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/* -----------------------------------------------------------------------------
* Copyright (c) 2011 Ozmo Inc
* Released under the GNU General Public License Version 2 (GPLv2).
* -----------------------------------------------------------------------------
*/
#include "ozconfig.h"
#ifdef WANT_EVENT_TRACE
#include <linux/module.h>
#include <linux/debugfs.h>
#include <linux/jiffies.h>
#include <linux/uaccess.h>
#include "oztrace.h"
#include "ozevent.h"
#include "ozappif.h"
/*------------------------------------------------------------------------------
* Although the event mask is logically part of the oz_evtdev structure, it is
* needed outside of this file so define it separately to avoid the need to
* export definition of struct oz_evtdev.
*/
u32 g_evt_mask;
/*------------------------------------------------------------------------------
*/
#define OZ_MAX_EVTS 2048 /* Must be power of 2 */
struct oz_evtdev {
struct dentry *root_dir;
int evt_in;
int evt_out;
int missed_events;
int present;
atomic_t users;
spinlock_t lock;
struct oz_event evts[OZ_MAX_EVTS];
};
static struct oz_evtdev g_evtdev;
/*------------------------------------------------------------------------------
* Context: process
*/
void oz_event_init(void)
{
/* Because g_evtdev is static external all fields initially zero so no
* need to reinitialized those.
*/
oz_trace("Event tracing initialized\n");
spin_lock_init(&g_evtdev.lock);
atomic_set(&g_evtdev.users, 0);
}
/*------------------------------------------------------------------------------
* Context: process
*/
void oz_event_term(void)
{
oz_trace("Event tracing terminated\n");
}
/*------------------------------------------------------------------------------
* Context: any
*/
void oz_event_log2(u8 evt, u8 ctx1, u16 ctx2, void *ctx3, unsigned ctx4)
{
unsigned long irqstate;
int ix;
spin_lock_irqsave(&g_evtdev.lock, irqstate);
ix = (g_evtdev.evt_in + 1) & (OZ_MAX_EVTS - 1);
if (ix != g_evtdev.evt_out) {
struct oz_event *e = &g_evtdev.evts[g_evtdev.evt_in];
e->jiffies = jiffies;
e->evt = evt;
e->ctx1 = ctx1;
e->ctx2 = ctx2;
e->ctx3 = (__u32)(unsigned long)ctx3;
e->ctx4 = ctx4;
g_evtdev.evt_in = ix;
} else {
g_evtdev.missed_events++;
}
spin_unlock_irqrestore(&g_evtdev.lock, irqstate);
}
/*------------------------------------------------------------------------------
* Context: process
*/
#ifdef CONFIG_DEBUG_FS
static void oz_events_clear(struct oz_evtdev *dev)
{
unsigned long irqstate;
oz_trace("Clearing events\n");
spin_lock_irqsave(&dev->lock, irqstate);
dev->evt_in = dev->evt_out = 0;
dev->missed_events = 0;
spin_unlock_irqrestore(&dev->lock, irqstate);
}
/*------------------------------------------------------------------------------
* Context: process
*/
static int oz_events_open(struct inode *inode, struct file *filp)
{
oz_trace("oz_evt_open()\n");
oz_trace("Open flags: 0x%x\n", filp->f_flags);
if (atomic_add_return(1, &g_evtdev.users) == 1) {
oz_events_clear(&g_evtdev);
return nonseekable_open(inode, filp);
} else {
atomic_dec(&g_evtdev.users);
return -EBUSY;
}
}
/*------------------------------------------------------------------------------
* Context: process
*/
static int oz_events_release(struct inode *inode, struct file *filp)
{
oz_events_clear(&g_evtdev);
atomic_dec(&g_evtdev.users);
g_evt_mask = 0;
oz_trace("oz_evt_release()\n");
return 0;
}
/*------------------------------------------------------------------------------
* Context: process
*/
static ssize_t oz_events_read(struct file *filp, char __user *buf, size_t count,
loff_t *fpos)
{
struct oz_evtdev *dev = &g_evtdev;
int rc = 0;
int nb_evts = count / sizeof(struct oz_event);
int n;
int sz;
n = dev->evt_in - dev->evt_out;
if (n < 0)
n += OZ_MAX_EVTS;
if (nb_evts > n)
nb_evts = n;
if (nb_evts == 0)
goto out;
n = OZ_MAX_EVTS - dev->evt_out;
if (n > nb_evts)
n = nb_evts;
sz = n * sizeof(struct oz_event);
if (copy_to_user(buf, &dev->evts[dev->evt_out], sz)) {
rc = -EFAULT;
goto out;
}
if (n == nb_evts)
goto out2;
n = nb_evts - n;
if (copy_to_user(buf + sz, dev->evts, n * sizeof(struct oz_event))) {
rc = -EFAULT;
goto out;
}
out2:
dev->evt_out = (dev->evt_out + nb_evts) & (OZ_MAX_EVTS - 1);
rc = nb_evts * sizeof(struct oz_event);
out:
return rc;
}
/*------------------------------------------------------------------------------
*/
static const struct file_operations oz_events_fops = {
.owner = THIS_MODULE,
.open = oz_events_open,
.release = oz_events_release,
.read = oz_events_read,
};
/*------------------------------------------------------------------------------
* Context: process
*/
void oz_debugfs_init(void)
{
struct dentry *parent;
parent = debugfs_create_dir("ozwpan", NULL);
if (parent == NULL) {
oz_trace("Failed to create debugfs directory ozmo\n");
return;
} else {
g_evtdev.root_dir = parent;
if (debugfs_create_file("events", S_IRUSR, parent, NULL,
&oz_events_fops) == NULL)
oz_trace("Failed to create file ozmo/events\n");
if (debugfs_create_x32("event_mask", S_IRUSR | S_IWUSR, parent,
&g_evt_mask) == NULL)
oz_trace("Failed to create file ozmo/event_mask\n");
}
}
/*------------------------------------------------------------------------------
* Context: process
*/
void oz_debugfs_remove(void)
{
debugfs_remove_recursive(g_evtdev.root_dir);
}
#endif /* CONFIG_DEBUG_FS */
#endif /* WANT_EVENT_TRACE */
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