diff options
| author | Bin Meng <bmeng.cn@gmail.com> | 2017-07-19 21:51:16 +0800 |
|---|---|---|
| committer | Marek Vasut <marex@denx.de> | 2017-07-28 23:34:34 +0200 |
| commit | 5624dfd5aa91c244519ec60b40b4a42b4d9a43ca (patch) | |
| tree | e7a0a302d46a576835159e30477071f7c599287b /common/usb_hub.c | |
| parent | 493b8dd070f2412b49190b71b44baddbb2b24e37 (diff) | |
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/usb_hub.c')
| -rw-r--r-- | common/usb_hub.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/common/usb_hub.c b/common/usb_hub.c index 18c366ab7e..bbb1155089 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", |