1 files changed, 102 insertions, 0 deletions

diff --git a/drivers/block/paride/pseudo.h b/drivers/block/paride/pseudo.h
new file mode 100644
index 000000000000..932342d7a8eb
--- /dev/null
+++ b/drivers/block/paride/pseudo.h
@@ -0,0 +1,102 @@
+/* 
+        pseudo.h    (c) 1997-8  Grant R. Guenther <grant@torque.net>
+                                Under the terms of the GNU General 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 1, 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).  If
+        nice is greater than 1, the test will be done once every
+        (nice-1) jiffies. 
+
+*/
+
+/* Changes:
+
+        1.01    1998.05.03      Switched from cli()/sti() to spinlocks
+        1.02    1998.12.14      Added support for nice > 1
+*/
+        
+#define PS_VERSION      "1.02"
+
+#include <linux/sched.h>
+#include <linux/workqueue.h>
+
+static void ps_tq_int( void *data);
+
+static void (* ps_continuation)(void);
+static int (* ps_ready)(void);
+static unsigned long ps_timeout;
+static int ps_tq_active = 0;
+static int ps_nice = 0;
+
+static DEFINE_SPINLOCK(ps_spinlock __attribute__((unused)));
+
+static DECLARE_WORK(ps_tq, ps_tq_int, NULL);
+
+static void ps_set_intr(void (*continuation)(void), 
+                        int (*ready)(void),
+                        int timeout, int nice)
+{
+        unsigned long   flags;
+
+        spin_lock_irqsave(&ps_spinlock,flags);
+
+        ps_continuation = continuation;
+        ps_ready = ready;
+        ps_timeout = jiffies + timeout;
+        ps_nice = nice;
+
+        if (!ps_tq_active) {
+                ps_tq_active = 1;
+                if (!ps_nice)
+                        schedule_work(&ps_tq);
+                else
+                        schedule_delayed_work(&ps_tq, ps_nice-1);
+        }
+        spin_unlock_irqrestore(&ps_spinlock,flags);
+}
+
+static void ps_tq_int(void *data)
+{
+        void (*con)(void);
+        unsigned long flags;
+
+        spin_lock_irqsave(&ps_spinlock,flags);
+
+        con = ps_continuation;
+        ps_tq_active = 0;
+
+        if (!con) {
+                spin_unlock_irqrestore(&ps_spinlock,flags);
+                return;
+        }
+        if (!ps_ready || ps_ready() || time_after_eq(jiffies, ps_timeout)) {
+                ps_continuation = NULL;
+                spin_unlock_irqrestore(&ps_spinlock,flags);
+                con();
+                return;
+        }
+        ps_tq_active = 1;
+        if (!ps_nice)
+                schedule_work(&ps_tq);
+        else
+                schedule_delayed_work(&ps_tq, ps_nice-1);
+        spin_unlock_irqrestore(&ps_spinlock,flags);
+}
+
+/* end of pseudo.h */
+