// SPDX-License-Identifier: GPL-2.0-or-later

  /*
   *  Nano River Technologies viperboard driver
   *
   *  This is the core driver for the viperboard. There are cell drivers
   *  available for I2C, ADC and both GPIOs. SPI is not yet supported.
   *  The drivers do not support all features the board exposes. See user
   *  manual of the viperboard.
   *
   *  (C) 2012 by Lemonage GmbH
   *  Author: Lars Poeschel <poeschel@lemonage.de>
   *  All rights reserved.

   */
  
  #include <linux/kernel.h>
  #include <linux/errno.h>
  #include <linux/module.h>
  #include <linux/slab.h>
  #include <linux/types.h>
  #include <linux/mutex.h>
  
  #include <linux/mfd/core.h>
  #include <linux/mfd/viperboard.h>
  
  #include <linux/usb.h>
  
  
  static const struct usb_device_id vprbrd_table[] = {
  	{ USB_DEVICE(0x2058, 0x1005) },   /* Nano River Technologies */
  	{ }                               /* Terminating entry */
  };
  
  MODULE_DEVICE_TABLE(usb, vprbrd_table);

  static const struct mfd_cell vprbrd_devs[] = {

  	{
  		.name = "viperboard-gpio",
  	},

  	{
  		.name = "viperboard-i2c",
  	},

  	{
  		.name = "viperboard-adc",
  	},

  };
  
  static int vprbrd_probe(struct usb_interface *interface,
  			      const struct usb_device_id *id)
  {
  	struct vprbrd *vb;
  
  	u16 version = 0;
  	int pipe, ret;

  
  	/* allocate memory for our device state and initialize it */
  	vb = kzalloc(sizeof(*vb), GFP_KERNEL);

  	if (!vb)

  		return -ENOMEM;

  
  	mutex_init(&vb->lock);
  
  	vb->usb_dev = usb_get_dev(interface_to_usbdev(interface));
  
  	/* save our data pointer in this interface device */
  	usb_set_intfdata(interface, vb);
  	dev_set_drvdata(&vb->pdev.dev, vb);
  
  	/* get version information, major first, minor then */
  	pipe = usb_rcvctrlpipe(vb->usb_dev, 0);
  	ret = usb_control_msg(vb->usb_dev, pipe, VPRBRD_USB_REQUEST_MAJOR,

  		VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, vb->buf, 1,

  		VPRBRD_USB_TIMEOUT_MS);
  	if (ret == 1)

  		version = vb->buf[0];

  
  	ret = usb_control_msg(vb->usb_dev, pipe, VPRBRD_USB_REQUEST_MINOR,

  		VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, vb->buf, 1,

  		VPRBRD_USB_TIMEOUT_MS);
  	if (ret == 1) {
  		version <<= 8;

  		version = version | vb->buf[0];

  	}
  
  	dev_info(&interface->dev,
  		 "version %x.%02x found at bus %03d address %03d
  ",
  		 version >> 8, version & 0xff,
  		 vb->usb_dev->bus->busnum, vb->usb_dev->devnum);

  	ret = mfd_add_hotplug_devices(&interface->dev, vprbrd_devs,
  				      ARRAY_SIZE(vprbrd_devs));

  	if (ret != 0) {
  		dev_err(&interface->dev, "Failed to add mfd devices to core.");
  		goto error;
  	}
  
  	return 0;
  
  error:
  	if (vb) {
  		usb_put_dev(vb->usb_dev);
  		kfree(vb);
  	}
  
  	return ret;
  }
  
  static void vprbrd_disconnect(struct usb_interface *interface)
  {
  	struct vprbrd *vb = usb_get_intfdata(interface);
  
  	mfd_remove_devices(&interface->dev);
  	usb_set_intfdata(interface, NULL);
  	usb_put_dev(vb->usb_dev);
  	kfree(vb);
  
  	dev_dbg(&interface->dev, "disconnected
  ");
  }
  
  static struct usb_driver vprbrd_driver = {
  	.name		= "viperboard",
  	.probe		= vprbrd_probe,
  	.disconnect	= vprbrd_disconnect,
  	.id_table	= vprbrd_table,
  };
  
  module_usb_driver(vprbrd_driver);
  
  MODULE_DESCRIPTION("Nano River Technologies viperboard mfd core driver");
  MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
  MODULE_LICENSE("GPL");