path: root/drivers/usb/usbip/vhci_hcd.c

/*
 * Copyright (C) 2003-2008 Takahiro Hirofuchi
 * Copyright (C) 2015-2016 Nobuo Iwata
 *
 * This is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
 * USA.
 */

#include <linux/init.h>
#include <linux/file.h>
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

#include "usbip_common.h"
#include "vhci.h"

#define DRIVER_AUTHOR "Takahiro Hirofuchi"
#define DRIVER_DESC "USB/IP 'Virtual' Host Controller (VHCI) Driver"

/*
 * TODO
 *	- update root hub emulation
 *	- move the emulation code to userland ?
 *		porting to other operating systems
 *		minimize kernel code
 *	- add suspend/resume code
 *	- clean up everything
 */

/* See usb gadget dummy hcd */

static int vhci_hub_status(struct usb_hcd *hcd, char *buff);
static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
			    u16 wIndex, char *buff, u16 wLength);
static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
			    gfp_t mem_flags);
static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status);
static int vhci_start(struct usb_hcd *vhci_hcd);
static void vhci_stop(struct usb_hcd *hcd);
static int vhci_get_frame_number(struct usb_hcd *hcd);

static const char driver_name[] = "vhci_hcd";
static const char driver_desc[] = "USB/IP Virtual Host Controller";

int vhci_num_controllers = VHCI_NR_HCS;
struct vhci *vhcis;

static const char * const bit_desc[] = {
	"CONNECTION",		/*0*/
	"ENABLE",		/*1*/
	"SUSPEND",		/*2*/
	"OVER_CURRENT",		/*3*/
	"RESET",		/*4*/
	"L1",			/*5*/
	"R6",			/*6*/
	"R7",			/*7*/
	"POWER",		/*8*/
	"LOWSPEED",		/*9*/
	"HIGHSPEED",		/*10*/
	"PORT_TEST",		/*11*/
	"INDICATOR",		/*12*/
	"R13",			/*13*/
	"R14",			/*14*/
	"R15",			/*15*/
	"C_CONNECTION",		/*16*/
	"C_ENABLE",		/*17*/
	"C_SUSPEND",		/*18*/
	"C_OVER_CURRENT",	/*19*/
	"C_RESET",		/*20*/
	"C_L1",			/*21*/
	"R22",			/*22*/
	"R23",			/*23*/
	"R24",			/*24*/
	"R25",			/*25*/
	"R26",			/*26*/
	"R27",			/*27*/
	"R28",			/*28*/
	"R29",			/*29*/
	"R30",			/*30*/
	"R31",			/*31*/
};

static const char * const bit_desc_ss[] = {
	"CONNECTION",		/*0*/
	"ENABLE",		/*1*/
	"SUSPEND",		/*2*/
	"OVER_CURRENT",		/*3*/
	"RESET",		/*4*/
	"L1",			/*5*/
	"R6",			/*6*/
	"R7",			/*7*/
	"R8",			/*8*/
	"POWER",		/*9*/
	"HIGHSPEED",		/*10*/
	"PORT_TEST",		/*11*/
	"INDICATOR",		/*12*/
	"R13",			/*13*/
	"R14",			/*14*/
	"R15",			/*15*/
	"C_CONNECTION",		/*16*/
	"C_ENABLE",		/*17*/
	"C_SUSPEND",		/*18*/
	"C_OVER_CURRENT",	/*19*/
	"C_RESET",		/*20*/
	"C_BH_RESET",		/*21*/
	"C_LINK_STATE",		/*22*/
	"C_CONFIG_ERROR",	/*23*/
	"R24",			/*24*/
	"R25",			/*25*/
	"R26",			/*26*/
	"R27",			/*27*/
	"R28",			/*28*/
	"R29",			/*29*/
	"R30",			/*30*/
	"R31",			/*31*/
};

static void dump_port_status_diff(u32 prev_status, u32 new_status, bool usb3)
{
	int i = 0;
	u32 bit = 1;
	const char * const *desc = bit_desc;

	if (usb3)
		desc = bit_desc_ss;

	pr_debug("status prev -> new: %08x -> %08x\n", prev_status, new_status);
	while (bit) {
		u32 prev = prev_status & bit;
		u32 new = new_status & bit;
		char change;

		if (!prev && new)
			change = '+';
		else if (prev && !new)
			change = '-';
		else
			change = ' ';

		if (prev || new) {
			pr_debug(" %c%s\n", change, desc[i]);

			if (bit == 1) /* USB_PORT_STAT_CONNECTION */
				pr_debug(" %c%s\n", change, "USB_PORT_STAT_SPEED_5GBPS");
		}
		bit <<= 1;
		i++;
	}
	pr_debug("\n");
}

void rh_port_connect(struct vhci_device *vdev, enum usb_device_speed speed)
{
	struct vhci_hcd	*vhci_hcd = vdev_to_vhci_hcd(vdev);
	struct vhci *vhci = vhci_hcd->vhci;
	int		rhport = vdev->rhport;
	u32		status;
	unsigned long	flags;

	usbip_dbg_vhci_rh("rh_port_connect %d\n", rhport);

	spin_lock_irqsave(&vhci->lock, flags);

	status = vhci_hcd->port_status[rhport];

	status |= USB_PORT_STAT_CONNECTION | (1 << USB_PORT_FEAT_C_CONNECTION);

	switch (speed) {
	case USB_SPEED_HIGH:
		status |= USB_PORT_STAT_HIGH_SPEED;
		break;
	case USB_SPEED_LOW:
		status |= USB_PORT_STAT_LOW_SPEED;
		break;
	default:
		break;
	}

	vhci_hcd->port_status[rhport] = status;

	spin_unlock_irqrestore(&vhci->lock, flags);

	usb_hcd_poll_rh_status(vhci_hcd_to_hcd(vhci_hcd));
}

static void rh_port_disconnect(struct vhci_device *vdev)
{
	struct vhci_hcd	*vhci_hcd = vdev_to_vhci_hcd(vdev);
	struct vhci *vhci = vhci_hcd->vhci;
	int		rhport = vdev->rhport;
	u32		status;
	unsigned long	flags;

	usbip_dbg_vhci_rh("rh_port_disconnect %d\n", rhport);

	spin_lock_irqsave(&vhci->lock, flags);

	status = vhci_hcd->port_status[rhport];

	status &= ~USB_PORT_STAT_CONNECTION;
	status |= (1 << USB_PORT_FEAT_C_CONNECTION);

	vhci_hcd->port_status[rhport] = status;

	spin_unlock_irqrestore(&vhci->lock, flags);
	usb_hcd_poll_rh_status(vhci_hcd_to_hcd(vhci_hcd));
}

#define PORT_C_MASK				\
	((USB_PORT_STAT_C_CONNECTION		\
	  | USB_PORT_STAT_C_ENABLE		\
	  | USB_PORT_STAT_C_SUSPEND		\
	  | USB_PORT_STAT_C_OVERCUR