LXR linux/drivers/usb/host/ehci-sysfs.c

   1/*
   2 * Copyright (C) 2007 by Alan Stern
   3 *
   4 * This program is free software; you can redistribute it and/or modify it
   5 * under the terms of the GNU General Public License as published by the
   6 * Free Software Foundation; either version 2 of the License, or (at your
   7 * option) any later version.
   8 *
   9 * This program is distributed in the hope that it will be useful, but
  10 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  11 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12 * for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write to the Free Software Foundation,
  16 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17 */
  18
  19/* this file is part of ehci-hcd.c */
  20
  21
  22/* Display the ports dedicated to the companion controller */
  23static ssize_t show_companion(struct device *dev,
  24                              struct device_attribute *attr,
  25                              char *buf)
  26{
  27        struct ehci_hcd         *ehci;
  28        int                     nports, index, n;
  29        int                     count = PAGE_SIZE;
  30        char                    *ptr = buf;
  31
  32        ehci = hcd_to_ehci(dev_get_drvdata(dev));
  33        nports = HCS_N_PORTS(ehci->hcs_params);
  34
  35        for (index = 0; index < nports; ++index) {
  36                if (test_bit(index, &ehci->companion_ports)) {
  37                        n = scnprintf(ptr, count, "%d\n", index + 1);
  38                        ptr += n;
  39                        count -= n;
  40                }
  41        }
  42        return ptr - buf;
  43}
  44
  45/*
  46 * Dedicate or undedicate a port to the companion controller.
  47 * Syntax is "[-]portnum", where a leading '-' sign means
  48 * return control of the port to the EHCI controller.
  49 */
  50static ssize_t store_companion(struct device *dev,
  51                               struct device_attribute *attr,
  52                               const char *buf, size_t count)
  53{
  54        struct ehci_hcd         *ehci;
  55        int                     portnum, new_owner;
  56
  57        ehci = hcd_to_ehci(dev_get_drvdata(dev));
  58        new_owner = PORT_OWNER;         /* Owned by companion */
  59        if (sscanf(buf, "%d", &portnum) != 1)
  60                return -EINVAL;
  61        if (portnum < 0) {
  62                portnum = - portnum;
  63                new_owner = 0;          /* Owned by EHCI */
  64        }
  65        if (portnum <= 0 || portnum > HCS_N_PORTS(ehci->hcs_params))
  66                return -ENOENT;
  67        portnum--;
  68        if (new_owner)
  69                set_bit(portnum, &ehci->companion_ports);
  70        else
  71                clear_bit(portnum, &ehci->companion_ports);
  72        set_owner(ehci, portnum, new_owner);
  73        return count;
  74}
  75static DEVICE_ATTR(companion, 0644, show_companion, store_companion);
  76
  77
  78/*
  79 * Display / Set uframe_periodic_max
  80 */
  81static ssize_t show_uframe_periodic_max(struct device *dev,
  82                                        struct device_attribute *attr,
  83                                        char *buf)
  84{
  85        struct ehci_hcd         *ehci;
  86        int                     n;
  87
  88        ehci = hcd_to_ehci(dev_get_drvdata(dev));
  89        n = scnprintf(buf, PAGE_SIZE, "%d\n", ehci->uframe_periodic_max);
  90        return n;
  91}
  92
  93
  94static ssize_t store_uframe_periodic_max(struct device *dev,
  95                                        struct device_attribute *attr,
  96                                        const char *buf, size_t count)
  97{
  98        struct ehci_hcd         *ehci;
  99        unsigned                uframe_periodic_max;
 100        unsigned                uframe;
 101        unsigned long           flags;
 102        ssize_t                 ret;
 103
 104        ehci = hcd_to_ehci(dev_get_drvdata(dev));
 105        if (kstrtouint(buf, 0, &uframe_periodic_max) < 0)
 106                return -EINVAL;
 107
 108        if (uframe_periodic_max < 100 || uframe_periodic_max >= 125) {
 109                ehci_info(ehci, "rejecting invalid request for "
 110                                "uframe_periodic_max=%u\n", uframe_periodic_max);
 111                return -EINVAL;
 112        }
 113
 114        ret = -EINVAL;
 115
 116        /*
 117         * lock, so that our checking does not race with possible periodic
 118         * bandwidth allocation through submitting new urbs.
 119         */
 120        spin_lock_irqsave (&ehci->lock, flags);
 121
 122        /*
 123         * for request to decrease max periodic bandwidth, we have to check
 124         * to see whether the decrease is possible.
 125         */
 126        if (uframe_periodic_max < ehci->uframe_periodic_max) {
 127                u8              allocated_max = 0;
 128
 129                for (uframe = 0; uframe < EHCI_BANDWIDTH_SIZE; ++uframe)
 130                        allocated_max = max(allocated_max,
 131                                        ehci->bandwidth[uframe]);
 132
 133                if (allocated_max > uframe_periodic_max) {
 134                        ehci_info(ehci,
 135                                "cannot decrease uframe_periodic_max because "
 136                                "periodic bandwidth is already allocated "
 137                                "(%u > %u)\n",
 138                                allocated_max, uframe_periodic_max);
 139                        goto out_unlock;
 140                }
 141        }
 142
 143        /* increasing is always ok */
 144
 145        ehci_info(ehci, "setting max periodic bandwidth to %u%% "
 146                        "(== %u usec/uframe)\n",
 147                        100*uframe_periodic_max/125, uframe_periodic_max);
 148
 149        if (uframe_periodic_max != 100)
 150                ehci_warn(ehci, "max periodic bandwidth set is non-standard\n");
 151
 152        ehci->uframe_periodic_max = uframe_periodic_max;
 153        ret = count;
 154
 155out_unlock:
 156        spin_unlock_irqrestore (&ehci->lock, flags);
 157        return ret;
 158}
 159static DEVICE_ATTR(uframe_periodic_max, 0644, show_uframe_periodic_max, store_uframe_periodic_max);
 160
 161
 162static inline int create_sysfs_files(struct ehci_hcd *ehci)
 163{
 164        struct device   *controller = ehci_to_hcd(ehci)->self.controller;
 165        int     i = 0;
 166
 167        /* with integrated TT there is no companion! */
 168        if (!ehci_is_TDI(ehci))
 169                i = device_create_file(controller, &dev_attr_companion);
 170        if (i)
 171                goto out;
 172
 173        i = device_create_file(controller, &dev_attr_uframe_periodic_max);
 174out:
 175        return i;
 176}
 177
 178static inline void remove_sysfs_files(struct ehci_hcd *ehci)
 179{
 180        struct device   *controller = ehci_to_hcd(ehci)->self.controller;
 181
 182        /* with integrated TT there is no companion! */
 183        if (!ehci_is_TDI(ehci))
 184                device_remove_file(controller, &dev_attr_companion);
 185
 186        device_remove_file(controller, &dev_attr_uframe_periodic_max);
 187}
 188