Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / block / paride / pseudo.h

diff --git a/kernel/drivers/block/paride/pseudo.h b/kernel/drivers/block/paride/pseudo.h
new file mode 100644 (file)
index 0000000..bc37032
--- /dev/null
+++ b/kernel/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(struct work_struct *work);
+
+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_DELAYED_WORK(ps_tq, ps_tq_int);
+
+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_delayed_work(&ps_tq, 0);
+               else
+                       schedule_delayed_work(&ps_tq, ps_nice-1);
+       }
+       spin_unlock_irqrestore(&ps_spinlock,flags);
+}
+
+static void ps_tq_int(struct work_struct *work)
+{
+       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_delayed_work(&ps_tq, 0);
+       else
+               schedule_delayed_work(&ps_tq, ps_nice-1);
+       spin_unlock_irqrestore(&ps_spinlock,flags);
+}
+
+/* end of pseudo.h */
+