1 files changed, 137 insertions, 58 deletions

diff --git a/drivers/staging/ozwpan/ozevent.c b/drivers/staging/ozwpan/ozevent.c
index 73703d3e96bd..7f66b4f19b01 100644
--- a/drivers/staging/ozwpan/ozevent.c
+++ b/drivers/staging/ozwpan/ozevent.c
@@ -5,29 +5,46 @@
  */
 #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 seperately to avoid the need to
+ * export definition of struct oz_evtdev.
  */
-unsigned long g_evt_mask = 0xffffffff;
+u32 g_evt_mask;
 /*------------------------------------------------------------------------------
  */
 #define OZ_MAX_EVTS	2048	/* Must be power of 2 */
-DEFINE_SPINLOCK(g_eventlock);
-static int g_evt_in;
-static int g_evt_out;
-static int g_missed_events;
-static struct oz_event g_events[OZ_MAX_EVTS];
+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 initally zero so no
+	 * need to reinitialised those.
+	 */
 	oz_trace("Event tracing initialized\n");
-	g_evt_in = g_evt_out = 0;
-	g_missed_events = 0;
+	spin_lock_init(&g_evtdev.lock);
+	atomic_set(&g_evtdev.users, 0);
 }
 /*------------------------------------------------------------------------------
  * Context: process
@@ -43,74 +60,136 @@ void oz_event_log2(u8 evt, u8 ctx1, u16 ctx2, void *ctx3, unsigned ctx4)
 {
 	unsigned long irqstate;
 	int ix;
-	spin_lock_irqsave(&g_eventlock, irqstate);
-	ix = (g_evt_in + 1) & (OZ_MAX_EVTS - 1);
-	if (ix != g_evt_out) {
-		struct oz_event *e = &g_events[g_evt_in];
+	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 = ctx3;
+		e->ctx3 = (__u32)(unsigned long)ctx3;
 		e->ctx4 = ctx4;
-		g_evt_in = ix;
+		g_evtdev.evt_in = ix;
 	} else {
-		g_missed_events++;
+		g_evtdev.missed_events++;
 	}
-	spin_unlock_irqrestore(&g_eventlock, irqstate);
+	spin_unlock_irqrestore(&g_evtdev.lock, irqstate);
 }
 /*------------------------------------------------------------------------------
  * Context: process
  */
-int oz_events_copy(struct oz_evtlist __user *lst)
+static void oz_events_clear(struct oz_evtdev *dev)
 {
-	int first;
-	int ix;
-	struct hdr {
-		int count;
-		int missed;
-	} hdr;
-	ix = g_evt_out;
-	hdr.count = g_evt_in - ix;
-	if (hdr.count < 0)
-		hdr.count += OZ_MAX_EVTS;
-	if (hdr.count > OZ_EVT_LIST_SZ)
-		hdr.count = OZ_EVT_LIST_SZ;
-	hdr.missed = g_missed_events;
-	g_missed_events = 0;
-	if (copy_to_user((void __user *)lst, &hdr, sizeof(hdr)))
-		return -EFAULT;
-	first = OZ_MAX_EVTS - ix;
-	if (first > hdr.count)
-		first = hdr.count;
-	if (first) {
-		int sz = first*sizeof(struct oz_event);
-		void __user *p = (void __user *)lst->evts;
-		if (copy_to_user(p, &g_events[ix], sz))
-			return -EFAULT;
-		if (hdr.count > first) {
-			p = (void __user *)&lst->evts[first];
-			sz = (hdr.count-first)*sizeof(struct oz_event);
-			if (copy_to_user(p, g_events, sz))
-				return -EFAULT;
-		}
+	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);
+}
+#ifdef CONFIG_DEBUG_FS
+/*------------------------------------------------------------------------------
+ * Context: process
+ */
+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;
 	}
-	ix += hdr.count;
-	if (ix >= OZ_MAX_EVTS)
-		ix -= OZ_MAX_EVTS;
-	g_evt_out = ix;
+}
+/*------------------------------------------------------------------------------
+ * Context: process
+ */
+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
  */
-void oz_events_clear(void)
+ssize_t oz_events_read(struct file *filp, char __user *buf, size_t count,
+		loff_t *fpos)
 {
-	unsigned long irqstate;
-	spin_lock_irqsave(&g_eventlock, irqstate);
-	g_evt_in = g_evt_out = 0;
-	g_missed_events = 0;
-	spin_unlock_irqrestore(&g_eventlock, irqstate);
+	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;
 }
-#endif /* WANT_EVENT_TRACE */
+/*------------------------------------------------------------------------------
+ */
+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 */