xref: /openbmc/linux/drivers/usb/core/port.c (revision 97da55fc)
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 
203