[PATCH 4.16 073/161] usb: dwc2: hcd: Fix host channel halt flow

[Greg Kroah-Hartman]

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

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

From: Minas Harutyunyan <hminas@xxxxxxxxxxxx>

[ Upstream commit a82c7abdf8fc3b09c4a0ed2eee6d43ecef2ccdb0 ]

According databook in Buffer and External DMA mode
non-split periodic channels can't be halted.

Acked-by: John Youn <johnyoun@xxxxxxxxxxxx>
Signed-off-by: Minas Harutyunyan <hminas@xxxxxxxxxxxx>
Signed-off-by: Grigor Tovmasyan <tovmasya@xxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/usb/dwc2/hcd.c |   18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -989,6 +989,24 @@ void dwc2_hc_halt(struct dwc2_hsotg *hso
 
 	if (dbg_hc(chan))
 		dev_vdbg(hsotg->dev, "%s()\n", __func__);
+
+	/*
+	 * In buffer DMA or external DMA mode channel can't be halted
+	 * for non-split periodic channels. At the end of the next
+	 * uframe/frame (in the worst case), the core generates a channel
+	 * halted and disables the channel automatically.
+	 */
+	if ((hsotg->params.g_dma && !hsotg->params.g_dma_desc) ||
+	    hsotg->hw_params.arch == GHWCFG2_EXT_DMA_ARCH) {
+		if (!chan->do_split &&
+		    (chan->ep_type == USB_ENDPOINT_XFER_ISOC ||
+		     chan->ep_type == USB_ENDPOINT_XFER_INT)) {
+			dev_err(hsotg->dev, "%s() Channel can't be halted\n",
+				__func__);
+			return;
+		}
+	}
+
 	if (halt_status == DWC2_HC_XFER_NO_HALT_STATUS)
 		dev_err(hsotg->dev, "!!! halt_status = %d !!!\n", halt_status);