Revert "USB: core: Unite old scheme and new scheme descriptor reads"

This reverts commit 56c49a3328e988c82981f4d098be22695d46fcf3.

Downstream NXP and stable have deviated to far, do not pull this in.

Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>

1 files changed, 79 insertions, 94 deletions

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index fa8683c448c9..2295d69b4cd2 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -4666,67 +4666,6 @@ static int hub_enable_device(struct usb_device *udev)
 	return hcd->driver->enable_device(hcd, udev);
 }
 
-/*
- * Get the bMaxPacketSize0 value during initialization by reading the
- * device's device descriptor.  Since we don't already know this value,
- * the transfer is unsafe and it ignores I/O errors, only testing for
- * reasonable received values.
- *
- * For "old scheme" initialization, size will be 8 so we read just the
- * start of the device descriptor, which should work okay regardless of
- * the actual bMaxPacketSize0 value.  For "new scheme" initialization,
- * size will be 64 (and buf will point to a sufficiently large buffer),
- * which might not be kosher according to the USB spec but it's what
- * Windows does and what many devices expect.
- *
- * Returns: bMaxPacketSize0 or a negative error code.
- */
-static int get_bMaxPacketSize0(struct usb_device *udev,
-		struct usb_device_descriptor *buf, int size, bool first_time)
-{
-	int i, rc;
-
-	/*
-	 * Retry on all errors; some devices are flakey.
-	 * 255 is for WUSB devices, we actually need to use
-	 * 512 (WUSB1.0[4.8.1]).
-	 */
-	for (i = 0; i < GET_MAXPACKET0_TRIES; ++i) {
-		/* Start with invalid values in case the transfer fails */
-		buf->bDescriptorType = buf->bMaxPacketSize0 = 0;
-		rc = usb_control_msg(udev, usb_rcvaddr0pipe(),
-				USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
-				USB_DT_DEVICE << 8, 0,
-				buf, size,
-				initial_descriptor_timeout);
-		switch (buf->bMaxPacketSize0) {
-		case 8: case 16: case 32: case 64: case 255:
-			if (buf->bDescriptorType == USB_DT_DEVICE) {
-				rc = buf->bMaxPacketSize0;
-				break;
-			}
-			fallthrough;
-		default:
-			if (rc >= 0)
-				rc = -EPROTO;
-			break;
-		}
-
-		/*
-		 * Some devices time out if they are powered on
-		 * when already connected. They need a second
-		 * reset, so return early. But only on the first
-		 * attempt, lest we get into a time-out/reset loop.
-		 */
-		if (rc > 0 || (rc == -ETIMEDOUT && first_time &&
-				udev->speed > USB_SPEED_FULL))
-			break;
-	}
-	return rc;
-}
-
-#define GET_DESCRIPTOR_BUFSIZE	64
-
 /* Reset device, (re)assign address, get device descriptor.
  * Device connection must be stable, no more debouncing needed.
  * Returns device in USB_STATE_ADDRESS, except on error.
@@ -4751,12 +4690,6 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
 	int			devnum = udev->devnum;
 	const char		*driver_name;
 	bool			do_new_scheme;
-	int			maxp0;
-	struct usb_device_descriptor	*buf;
-
-	buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
-	if (!buf)
-		return -ENOMEM;
 
 	/* root hub ports have a slightly longer reset period
 	 * (from USB 2.0 spec, section 7.1.7.5)
@@ -4871,6 +4804,9 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
 
 	for (retries = 0; retries < GET_DESCRIPTOR_TRIES; (++retries, msleep(100))) {
 		if (do_new_scheme) {
+			struct usb_device_descriptor *buf;
+			int r = 0;
+
 			retval = hub_enable_device(udev);
 			if (retval < 0) {
 				dev_err(&udev->dev,
@@ -4879,8 +4815,52 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
 				goto fail;
 			}
 
