src/usb-hub.c

   1 // Code for handling standard USB hubs.
   2 //
   3 // Copyright (C) 2010  Kevin O'Connor <kevin@koconnor.net>
   4 //
   5 // This file may be distributed under the terms of the GNU LGPLv3 license.
   6
   7 #include "util.h" // dprintf
   8 #include "config.h" // CONFIG_USB_HUB
   9 #include "usb-hub.h" // struct usb_hub_descriptor
  10 #include "usb.h" // struct usb_s
  11
  12 static int
  13 get_hub_desc(struct usb_hub_descriptor *desc, u32 endp)
  14 {
  15     struct usb_ctrlrequest req;
  16     req.bRequestType = USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_DEVICE;
  17     req.bRequest = USB_REQ_GET_DESCRIPTOR;
  18     req.wValue = USB_DT_HUB<<8;
  19     req.wIndex = 0;
  20     req.wLength = sizeof(*desc);
  21     return send_default_control(endp, &req, desc);
  22 }
  23
  24 static int
  25 set_port_feature(int port, int feature, u32 endp)
  26 {
  27     struct usb_ctrlrequest req;
  28     req.bRequestType = USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_OTHER;
  29     req.bRequest = USB_REQ_SET_FEATURE;
  30     req.wValue = feature;
  31     req.wIndex = port;
  32     req.wLength = 0;
  33     return send_default_control(endp, &req, NULL);
  34 }
  35
  36 static int
  37 clear_port_feature(int port, int feature, u32 endp)
  38 {
  39     struct usb_ctrlrequest req;
  40     req.bRequestType = USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_OTHER;
  41     req.bRequest = USB_REQ_CLEAR_FEATURE;
  42     req.wValue = feature;
  43     req.wIndex = port;
  44     req.wLength = 0;
  45     return send_default_control(endp, &req, NULL);
  46 }
  47
  48 static int
  49 get_port_status(int port, struct usb_port_status *sts, u32 endp)
  50 {
  51     struct usb_ctrlrequest req;
  52     req.bRequestType = USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_OTHER;
  53     req.bRequest = USB_REQ_GET_STATUS;
  54     req.wValue = 0;
  55     req.wIndex = port;
  56     req.wLength = sizeof(*sts);
  57     return send_default_control(endp, &req, sts);
  58 }
  59
  60 // Configure a usb hub and then find devices connected to it.
  61 int
  62 usb_hub_init(u32 endp)
  63 {
  64     if (!CONFIG_USB_HUB)
  65         return 0;
  66
  67     struct usb_hub_descriptor desc;
  68     int ret = get_hub_desc(&desc, endp);
  69     if (ret)
  70         return ret;
  71
  72     // Turn on power to all ports.
  73     int i;
  74     for (i=1; i<=desc.bNbrPorts; i++) {
  75         ret = set_port_feature(i, USB_PORT_FEAT_POWER, endp);
  76         if (ret)
  77             goto fail;
  78     }
  79
  80     // Wait for port detection.
  81     msleep(desc.bPwrOn2PwrGood * 2 + USB_TIME_SIGATT);
  82     // XXX - should poll for ports becoming active sooner and then
  83     // possibly wait USB_TIME_ATTDB.
  84
  85     // Detect down stream devices.
  86     struct usb_s *cntl = endp2cntl(endp);
  87     int totalcount = 0;
  88     for (i=1; i<=desc.bNbrPorts; i++) {
  89         struct usb_port_status sts;
  90         ret = get_port_status(i, &sts, endp);
  91         if (ret)
  92             goto fail;
  93         if (!(sts.wPortStatus & USB_PORT_STAT_CONNECTION))
  94             // XXX - power down port?
  95             continue;
  96
  97         // Reset port.
  98         ret = set_port_feature(i, USB_PORT_FEAT_RESET, endp);
  99         if (ret)
 100             goto fail;
 101
 102         // Wait for reset to complete.
 103         u64 end = calc_future_tsc(USB_TIME_DRST * 2);
 104         for (;;) {
 105             ret = get_port_status(i, &sts, endp);
 106             if (ret)
 107                 goto fail;
 108             if (!(sts.wPortStatus & USB_PORT_STAT_RESET))
 109                 break;
 110             if (check_time(end)) {
 111                 // Timeout.
 112                 warn_timeout();
 113                 goto fail;
 114             }
 115             yield();
 116         }
 117         if (!(sts.wPortStatus & USB_PORT_STAT_CONNECTION))
 118             // Device no longer present.  XXX - power down port?
 119             continue;
 120
 121         // XXX - should try to parallelize configuration.
 122         int count = configure_usb_device(
 123             cntl, !!(sts.wPortStatus & USB_PORT_STAT_LOW_SPEED));
 124         if (! count) {
 125             // Shutdown port
 126             ret = clear_port_feature(i, USB_PORT_FEAT_ENABLE, endp);
 127             if (ret)
 128                 goto fail;
 129         }
 130         totalcount += count;
 131     }
 132
 133     return totalcount;
 134
 135 fail:
 136     dprintf(1, "Failure on hub setup\n");
 137     return 0;
 138 }