usb.c

static void usb_hub_power_on(struct usb_hub_device *hub)
{
	int i;
	struct usb_device *dev;

	dev = hub->pusb_dev;
	/* Enable power to the ports */
	USB_HUB_PRINTF("enabling power on all ports\n");
	for (i = 0; i < dev->maxchild; i++) {
		usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
		USB_HUB_PRINTF("port %d returns %lX\n", i + 1, dev->status);
		wait_ms(hub->desc.bPwrOn2PwrGood * 2);
	}
}

void usb_hub_reset(void)
{
	usb_hub_index = 0;
}

struct usb_hub_device *usb_hub_allocate(void)
{
	if (usb_hub_index < USB_MAX_HUB)
		return &hub_dev[usb_hub_index++];

	printf("ERROR: USB_MAX_HUB (%d) reached\n", USB_MAX_HUB);
	return NULL;
}

#define MAX_TRIES 5

static int hub_port_reset(struct usb_device *dev, int port,
			unsigned short *portstat)
{
	int tries;
	struct usb_port_status portsts;
	unsigned short portstatus, portchange;

	USB_HUB_PRINTF("hub_port_reset: resetting port %d...\n", port);
	for (tries = 0; tries < MAX_TRIES; tries++) {

		usb_set_port_feature(dev, port + 1, USB_PORT_FEAT_RESET);
		wait_ms(200);

		if (usb_get_port_status(dev, port + 1, &portsts) < 0) {
			USB_HUB_PRINTF("get_port_status failed status %lX\n",
					dev->status);
			return -1;
		}
		portstatus = le16_to_cpu(portsts.wPortStatus);
		portchange = le16_to_cpu(portsts.wPortChange);
		USB_HUB_PRINTF("portstatus %x, change %x, %s\n",
				portstatus, portchange,
				portstatus&(1<<USB_PORT_FEAT_LOWSPEED) ? \
						"Low Speed" : "High Speed");
		USB_HUB_PRINTF("STAT_C_CONNECTION = %d STAT_CONNECTION = %d" \
			       "  USB_PORT_STAT_ENABLE %d\n",
			(portchange & USB_PORT_STAT_C_CONNECTION) ? 1 : 0,
			(portstatus & USB_PORT_STAT_CONNECTION) ? 1 : 0,
			(portstatus & USB_PORT_STAT_ENABLE) ? 1 : 0);

		if ((portchange & USB_PORT_STAT_C_CONNECTION) ||
		    !(portstatus & USB_PORT_STAT_CONNECTION))
			return -1;

		if (portstatus & USB_PORT_STAT_ENABLE)
			break;

		wait_ms(200);
	}

	if (tries == MAX_TRIES) {
		USB_HUB_PRINTF("Cannot enable port %i after %i retries, " \
				"disabling port.\n", port + 1, MAX_TRIES);
		USB_HUB_PRINTF("Maybe the USB cable is bad?\n");
		return -1;
	}

	usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_C_RESET);
	*portstat = portstatus;
	return 0;
}


void usb_hub_port_connect_change(struct usb_device *dev, int port)
{
	struct usb_device *usb;
	struct usb_port_status portsts;
	unsigned short portstatus, portchange;

	/* Check status */
	if (usb_get_port_status(dev, port + 1, &portsts) < 0) {
		USB_HUB_PRINTF("get_port_status failed\n");
		return;
	}

	portstatus = le16_to_cpu(portsts.wPortStatus);
	portchange = le16_to_cpu(portsts.wPortChange);
	USB_HUB_PRINTF("portstatus %x, change %x, %s\n",
			portstatus, portchange,
			portstatus&(1 << USB_PORT_FEAT_LOWSPEED) ? \
						"Low Speed" : "High Speed");

	/* Clear the connection change status */
	usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_C_CONNECTION);

	/* Disconnect any existing devices under this port */
	if (((!(portstatus & USB_PORT_STAT_CONNECTION)) &&
	     (!(portstatus & USB_PORT_STAT_ENABLE))) || (dev->children[port])) {
		USB_HUB_PRINTF("usb_disconnect(&hub->children[port]);\n");
		/* Return now if nothing is connected */
		if (!(portstatus & USB_PORT_STAT_CONNECTION))
			return;
	}
	wait_ms(200);

	/* Reset the port */
	if (hub_port_reset(dev, port, &portstatus) < 0) {
		printf("cannot reset port %i!?\n", port + 1);
		return;
	}

	wait_ms(200);

