xref: /openbmc/linux/drivers/usb/core/port.c (revision 39b6f3aa)
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 	kfree(port_dev);
71 }
72 
73 #ifdef CONFIG_PM_RUNTIME
74 static int usb_port_runtime_resume(struct device *dev)
75 {
76 	struct usb_port *port_dev = to_usb_port(dev);
77 	struct usb_device *hdev = to_usb_device(dev->parent->parent);
78 	struct usb_interface *intf = to_usb_interface(dev->parent);
79 	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
80 	int port1 = port_dev->portnum;
81 	int retval;
82 
83 	if (!hub)
84 		return -EINVAL;
85 
86 	usb_autopm_get_interface(intf);
87 	set_bit(port1, hub->busy_bits);
88 
89 	retval = usb_hub_set_port_power(hdev, port1, true);
90 	if (port_dev->child && !retval) {
91 		/*
92 		 * Wait for usb hub port to be reconnected in order to make
93 		 * the resume procedure successful.
94 		 */
95 		retval = hub_port_debounce_be_connected(hub, port1);
96 		if (retval < 0) {
97 			dev_dbg(&port_dev->dev, "can't get reconnection after setting port  power on, status %d\n",
98 					retval);
99 			goto out;
100 		}
101 		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
102 
103 		/* Set return value to 0 if debounce successful */
104 		retval = 0;
105 	}
106 
107 out:
108 	clear_bit(port1, hub->busy_bits);
109 	usb_autopm_put_interface(intf);
110 	return retval;
111 }
112 
113 static int usb_port_runtime_suspend(struct device *dev)
114 {
115 	struct usb_port *port_dev = to_usb_port(dev);
116 	struct usb_device *hdev = to_usb_device(dev->parent->parent);
117 	struct usb_interface *intf = to_usb_interface(dev->parent);
118 	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
119 	int port1 = port_dev->portnum;
120 	int retval;
121 
122 	if (!hub)
123 		return -EINVAL;
124 
125 	if (dev_pm_qos_flags(&port_dev->dev, PM_QOS_FLAG_NO_POWER_OFF)
126 			== PM_QOS_FLAGS_ALL)
127 		return -EAGAIN;
128 
129 	usb_autopm_get_interface(intf);
130 	set_bit(port1, hub->busy_bits);
131 	retval = usb_hub_set_port_power(hdev, port1, false);
132 	usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
133 	usb_clear_port_feature(hdev, port1,	USB_PORT_FEAT_C_ENABLE);
134 	clear_bit(port1, hub->busy_bits);
135 	usb_autopm_put_interface(intf);
136 	return retval;
137 }
138 #endif
139 
140 static const struct dev_pm_ops usb_port_pm_ops = {
141 #ifdef CONFIG_PM_RUNTIME
142 	.runtime_suspend =	usb_port_runtime_suspend,
143 	.runtime_resume =	usb_port_runtime_resume,
144 	.runtime_idle =		pm_generic_runtime_idle,
145 #endif
146 };
147 
148 struct device_type usb_port_device_type = {
149 	.name =		"usb_port",
150 	.release =	usb_port_device_release,
151 	.pm =		&usb_port_pm_ops,
152 };
153 
154 int usb_hub_create_port_device(struct usb_hub *hub, int port1)
155 {
156 	struct usb_port *port_dev = NULL;
157 	int retval;
158 
159 	port_dev = kzalloc(sizeof(*port_dev), GFP_KERNEL);
160 	if (!port_dev) {
161 		retval = -ENOMEM;
162 		goto exit;
163 	}
164 
165 	hub->ports[port1 - 1] = port_dev;
166 	port_dev->portnum = port1;
167 	port_dev->power_is_on = true;
168 	port_dev->dev.parent = hub->intfdev;
169 	port_dev->dev.groups = port_dev_group;
170 	port_dev->dev.type = &usb_port_device_type;
171 	dev_set_name(&port_dev->dev, "port%d", port1);
172 
173 	retval = device_register(&port_dev->dev);
174 	if (retval)
175 		goto error_register;
176 
177 	pm_runtime_set_active(&port_dev->dev);
178 
179 	/* It would be dangerous if user space couldn't
180 	 * prevent usb device from being powered off. So don't
181 	 * enable port runtime pm if failed to expose port's pm qos.
182 	 */
183 	if (!dev_pm_qos_expose_flags(&port_dev->dev,
184 			PM_QOS_FLAG_NO_POWER_OFF))
185 		pm_runtime_enable(&port_dev->dev);
186 
187 	device_enable_async_suspend(&port_dev->dev);
188 	return 0;
189 
190 error_register:
191 	put_device(&port_dev->dev);
192 exit:
193 	return retval;
194 }
195 
196 void usb_hub_remove_port_device(struct usb_hub *hub,
197 				       int port1)
198 {
199 	device_unregister(&hub->ports[port1 - 1]->dev);
200 }
201 
202