drivers/usb/core/port.c

   1 /*
   2  * usb port device code
   3  *
   4  * Copyright (C) 2012 Intel Corp
   5  *
   6  * Author: Lan Tianyu <tianyu.lan@intel.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15  * for more details.
  16  *
  17  */
  18
  19 #include <linux/slab.h>
  20 #include <linux/pm_qos.h>
  21
  22 #include "hub.h"
  23
  24 static const struct attribute_group *port_dev_group[];
  25
  26 static ssize_t connect_type_show(struct device *dev,
  27                                  struct device_attribute *attr, char *buf)
  28 {
  29         struct usb_port *port_dev = to_usb_port(dev);
  30         char *result;
  31
  32         switch (port_dev->connect_type) {
  33         case USB_PORT_CONNECT_TYPE_HOT_PLUG:
  34                 result = "hotplug";
  35                 break;
  36         case USB_PORT_CONNECT_TYPE_HARD_WIRED:
  37                 result = "hardwired";
  38                 break;
  39         case USB_PORT_NOT_USED:
  40                 result = "not used";
  41                 break;
  42         default:
  43                 result = "unknown";
  44                 break;
  45         }
  46
  47         return sprintf(buf, "%s\n", result);
  48 }
  49 static DEVICE_ATTR_RO(connect_type);
  50
  51 static struct attribute *port_dev_attrs[] = {
  52         &dev_attr_connect_type.attr,
  53         NULL,
  54 };
  55
  56 static struct attribute_group port_dev_attr_grp = {
  57         .attrs = port_dev_attrs,
  58 };
  59
  60 static const struct attribute_group *port_dev_group[] = {
  61         &port_dev_attr_grp,
  62         NULL,
  63 };
  64
  65 static void usb_port_device_release(struct device *dev)
  66 {
  67         struct usb_port *port_dev = to_usb_port(dev);
  68
  69         kfree(port_dev);
  70 }
  71
  72 #ifdef CONFIG_PM_RUNTIME
  73 static int usb_port_runtime_resume(struct device *dev)
  74 {
  75         struct usb_port *port_dev = to_usb_port(dev);
  76         struct usb_device *hdev = to_usb_device(dev->parent->parent);
  77         struct usb_interface *intf = to_usb_interface(dev->parent);
  78         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
  79         int port1 = port_dev->portnum;
  80         int retval;
  81
  82         if (!hub)
  83                 return -EINVAL;
  84
  85         usb_autopm_get_interface(intf);
  86         set_bit(port1, hub->busy_bits);
  87
  88         retval = usb_hub_set_port_power(hdev, hub, port1, true);
  89         if (port_dev->child && !retval) {
  90                 /*
  91                  * Attempt to wait for usb hub port to be reconnected in order
  92                  * to make the resume procedure successful.  The device may have
  93                  * disconnected while the port was powered off, so ignore the
  94                  * return status.
  95                  */
  96                 retval = hub_port_debounce_be_connected(hub, port1);
  97                 if (retval < 0)
  98                         dev_dbg(&port_dev->dev, "can't get reconnection after setting port  power on, status %d\n",
  99                                         retval);
 100                 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
 101                 retval = 0;
 102         }
 103
 104         clear_bit(port1, hub->busy_bits);
 105         usb_autopm_put_interface(intf);
 106         return retval;
 107 }
 108
 109 static int usb_port_runtime_suspend(struct device *dev)
 110 {
 111         struct usb_port *port_dev = to_usb_port(dev);
 112         struct usb_device *hdev = to_usb_device(dev->parent->parent);
 113         struct usb_interface *intf = to_usb_interface(dev->parent);
 114         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 115         int port1 = port_dev->portnum;
 116         int retval;
 117
 118         if (!hub)
 119                 return -EINVAL;
 120
 121         if (dev_pm_qos_flags(&port_dev->dev, PM_QOS_FLAG_NO_POWER_OFF)
 122                         == PM_QOS_FLAGS_ALL)
 123                 return -EAGAIN;
 124
 125         usb_autopm_get_interface(intf);
 126         set_bit(port1, hub->busy_bits);
 127         retval = usb_hub_set_port_power(hdev, hub, port1, false);
 128         usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
 129         usb_clear_port_feature(hdev, port1,     USB_PORT_FEAT_C_ENABLE);
 130         clear_bit(port1, hub->busy_bits);
 131         usb_autopm_put_interface(intf);
 132         return retval;
 133 }
 134 #endif
 135
 136 static const struct dev_pm_ops usb_port_pm_ops = {
 137 #ifdef CONFIG_PM_RUNTIME
 138         .runtime_suspend =      usb_port_runtime_suspend,
 139         .runtime_resume =       usb_port_runtime_resume,
 140 #endif
 141 };
 142
 143 struct device_type usb_port_device_type = {
 144         .name =         "usb_port",
 145         .release =      usb_port_device_release,
 146         .pm =           &usb_port_pm_ops,
 147 };
 148
 149 int usb_hub_create_port_device(struct usb_hub *hub, int port1)
 150 {
 151         struct usb_port *port_dev = NULL;
 152         int retval;
 153
 154         port_dev = kzalloc(sizeof(*port_dev), GFP_KERNEL);
 155         if (!port_dev) {
 156                 retval = -ENOMEM;
 157                 goto exit;
 158         }
 159
 160         hub->ports[port1 - 1] = port_dev;
 161         port_dev->portnum = port1;
 162         port_dev->power_is_on = true;
 163         port_dev->dev.parent = hub->intfdev;
 164         port_dev->dev.groups = port_dev_group;
 165         port_dev->dev.type = &usb_port_device_type;
 166         dev_set_name(&port_dev->dev, "port%d", port1);
 167
 168         retval = device_register(&port_dev->dev);
 169         if (retval)
 170                 goto error_register;
 171
 172         pm_runtime_set_active(&port_dev->dev);
 173
 174         /* It would be dangerous if user space couldn't
 175          * prevent usb device from being powered off. So don't
 176          * enable port runtime pm if failed to expose port's pm qos.
 177          */
 178         if (!dev_pm_qos_expose_flags(&port_dev->dev,
 179                         PM_QOS_FLAG_NO_POWER_OFF))
 180                 pm_runtime_enable(&port_dev->dev);
 181
 182         device_enable_async_suspend(&port_dev->dev);
 183         return 0;
 184
 185 error_register:
 186         put_device(&port_dev->dev);
 187 exit:
 188         return retval;
 189 }
 190
 191 void usb_hub_remove_port_device(struct usb_hub *hub,
 192                                        int port1)
 193 {
 194         device_unregister(&hub->ports[port1 - 1]->dev);
 195 }
 196