[deliverable/linux.git] / drivers / char / scx200_gpio.c

/* linux/drivers/char/scx200_gpio.c

   National Semiconductor SCx200 GPIO driver.  Allows a user space
   process to play with the GPIO pins.

   Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com> */

#include <linux/config.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <asm/uaccess.h>
#include <asm/io.h>

#include <linux/types.h>
#include <linux/cdev.h>

#include <linux/scx200_gpio.h>
#include <linux/nsc_gpio.h>

#define NAME "scx200_gpio"
#define DEVNAME NAME

static struct platform_device *pdev;

MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
MODULE_DESCRIPTION("NatSemi SCx200 GPIO Pin Driver");
MODULE_LICENSE("GPL");

static int major = 0;		/* default to dynamic major */
module_param(major, int, 0);
MODULE_PARM_DESC(major, "Major device number");

extern void scx200_gpio_dump(unsigned index);

extern ssize_t nsc_gpio_write(struct file *file, const char __user *data,
			      size_t len, loff_t *ppos);

extern ssize_t nsc_gpio_read(struct file *file, char __user *buf,
			     size_t len, loff_t *ppos);

struct nsc_gpio_ops scx200_access = {
	.owner		= THIS_MODULE,
	.gpio_config	= scx200_gpio_configure,
	.gpio_dump	= scx200_gpio_dump,
	.gpio_get	= scx200_gpio_get,
	.gpio_set	= scx200_gpio_set,
	.gpio_set_high	= scx200_gpio_set_high,
	.gpio_set_low	= scx200_gpio_set_low,
	.gpio_change	= scx200_gpio_change,
	.gpio_current	= scx200_gpio_current
};

static int scx200_gpio_open(struct inode *inode, struct file *file)
{
	unsigned m = iminor(inode);
	file->private_data = &scx200_access;

	if (m > 63)
		return -EINVAL;
	return nonseekable_open(inode, file);
}

static int scx200_gpio_release(struct inode *inode, struct file *file)
{
	return 0;
}


static struct file_operations scx200_gpio_fops = {
	.owner   = THIS_MODULE,
	.write   = nsc_gpio_write,
	.read    = nsc_gpio_read,
	.open    = scx200_gpio_open,
	.release = scx200_gpio_release,
};

struct cdev *scx200_devices;
static int num_pins = 32;

static int __init scx200_gpio_init(void)
{
	int rc, i;
	dev_t dev = MKDEV(major, 0);

	if (!scx200_gpio_present()) {
		printk(KERN_ERR NAME ": no SCx200 gpio present\n");
		return -ENODEV;
	}

	/* support dev_dbg() with pdev->dev */
	pdev = platform_device_alloc(DEVNAME, 0);
	if (!pdev)
		return -ENOMEM;

	rc = platform_device_add(pdev);
	if (rc)
		goto undo_malloc;

	if (major)
		rc = register_chrdev_region(dev, num_pins, "scx200_gpio");
	else {
		rc = alloc_chrdev_region(&dev, 0, num_pins, "scx200_gpio");
		major = MAJOR(dev);
	}
	if (rc < 0) {
		dev_err(&pdev->dev, "SCx200 chrdev_region err: %d\n", rc);
		goto undo_platform_device_add;
	}
	scx200_devices = kzalloc(num_pins * sizeof(struct cdev), GFP_KERNEL);
	if (!scx200_devices) {
		rc = -ENOMEM;
		goto undo_chrdev_region;
	}
	for (i = 0; i < num_pins; i++) {
		struct cdev *cdev = &scx200_devices[i];
		cdev_init(cdev, &scx200_gpio_fops);
		cdev->owner = THIS_MODULE;
		rc = cdev_add(cdev, MKDEV(major, i), 1);
		/* tolerate 'minor' errors */
		if (rc)
			dev_err(&pdev->dev, "Error %d on minor %d", rc, i);
	}

	return 0; /* succeed */

undo_chrdev_region:
	unregister_chrdev_region(dev, num_pins);
undo_platform_device_add:
	platform_device_put(pdev);
undo_malloc:
	kfree(pdev);
	return rc;
}

static void __exit scx200_gpio_cleanup(void)
{
	kfree(scx200_devices);
	unregister_chrdev_region(MKDEV(major, 0), num_pins);
	platform_device_put(pdev);
	platform_device_unregister(pdev);
	/* kfree(pdev); */
}

