[U-Boot] [PATCH v2 15/18] usb: cmd: Print actual packet size for super speed devices

Bin Meng bmeng.cn at gmail.com
Thu Jun 22 07:14:09 UTC 2017


USB 3.0 defines bMaxPacketSize0 field in the device descriptor as
the exponent of 2, so let's print the calculated actual size.

Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
Reviewed-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Stefan Roese <sr at denx.de>
Tested-by: Stefan Roese <sr at denx.de>

---

Changes in v2:
- Change to use uint and also 'normal' variable name packet_size.

 cmd/usb.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/cmd/usb.c b/cmd/usb.c
index 4fa456e..992d414 100644
--- a/cmd/usb.c
+++ b/cmd/usb.c
@@ -150,6 +150,8 @@ static void usb_display_string(struct usb_device *dev, int index)
 
 static void usb_display_desc(struct usb_device *dev)
 {
+	uint packet_size = dev->descriptor.bMaxPacketSize0;
+
 	if (dev->descriptor.bDescriptorType == USB_DT_DEVICE) {
 		printf("%d: %s,  USB Revision %x.%x\n", dev->devnum,
 		usb_get_class_desc(dev->config.if_desc[0].desc.bInterfaceClass),
@@ -171,9 +173,10 @@ static void usb_display_desc(struct usb_device *dev)
 			       usb_get_class_desc(
 				dev->config.if_desc[0].desc.bInterfaceClass));
 		}
+		if (dev->descriptor.bcdUSB >= cpu_to_le16(0x0300))
+			packet_size = 1 << packet_size;
 		printf(" - PacketSize: %d  Configurations: %d\n",
-			dev->descriptor.bMaxPacketSize0,
-			dev->descriptor.bNumConfigurations);
+			packet_size, dev->descriptor.bNumConfigurations);
 		printf(" - Vendor: 0x%04x  Product 0x%04x Version %d.%d\n",
 			dev->descriptor.idVendor, dev->descriptor.idProduct,
 			(dev->descriptor.bcdDevice>>8) & 0xff,
-- 
2.9.2



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