb/gadget/udc/aspeed-vhub/ep0.c
index 20ffb03ff6ac..e2927fb083cf 100644
--- a/drivers/usb/gadget/udc/aspeed-vhub/ep0.c
+++ b/drivers/usb/gadget/udc/aspeed-vhub/ep0.c
@@ -108,6 +108,13 @@ void ast_vhub_ep0_handle_setup(struct ast_vhub_ep *ep)
 	/* Check our state, cancel pending requests if needed */
 	if (ep->ep0.state != ep0_state_token) {
 		EPDBG(ep, "wrong state\n");
+		ast_vhub_nuke(ep, -EIO);
+
+		/*
+		 * Accept the packet regardless, this seems to happen
+		 * when stalling a SETUP packet that has an OUT data
+		 * phase.
+		 */
 		ast_vhub_nuke(ep, 0);
 		goto stall;
 	}
@@ -212,6 +219,8 @@ static void ast_vhub_ep0_do_send(struct ast_vhub_ep *ep,
 	if (chunk && req->req.buf)
 		memcpy(ep->buf, req->req.buf + req->req.actual, chunk);
 
+	vhub_dma_workaround(ep->buf);
+
 	/* Remember chunk size and trigger send */
 	reg = VHUB_EP0_SET_TX_LEN(chunk);
 	writel(reg, ep->ep0.ctlstat);
@@ -224,7 +233,7 @@ static void ast_vhub_ep0_rx_prime(struct ast_vhub_ep *ep)
 	EPVDBG(ep, "rx prime\n");
 
 	/* Prime endpoint for receiving data */
-	writel(VHUB_EP0_RX_BUFF_RDY, ep->ep0.ctlstat + AST_VHUB_EP0_CTRL);
+	writel(VHUB_EP0_RX_BUFF_RDY, ep->ep0.ctlstat);
 }
 
 static void ast_vhub_ep0_do_receive(struct ast_vhub_ep *ep, struct ast_vhub_req *req,
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/epn.c b/drivers/usb/gadget/udc/aspeed-vhub/epn.c
index 80c9feac5147..5939eb1e97f2 100644
--- a/drivers/usb/gadget/udc/aspeed-vhub/epn.c
+++ b/drivers/usb/gadget/udc/aspeed-vhub/epn.c
@@ -66,11 +66,16 @@ static void ast_vhub_epn_kick(struct ast_vhub_ep *ep, struct ast_vhub_req *req)
 	if (!req->req.dma) {
 
 		/* For IN transfers, copy data over first */
-		if (ep->epn.is_in)
+		if (ep->epn.is_in) {
 			memcpy(ep->buf, req->req.buf + act, chunk);
+			vhub_dma_workaround(ep->buf);
+		}
 		writel(ep->buf_dma, ep->epn.regs + AST_VHUB_EP_DESC_BASE);
-	} else
+	} else {
+		if (ep->epn.is_in)
+			vhub_dma_workaround(req->req.buf);
 		writel(req->req.dma + act, ep->epn.regs + AST_VHUB_EP_DESC_BASE);
+	}
 
 	/* Start DMA */
 	req->active = true;
@@ -161,6 +166,7 @@ static inline unsigned int ast_vhub_count_free_descs(struct ast_vhub_ep *ep)
 static void ast_vhub_epn_kick_desc(struct ast_vhub_ep *ep,
 				   struct ast_vhub_req *req)
 {
+	struct ast_vhub_desc *desc = NULL;
 	unsigned int act = req->act_count;
 	unsigned int len = req->req.length;
 	unsigned int chunk;
@@ -177,7 +183,6 @@ static void ast_vhub_epn_kick_desc(struct ast_vhub_ep *ep,
 
 	/* While we can create descriptors */
 	while (ast_vhub_count_free_descs(ep) && req->last_desc < 0) {
-		struct ast_vhub_desc *desc;
 		unsigned int d_num;
 
 		/* Grab next free descriptor */
@@ -227,6 +232,9 @@ static void ast_vhub_epn_kick_desc(struct ast_vhub_ep *ep,
 		req->act_count = act = act + chunk;
 	}
 
+	if (likely(desc))
+		vhub_dma_workaround(desc);
+
 	/* Tell HW about new descriptors */
 	writel(VHUB_EP_DMA_SET_CPU_WPTR(ep->epn.d_next),
 	       ep->epn.regs + AST_VHUB_EP_DESC_STATUS);
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/vhub.h b/drivers/usb/gadget/udc/aspeed-vhub/vhub.h
index 2b040257bc1f..4ed03d33a5a9 100644
--- a/drivers/usb/gadget/udc/aspeed-vhub/vhub.h
+++ b/drivers/usb/gadget/udc/aspeed-vhub/vhub.h
@@ -462,6 +462,39 @@ enum std_req_rc {
 #define DDBG(d, fmt, ...)	do { } while(0)
 #endif
 
