1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Nano River Technologies viperboard driver
4 *
5 * This is the core driver for the viperboard. There are cell drivers
6 * available for I2C, ADC and both GPIOs. SPI is not yet supported.
7 * The drivers do not support all features the board exposes. See user
8 * manual of the viperboard.
9 *
10 * (C) 2012 by Lemonage GmbH
11 * Author: Lars Poeschel <poeschel@lemonage.de>
12 * All rights reserved.
13 */
14
15#include <linux/kernel.h>
16#include <linux/errno.h>
17#include <linux/module.h>
18#include <linux/slab.h>
19#include <linux/types.h>
20#include <linux/mutex.h>
21
22#include <linux/mfd/core.h>
23#include <linux/mfd/viperboard.h>
24
25#include <linux/usb.h>
26
27
28static const struct usb_device_id vprbrd_table[] = {
29 { USB_DEVICE(0x2058, 0x1005) }, /* Nano River Technologies */
30 { } /* Terminating entry */
31};
32
33MODULE_DEVICE_TABLE(usb, vprbrd_table);
34
35static const struct mfd_cell vprbrd_devs[] = {
36 {
37 .name = "viperboard-gpio",
38 },
39 {
40 .name = "viperboard-i2c",
41 },
42 {
43 .name = "viperboard-adc",
44 },
45};
46
47static int vprbrd_probe(struct usb_interface *interface,
48 const struct usb_device_id *id)
49{
50 struct vprbrd *vb;
51
52 u16 version = 0;
53 int pipe, ret;
54
55 /* allocate memory for our device state and initialize it */
56 vb = kzalloc(size: sizeof(*vb), GFP_KERNEL);
57 if (!vb)
58 return -ENOMEM;
59
60 mutex_init(&vb->lock);
61
62 vb->usb_dev = usb_get_dev(interface_to_usbdev(interface));
63
64 /* save our data pointer in this interface device */
65 usb_set_intfdata(intf: interface, data: vb);
66 dev_set_drvdata(dev: &vb->pdev.dev, data: vb);
67
68 /* get version information, major first, minor then */
69 pipe = usb_rcvctrlpipe(vb->usb_dev, 0);
70 ret = usb_control_msg(dev: vb->usb_dev, pipe, VPRBRD_USB_REQUEST_MAJOR,
71 VPRBRD_USB_TYPE_IN, value: 0x0000, index: 0x0000, data: vb->buf, size: 1,
72 VPRBRD_USB_TIMEOUT_MS);
73 if (ret == 1)
74 version = vb->buf[0];
75
76 ret = usb_control_msg(dev: vb->usb_dev, pipe, VPRBRD_USB_REQUEST_MINOR,
77 VPRBRD_USB_TYPE_IN, value: 0x0000, index: 0x0000, data: vb->buf, size: 1,
78 VPRBRD_USB_TIMEOUT_MS);
79 if (ret == 1) {
80 version <<= 8;
81 version = version | vb->buf[0];
82 }
83
84 dev_info(&interface->dev,
85 "version %x.%02x found at bus %03d address %03d\n",
86 version >> 8, version & 0xff,
87 vb->usb_dev->bus->busnum, vb->usb_dev->devnum);
88
89 ret = mfd_add_hotplug_devices(parent: &interface->dev, cells: vprbrd_devs,
90 ARRAY_SIZE(vprbrd_devs));
91 if (ret != 0) {
92 dev_err(&interface->dev, "Failed to add mfd devices to core.");
93 goto error;
94 }
95
96 return 0;
97
98error:
99 if (vb) {
100 usb_put_dev(dev: vb->usb_dev);
101 kfree(objp: vb);
102 }
103
104 return ret;
105}
106
107static void vprbrd_disconnect(struct usb_interface *interface)
108{
109 struct vprbrd *vb = usb_get_intfdata(intf: interface);
110
111 mfd_remove_devices(parent: &interface->dev);
112 usb_set_intfdata(intf: interface, NULL);
113 usb_put_dev(dev: vb->usb_dev);
114 kfree(objp: vb);
115
116 dev_dbg(&interface->dev, "disconnected\n");
117}
118
119static struct usb_driver vprbrd_driver = {
120 .name = "viperboard",
121 .probe = vprbrd_probe,
122 .disconnect = vprbrd_disconnect,
123 .id_table = vprbrd_table,
124};
125
126module_usb_driver(vprbrd_driver);
127
128MODULE_DESCRIPTION("Nano River Technologies viperboard mfd core driver");
129MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
130MODULE_LICENSE("GPL");
131

source code of linux/drivers/mfd/viperboard.c