s390/cio: wait_cons_dev don't use static variable

wait_cons_dev is used to busy wait for an interrupt on the console
ccw device. Stop using the static console_subchannel and add a
parameter to this function to specify on which ccw device/subchannel
we have to do the polling.

While at it rename the function to ccw_device_wait_idle and
move it to device.c

Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

7 files changed, 32 insertions, 25 deletions

diff --git a/arch/s390/include/asm/ccwdev.h b/arch/s390/include/asm/ccwdev.h
index e6061617a50b..cb56fb6cff7e 100644
--- a/arch/s390/include/asm/ccwdev.h
+++ b/arch/s390/include/asm/ccwdev.h
@@ -220,6 +220,7 @@ extern void ccw_device_get_id(struct ccw_device *, struct ccw_dev_id *);
 #define to_ccwdrv(n) container_of(n, struct ccw_driver, driver)
 
 extern struct ccw_device *ccw_device_probe_console(void);
+extern void ccw_device_wait_idle(struct ccw_device *);
 extern int ccw_device_force_console(void);
 
 int ccw_device_siosl(struct ccw_device *);
diff --git a/arch/s390/include/asm/cio.h b/arch/s390/include/asm/cio.h
index ad2b924167d7..ffb898961c8d 100644
--- a/arch/s390/include/asm/cio.h
+++ b/arch/s390/include/asm/cio.h
@@ -296,8 +296,6 @@ static inline int ccw_dev_id_is_equal(struct ccw_dev_id *dev_id1,
         return 0;
 }
 
-extern void wait_cons_dev(void);
-
 extern void css_schedule_reprobe(void);
 
 extern void reipl_ccw_dev(struct ccw_dev_id *id);
diff --git a/drivers/s390/char/con3215.c b/drivers/s390/char/con3215.c
index 7b00fa634d40..0d79eec799f1 100644
--- a/drivers/s390/char/con3215.c
+++ b/drivers/s390/char/con3215.c
@@ -502,7 +502,7 @@ static void raw3215_make_room(struct raw3215_info *raw, unsigned int length)
                 raw3215_try_io(raw);
                 raw->flags &= ~RAW3215_FLUSHING;
 #ifdef CONFIG_TN3215_CONSOLE
-                wait_cons_dev();
+                ccw_device_wait_idle(raw->cdev);
 #endif
                 /* Enough room freed up ? */
                 if (RAW3215_BUFFER_SIZE - raw->count >= length)
diff --git a/drivers/s390/char/raw3270.c b/drivers/s390/char/raw3270.c
index 4c9030a5b9f2..383d6432a1a8 100644
--- a/drivers/s390/char/raw3270.c
+++ b/drivers/s390/char/raw3270.c
@@ -796,7 +796,7 @@ struct raw3270 __init *raw3270_setup_console(struct ccw_device *cdev)
         do {
                 __raw3270_reset_device(rp);
                 while (!raw3270_state_final(rp)) {
-                        wait_cons_dev();
+                        ccw_device_wait_idle(rp->cdev);
                         barrier();
                 }
         } while (rp->state != RAW3270_STATE_READY);
@@ -810,7 +810,7 @@ raw3270_wait_cons_dev(struct raw3270 *rp)
         unsigned long flags;
 
         spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
-        wait_cons_dev();
+        ccw_device_wait_idle(rp->cdev);
         spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
 }
 
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
index 986ef6a92a41..2c1d53fb2fab 100644
--- a/drivers/s390/cio/cio.c
+++ b/drivers/s390/cio/cio.c
@@ -656,9 +656,9 @@ static int console_subchannel_in_use;
 
 /*
  * Use cio_tsch to update the subchannel status and call the interrupt handler
- * if status had been pending. Called with the console_subchannel lock.
+ * if status had been pending. Called with the subchannel's lock held.
  */
-static void cio_tsch(struct subchannel *sch)
+void cio_tsch(struct subchannel *sch)
 {
         struct irb *irb;
         int irq_context;
@@ -690,22 +690,6 @@ void *cio_get_console_priv(void)
         return &console_priv;
 }
 
-/*
- * busy wait for the next interrupt on the console
- */
-void wait_cons_dev(void)
-{
-        if (!console_subchannel_in_use)
-                return;
-
-        while (1) {
-                cio_tsch(&console_subchannel);
-                if (console_subchannel.schib.scsw.cmd.actl == 0)
-                        break;
-                udelay_simple(100);
-        }
-}
-
 static int
 cio_test_for_console(struct subchannel_id schid, void *data)
 {
diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
index 4a1ff5c2eb88..3b97c8bb30e5 100644
--- a/drivers/s390/cio/cio.h
+++ b/drivers/s390/cio/cio.h
@@ -133,6 +133,7 @@ extern int cio_is_console(struct subchannel_id);
 extern struct subchannel *cio_get_console_subchannel(void);
 extern spinlock_t * cio_get_console_lock(void);
 extern void *cio_get_console_priv(void);
+extern void cio_tsch(struct subchannel *sch);
 #else
 #define cio_is_console(schid) 0
 #define cio_get_console_subchannel() NULL
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index c6767f5a58b2..2e1e9086e916 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -19,6 +19,7 @@
 #include <linux/list.h>
 #include <linux/device.h>
 #include <linux/workqueue.h>
+#include <linux/delay.h>
 #include <linux/timer.h>
 #include <linux/kernel_stat.h>
 
@@ -1612,13 +1613,15 @@ static int ccw_device_console_enable(struct ccw_device *cdev,
         /* Now wait for the async. recognition to come to an end. */
         spin_lock_irq(cdev->ccwlock);
         while (!dev_fsm_final_state(cdev))
-                wait_cons_dev();
+                ccw_device_wait_idle(cdev);
+
         rc = -EIO;
         if (cdev->private->state != DEV_STATE_OFFLINE)
                 goto out_unlock;
         ccw_device_online(cdev);
         while (!dev_fsm_final_state(cdev))
-                wait_cons_dev();
+                ccw_device_wait_idle(cdev);
+
         if (cdev->private->state != DEV_STATE_ONLINE)
                 goto out_unlock;
         rc = 0;
@@ -1655,6 +1658,26 @@ ccw_device_probe_console(void)
         return &console_cdev;
 }
 
+/**
+ * ccw_device_wait_idle() - busy wait for device to become idle
+ * @cdev: ccw device
+ *
+ * Poll until activity control is zero, that is, no function or data
+ * transfer is pending/active.
+ * Called with device lock being held.
+ */
+void ccw_device_wait_idle(struct ccw_device *cdev)
+{
+        struct subchannel *sch = to_subchannel(cdev->dev.parent);
+
+        while (1) {
+                cio_tsch(sch);
+                if (sch->schib.scsw.cmd.actl == 0)
+                        break;
+                udelay_simple(100);
+        }
+}
+
 static int ccw_device_pm_restore(struct device *dev);
 
 int ccw_device_force_console(void)