1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * comedi_usb.c
4 * Comedi USB driver specific functions.
5 *
6 * COMEDI - Linux Control and Measurement Device Interface
7 * Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
8 */
9
10 #include <linux/module.h>
11 #include <linux/comedi/comedi_usb.h>
12
13 /**
14 * comedi_to_usb_interface() - Return USB interface attached to COMEDI device
15 * @dev: COMEDI device.
16 *
17 * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
18 * a &struct device embedded in a &struct usb_interface.
19 *
20 * Return: Attached USB interface if @dev->hw_dev is non-%NULL.
21 * Return %NULL if @dev->hw_dev is %NULL.
22 */
comedi_to_usb_interface(struct comedi_device * dev)23 struct usb_interface *comedi_to_usb_interface(struct comedi_device *dev)
24 {
25 return dev->hw_dev ? to_usb_interface(dev->hw_dev) : NULL;
26 }
27 EXPORT_SYMBOL_GPL(comedi_to_usb_interface);
28
29 /**
30 * comedi_to_usb_dev() - Return USB device attached to COMEDI device
31 * @dev: COMEDI device.
32 *
33 * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
34 * a &struct device embedded in a &struct usb_interface.
35 *
36 * Return: USB device to which the USB interface belongs if @dev->hw_dev is
37 * non-%NULL. Return %NULL if @dev->hw_dev is %NULL.
38 */
comedi_to_usb_dev(struct comedi_device * dev)39 struct usb_device *comedi_to_usb_dev(struct comedi_device *dev)
40 {
41 struct usb_interface *intf = comedi_to_usb_interface(dev);
42
43 return intf ? interface_to_usbdev(intf) : NULL;
44 }
45 EXPORT_SYMBOL_GPL(comedi_to_usb_dev);
46
47 /**
48 * comedi_usb_auto_config() - Configure/probe a USB COMEDI driver
49 * @intf: USB interface.
50 * @driver: Registered COMEDI driver.
51 * @context: Driver specific data, passed to comedi_auto_config().
52 *
53 * Typically called from the usb_driver (*probe) function. Auto-configure a
54 * COMEDI device, using a pointer to the &struct device embedded in *@intf as
55 * the hardware device. The @context value gets passed through to @driver's
56 * "auto_attach" handler. The "auto_attach" handler may call
57 * comedi_to_usb_interface() on the passed in COMEDI device to recover @intf.
58 *
59 * Return: The result of calling comedi_auto_config() (%0 on success, or
60 * a negative error number on failure).
61 */
comedi_usb_auto_config(struct usb_interface * intf,struct comedi_driver * driver,unsigned long context)62 int comedi_usb_auto_config(struct usb_interface *intf,
63 struct comedi_driver *driver,
64 unsigned long context)
65 {
66 return comedi_auto_config(&intf->dev, driver, context);
67 }
68 EXPORT_SYMBOL_GPL(comedi_usb_auto_config);
69
70 /**
71 * comedi_usb_auto_unconfig() - Unconfigure/disconnect a USB COMEDI device
72 * @intf: USB interface.
73 *
74 * Typically called from the usb_driver (*disconnect) function.
75 * Auto-unconfigure a COMEDI device attached to this USB interface, using a
76 * pointer to the &struct device embedded in *@intf as the hardware device.
77 * The COMEDI driver's "detach" handler will be called during unconfiguration
78 * of the COMEDI device.
79 *
80 * Note that the COMEDI device may have already been unconfigured using the
81 * %COMEDI_DEVCONFIG ioctl, in which case this attempt to unconfigure it
82 * again should be ignored.
83 */
comedi_usb_auto_unconfig(struct usb_interface * intf)84 void comedi_usb_auto_unconfig(struct usb_interface *intf)
85 {
86 comedi_auto_unconfig(&intf->dev);
87 }
88 EXPORT_SYMBOL_GPL(comedi_usb_auto_unconfig);
89
90 /**
91 * comedi_usb_driver_register() - Register a USB COMEDI driver
92 * @comedi_driver: COMEDI driver to be registered.
93 * @usb_driver: USB driver to be registered.
94 *
95 * This function is called from the module_init() of USB COMEDI driver modules
96 * to register the COMEDI driver and the USB driver. Do not call it directly,
97 * use the module_comedi_usb_driver() helper macro instead.
98 *
99 * Return: %0 on success, or a negative error number on failure.
100 */
comedi_usb_driver_register(struct comedi_driver * comedi_driver,struct usb_driver * usb_driver)101 int comedi_usb_driver_register(struct comedi_driver *comedi_driver,
102 struct usb_driver *usb_driver)
103 {
104 int ret;
105
106 ret = comedi_driver_register(comedi_driver);
107 if (ret < 0)
108 return ret;
109
110 ret = usb_register(usb_driver);
111 if (ret < 0) {
112 comedi_driver_unregister(comedi_driver);
113 return ret;
114 }
115
116 return 0;
117 }
118 EXPORT_SYMBOL_GPL(comedi_usb_driver_register);
119
120 /**
121 * comedi_usb_driver_unregister() - Unregister a USB COMEDI driver
122 * @comedi_driver: COMEDI driver to be registered.
123 * @usb_driver: USB driver to be registered.
124 *
125 * This function is called from the module_exit() of USB COMEDI driver modules
126 * to unregister the USB driver and the COMEDI driver. Do not call it
127 * directly, use the module_comedi_usb_driver() helper macro instead.
128 */
comedi_usb_driver_unregister(struct comedi_driver * comedi_driver,struct usb_driver * usb_driver)129 void comedi_usb_driver_unregister(struct comedi_driver *comedi_driver,
130 struct usb_driver *usb_driver)
131 {
132 usb_deregister(usb_driver);
133 comedi_driver_unregister(comedi_driver);
134 }
135 EXPORT_SYMBOL_GPL(comedi_usb_driver_unregister);
136
comedi_usb_init(void)137 static int __init comedi_usb_init(void)
138 {
139 return 0;
140 }
141 module_init(comedi_usb_init);
142
comedi_usb_exit(void)143 static void __exit comedi_usb_exit(void)
144 {
145 }
146 module_exit(comedi_usb_exit);
147
148 MODULE_AUTHOR("https://www.comedi.org");
149 MODULE_DESCRIPTION("Comedi USB interface module");
150 MODULE_LICENSE("GPL");
151