	/* Allocate a new device struct for it */
	usb = usb_alloc_new_device();
	usb->slow = (portstatus & USB_PORT_STAT_LOW_SPEED) ? 1 : 0;

	dev->children[port] = usb;
	usb->parent = dev;
	/* Run it through the hoops (find a driver, etc) */
	if (usb_new_device(usb)) {
		/* Woops, disable the port */
		USB_HUB_PRINTF("hub: disabling port %d\n", port + 1);
		usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_ENABLE);
	}
}


int usb_hub_configure(struct usb_device *dev)
{
	unsigned char buffer[USB_BUFSIZ], *bitmap;
	struct usb_hub_descriptor *descriptor;
	struct usb_hub_status *hubsts;
	int i;
	struct usb_hub_device *hub;

	/* "allocate" Hub device */
	hub = usb_hub_allocate();
	if (hub == NULL)
		return -1;
	hub->pusb_dev = dev;
	/* Get the the hub descriptor */
	if (usb_get_hub_descriptor(dev, buffer, 4) < 0) {
		USB_HUB_PRINTF("usb_hub_configure: failed to get hub " \
				   "descriptor, giving up %lX\n", dev->status);
		return -1;
	}
	descriptor = (struct usb_hub_descriptor *)buffer;

	/* silence compiler warning if USB_BUFSIZ is > 256 [= sizeof(char)] */
	i = descriptor->bLength;
	if (i > USB_BUFSIZ) {
		USB_HUB_PRINTF("usb_hub_configure: failed to get hub " \
				"descriptor - too long: %d\n",
				descriptor->bLength);
		return -1;
	}

	if (usb_get_hub_descriptor(dev, buffer, descriptor->bLength) < 0) {
		USB_HUB_PRINTF("usb_hub_configure: failed to get hub " \
				"descriptor 2nd giving up %lX\n", dev->status);
		return -1;
	}
	memcpy((unsigned char *)&hub->desc, buffer, descriptor->bLength);
	/* adjust 16bit values */
	hub->desc.wHubCharacteristics =
				le16_to_cpu(descriptor->wHubCharacteristics);
	/* set the bitmap */
	bitmap = (unsigned char *)&hub->desc.DeviceRemovable[0];
	/* devices not removable by default */
	memset(bitmap, 0xff, (USB_MAXCHILDREN+1+7)/8);
	bitmap = (unsigned char *)&hub->desc.PortPowerCtrlMask[0];
	memset(bitmap, 0xff, (USB_MAXCHILDREN+1+7)/8); /* PowerMask = 1B */

	for (i = 0; i < ((hub->desc.bNbrPorts + 1 + 7)/8); i++)
		hub->desc.DeviceRemovable[i] = descriptor->DeviceRemovable[i];

	for (i = 0; i < ((hub->desc.bNbrPorts + 1 + 7)/8); i++)
		hub->desc.DeviceRemovable[i] = descriptor->PortPowerCtrlMask[i];

	dev->maxchild = descriptor->bNbrPorts;
	USB_HUB_PRINTF("%d ports detected\n", dev->maxchild);

	switch (hub->desc.wHubCharacteristics & HUB_CHAR_LPSM) {
	case 0x00:
		USB_HUB_PRINTF("ganged power switching\n");
		break;
	case 0x01:
		USB_HUB_PRINTF("individual port power switching\n");
		break;
	case 0x02:
	case 0x03:
		USB_HUB_PRINTF("unknown reserved power switching mode\n");
		break;
	}

	if (hub->desc.wHubCharacteristics & HUB_CHAR_COMPOUND)
		USB_HUB_PRINTF("part of a compound device\n");
	else
		USB_HUB_PRINTF("standalone hub\n");

	switch (hub->desc.wHubCharacteristics & HUB_CHAR_OCPM) {
	case 0x00:
		USB_HUB_PRINTF("global over-current protection\n");
		break;
	case 0x08:
		USB_HUB_PRINTF("individual port over-current protection\n");
		break;
	case 0x10:
	case 0x18:
		USB_HUB_PRINTF("no over-current protection\n");
		break;
	}