+static inline void vhub_dma_workaround(void *addr)
+{
+	/*
+	 * This works around a confirmed HW issue with the Aspeed chip.
+	 *
+	 * The core uses a different bus to memory than the AHB going to
+	 * the USB device controller. Due to the latter having a higher
+	 * priority than the core for arbitration on that bus, it's
+	 * possible for an MMIO to the device, followed by a DMA by the
+	 * device from memory to all be performed and services before
+	 * a previous store to memory gets completed.
+	 *
+	 * This the following scenario can happen:
+	 *
+	 *    - Driver writes to a DMA descriptor (Mbus)
+	 *    - Driver writes to the MMIO register to start the DMA (AHB)
+	 *    - The gadget sees the second write and sends a read of the
+	 *      descriptor to the memory controller (Mbus)
+	 *    - The gadget hits memory before the descriptor write
+	 *      causing it to read an obsolete value.
+	 *
+	 * Thankfully the problem is limited to the USB gadget device, other
+	 * masters in the SoC all have a lower priority than the core, thus
+	 * ensuring that the store by the core arrives first.
+	 *
+	 * The workaround consists of using a dummy read of the memory before
+	 * doing the MMIO writes. This will ensure that the previous writes
+	 * have been "pushed out".
+	 */
+	mb();
+	(void)__raw_readl((void __iomem *)addr);
+}
+
 /* core.c */
 void ast_vhub_done(struct ast_vhub_ep *ep, struct ast_vhub_req *req,
 		   int status);
diff --git a/drivers/usb/gadget/udc/r8a66597-udc.c b/drivers/usb/gadget/udc/r8a66597-udc.c
index a3ecce62662b..11e25a3f4f1f 100644
--- a/drivers/usb/gadget/udc/r8a66597-udc.c
+++ b/drivers/usb/gadget/udc/r8a66597-udc.c
@@ -832,11 +832,11 @@ static void init_controller(struct r8a66597 *r8a66597)
 
 		r8a66597_bset(r8a66597, XCKE, SYSCFG0);
 
-		msleep(3);
+		mdelay(3);
 
 		r8a66597_bset(r8a66597, PLLC, SYSCFG0);
 
-		msleep(1);
+		mdelay(1);
 
 		r8a66597_bset(r8a66597, SCKE, SYSCFG0);
 
@@ -1190,7 +1190,7 @@ __acquires(r8a66597->lock)
 	r8a66597->ep0_req->length = 2;
 	/* AV: what happens if we get called again before that gets through? */
 	spin_unlock(&r8a66597->lock);
-	r8a66597_queue(r8a66597->gadget.ep0, r8a66597->ep0_req, GFP_KERNEL);
+	r8a66597_queue(r8a66597->gadget.ep0, r8a66597->ep0_req, GFP_ATOMIC);
 	spin_lock(&r8a66597->lock);
 }
 
diff --git a/drivers/usb/phy/phy-fsl-usb.c b/drivers/usb/phy/phy-fsl-usb.c
index 900875f326d7..f7c96d209eda 100644
--- a/drivers/usb/phy/phy-fsl-usb.c
+++ b/drivers/usb/phy/phy-fsl-usb.c
@@ -861,6 +861,7 @@ int usb_otg_start(struct platform_device *pdev)
 	if (pdata->init && pdata->init(pdev) != 0)
 		return -EINVAL;
 
+#ifdef CONFIG_PPC32
 	if (pdata->big_endian_mmio) {
 		_fsl_readl = _fsl_readl_be;
 		_fsl_writel = _fsl_writel_be;
@@ -868,6 +869,7 @@ int usb_otg_start(struct platform_device *pdev)
 		_fsl_readl = _fsl_readl_le;
 		_fsl_writel = _fsl_writel_le;
 	}
+#endif
 
 	/* request irq */
 	p_otg->irq = platform_get_irq(pdev, 0);
@@ -958,7 +960,7 @@ int usb_otg_start(struct platform_device *pdev)
 /*
  * state file in sysfs
  */
-static int show_fsl_usb2_otg_state(struct device *dev,
+static ssize_t show_fsl_usb2_otg_state(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
 	struct otg_fsm *fsm = &fsl_otg_dev->fsm;