patch-2.0.35 linux/drivers/block/paride/pseudo.h

• Lines: 146
• Date: Mon Jul 13 13:47:28 1998
• Orig file: v2.0.34/linux/drivers/block/paride/pseudo.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.0.34/linux/drivers/block/paride/pseudo.h linux/drivers/block/paride/pseudo.h
@@ -0,0 +1,145 @@
+/* 
+        pseudo.h    (c) 1997-8  Grant R. Guenther <grant@torque.net>
+                                Under the terms of the GNU public license.
+
+	This is the "pseudo-interrupt" logic for parallel port drivers.
+
+        This module is #included into each driver.  It makes one
+        function available:
+
+		ps_set_intr( void (*continuation)(void),
+			     int  (*ready)(void),
+			     int timeout,
+			     int nice )
+
+	Which will arrange for ready() to be evaluated frequently and
+	when either it returns true, or timeout jiffies have passed,
+	continuation() will be invoked.
+
+	If nice is true, the test will done approximately once a
+	jiffy.  If nice is 0, the test will also be done whenever
+	the scheduler runs (by adding it to a task queue).
+
+*/
+
+/* Changes:
+
+	1.01	1998.05.03	Switched from cli()/sti() to spinlocks
+
+*/
+	
+#define PS_VERSION	"1.01"
+
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/tqueue.h>
+
+static void ps_timer_int( unsigned long data);
+static void ps_tq_int( void *data);
+
+static int ps_use_tq = 1;
+static void (* ps_continuation)(void);
+static int (* ps_ready)(void);
+static int ps_then;
+static int ps_timeout;
+static int ps_timer_active = 0;
+static int ps_tq_active = 0;
+
+/* static spinlock_t ps_spinlock = SPIN_LOCK_UNLOCKED; */
+
+static struct timer_list ps_timer = {0,0,0,0,ps_timer_int};
+static struct tq_struct ps_tq = {0,0,ps_tq_int,NULL};
+
+static void ps_set_intr( void (*continuation)(void), 
+			 int (*ready)(void),
+			 int timeout, int nice )
+
+{       long	flags;
+
+	spin_lock_irqsave(&ps_spinlock,flags);
+
+	ps_continuation = continuation;
+	ps_ready = ready;
+        ps_then = jiffies;
+	ps_timeout = jiffies + timeout;
+	ps_use_tq = !nice;
+
+        if (ps_use_tq && !ps_tq_active) {
+#ifdef HAVE_DISABLE_HLT
+                disable_hlt();
+#endif
+		ps_tq_active = 1;
+                queue_task(&ps_tq,&tq_scheduler);
+	}
+
+        if (!ps_timer_active) {
+		ps_timer_active = 1;
+                ps_timer.expires = jiffies;
+                add_timer(&ps_timer);
+        }
+
+	spin_unlock_irqrestore(&ps_spinlock,flags);
+}
+
+static void ps_tq_int( void *data )
+
+{       void (*con)(void);
+	long flags;
+
+	spin_lock_irqsave(&ps_spinlock,flags);
+
+        con = ps_continuation;
+
+#ifdef HAVE_DISABLE_HLT
+        enable_hlt();
+#endif
+
+        ps_tq_active = 0;
+
+        if (!con) {
+		spin_unlock_irqrestore(&ps_spinlock,flags);
+		return;
+	}
+        if (!ps_ready || ps_ready() || (jiffies >= ps_timeout)) {
+                ps_continuation = NULL;
+        	spin_unlock_irqrestore(&ps_spinlock,flags);
+                con();
+                return;
+                }
+
+#ifdef HAVE_DISABLE_HLT
+        disable_hlt();
+#endif
+
+        ps_tq_active = 1;
+	queue_task(&ps_tq,&tq_scheduler);
+        spin_unlock_irqrestore(&ps_spinlock,flags);
+}
+
+static void ps_timer_int( unsigned long data)
+
+{       void (*con)(void);
+	long	flags;
+
+	spin_lock_irqsave(&ps_spinlock,flags);
+
+	con = ps_continuation;
+	ps_timer_active = 0;
+	if (!con) {
+	        spin_unlock_irqrestore(&ps_spinlock,flags);
+		return;
+	}
+        if (!ps_ready || ps_ready() || (jiffies >= ps_timeout)) {
+                ps_continuation = NULL;
+	        spin_unlock_irqrestore(&ps_spinlock,flags);
+                con();
+		return;
+		}
+	ps_timer_active = 1;
+        ps_timer.expires = jiffies;
+        add_timer(&ps_timer);
+        spin_unlock_irqrestore(&ps_spinlock,flags);
+}
+
+/* end of pseudo.h */
+