drivers/usb/host/ehci-sysfs.c

/*
 * Copyright (C) 2007 by Alan Stern
 *
 * This program 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 program 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/* this file is part of ehci-hcd.c */


/* Display the ports dedicated to the companion controller */
static ssize_t show_companion(struct device *dev,
			      struct device_attribute *attr,
			      char *buf)
{
	struct ehci_hcd		*ehci;
	int			nports, index, n;
	int			count = PAGE_SIZE;
	char			*ptr = buf;

	ehci = hcd_to_ehci(bus_to_hcd(dev_get_drvdata(dev)));
	nports = HCS_N_PORTS(ehci->hcs_params);

	for (index = 0; index < nports; ++index) {
		if (test_bit(index, &ehci->companion_ports)) {
			n = scnprintf(ptr, count, "%d\n", index + 1);
			ptr += n;
			count -= n;
		}
	}
	return ptr - buf;
}

/*
 * Dedicate or undedicate a port to the companion controller.
 * Syntax is "[-]portnum", where a leading '-' sign means
 * return control of the port to the EHCI controller.
 */
static ssize_t store_companion(struct device *dev,
			       struct device_attribute *attr,
			       const char *buf, size_t count)
{
	struct ehci_hcd		*ehci;
	int			portnum, new_owner;

	ehci = hcd_to_ehci(bus_to_hcd(dev_get_drvdata(dev)));
	new_owner = PORT_OWNER;		/* Owned by companion */
	if (sscanf(buf, "%d", &portnum) != 1)
		return -EINVAL;
	if (portnum < 0) {
		portnum = - portnum;
		new_owner = 0;		/* Owned by EHCI */
	}
	if (portnum <= 0 || portnum > HCS_N_PORTS(ehci->hcs_params))
		return -ENOENT;
	portnum--;
	if (new_owner)
		set_bit(portnum, &ehci->companion_ports);
	else
		clear_bit(portnum, &ehci->companion_ports);
	set_owner(ehci, portnum, new_owner);
	return count;
}
static DEVICE_ATTR(companion, 0644, show_companion, store_companion);

static inline int create_sysfs_files(struct ehci_hcd *ehci)
{
	int	i = 0;

	/* with integrated TT there is no companion! */
	if (!ehci_is_TDI(ehci))
		i = device_create_file(ehci_to_hcd(ehci)->self.controller,
				       &dev_attr_companion);
	return i;
}

static inline void remove_sysfs_files(struct ehci_hcd *ehci)
{
	/* with integrated TT there is no companion! */
	if (!ehci_is_TDI(ehci))
		device_remove_file(ehci_to_hcd(ehci)->self.controller,
				   &dev_attr_companion);
}