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authorBin Meng <bmeng.cn@gmail.com>2017-07-19 13:51:16 (GMT)
committerMarek Vasut <marex@denx.de>2017-07-28 21:34:34 (GMT)
commit5624dfd5aa91c244519ec60b40b4a42b4d9a43ca (patch)
treee7a0a302d46a576835159e30477071f7c599287b /common
parent493b8dd070f2412b49190b71b44baddbb2b24e37 (diff)
downloadu-boot-fsl-qoriq-5624dfd5aa91c244519ec60b40b4a42b4d9a43ca.tar.xz
usb: hub: Parse and save TT details from device descriptor
A high speed hub has a special responsibility to handle full speed/ low speed devices connected on downstream ports. In this case, the hub must isolate the high speed signaling environment from the full speed/low speed signaling environment with the help of Transaction Translator (TT). TT details are provided by hub descriptors and we parse and save it to hub uclass_priv for later use. Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'common')
-rw-r--r--common/usb_hub.c50
1 files changed, 50 insertions, 0 deletions
diff --git a/common/usb_hub.c b/common/usb_hub.c
index 18c366a..bbb1155 100644
--- a/common/usb_hub.c
+++ b/common/usb_hub.c
@@ -700,6 +700,56 @@ static int usb_hub_configure(struct usb_device *dev)
break;
}
+ switch (dev->descriptor.bDeviceProtocol) {
+ case USB_HUB_PR_FS:
+ break;
+ case USB_HUB_PR_HS_SINGLE_TT:
+ debug("Single TT\n");
+ break;
+ case USB_HUB_PR_HS_MULTI_TT:
+ ret = usb_set_interface(dev, 0, 1);
+ if (ret == 0) {
+ debug("TT per port\n");
+ hub->tt.multi = true;
+ } else {
+ debug("Using single TT (err %d)\n", ret);
+ }
+ break;
+ case USB_HUB_PR_SS:
+ /* USB 3.0 hubs don't have a TT */
+ break;
+ default:
+ debug("Unrecognized hub protocol %d\n",
+ dev->descriptor.bDeviceProtocol);
+ break;
+ }
+
+ /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
+ switch (hubCharacteristics & HUB_CHAR_TTTT) {
+ case HUB_TTTT_8_BITS:
+ if (dev->descriptor.bDeviceProtocol != 0) {
+ hub->tt.think_time = 666;
+ debug("TT requires at most %d FS bit times (%d ns)\n",
+ 8, hub->tt.think_time);
+ }
+ break;
+ case HUB_TTTT_16_BITS:
+ hub->tt.think_time = 666 * 2;
+ debug("TT requires at most %d FS bit times (%d ns)\n",
+ 16, hub->tt.think_time);
+ break;
+ case HUB_TTTT_24_BITS:
+ hub->tt.think_time = 666 * 3;
+ debug("TT requires at most %d FS bit times (%d ns)\n",
+ 24, hub->tt.think_time);
+ break;
+ case HUB_TTTT_32_BITS:
+ hub->tt.think_time = 666 * 4;
+ debug("TT requires at most %d FS bit times (%d ns)\n",
+ 32, hub->tt.think_time);
+ break;
+ }
+
debug("power on to power good time: %dms\n",
descriptor->bPwrOn2PwrGood * 2);
debug("hub controller current requirement: %dmA\n",