text: /*
   * This file is part of the libpayload project.
   *
   * Copyright (C) 2008-2010 coresystems GmbH
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. The name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   */
  
  //#define USB_DEBUG
  
  #include <libpayload.h>
  #include "uhci.h"
  #include "uhci_private.h"
  
  typedef struct {
  	int port[2];
  } rh_inst_t;
  
  #define RH_INST(dev) ((rh_inst_t*)(dev)->data)
  
  static void
  uhci_rh_enable_port (usbdev_t *dev, int port)
  {
  	u16 value;
  	hci_t *controller = dev->controller;
  	if (port == 1)
  		port = PORTSC1;
  	else if (port == 2)
  		port = PORTSC2;
  	else {
  		usb_debug("Invalid port %d\n", port);
  		return;
  	}
  
  	uhci_reg_write16(controller, port,
  			 uhci_reg_read16(controller, port) & ~(1 << 12));	/* wakeup */
  
  	uhci_reg_write16(controller, port,
  			 uhci_reg_read16(controller, port) | 1 << 9);	/* reset */
  	mdelay (30);		// >10ms
  	uhci_reg_write16(controller, port,
  			 uhci_reg_read16(controller, port) & ~(1 << 9));
  	mdelay (1);		// >5.3us per spec, <3ms because some devices make trouble
  
  	uhci_reg_write16(controller, port,
  			 uhci_reg_read16(controller, port) | 1 << 2);	/* enable */
  	/* wait for controller to enable port */
  	/* TOTEST: how long to wait? 100ms for now */
  	int timeout = 200; /* time out after 200 * 500us == 100ms */
  	do {
  		value = uhci_reg_read16 (controller, port);
  		udelay(500); timeout--;
  	} while (((value & (1 << 2)) == 0) && (value & 0x01) && timeout);
  	if (!timeout)
  		usb_debug("Warning: uhci_rh: port enabling timed out.\n");
  }
  
  /* disable root hub */
  static void
  uhci_rh_disable_port (usbdev_t *dev, int port)
  {
  	hci_t *controller = dev->controller;
  	if (port == 1)
  		port = PORTSC1;
  	else if (port == 2)
  		port = PORTSC2;
  	else {
  		usb_debug("Invalid port %d\n", port);
  		return;
  	}
  	uhci_reg_write16(controller, port,
  			 uhci_reg_read16(controller, port) & ~4);
  	u16 value;
  	/* wait for controller to disable port */
  	/* TOTEST: how long to wait? 100ms for now */
  	int timeout = 200; /* time out after 200 * 500us == 100ms */
  	do {
  		value = uhci_reg_read16 (controller, port);
  		udelay(500); timeout--;
  	} while (((value & (1 << 2)) != 0) && timeout);
  	if (!timeout)
  		usb_debug("Warning: uhci_rh: port disabling timed out.\n");
  }
  
  static void
  uhci_rh_scanport (usbdev_t *dev, int port)
  {
  	int portsc, offset;
  	if (port == 1) {
  		portsc = PORTSC1;
  		offset = 0;
  	} else if (port == 2) {
  		portsc = PORTSC2;
  		offset = 1;
  	} else {
  		usb_debug("Invalid port %d\n", port);
  		return;
  	}
  	int devno = RH_INST (dev)->port[offset];
  	if ((dev->controller->devices[devno] != 0) && (devno != -1)) {
  		usb_detach_device(dev->controller, devno);
  		RH_INST (dev)->port[offset] = -1;
  	}
  	uhci_reg_write16(dev->controller, portsc,
  			 uhci_reg_read16(dev->controller, portsc) | (1 << 3) | (1 << 2));	// clear port state change, enable port
  
  	mdelay(100); // wait for signal to stabilize
  
  	if ((uhci_reg_read16 (dev->controller, portsc) & 1) != 0) {
  		// device attached
  
  		uhci_rh_disable_port (dev, port);
  		uhci_rh_enable_port (dev, port);
  
  		int speed = ((uhci_reg_read16 (dev->controller, portsc) >> 8) & 1);
  
  		RH_INST (dev)->port[offset] = usb_attach_device(dev->controller, dev->address, portsc, speed);
  	}
  }
  
  static int
  uhci_rh_report_port_changes (usbdev_t *dev)
  {
  	u16 stored, real;
  
  	stored = (RH_INST (dev)->port[0] == -1);
  	real = ((uhci_reg_read16 (dev->controller, PORTSC1) & 1) == 0);
  	if (stored != real) {
  		usb_debug("change on port 1\n");
  		return 1;
  	}
  
  	stored = (RH_INST (dev)->port[1] == -1);
  	real = ((uhci_reg_read16 (dev->controller, PORTSC2) & 1) == 0);
  	if (stored != real) {
  		usb_debug("change on port 2\n");
  		return 2;
  	}
  
  	// maybe detach+attach happened between two scans?
  
  	if ((uhci_reg_read16 (dev->controller, PORTSC1) & 2) > 0) {
  		usb_debug("possibly re-attached on port 1\n");
  		return 1;
  	}
  	if ((uhci_reg_read16 (dev->controller, PORTSC2) & 2) > 0) {
  		usb_debug("possibly re-attached on port 2\n");
  		return 2;
  	}
  
  	// no change
  	return -1;
  }
  
  static void
  uhci_rh_destroy (usbdev_t *dev)
  {
  	uhci_rh_disable_port (dev, 1);
  	uhci_rh_disable_port (dev, 2);
  	free (RH_INST (dev));
  }
  
  static void
  uhci_rh_poll (usbdev_t *dev)
  {
  	int port;
  	while ((port = uhci_rh_report_port_changes (dev)) != -1)
  		uhci_rh_scanport (dev, port);
  }
  
  void
  uhci_rh_init (usbdev_t *dev)
  {
  	dev->destroy = uhci_rh_destroy;
  	dev->poll = uhci_rh_poll;
  
  	uhci_rh_enable_port (dev, 1);
  	uhci_rh_enable_port (dev, 2);
  	dev->data = malloc (sizeof (rh_inst_t));
  	if (!dev->data)
  		fatal("Not enough memory for UHCI RH.\n");
  
  	RH_INST (dev)->port[0] = -1;
  	RH_INST (dev)->port[1] = -1;
  
  	/* we can set them here because a root hub _really_ shouldn't
  	   appear elsewhere */
  	dev->address = 0;
  	dev->hub = -1;
  	dev->port = -1;
  }
  