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Release 4.11 drivers/char/scx200_gpio.c

Directory: drivers/char
/* 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/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 <linux/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 DRVNAME "scx200_gpio"


static struct platform_device *pdev;

MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
MODULE_DESCRIPTION("NatSemi/AMD 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");


#define MAX_PINS 32		
/* 64 later, when known ok */


struct nsc_gpio_ops scx200_gpio_ops = {
	.owner		= THIS_MODULE,
	.gpio_config	= scx200_gpio_configure,
	.gpio_dump	= nsc_gpio_dump,
	.gpio_get	= scx200_gpio_get,
	.gpio_set	= scx200_gpio_set,
	.gpio_change	= scx200_gpio_change,
	.gpio_current	= scx200_gpio_current
};

EXPORT_SYMBOL_GPL(scx200_gpio_ops);


static int scx200_gpio_open(struct inode *inode, struct file *file) { unsigned m = iminor(inode); file->private_data = &scx200_gpio_ops; if (m >= MAX_PINS) return -EINVAL; return nonseekable_open(inode, file); }

Contributors

PersonTokensPropCommitsCommitProp
Christer Weinigel3367.35%116.67%
Jim Cromie918.37%350.00%
Linus Torvalds612.24%116.67%
Al Viro12.04%116.67%
Total49100.00%6100.00%


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

Contributors

PersonTokensPropCommitsCommitProp
Christer Weinigel19100.00%1100.00%
Total19100.00%1100.00%

static const struct file_operations scx200_gpio_fileops = { .owner = THIS_MODULE, .write = nsc_gpio_write, .read = nsc_gpio_read, .open = scx200_gpio_open, .release = scx200_gpio_release, .llseek = no_llseek, }; static struct cdev scx200_gpio_cdev; /* use 1 cdev for all pins */
static int __init scx200_gpio_init(void) { int rc; dev_t devid; if (!scx200_gpio_present()) { printk(KERN_ERR DRVNAME ": no SCx200 gpio present\n"); return -ENODEV; } /* support dev_dbg() with pdev->dev */ pdev = platform_device_alloc(DRVNAME, 0); if (!pdev) return -ENOMEM; rc = platform_device_add(pdev); if (rc) goto undo_malloc; /* nsc_gpio uses dev_dbg(), so needs this */ scx200_gpio_ops.dev = &pdev->dev; if (major) { devid = MKDEV(major, 0); rc = register_chrdev_region(devid, MAX_PINS, "scx200_gpio"); } else { rc = alloc_chrdev_region(&devid, 0, MAX_PINS, "scx200_gpio"); major = MAJOR(devid); } if (rc < 0) { dev_err(&pdev->dev, "SCx200 chrdev_region err: %d\n", rc); goto undo_platform_device_add; } cdev_init(&scx200_gpio_cdev, &scx200_gpio_fileops); cdev_add(&scx200_gpio_cdev, devid, MAX_PINS); return 0; /* succeed */ undo_platform_device_add: platform_device_del(pdev); undo_malloc: platform_device_put(pdev); return rc; }

Contributors

PersonTokensPropCommitsCommitProp
Jim Cromie14074.07%675.00%
Christer Weinigel4724.87%112.50%
Ingo Molnar21.06%112.50%
Total189100.00%8100.00%


static void __exit scx200_gpio_cleanup(void) { cdev_del(&scx200_gpio_cdev); /* cdev_put(&scx200_gpio_cdev); */ unregister_chrdev_region(MKDEV(major, 0), MAX_PINS); platform_device_unregister(pdev); }

Contributors

PersonTokensPropCommitsCommitProp
Jim Cromie1957.58%480.00%
Christer Weinigel1442.42%120.00%
Total33100.00%5100.00%

module_init(scx200_gpio_init); module_exit(scx200_gpio_cleanup);

Overall Contributors

PersonTokensPropCommitsCommitProp
Jim Cromie25151.97%1254.55%
Christer Weinigel20843.06%14.55%
Linus Torvalds71.45%29.09%
Arnd Bergmann51.04%14.55%
Andrew Morton40.83%14.55%
Arnaldo Carvalho de Melo30.62%14.55%
Ingo Molnar20.41%14.55%
Arjan van de Ven10.21%14.55%
Chris Boot10.21%14.55%
Al Viro10.21%14.55%
Total483100.00%22100.00%
Directory: drivers/char
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