Commit 979b5ec3 authored by Jim Cromie's avatar Jim Cromie Committed by Linus Torvalds
Browse files

[PATCH] chardev: GPIO for SCx200 & PC-8736x: add platforn_device for use w dev_dbg 



Add a platform-device to scx200_gpio, and use its struct device dev member
(ie: devp) in dev_dbg() once.

There are 2 alternatives here (Im soliciting guidance/commentary):

- use isa_device, if/when its added to the kernel.

- alter scx200.c to EXPORT_GPL its private devp so that both scx200_gpio,
  and the (to be added) nsc_gpio module can use it.  Since the available devp
  is in 'grandparent', this seems like too much 'action at a distance'.

Signed-off-by: default avatarJim Cromie <jim.cromie@gmail.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 7d7f2126

drivers/char/scx200_gpio.c

+36 −17
Original line number Diff line number Diff line
@@ -6,11 +6,13 @@ 
   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>
@@ -20,6 +22,9 @@ 
#include <linux/scx200_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");
@@ -114,56 +119,70 @@ static struct file_operations scx200_gpio_fops = { 
};



struct cdev *scx200_devices;

int num_devs = 32;

static int num_pins = 32;



static int __init scx200_gpio_init(void)

{

	int rc, i;

	dev_t dev = MKDEV(major, 0);



	printk(KERN_DEBUG NAME ": NatSemi SCx200 GPIO Driver\n");



	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_devs, "scx200_gpio");

		rc = register_chrdev_region(dev, num_pins, "scx200_gpio");

	else {

		rc = alloc_chrdev_region(&dev, 0, num_devs, "scx200_gpio");

		rc = alloc_chrdev_region(&dev, 0, num_pins, "scx200_gpio");

		major = MAJOR(dev);

	}

	if (rc < 0) {

		printk(KERN_ERR NAME ": SCx200 chrdev_region: %d\n", rc);

		return rc;

		dev_err(&pdev->dev, "SCx200 chrdev_region err: %d\n", rc);

		goto undo_platform_device_add;

	}

	scx200_devices = kzalloc(num_devs * sizeof(struct cdev), GFP_KERNEL);

	scx200_devices = kzalloc(num_pins * sizeof(struct cdev), GFP_KERNEL);

	if (!scx200_devices) {

		rc = -ENOMEM;

		goto fail_malloc;

		goto undo_chrdev_region;

	}

	for (i = 0; i < num_devs; i++) {

	for (i = 0; i < num_pins; i++) {

		struct cdev *cdev = &scx200_devices[i];

		cdev_init(cdev, &scx200_gpio_fops);

		cdev->owner = THIS_MODULE;

		cdev->ops = &scx200_gpio_fops;

		rc = cdev_add(cdev, MKDEV(major, i), 1);

		/* Fail gracefully if need be */

		/* tolerate 'minor' errors */

		if (rc)

			printk(KERN_ERR NAME "Error %d on minor %d", rc, i);

			dev_err(&pdev->dev, "Error %d on minor %d", rc, i);

	}



	return 0; /* succeed */



fail_malloc:

	unregister_chrdev_region(dev, num_devs);

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_devs);

	unregister_chrdev_region(MKDEV(major, 0), num_pins);

	platform_device_put(pdev);

	platform_device_unregister(pdev);

	/* kfree(pdev); */

}



module_init(scx200_gpio_init);

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