Staging: comedi: Remove checks for NULL before calling kfree()

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / staging / comedi / proc.c

/*
    module/proc.c
    /proc interface for comedi

    COMEDI - Linux Control and Measurement Device Interface
    Copyright (C) 1998 David A. Schleef <ds@schleef.org>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

/*
	This is some serious bloatware.

	Taken from Dave A.'s PCL-711 driver, 'cuz I thought it
	was cool.
*/

#define __NO_VERSION__
#include "comedidev.h"
#include <linux/proc_fs.h>
/* #include <linux/string.h> */

int comedi_read_procmem(char *buf, char **start, off_t offset, int len,
	int *eof, void *data);

extern comedi_driver *comedi_drivers;

int comedi_read_procmem(char *buf, char **start, off_t offset, int len,
	int *eof, void *data)
{
	int i;
	int devices_q = 0;
	int l = 0;
	comedi_driver *driv;

	l += sprintf(buf + l,
		"comedi version " COMEDI_RELEASE "\n"
		"format string: %s\n",
		"\"%2d: %-20s %-20s %4d\",i,driver_name,board_name,n_subdevices");

	for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
		struct comedi_device_file_info *dev_file_info = comedi_get_device_file_info(i);
		comedi_device *dev;

		if (dev_file_info == NULL)
			continue;
		dev = dev_file_info->device;

		if (dev->attached) {
			devices_q = 1;
			l += sprintf(buf + l, "%2d: %-20s %-20s %4d\n",
				i,
				dev->driver->driver_name,
				dev->board_name, dev->n_subdevices);
		}
	}
	if (!devices_q) {
		l += sprintf(buf + l, "no devices\n");
	}

	for (driv = comedi_drivers; driv; driv = driv->next) {
		l += sprintf(buf + l, "%s:\n", driv->driver_name);
		for (i = 0; i < driv->num_names; i++) {
			l += sprintf(buf + l, " %s\n",
				*(char **)((char *)driv->board_name +
					i * driv->offset));
		}
		if (!driv->num_names) {
			l += sprintf(buf + l, " %s\n", driv->driver_name);
		}
	}

	return l;
}

#ifdef CONFIG_PROC_FS
void comedi_proc_init(void)
{
	struct proc_dir_entry *comedi_proc;

	comedi_proc = create_proc_entry("comedi", S_IFREG | S_IRUGO, 0);
	if (comedi_proc)
		comedi_proc->read_proc = comedi_read_procmem;
}

void comedi_proc_cleanup(void)
{
	remove_proc_entry("comedi", 0);
}
#endif