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 show_port_connect_type(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(connect_type, S_IRUGO, show_port_connect_type,
  50                 NULL);
  51
  52 static struct attribute *port_dev_attrs[] = {
  53         &dev_attr_connect_type.attr,
  54         NULL,
  55 };
  56
  57 static struct attribute_group port_dev_attr_grp = {
  58         .attrs = port_dev_attrs,
  59 };
  60
  61 static const struct attribute_group *port_dev_group[] = {
  62         &port_dev_attr_grp,
  63         NULL,
  64 };
  65
  66 static void usb_port_device_release(struct device *dev)
  67 {
  68         struct usb_port *port_dev = to_usb_port(dev);
  69
  70         dev_pm_qos_hide_flags(dev);
  71         kfree(port_dev);
  72 }
  73
  74 #ifdef CONFIG_USB_SUSPEND
  75 static int usb_port_runtime_resume(struct device *dev)
  76 {
  77         struct usb_port *port_dev = to_usb_port(dev);
  78         struct usb_device *hdev = to_usb_device(dev->parent->parent);
  79         struct usb_interface *intf = to_usb_interface(dev->parent);
  80         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
  81         int port1 = port_dev->portnum;
  82         int retval;
  83
  84         if (!hub)
  85                 return -EINVAL;
  86
  87         usb_autopm_get_interface(intf);
  88         set_bit(port1, hub->busy_bits);
  89
  90         retval = usb_hub_set_port_power(hdev, port1, true);
  91         if (port_dev->child && !retval) {
  92                 /*
  93                  * Wait for usb hub port to be reconnected in order to make
  94                  * the resume procedure successful.
  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                         goto out;
 101                 }
 102                 usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
 103
 104                 /* Set return value to 0 if debounce successful */
 105                 retval = 0;
 106         }
 107
 108 out:
 109         clear_bit(port1, hub->busy_bits);
 110         usb_autopm_put_interface(intf);
 111         return retval;
 112 }
 113
 114 static int usb_port_runtime_suspend(struct device *dev)
 115 {
 116         struct usb_port *port_dev = to_usb_port(dev);
 117         struct usb_device *hdev = to_usb_device(dev->parent->parent);
 118         struct usb_interface *intf = to_usb_interface(dev->parent);
 119         struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 120         int port1 = port_dev->portnum;
 121         int retval;
 122
 123         if (!hub)
 124                 return -EINVAL;
 125
 126         if (dev_pm_qos_flags(&port_dev->dev, PM_QOS_FLAG_NO_POWER_OFF)
 127                         == PM_QOS_FLAGS_ALL)
 128                 return -EAGAIN;
 129
 130         usb_autopm_get_interface(intf);
 131         set_bit(port1, hub->busy_bits);
 132         retval = usb_hub_set_port_power(hdev, port1, false);
 133         usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
 134         usb_clear_port_feature(hdev, port1,     USB_PORT_FEAT_C_ENABLE);
 135         clear_bit(port1, hub->busy_bits);
 136         usb_autopm_put_interface(intf);
 137         return retval;
 138 }
 139 #endif
 140
 141 static const struct dev_pm_ops usb_port_pm_ops = {
 142 #ifdef CONFIG_USB_SUSPEND
 143         .runtime_suspend =      usb_port_runtime_suspend,
 144         .runtime_resume =       usb_port_runtime_resume,
 145         .runtime_idle =         pm_generic_runtime_idle,
 146 #endif
 147 };
 148
 149 struct device_type usb_port_device_type = {
 150         .name =         "usb_port",
 151         .release =      usb_port_device_release,
 152         .pm =           &usb_port_pm_ops,
 153 };
 154
 155 int usb_hub_create_port_device(struct usb_hub *hub, int port1)
 156 {
 157         struct usb_port *port_dev = NULL;
 158         int retval;
 159
 160         port_dev = kzalloc(sizeof(*port_dev), GFP_KERNEL);
 161         if (!port_dev) {
 162                 retval = -ENOMEM;
 163                 goto exit;
 164         }
 165
 166         hub->ports[port1 - 1] = port_dev;
 167         port_dev->portnum = port1;
 168         port_dev->power_is_on = true;
 169         port_dev->dev.parent = hub->intfdev;
 170         port_dev->dev.groups = port_dev_group;
 171         port_dev->dev.type = &usb_port_device_type;
 172         dev_set_name(&port_dev->dev, "port%d", port1);
 173
 174         retval = device_register(&port_dev->dev);
 175         if (retval)
 176                 goto error_register;
 177
 178         pm_runtime_set_active(&port_dev->dev);
 179
 180         /* It would be dangerous if user space couldn't
 181          * prevent usb device from being powered off. So don't
 182          * enable port runtime pm if failed to expose port's pm qos.
 183          */
 184         if (!dev_pm_qos_expose_flags(&port_dev->dev,
 185                         PM_QOS_FLAG_NO_POWER_OFF))
 186                 pm_runtime_enable(&port_dev->dev);
 187
 188         device_enable_async_suspend(&port_dev->dev);
 189         return 0;
 190
 191 error_register:
 192         put_device(&port_dev->dev);
 193 exit:
 194         return retval;
 195 }
 196
 197 void usb_hub_remove_port_device(struct usb_hub *hub,
 198                                        int port1)
 199 {
 200         device_unregister(&hub->ports[port1 - 1]->dev);
 201 }
 202