-			maxp0 = get_bMaxPacketSize0(udev, buf,
-					GET_DESCRIPTOR_BUFSIZE, retries == 0);
+#define GET_DESCRIPTOR_BUFSIZE	64
+			buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
+			if (!buf) {
+				retval = -ENOMEM;
+				continue;
+			}
+
+			/* Retry on all errors; some devices are flakey.
+			 * 255 is for WUSB devices, we actually need to use
+			 * 512 (WUSB1.0[4.8.1]).
+			 */
+			for (operations = 0; operations < GET_MAXPACKET0_TRIES;
+					++operations) {
+				buf->bMaxPacketSize0 = 0;
+				r = usb_control_msg(udev, usb_rcvaddr0pipe(),
+					USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
+					USB_DT_DEVICE << 8, 0,
+					buf, GET_DESCRIPTOR_BUFSIZE,
+					initial_descriptor_timeout);
+				switch (buf->bMaxPacketSize0) {
+				case 8: case 16: case 32: case 64: case 255:
+					if (buf->bDescriptorType ==
+							USB_DT_DEVICE) {
+						r = 0;
+						break;
+					}
+					fallthrough;
+				default:
+					if (r == 0)
+						r = -EPROTO;
+					break;
+				}
+				/*
+				 * Some devices time out if they are powered on
+				 * when already connected. They need a second
+				 * reset. But only on the first attempt,
+				 * lest we get into a time out/reset loop
+				 */
+				if (r == 0 || (r == -ETIMEDOUT &&
+						retries == 0 &&
+						udev->speed > USB_SPEED_FULL))
+					break;
+			}
+			udev->descriptor.bMaxPacketSize0 =
+					buf->bMaxPacketSize0;
+			kfree(buf);
 
 			retval = hub_port_reset(hub, port1, udev, delay, false);
 			if (retval < 0)		/* error or disconnect */
@@ -4891,13 +4871,14 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
 				retval = -ENODEV;
 				goto fail;
 			}
-			if (maxp0 < 0) {
-				if (maxp0 != -ENODEV)
+			if (r) {
+				if (r != -ENODEV)
 					dev_err(&udev->dev, "device descriptor read/64, error %d\n",
-							maxp0);
-				retval = maxp0;
+							r);
+				retval = -EMSGSIZE;
 				continue;
 			}
+#undef GET_DESCRIPTOR_BUFSIZE
 		}
 
 		/*
@@ -4943,17 +4924,19 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
 				break;
 		}
 
-		/* !do_new_scheme || wusb */
-		maxp0 = get_bMaxPacketSize0(udev, buf, 8, retries == 0);
-		if (maxp0 < 0) {
-			retval = maxp0;
+		retval = usb_get_device_descriptor(udev, 8);
+		if (retval < 8) {
 			if (retval != -ENODEV)
 				dev_err(&udev->dev,
 					"device descriptor read/8, error %d\n",
 					retval);
+			if (retval >= 0)
+				retval = -EMSGSIZE;
 		} else {
 			u32 delay;
 
+			retval = 0;
+
 			delay = udev->parent->hub_delay;
 			udev->hub_delay = min_t(u32, delay,
 						USB_TP_TRANSMISSION_DELAY_MAX);
@@ -4970,10 +4953,27 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
 	if (retval)
 		goto fail;
 
-	if (maxp0 == 0xff || udev->speed >= USB_SPEED_SUPER)
+	/*
+	 * Some superspeed devices have finished the link training process
+	 * and attached to a superspeed hub port, but the device descriptor
+	 * got from those devices show they aren't superspeed devices. Warm
+	 * reset the port attached by the devices can fix them.
+	 */
+	if ((udev->speed >= USB_SPEED_SUPER) &&
+			(le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
+		dev_err(&udev->dev, "got a wrong device descriptor, "
+				"warm reset device\n");
+		hub_port_reset(hub, port1, udev,
+				HUB_BH_RESET_TIME, true);
+		retval = -EINVAL;
+		goto fail;
+	}
+
+	if (udev->descriptor.bMaxPacketSize0 == 0xff ||
+			udev->speed >= USB_SPEED_SUPER)
 		i = 512;
 	else
-		i = maxp0;
+		i = udev->descriptor.bMaxPacketSize0;
 	if (usb_endpoint_maxp(&udev->ep0.desc) != i) {
 		if (udev->speed == USB_SPEED_LOW ||
 				!(i == 8 || i == 16 || i == 32 || i == 64)) {
@@ -4999,20 +4999,6 @@ hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
 		goto fail;
 	}
 
-	/*
-	 * Some superspeed devices have finished the link training process
-	 * and attached to a superspeed hub port, but the device descriptor
-	 * got from those devices show they aren't superspeed devices. Warm
-	 * reset the port attached by the devices can fix them.
-	 */
-	if ((udev->speed >= USB_SPEED_SUPER) &&
-			(le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
-		dev_err(&udev->dev, "got a wrong device descriptor, warm reset device\n");
-		hub_port_reset(hub, port1, udev, HUB_BH_RESET_TIME, true);
-		retval = -EINVAL;
-		goto fail;
-	}
-
 	usb_detect_quirks(udev);
 
 	if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
@@ -5033,7 +5019,6 @@ fail:
 		hub_port_disable(hub, port1, 0);
 		update_devnum(udev, devnum);	/* for disconnect processing */
 	}
-	kfree(buf);
 	return retval;
 }