1 /* 2 * USB-ACPI glue code 3 * 4 * Copyright 2012 Red Hat <mjg@redhat.com> 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License as published by the Free 8 * Software Foundation, version 2. 9 * 10 */ 11 #include <linux/module.h> 12 #include <linux/usb.h> 13 #include <linux/device.h> 14 #include <linux/errno.h> 15 #include <linux/kernel.h> 16 #include <linux/acpi.h> 17 #include <linux/pci.h> 18 #include <linux/usb/hcd.h> 19 #include <acpi/acpi_bus.h> 20 21 #include "usb.h" 22 23 /** 24 * usb_acpi_power_manageable - check whether usb port has 25 * acpi power resource. 26 * @hdev: USB device belonging to the usb hub 27 * @index: port index based zero 28 * 29 * Return true if the port has acpi power resource and false if no. 30 */ 31 bool usb_acpi_power_manageable(struct usb_device *hdev, int index) 32 { 33 acpi_handle port_handle; 34 int port1 = index + 1; 35 36 port_handle = usb_get_hub_port_acpi_handle(hdev, 37 port1); 38 if (port_handle) 39 return acpi_bus_power_manageable(port_handle); 40 else 41 return false; 42 } 43 EXPORT_SYMBOL_GPL(usb_acpi_power_manageable); 44 45 /** 46 * usb_acpi_set_power_state - control usb port's power via acpi power 47 * resource 48 * @hdev: USB device belonging to the usb hub 49 * @index: port index based zero 50 * @enable: power state expected to be set 51 * 52 * Notice to use usb_acpi_power_manageable() to check whether the usb port 53 * has acpi power resource before invoking this function. 54 * 55 * Returns 0 on success, else negative errno. 56 */ 57 int usb_acpi_set_power_state(struct usb_device *hdev, int index, bool enable) 58 { 59 acpi_handle port_handle; 60 unsigned char state; 61 int port1 = index + 1; 62 int error = -EINVAL; 63 64 port_handle = (acpi_handle)usb_get_hub_port_acpi_handle(hdev, 65 port1); 66 if (!port_handle) 67 return error; 68 69 if (enable) 70 state = ACPI_STATE_D0; 71 else 72 state = ACPI_STATE_D3_COLD; 73 74 error = acpi_bus_set_power(port_handle, state); 75 if (!error) 76 dev_dbg(&hdev->dev, "The power of hub port %d was set to %d\n", 77 port1, enable); 78 else 79 dev_dbg(&hdev->dev, "The power of hub port failed to be set\n"); 80 81 return error; 82 } 83 EXPORT_SYMBOL_GPL(usb_acpi_set_power_state); 84 85 static int usb_acpi_check_port_connect_type(struct usb_device *hdev, 86 acpi_handle handle, int port1) 87 { 88 acpi_status status; 89 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 90 union acpi_object *upc; 91 struct acpi_pld_info *pld; 92 int ret = 0; 93 94 /* 95 * Accoding to ACPI Spec 9.13. PLD indicates whether usb port is 96 * user visible and _UPC indicates whether it is connectable. If 97 * the port was visible and connectable, it could be freely connected 98 * and disconnected with USB devices. If no visible and connectable, 99 * a usb device is directly hard-wired to the port. If no visible and 100 * no connectable, the port would be not used. 101 */ 102 status = acpi_get_physical_device_location(handle, &pld); 103 if (ACPI_FAILURE(status)) 104 return -ENODEV; 105 106 status = acpi_evaluate_object(handle, "_UPC", NULL, &buffer); 107 upc = buffer.pointer; 108 if (!upc || (upc->type != ACPI_TYPE_PACKAGE) 109 || upc->package.count != 4) { 110 ret = -EINVAL; 111 goto out; 112 } 113 114 if (upc->package.elements[0].integer.value) 115 if (pld->user_visible) 116 usb_set_hub_port_connect_type(hdev, port1, 117 USB_PORT_CONNECT_TYPE_HOT_PLUG); 118 else 119 usb_set_hub_port_connect_type(hdev, port1, 120 USB_PORT_CONNECT_TYPE_HARD_WIRED); 121 else if (!pld->user_visible) 122 usb_set_hub_port_connect_type(hdev, port1, USB_PORT_NOT_USED); 123 124 out: 125 ACPI_FREE(pld); 126 kfree(upc); 127 return ret; 128 } 129 130 static int usb_acpi_find_device(struct device *dev, acpi_handle *handle) 131 { 132 struct usb_device *udev; 133 acpi_handle *parent_handle; 134 int port_num; 135 136 /* 137 * In the ACPI DSDT table, only usb root hub and usb ports are 138 * acpi device nodes. The hierarchy like following. 139 * Device (EHC1) 140 * Device (HUBN) 141 * Device (PR01) 142 * Device (PR11) 143 * Device (PR12) 144 * Device (PR13) 145 * ... 146 * So all binding process is divided into two parts. binding 147 * root hub and usb ports. 148 */ 149 if (is_usb_device(dev)) { 150 udev = to_usb_device(dev); 151 if (udev->parent) { 152 enum usb_port_connect_type type; 153 154 /* 155 * According usb port's connect type to set usb device's 156 * removability. 157 */ 158 type = usb_get_hub_port_connect_type(udev->parent, 159 udev->portnum); 160 switch (type) { 161 case USB_PORT_CONNECT_TYPE_HOT_PLUG: 162 udev->removable = USB_DEVICE_REMOVABLE; 163 break; 164 case USB_PORT_CONNECT_TYPE_HARD_WIRED: 165 udev->removable = USB_DEVICE_FIXED; 166 break; 167 default: 168 udev->removable = USB_DEVICE_REMOVABLE_UNKNOWN; 169 break; 170 } 171 172 return -ENODEV; 173 } 174 175 /* root hub's parent is the usb hcd. */ 176 parent_handle = DEVICE_ACPI_HANDLE(dev->parent); 177 *handle = acpi_get_child(parent_handle, udev->portnum); 178 if (!*handle) 179 return -ENODEV; 180 return 0; 181 } else if (is_usb_port(dev)) { 182 sscanf(dev_name(dev), "port%d", &port_num); 183 /* Get the struct usb_device point of port's hub */ 184 udev = to_usb_device(dev->parent->parent); 185 186 /* 187 * The root hub ports' parent is the root hub. The non-root-hub 188 * ports' parent is the parent hub port which the hub is 189 * connected to. 190 */ 191 if (!udev->parent) { 192 struct usb_hcd *hcd = bus_to_hcd(udev->bus); 193 int raw_port_num; 194 195 raw_port_num = usb_hcd_find_raw_port_number(hcd, 196 port_num); 197 *handle = acpi_get_child(DEVICE_ACPI_HANDLE(&udev->dev), 198 raw_port_num); 199 if (!*handle) 200 return -ENODEV; 201 } else { 202 parent_handle = 203 usb_get_hub_port_acpi_handle(udev->parent, 204 udev->portnum); 205 if (!parent_handle) 206 return -ENODEV; 207 208 *handle = acpi_get_child(parent_handle, port_num); 209 if (!*handle) 210 return -ENODEV; 211 } 212 usb_acpi_check_port_connect_type(udev, *handle, port_num); 213 } else 214 return -ENODEV; 215 216 return 0; 217 } 218 219 static bool usb_acpi_bus_match(struct device *dev) 220 { 221 return is_usb_device(dev) || is_usb_port(dev); 222 } 223 224 static struct acpi_bus_type usb_acpi_bus = { 225 .name = "USB", 226 .match = usb_acpi_bus_match, 227 .find_device = usb_acpi_find_device, 228 }; 229 230 int usb_acpi_register(void) 231 { 232 return register_acpi_bus_type(&usb_acpi_bus); 233 } 234 235 void usb_acpi_unregister(void) 236 { 237 unregister_acpi_bus_type(&usb_acpi_bus); 238 } 239