[mirror_ubuntu-artful-kernel.git] / drivers / uio / uio_pci_generic.c

/* uio_pci_generic - generic UIO driver for PCI 2.3 devices
 *
 * Copyright (C) 2009 Red Hat, Inc.
 * Author: Michael S. Tsirkin <mst@redhat.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2.
 *
 * Since the driver does not declare any device ids, you must allocate
 * id and bind the device to the driver yourself.  For example:
 *
 * # echo "8086 10f5" > /sys/bus/pci/drivers/uio_pci_generic/new_id
 * # echo -n 0000:00:19.0 > /sys/bus/pci/drivers/e1000e/unbind
 * # echo -n 0000:00:19.0 > /sys/bus/pci/drivers/uio_pci_generic/bind
 * # ls -l /sys/bus/pci/devices/0000:00:19.0/driver
 * .../0000:00:19.0/driver -> ../../../bus/pci/drivers/uio_pci_generic
 *
 * Driver won't bind to devices which do not support the Interrupt Disable Bit
 * in the command register. All devices compliant to PCI 2.3 (circa 2002) and
 * all compliant PCI Express devices should support this bit.
 */

#include <linux/device.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/uio_driver.h>

#define DRIVER_VERSION	"0.01.0"
#define DRIVER_AUTHOR	"Michael S. Tsirkin <mst@redhat.com>"
#define DRIVER_DESC	"Generic UIO driver for PCI 2.3 devices"

struct uio_pci_generic_dev {
	struct uio_info info;
	struct pci_dev *pdev;
};

static inline struct uio_pci_generic_dev *
to_uio_pci_generic_dev(struct uio_info *info)
{
	return container_of(info, struct uio_pci_generic_dev, info);
}

/* Interrupt handler. Read/modify/write the command register to disable
 * the interrupt. */
static irqreturn_t irqhandler(int irq, struct uio_info *info)
{
	struct uio_pci_generic_dev *gdev = to_uio_pci_generic_dev(info);

	if (!pci_check_and_mask_intx(gdev->pdev))
		return IRQ_NONE;

	/* UIO core will signal the user process. */
	return IRQ_HANDLED;
}

static int probe(struct pci_dev *pdev,
			   const struct pci_device_id *id)
{
	struct uio_pci_generic_dev *gdev;
	int err;

	err = pci_enable_device(pdev);
	if (err) {
		dev_err(&pdev->dev, "%s: pci_enable_device failed: %d\n",
			__func__, err);
		return err;
	}

	if (pdev->irq && !pci_intx_mask_supported(pdev)) {
		err = -ENODEV;
		goto err_verify;
	}

	gdev = kzalloc(sizeof(struct uio_pci_generic_dev), GFP_KERNEL);
	if (!gdev) {
		err = -ENOMEM;
		goto err_alloc;
	}

	gdev->info.name = "uio_pci_generic";
	gdev->info.version = DRIVER_VERSION;
	gdev->pdev = pdev;
	if (pdev->irq) {
		gdev->info.irq = pdev->irq;
		gdev->info.irq_flags = IRQF_SHARED;
		gdev->info.handler = irqhandler;
	} else {
		dev_warn(&pdev->dev, "No IRQ assigned to device: "
			 "no support for interrupts?\n");
	}

	err = uio_register_device(&pdev->dev, &gdev->info);
	if (err)
		goto err_register;
	pci_set_drvdata(pdev, gdev);

	return 0;
err_register:
	kfree(gdev);
err_alloc:
err_verify:
	pci_disable_device(pdev);
	return err;
}

static void remove(struct pci_dev *pdev)
{
	struct uio_pci_generic_dev *gdev = pci_get_drvdata(pdev);

	uio_unregister_device(&gdev->info);
	pci_disable_device(pdev);
	kfree(gdev);
}

static struct pci_driver uio_pci_driver = {
	.name = "uio_pci_generic",
	.id_table = NULL, /* only dynamic id's */
	.probe = probe,
	.remove = remove,
};

