xref: /linux/drivers/mfd/viperboard.c (revision f01312d846016dbd38cc9865e580298fb61f2aa7)
1 /*
2  *  Nano River Technologies viperboard driver
3  *
4  *  This is the core driver for the viperboard. There are cell drivers
5  *  available for I2C, ADC and both GPIOs. SPI is not yet supported.
6  *  The drivers do not support all features the board exposes. See user
7  *  manual of the viperboard.
8  *
9  *  (C) 2012 by Lemonage GmbH
10  *  Author: Lars Poeschel <poeschel@lemonage.de>
11  *  All rights reserved.
12  *
13  *  This program is free software; you can redistribute  it and/or modify it
14  *  under  the terms of  the GNU General  Public License as published by the
15  *  Free Software Foundation;  either version 2 of the  License, or (at your
16  *  option) any later version.
17  *
18  */
19 
20 #include <linux/kernel.h>
21 #include <linux/errno.h>
22 #include <linux/module.h>
23 #include <linux/slab.h>
24 #include <linux/types.h>
25 #include <linux/mutex.h>
26 
27 #include <linux/mfd/core.h>
28 #include <linux/mfd/viperboard.h>
29 
30 #include <linux/usb.h>
31 
32 
33 static const struct usb_device_id vprbrd_table[] = {
34 	{ USB_DEVICE(0x2058, 0x1005) },   /* Nano River Technologies */
35 	{ }                               /* Terminating entry */
36 };
37 
38 MODULE_DEVICE_TABLE(usb, vprbrd_table);
39 
40 static struct mfd_cell vprbrd_devs[] = {
41 };
42 
43 static int vprbrd_probe(struct usb_interface *interface,
44 			      const struct usb_device_id *id)
45 {
46 	struct vprbrd *vb;
47 
48 	u16 version = 0;
49 	int pipe, ret;
50 	unsigned char buf[1];
51 
52 	/* allocate memory for our device state and initialize it */
53 	vb = kzalloc(sizeof(*vb), GFP_KERNEL);
54 	if (vb == NULL) {
55 		dev_err(&interface->dev, "Out of memory\n");
56 		return -ENOMEM;
57 	}
58 
59 	mutex_init(&vb->lock);
60 
61 	vb->usb_dev = usb_get_dev(interface_to_usbdev(interface));
62 
63 	/* save our data pointer in this interface device */
64 	usb_set_intfdata(interface, vb);
65 	dev_set_drvdata(&vb->pdev.dev, vb);
66 
67 	/* get version information, major first, minor then */
68 	pipe = usb_rcvctrlpipe(vb->usb_dev, 0);
69 	ret = usb_control_msg(vb->usb_dev, pipe, VPRBRD_USB_REQUEST_MAJOR,
70 		VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, buf, 1,
71 		VPRBRD_USB_TIMEOUT_MS);
72 	if (ret == 1)
73 		version = buf[0];
74 
75 	ret = usb_control_msg(vb->usb_dev, pipe, VPRBRD_USB_REQUEST_MINOR,
76 		VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, buf, 1,
77 		VPRBRD_USB_TIMEOUT_MS);
78 	if (ret == 1) {
79 		version <<= 8;
80 		version = version | buf[0];
81 	}
82 
83 	dev_info(&interface->dev,
84 		 "version %x.%02x found at bus %03d address %03d\n",
85 		 version >> 8, version & 0xff,
86 		 vb->usb_dev->bus->busnum, vb->usb_dev->devnum);
87 
88 	ret = mfd_add_devices(&interface->dev, -1, vprbrd_devs,
89 				ARRAY_SIZE(vprbrd_devs), NULL, 0, NULL);
90 	if (ret != 0) {
91 		dev_err(&interface->dev, "Failed to add mfd devices to core.");
92 		goto error;
93 	}
94 
95 	return 0;
96 
97 error:
98 	if (vb) {
99 		usb_put_dev(vb->usb_dev);
100 		kfree(vb);
101 	}
102 
103 	return ret;
104 }
105 
106 static void vprbrd_disconnect(struct usb_interface *interface)
107 {
108 	struct vprbrd *vb = usb_get_intfdata(interface);
109 
110 	mfd_remove_devices(&interface->dev);
111 	usb_set_intfdata(interface, NULL);
112 	usb_put_dev(vb->usb_dev);
113 	kfree(vb);
114 
115 	dev_dbg(&interface->dev, "disconnected\n");
116 }
117 
118 static struct usb_driver vprbrd_driver = {
119 	.name		= "viperboard",
120 	.probe		= vprbrd_probe,
121 	.disconnect	= vprbrd_disconnect,
122 	.id_table	= vprbrd_table,
123 };
124 
125 module_usb_driver(vprbrd_driver);
126 
127 MODULE_DESCRIPTION("Nano River Technologies viperboard mfd core driver");
128 MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
129 MODULE_LICENSE("GPL");
130