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(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(interface, vb);
 66	dev_set_drvdata(&vb->pdev.dev, vb);
 67
 68	/* get version information, major first, minor then */
 69	pipe = usb_rcvctrlpipe(vb->usb_dev, 0);
 70	ret = usb_control_msg(vb->usb_dev, pipe, VPRBRD_USB_REQUEST_MAJOR,
 71		VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, vb->buf, 1,
 72		VPRBRD_USB_TIMEOUT_MS);
 73	if (ret == 1)
 74		version = vb->buf[0];
 75
 76	ret = usb_control_msg(vb->usb_dev, pipe, VPRBRD_USB_REQUEST_MINOR,
 77		VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, vb->buf, 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(&interface->dev, 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(vb->usb_dev);
101		kfree(vb);
102	}
103
104	return ret;
105}
106
107static void vprbrd_disconnect(struct usb_interface *interface)
108{
109	struct vprbrd *vb = usb_get_intfdata(interface);
110
111	mfd_remove_devices(&interface->dev);
112	usb_set_intfdata(interface, NULL);
113	usb_put_dev(vb->usb_dev);
114	kfree(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");