drivers/mfd/viperboard.c

Source file repositories/reference/linux-study-clean/drivers/mfd/viperboard.c

File Facts

System
Linux kernel
Corpus path
drivers/mfd/viperboard.c
Extension
.c
Size
3055 bytes
Lines
128
Domain
Driver Families
Bucket
drivers/mfd
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// 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_obj(*vb);
	if (!vb)
		return -ENOMEM;

	mutex_init(&vb->lock);

	vb->usb_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\n",
		 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));

Annotation

Implementation Notes