trv_proc.c

mpc8xx driver(led), based on tqm8

/***********************************************************************
 *
 * (C) Copyright 2000
 * Jean-Jacques Germond, Fr閐閞ic Soulier, Christian Batt; Alcatel
 * C/O [e-mail]
 *
 * All rights reserved.
 *
 * This code is free software; you can redistribute it and/or
 * modify it under the terms of the GNU *Library* General Public License
 * as published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This code 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
 * *Library* General Public License for more details.
 *
 * You should have received a copy of the GNU *Library* General Public
 * License along with this program (see file COPYING.LIB); if not,
 * write to the Free Software Foundation, Inc., 675 Mass Ave,
 * Cambridge, MA 02139, USA.
 *
 ***********************************************************************/

/* The "trivial module" /proc routines  (see AR pg: 74) */
/*  This should be a module of its own */

#define __NO_VERSION__ 


#include "trv_def.h"

#ifndef CONFIG_PROC_FS
#  define CONFIG_PROC_FS     /* This is for proc_fs.h */
#endif

#include "linux/proc_fs.h"

/* A strucure to control writing in the PAGE_SIZE restricted buffer */
typedef struct {
  char* ptst;
  int   nbchars;
} TrvProc;

    static void
trv_proc_put(char carac, TrvProc* tp)
     /* Put one char in the buffer if there is still room into */
     /* Notice the the final end-of-string will be deposited */
{
  tp->ptst[tp->nbchars] = carac;
  if (tp->nbchars < (PAGE_SIZE - 2)) {
    tp->nbchars++;
  }
}

    static void
trv_proc_puthex8(unsigned long val, TrvProc* tp)
{ 
  int i;

  for (i = 0; i < 8; i++) {
    unsigned int aux = (val >> 28) & 0x0f;
    val <<= 4;
    trv_proc_put((aux < 10) ? (aux + '0') : (aux + 'A' - 10), tp);
  }
}

   static void
trv_proc_str(char* str, TrvProc* tp)
{
  while (*str != '\0') trv_proc_put(*str++, tp);
}

   static void
trv_proc_soent(int val, TrvProc* tp)
{
  if ( val >= 10) {
    trv_proc_soent(val/10, tp);
  }
  trv_proc_put( (val % 10) + '0', tp);
}


     int
trv_edit_mem(char* buf, char **start, off_t offset, int len, int unused)
     /* Edit the Trivial device info */
{
  int      dev_nbr;            /* Device number */
  int      i;                  /* Work */
  TrvProc  trvProcObj;         /* Want this code to be reentrant */
  TrvProc* tp = &trvProcObj;   /* ....   */
  char*    ptld;               /* Work load pointer */

  /* Init the write control structure */
  tp->ptst    = buf;   
  tp->nbchars = 0;

  /* Loop to edit all the devices */
  for ( dev_nbr = 0; dev_nbr < trv_nr_devs; dev_nbr++) {
    Trv_Dev *dev = trv_devices + dev_nbr;

    /* The device number */
    trv_proc_str("trv", tp);
    trv_proc_soent(dev_nbr, tp);

    /* The descriptor addr */
    trv_proc_str("  Device_addr = 0x", tp);
    trv_proc_puthex8((unsigned long)dev, tp);

    /* The buffer address and nb_chars available */
    ptld = dev->buffer;
    trv_proc_str(" Data_addr = 0x", tp);
    trv_proc_puthex8((unsigned long)dev->buffer, tp);
    trv_proc_str(" nb_chars= ", tp);
    trv_proc_soent(dev->nbchars, tp);

    /* Edit the device's content */
    if (ptld) {
      char aux;

      if (dev->nbchars != 0) {
	for (i = 0; ((i < dev->nbchars) && (i < 200)); i++) {
	  if ( (i % 72) == 0 ) trv_proc_str("\n", tp);  /* Give a newline */
	  aux = *ptld++;
	  /* make it readable */
	  if ((aux < ' ') || (aux > '~')) aux = '.';
	  trv_proc_put(aux, tp);
	}
      } else {
	trv_proc_str("\n--- EMPTY DEVICE ---", tp);
      }
    }
    trv_proc_str("\n", tp);  /* Give a newline */
  }

  /* terminate the string and return */
  trv_proc_put('\0', tp);
  return tp->nbchars - 1;  /* Do not count the trailing zero */
}


static struct proc_dir_entry trv_proc_entry = {
        0,                 /* low_ino: the inode -- dynamic */
        6, "trvmem",       /* len of name and name */
        S_IFREG | S_IRUGO, /* mode */
        1, 0, 0,           /* nlinks, owner, group */
        0, NULL,           /* size - unused; operations -- use default */
        &trv_edit_mem,     /* function used to read data */
        /* nothing more */
};


   void
trv_proc_register(void)
     /* Register the trivial device in /proc */
{
  proc_register(&proc_root, &trv_proc_entry);
}

    void
trv_proc_unregister(void)
{
  proc_unregister(&proc_root, trv_proc_entry.low_ino);
}