arch/arm/plat-omap/dsp/taskwatch.c

   1 /*
   2  * This file is part of OMAP DSP driver (DSP Gateway version 3.3.1)
   3  *
   4  * Copyright (C) 2002-2006 Nokia Corporation. All rights reserved.
   5  *
   6  * Contact: Toshihiro Kobayashi <toshihiro.kobayashi@nokia.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * version 2 as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  20  * 02110-1301 USA
  21  *
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/fs.h>
  26 #include <linux/poll.h>
  27 #include <linux/sched.h>
  28 #include <asm/uaccess.h>
  29 #include "dsp_mbcmd.h"
  30 #include "dsp.h"
  31 #include "ioctl.h"
  32
  33 static DECLARE_WAIT_QUEUE_HEAD(read_wait_q);
  34 static unsigned int change_cnt;
  35
  36 void dsp_twch_touch(void)
  37 {
  38         change_cnt++;
  39         wake_up_interruptible(&read_wait_q);
  40 }
  41
  42 /*
  43  * @count: represents the device counts of the user's interst
  44  */
  45 static ssize_t dsp_twch_read(struct file *file, char __user *buf, size_t count,
  46                              loff_t *ppos)
  47 {
  48         long taskstat[TASKDEV_MAX];
  49         int devcount = count / sizeof(long);
  50         int i;
  51
  52         if (dsp_cfgstat_get_stat() != CFGSTAT_READY) {
  53                 printk(KERN_ERR "omapdsp: dsp has not been configured.\n");
  54                 return -EINVAL;
  55         }
  56
  57         if (change_cnt == 0) {
  58                 long current_state;
  59                 DECLARE_WAITQUEUE(wait, current);
  60
  61                 add_wait_queue(&read_wait_q, &wait);
  62                 current_state = current->state;
  63                 set_current_state(TASK_INTERRUPTIBLE);
  64                 if (change_cnt == 0)    /* last check */
  65                         schedule();
  66                 set_current_state(current_state);
  67                 remove_wait_queue(&read_wait_q, &wait);
  68
  69                 /* unconfigured while waiting ;-( */
  70                 if (dsp_cfgstat_get_stat() != CFGSTAT_READY)
  71                         return -EINVAL;
  72         }
  73
  74         if (devcount > TASKDEV_MAX)
  75                 devcount = TASKDEV_MAX;
  76
  77         count = devcount * sizeof(long);
  78         change_cnt = 0;
  79         for (i = 0; i < devcount; i++) {
  80                 /*
  81                  * once the device state is read, the 'STALE' bit will be set
  82                  * so that the Dynamic Loader can distinguish the new request
  83                  * from the old one.
  84                  */
  85                 taskstat[i] = taskdev_state_stale(i);
  86         }
  87
  88         if (copy_to_user(buf, taskstat, count))
  89                 return -EFAULT;
  90
  91         return count;
  92 }
  93
  94 static unsigned int dsp_twch_poll(struct file *file, poll_table *wait)
  95 {
  96         unsigned int mask = 0;
  97
  98         poll_wait(file, &read_wait_q, wait);
  99         if (change_cnt)
 100                 mask |= POLLIN | POLLRDNORM;
 101
 102         return mask;
 103 }
 104
 105 static int dsp_twch_ioctl(struct inode *inode, struct file *file,
 106                           unsigned int cmd, unsigned long arg)
 107 {
 108         int ret;
 109
 110         switch (cmd) {
 111         case TWCH_IOCTL_MKDEV:
 112                 {
 113                         char name[TNM_LEN];
 114                         if (copy_from_user(name, (void __user *)arg, TNM_LEN))
 115                                 return -EFAULT;
 116                         name[TNM_LEN-1] = '\0';
 117                         ret = dsp_mkdev(name);
 118                         break;
 119                 }
 120
 121         case TWCH_IOCTL_RMDEV:
 122                 {
 123                         char name[TNM_LEN];
 124                         if (copy_from_user(name, (void __user *)arg, TNM_LEN))
 125                                 return -EFAULT;
 126                         name[TNM_LEN-1] = '\0';
 127                         ret = dsp_rmdev(name);
 128                         break;
 129                 }
 130
 131         case TWCH_IOCTL_TADD:
 132                 {
 133                         struct omap_dsp_taddinfo ti;
 134                         if (copy_from_user(&ti, (void __user *)arg, sizeof(ti)))
 135                                 return -EFAULT;
 136                         ret = dsp_tadd_minor(ti.minor, ti.taskadr);
 137                         break;
 138                 }
 139
 140         case TWCH_IOCTL_TDEL:
 141                 ret = dsp_tdel_minor(arg);
 142                 break;
 143
 144         case TWCH_IOCTL_TKILL:
 145                 ret = dsp_tkill_minor(arg);
 146                 break;
 147
 148         default:
 149                 return -ENOIOCTLCMD;
 150         }
 151
 152         return ret;
 153 }
 154
 155 struct file_operations dsp_twch_fops = {
 156         .owner = THIS_MODULE,
 157         .read  = dsp_twch_read,
 158         .poll  = dsp_twch_poll,
 159         .ioctl = dsp_twch_ioctl,
 160 };
 161
 162 void dsp_twch_start(void)
 163 {
 164         change_cnt = 1;         /* first read will not wait */
 165 }
 166
 167 void dsp_twch_stop(void)
 168 {
 169         wake_up_interruptible(&read_wait_q);
 170 }