module_init(scx200_gpio_init);
module_exit(scx200_gpio_cleanup);
Commit	Line	Data
62c83cde	1	/* linux/drivers/char/scx200_gpio.c
1da177e4 LT	2
	3	National Semiconductor SCx200 GPIO driver. Allows a user space
	4	process to play with the GPIO pins.
	5
	6	Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com> */
	7
	8	#include <linux/config.h>
979b5ec3	9	#include <linux/device.h>
1da177e4 LT	10	#include <linux/fs.h>
	11	#include <linux/module.h>
	12	#include <linux/errno.h>
	13	#include <linux/kernel.h>
	14	#include <linux/init.h>
979b5ec3	15	#include <linux/platform_device.h>
1da177e4 LT	16	#include <asm/uaccess.h>
	17	#include <asm/io.h>
	18
7d7f2126 JC	19	#include <linux/types.h>
	20	#include <linux/cdev.h>
	21
1da177e4	22	#include <linux/scx200_gpio.h>
fe3a168a	23	#include <linux/nsc_gpio.h>
1da177e4 LT	24
1da177e4 LT	25	#define NAME "scx200_gpio"
979b5ec3 JC	26	#define DEVNAME NAME
	27
	28	static struct platform_device *pdev;
1da177e4 LT	29
	30	MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
	31	MODULE_DESCRIPTION("NatSemi SCx200 GPIO Pin Driver");
	32	MODULE_LICENSE("GPL");
	33
	34	static int major = 0; /* default to dynamic major */
	35	module_param(major, int, 0);
	36	MODULE_PARM_DESC(major, "Major device number");
	37
7d7f2126 JC	38	extern void scx200_gpio_dump(unsigned index);
7d7f2126 JC	39
1a66fdf0 JC	40	extern ssize_t nsc_gpio_write(struct file file, const char __user data,
	41	size_t len, loff_t *ppos);
	42
	43	extern ssize_t nsc_gpio_read(struct file file, char __user buf,
	44	size_t len, loff_t *ppos);
	45
fe3a168a JC	46	struct nsc_gpio_ops scx200_access = {
	47	.owner = THIS_MODULE,
	48	.gpio_config = scx200_gpio_configure,
	49	.gpio_dump = scx200_gpio_dump,
	50	.gpio_get = scx200_gpio_get,
	51	.gpio_set = scx200_gpio_set,
	52	.gpio_set_high = scx200_gpio_set_high,
	53	.gpio_set_low = scx200_gpio_set_low,
	54	.gpio_change = scx200_gpio_change,
	55	.gpio_current = scx200_gpio_current
	56	};
	57
1da177e4 LT	58	static int scx200_gpio_open(struct inode inode, struct file file)
	59	{
	60	unsigned m = iminor(inode);
c3dc8071 JC	61	file->private_data = &scx200_access;
c3dc8071 JC	62
1da177e4 LT	63	if (m > 63)
	64	return -EINVAL;
	65	return nonseekable_open(inode, file);
	66	}
	67
	68	static int scx200_gpio_release(struct inode inode, struct file file)
	69	{
	70	return 0;
	71	}
	72
	73
	74	static struct file_operations scx200_gpio_fops = {
	75	.owner = THIS_MODULE,
1a66fdf0 JC	76	.write = nsc_gpio_write,
1a66fdf0 JC	77	.read = nsc_gpio_read,
1da177e4 LT	78	.open = scx200_gpio_open,
	79	.release = scx200_gpio_release,
	80	};
	81
7d7f2126	82	struct cdev *scx200_devices;
979b5ec3	83	static int num_pins = 32;
7d7f2126	84
1da177e4 LT	85	static int __init scx200_gpio_init(void)
1da177e4 LT	86	{
7d7f2126 JC	87	int rc, i;
7d7f2126 JC	88	dev_t dev = MKDEV(major, 0);
1da177e4	89
1da177e4	90	if (!scx200_gpio_present()) {
7d7f2126	91	printk(KERN_ERR NAME ": no SCx200 gpio present\n");
1da177e4 LT	92	return -ENODEV;
1da177e4 LT	93	}
979b5ec3 JC	94
	95	/* support dev_dbg() with pdev->dev */
	96	pdev = platform_device_alloc(DEVNAME, 0);
	97	if (!pdev)
	98	return -ENOMEM;
	99
	100	rc = platform_device_add(pdev);
	101	if (rc)
	102	goto undo_malloc;
	103
7d7f2126	104	if (major)
979b5ec3	105	rc = register_chrdev_region(dev, num_pins, "scx200_gpio");
7d7f2126	106	else {
979b5ec3	107	rc = alloc_chrdev_region(&dev, 0, num_pins, "scx200_gpio");
7d7f2126	108	major = MAJOR(dev);
1da177e4	109	}
7d7f2126	110	if (rc < 0) {
979b5ec3 JC	111	dev_err(&pdev->dev, "SCx200 chrdev_region err: %d\n", rc);
979b5ec3 JC	112	goto undo_platform_device_add;
7d7f2126	113	}
979b5ec3	114	scx200_devices = kzalloc(num_pins * sizeof(struct cdev), GFP_KERNEL);
7d7f2126 JC	115	if (!scx200_devices) {
7d7f2126 JC	116	rc = -ENOMEM;
979b5ec3	117	goto undo_chrdev_region;
7d7f2126	118	}
979b5ec3	119	for (i = 0; i < num_pins; i++) {
7d7f2126 JC	120	struct cdev *cdev = &scx200_devices[i];
	121	cdev_init(cdev, &scx200_gpio_fops);
	122	cdev->owner = THIS_MODULE;
7d7f2126	123	rc = cdev_add(cdev, MKDEV(major, i), 1);
979b5ec3	124	/* tolerate 'minor' errors */
7d7f2126	125	if (rc)
979b5ec3	126	dev_err(&pdev->dev, "Error %d on minor %d", rc, i);
1da177e4 LT	127	}
1da177e4 LT	128
979b5ec3	129	return 0; /* succeed */
7d7f2126	130
979b5ec3 JC	131	undo_chrdev_region:
	132	unregister_chrdev_region(dev, num_pins);
	133	undo_platform_device_add:
	134	platform_device_put(pdev);
	135	undo_malloc:
	136	kfree(pdev);
7d7f2126	137	return rc;
1da177e4 LT	138	}
	139
	140	static void __exit scx200_gpio_cleanup(void)
	141	{
7d7f2126	142	kfree(scx200_devices);
979b5ec3 JC	143	unregister_chrdev_region(MKDEV(major, 0), num_pins);
	144	platform_device_put(pdev);
	145	platform_device_unregister(pdev);
	146	/* kfree(pdev); */
1da177e4 LT	147	}
	148
	149	module_init(scx200_gpio_init);
	150	module_exit(scx200_gpio_cleanup);