Initial support for USB hubs.

Add support for detecting, initializing, and enumerating USB hubs.

1 files changed, 138 insertions, 0 deletions

diff --git a/src/usb-hub.c b/src/usb-hub.c
new file mode 100644
index 0000000..ce9326b
--- /dev/null
+++ b/src/usb-hub.c
@@ -0,0 +1,138 @@
+// Code for handling standard USB hubs.
+//
+// Copyright (C) 2010  Kevin O'Connor <kevin@koconnor.net>
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+
+#include "util.h" // dprintf
+#include "config.h" // CONFIG_USB_HUB
+#include "usb-hub.h" // struct usb_hub_descriptor
+#include "usb.h" // struct usb_s
+
+static int
+get_hub_desc(struct usb_hub_descriptor *desc, u32 endp)
+{
+    struct usb_ctrlrequest req;
+    req.bRequestType = USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_DEVICE;
+    req.bRequest = USB_REQ_GET_DESCRIPTOR;
+    req.wValue = USB_DT_HUB<<8;
+    req.wIndex = 0;
+    req.wLength = sizeof(*desc);
+    return send_default_control(endp, &req, desc);
+}
+
+static int
+set_port_feature(int port, int feature, u32 endp)
+{
+    struct usb_ctrlrequest req;
+    req.bRequestType = USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_OTHER;
+    req.bRequest = USB_REQ_SET_FEATURE;
+    req.wValue = feature;
+    req.wIndex = port;
+    req.wLength = 0;
+    return send_default_control(endp, &req, NULL);
+}
+
+static int
+clear_port_feature(int port, int feature, u32 endp)
+{
+    struct usb_ctrlrequest req;
+    req.bRequestType = USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_OTHER;
+    req.bRequest = USB_REQ_CLEAR_FEATURE;
+    req.wValue = feature;
+    req.wIndex = port;
+    req.wLength = 0;
+    return send_default_control(endp, &req, NULL);
+}
+
+static int
+get_port_status(int port, struct usb_port_status *sts, u32 endp)
+{
+    struct usb_ctrlrequest req;
+    req.bRequestType = USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_OTHER;
+    req.bRequest = USB_REQ_GET_STATUS;
+    req.wValue = 0;
+    req.wIndex = port;
+    req.wLength = sizeof(*sts);
+    return send_default_control(endp, &req, sts);
+}
+
+// Configure a usb hub and then find devices connected to it.
+int
+usb_hub_init(u32 endp)
+{
+    if (!CONFIG_USB_HUB)
+        return 0;
+
+    struct usb_hub_descriptor desc;
+    int ret = get_hub_desc(&desc, endp);
+    if (ret)
+        return ret;
+
+    // Turn on power to all ports.
+    int i;
+    for (i=1; i<=desc.bNbrPorts; i++) {
+        ret = set_port_feature(i, USB_PORT_FEAT_POWER, endp);
+        if (ret)
+            goto fail;
+    }
+
+    // Wait for port detection.
+    msleep(desc.bPwrOn2PwrGood * 2 + USB_TIME_SIGATT);
+    // XXX - should poll for ports becoming active sooner and then
+    // possibly wait USB_TIME_ATTDB.
+
+    // Detect down stream devices.
+    struct usb_s *cntl = endp2cntl(endp);
+    int totalcount = 0;
+    for (i=1; i<=desc.bNbrPorts; i++) {
+        struct usb_port_status sts;
+        ret = get_port_status(i, &sts, endp);
+        if (ret)
+            goto fail;
+        if (!(sts.wPortStatus & USB_PORT_STAT_CONNECTION))
+            // XXX - power down port?
+            continue;
+
+        // Reset port.
+        ret = set_port_feature(i, USB_PORT_FEAT_RESET, endp);
+        if (ret)
+            goto fail;
+
+        // Wait for reset to complete.
+        u64 end = calc_future_tsc(USB_TIME_DRST * 2);
+        for (;;) {
+            ret = get_port_status(i, &sts, endp);
+            if (ret)
+                goto fail;
+            if (!(sts.wPortStatus & USB_PORT_STAT_RESET))
+                break;
+            if (check_time(end)) {
+                // Timeout.
+                warn_timeout();
+                goto fail;
+            }
+            yield();
+        }
+        if (!(sts.wPortStatus & USB_PORT_STAT_CONNECTION))
+            // Device no longer present.  XXX - power down port?
+            continue;
+
+        // XXX - should try to parallelize configuration.
+        int count = configure_usb_device(
+            cntl, !!(sts.wPortStatus & USB_PORT_STAT_LOW_SPEED));
+        if (! count) {
+            // Shutdown port
+            ret = clear_port_feature(i, USB_PORT_FEAT_ENABLE, endp);
+            if (ret)
+                goto fail;
+        }
+        totalcount += count;
+    }
+
+    return totalcount;
+
+fail:
+    dprintf(1, "Failure on hub setup\n");
+    return 0;
+}