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
 33static const struct usb_device_id vprbrd_table[] = {
 34	{ USB_DEVICE(0x2058, 0x1005) },   /* Nano River Technologies */
 35	{ }                               /* Terminating entry */
 36};
 37
 38MODULE_DEVICE_TABLE(usb, vprbrd_table);
 39
 40static const struct mfd_cell vprbrd_devs[] = {
 41	{
 42		.name = "viperboard-gpio",
 43	},
 44	{
 45		.name = "viperboard-i2c",
 46	},
 47	{
 48		.name = "viperboard-adc",
 49	},
 50};
 51
 52static int vprbrd_probe(struct usb_interface *interface,
 53			      const struct usb_device_id *id)
 54{
 55	struct vprbrd *vb;
 56
 57	u16 version = 0;
 58	int pipe, ret;
 59
 60	/* allocate memory for our device state and initialize it */
 61	vb = kzalloc(sizeof(*vb), GFP_KERNEL);
 62	if (vb == NULL) {
 63		dev_err(&interface->dev, "Out of memory\n");
 64		return -ENOMEM;
 65	}
 66
 67	mutex_init(&vb->lock);
 68
 69	vb->usb_dev = usb_get_dev(interface_to_usbdev(interface));
 70
 71	/* save our data pointer in this interface device */
 72	usb_set_intfdata(interface, vb);
 73	dev_set_drvdata(&vb->pdev.dev, vb);
 74
 75	/* get version information, major first, minor then */
 76	pipe = usb_rcvctrlpipe(vb->usb_dev, 0);
 77	ret = usb_control_msg(vb->usb_dev, pipe, VPRBRD_USB_REQUEST_MAJOR,
 78		VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, vb->buf, 1,
 79		VPRBRD_USB_TIMEOUT_MS);
 80	if (ret == 1)
 81		version = vb->buf[0];
 82
 83	ret = usb_control_msg(vb->usb_dev, pipe, VPRBRD_USB_REQUEST_MINOR,
 84		VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, vb->buf, 1,
 85		VPRBRD_USB_TIMEOUT_MS);
 86	if (ret == 1) {
 87		version <<= 8;
 88		version = version | vb->buf[0];
 89	}
 90
 91	dev_info(&interface->dev,
 92		 "version %x.%02x found at bus %03d address %03d\n",
 93		 version >> 8, version & 0xff,
 94		 vb->usb_dev->bus->busnum, vb->usb_dev->devnum);
 95
 96	ret = mfd_add_hotplug_devices(&interface->dev, vprbrd_devs,
 97				      ARRAY_SIZE(vprbrd_devs));
 98	if (ret != 0) {
 99		dev_err(&interface->dev, "Failed to add mfd devices to core.");
100		goto error;
101	}
102
103	return 0;
104
105error:
106	if (vb) {
107		usb_put_dev(vb->usb_dev);
108		kfree(vb);
109	}
110
111	return ret;
112}
113
114static void vprbrd_disconnect(struct usb_interface *interface)
115{
116	struct vprbrd *vb = usb_get_intfdata(interface);
117
118	mfd_remove_devices(&interface->dev);
119	usb_set_intfdata(interface, NULL);
120	usb_put_dev(vb->usb_dev);
121	kfree(vb);
122
123	dev_dbg(&interface->dev, "disconnected\n");
124}
125
126static struct usb_driver vprbrd_driver = {
127	.name		= "viperboard",
128	.probe		= vprbrd_probe,
129	.disconnect	= vprbrd_disconnect,
130	.id_table	= vprbrd_table,
131};
132
133module_usb_driver(vprbrd_driver);
134
135MODULE_DESCRIPTION("Nano River Technologies viperboard mfd core driver");
136MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
137MODULE_LICENSE("GPL");