	USB_HUB_PRINTF("power on to power good time: %dms\n",
			descriptor->bPwrOn2PwrGood * 2);
	USB_HUB_PRINTF("hub controller current requirement: %dmA\n",
			descriptor->bHubContrCurrent);

	for (i = 0; i < dev->maxchild; i++)
		USB_HUB_PRINTF("port %d is%s removable\n", i + 1,
			hub->desc.DeviceRemovable[(i + 1) / 8] & \
					   (1 << ((i + 1) % 8)) ? " not" : "");

	if (sizeof(struct usb_hub_status) > USB_BUFSIZ) {
		USB_HUB_PRINTF("usb_hub_configure: failed to get Status - " \
				"too long: %d\n", descriptor->bLength);
		return -1;
	}

	if (usb_get_hub_status(dev, buffer) < 0) {
		USB_HUB_PRINTF("usb_hub_configure: failed to get Status %lX\n",
				dev->status);
		return -1;
	}

	hubsts = (struct usb_hub_status *)buffer;
	USB_HUB_PRINTF("get_hub_status returned status %X, change %X\n",
			le16_to_cpu(hubsts->wHubStatus),
			le16_to_cpu(hubsts->wHubChange));
	USB_HUB_PRINTF("local power source is %s\n",
		(le16_to_cpu(hubsts->wHubStatus) & HUB_STATUS_LOCAL_POWER) ? \
		"lost (inactive)" : "good");
	USB_HUB_PRINTF("%sover-current condition exists\n",
		(le16_to_cpu(hubsts->wHubStatus) & HUB_STATUS_OVERCURRENT) ? \
		"" : "no ");
	usb_hub_power_on(hub);

	for (i = 0; i < dev->maxchild; i++) {
		struct usb_port_status portsts;
		unsigned short portstatus, portchange;

		if (usb_get_port_status(dev, i + 1, &portsts) < 0) {
			USB_HUB_PRINTF("get_port_status failed\n");
			continue;
		}

		portstatus = le16_to_cpu(portsts.wPortStatus);
		portchange = le16_to_cpu(portsts.wPortChange);
		USB_HUB_PRINTF("Port %d Status %X Change %X\n",
				i + 1, portstatus, portchange);

		if (portchange & USB_PORT_STAT_C_CONNECTION) {
			USB_HUB_PRINTF("port %d connection change\n", i + 1);
			usb_hub_port_connect_change(dev, i);
		}
		if (portchange & USB_PORT_STAT_C_ENABLE) {
			USB_HUB_PRINTF("port %d enable change, status %x\n",
					i + 1, portstatus);
			usb_clear_port_feature(dev, i + 1,
						USB_PORT_FEAT_C_ENABLE);

			/* EM interference sometimes causes bad shielded USB
			 * devices to be shutdown by the hub, this hack enables
			 * them again. Works at least with mouse driver */
			if (!(portstatus & USB_PORT_STAT_ENABLE) &&
			     (portstatus & USB_PORT_STAT_CONNECTION) &&
			     ((dev->children[i]))) {
				USB_HUB_PRINTF("already running port %i "  \
						"disabled by hub (EMI?), " \
						"re-enabling...\n", i + 1);
					usb_hub_port_connect_change(dev, i);
			}
		}
		if (portstatus & USB_PORT_STAT_SUSPEND) {
			USB_HUB_PRINTF("port %d suspend change\n", i + 1);
			usb_clear_port_feature(dev, i + 1,
						USB_PORT_FEAT_SUSPEND);
		}

		if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
			USB_HUB_PRINTF("port %d over-current change\n", i + 1);
			usb_clear_port_feature(dev, i + 1,
						USB_PORT_FEAT_C_OVER_CURRENT);
			usb_hub_power_on(hub);
		}

		if (portchange & USB_PORT_STAT_C_RESET) {
			USB_HUB_PRINTF("port %d reset change\n", i + 1);
			usb_clear_port_feature(dev, i + 1,
						USB_PORT_FEAT_C_RESET);
		}
	} /* end for i all ports */

	return 0;
}

int usb_hub_probe(struct usb_device *dev, int ifnum)
{
	struct usb_interface_descriptor *iface;
	struct usb_endpoint_descriptor *ep;
	int ret;

	iface = &dev->config.if_desc[ifnum];
	/* Is it a hub? */
	if (iface->bInterfaceClass != USB_CLASS_HUB)
		return 0;
	/* Some hubs have a subclass of 1, which AFAICT according to the */
	/*  specs is not defined, but it works */
	if ((iface->bInterfaceSubClass != 0) &&
	    (iface->bInterfaceSubClass != 1))
		return 0;
	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
	if (iface->bNumEndpoints != 1)
		return 0;
	ep = &iface->ep_desc[0];
	/* Output endpoint? Curiousier and curiousier.. */
	if (!(ep->bEndpointAddress & USB_DIR_IN))
		return 0;
	/* If it's not an interrupt endpoint, we'd better punt! */
	if ((ep->bmAttributes & 3) != 3)
		return 0;
	/* We found a hub */
	USB_HUB_PRINTF("USB hub found\n");
	ret = usb_hub_configure(dev);
	return ret;
}

/* EOF */