module_pci_driver(uio_pci_driver);
MODULE_VERSION(DRIVER_VERSION);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
Commit	Line	Data
ccb86a69 MT	1	/* uio_pci_generic - generic UIO driver for PCI 2.3 devices
	2	*
	3	* Copyright (C) 2009 Red Hat, Inc.
	4	* Author: Michael S. Tsirkin <mst@redhat.com>
	5	*
	6	* This work is licensed under the terms of the GNU GPL, version 2.
	7	*
	8	* Since the driver does not declare any device ids, you must allocate
	9	* id and bind the device to the driver yourself. For example:
	10	*
	11	* # echo "8086 10f5" > /sys/bus/pci/drivers/uio_pci_generic/new_id
	12	* # echo -n 0000:00:19.0 > /sys/bus/pci/drivers/e1000e/unbind
	13	* # echo -n 0000:00:19.0 > /sys/bus/pci/drivers/uio_pci_generic/bind
	14	* # ls -l /sys/bus/pci/devices/0000:00:19.0/driver
	15	* .../0000:00:19.0/driver -> ../../../bus/pci/drivers/uio_pci_generic
	16	*
	17	* Driver won't bind to devices which do not support the Interrupt Disable Bit
	18	* in the command register. All devices compliant to PCI 2.3 (circa 2002) and
	19	* all compliant PCI Express devices should support this bit.
	20	*/
	21
	22	#include <linux/device.h>
	23	#include <linux/module.h>
	24	#include <linux/pci.h>
5a0e3ad6	25	#include <linux/slab.h>
ccb86a69	26	#include <linux/uio_driver.h>
ccb86a69 MT	27
	28	#define DRIVER_VERSION "0.01.0"
	29	#define DRIVER_AUTHOR "Michael S. Tsirkin <mst@redhat.com>"
	30	#define DRIVER_DESC "Generic UIO driver for PCI 2.3 devices"
	31
	32	struct uio_pci_generic_dev {
	33	struct uio_info info;
	34	struct pci_dev *pdev;
ccb86a69 MT	35	};
	36
	37	static inline struct uio_pci_generic_dev *
	38	to_uio_pci_generic_dev(struct uio_info *info)
	39	{
	40	return container_of(info, struct uio_pci_generic_dev, info);
	41	}
	42
	43	/* Interrupt handler. Read/modify/write the command register to disable
	44	* the interrupt. */
	45	static irqreturn_t irqhandler(int irq, struct uio_info *info)
	46	{
	47	struct uio_pci_generic_dev *gdev = to_uio_pci_generic_dev(info);
ccb86a69	48
2502dbdf JK	49	if (!pci_check_and_mask_intx(gdev->pdev))
2502dbdf JK	50	return IRQ_NONE;
ccb86a69 MT	51
ccb86a69 MT	52	/* UIO core will signal the user process. */
2502dbdf	53	return IRQ_HANDLED;
ccb86a69 MT	54	}
ccb86a69 MT	55
b17b75bb	56	static int probe(struct pci_dev *pdev,
ccb86a69 MT	57	const struct pci_device_id *id)
	58	{
	59	struct uio_pci_generic_dev *gdev;
	60	int err;
	61
ccb86a69 MT	62	err = pci_enable_device(pdev);
	63	if (err) {
	64	dev_err(&pdev->dev, "%s: pci_enable_device failed: %d\n",
	65	__func__, err);
	66	return err;
	67	}
	68
acec09e6	69	if (pdev->irq && !pci_intx_mask_supported(pdev)) {
2502dbdf	70	err = -ENODEV;
ccb86a69	71	goto err_verify;
2502dbdf	72	}
ccb86a69 MT	73
	74	gdev = kzalloc(sizeof(struct uio_pci_generic_dev), GFP_KERNEL);
	75	if (!gdev) {
	76	err = -ENOMEM;
	77	goto err_alloc;
	78	}
	79
	80	gdev->info.name = "uio_pci_generic";
	81	gdev->info.version = DRIVER_VERSION;
ccb86a69	82	gdev->pdev = pdev;
acec09e6 JH	83	if (pdev->irq) {
	84	gdev->info.irq = pdev->irq;
	85	gdev->info.irq_flags = IRQF_SHARED;
	86	gdev->info.handler = irqhandler;
	87	} else {
	88	dev_warn(&pdev->dev, "No IRQ assigned to device: "
	89	"no support for interrupts?\n");
	90	}
ccb86a69	91
c4277e9e AK	92	err = uio_register_device(&pdev->dev, &gdev->info);
c4277e9e AK	93	if (err)
ccb86a69 MT	94	goto err_register;
	95	pci_set_drvdata(pdev, gdev);
	96
	97	return 0;
	98	err_register:
	99	kfree(gdev);
	100	err_alloc:
	101	err_verify:
	102	pci_disable_device(pdev);
	103	return err;
	104	}
	105
	106	static void remove(struct pci_dev *pdev)
	107	{
	108	struct uio_pci_generic_dev *gdev = pci_get_drvdata(pdev);
	109
	110	uio_unregister_device(&gdev->info);
	111	pci_disable_device(pdev);
	112	kfree(gdev);
	113	}
	114
cd437398	115	static struct pci_driver uio_pci_driver = {
ccb86a69 MT	116	.name = "uio_pci_generic",
	117	.id_table = NULL, /* only dynamic id's */
	118	.probe = probe,
	119	.remove = remove,
	120	};
	121
cd437398	122	module_pci_driver(uio_pci_driver);
ccb86a69 MT	123	MODULE_VERSION(DRIVER_VERSION);
	124	MODULE_LICENSE("GPL v2");
	125	MODULE_AUTHOR(DRIVER_AUTHOR);
	126	MODULE_DESCRIPTION(DRIVER_DESC);