xref: /openbmc/linux/drivers/usb/core/port.c (revision 8e9356c6)
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 
197