[PATCH 21/30] rapidio: move rio_pw_enable into core code

[Alexandre Bounine]

Make rio_pw_enable() routine available to other RapidIO drivers.

Signed-off-by: Alexandre Bounine <alexandre.boun...@idt.com>
Cc: Matt Porter <mpor...@kernel.crashing.org>
Cc: Aurelien Jacquiot <a-jacqu...@ti.com>
Cc: Andre van Herk <andre.van.h...@prodrive-technologies.com>
Cc: linux-kernel@vger.kernel.org
---
 drivers/rapidio/rio-scan.c |   11 -----------
 drivers/rapidio/rio.c      |   19 +++++++++++++++++++
 include/linux/rio.h        |    2 ++
 include/linux/rio_drv.h    |    1 +
 4 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/drivers/rapidio/rio-scan.c b/drivers/rapidio/rio-scan.c
index f730914..a63a380 100644
--- a/drivers/rapidio/rio-scan.c
+++ b/drivers/rapidio/rio-scan.c
@@ -974,17 +974,6 @@ static void rio_init_em(struct rio_dev *rdev)
 }
 
 /**
- * rio_pw_enable - Enables/disables port-write handling by a master port
- * @port: Master port associated with port-write handling
- * @enable:  1=enable,  0=disable
- */
-static void rio_pw_enable(struct rio_mport *port, int enable)
-{
-       if (port->ops->pwenable)
-               port->ops->pwenable(port, enable);
-}
-
-/**
  * rio_enum_mport- Start enumeration through a master port
  * @mport: Master port to send transactions
  * @flags: Enumeration control flags
diff --git a/drivers/rapidio/rio.c b/drivers/rapidio/rio.c
index 3d268ee..811bea8 100644
--- a/drivers/rapidio/rio.c
+++ b/drivers/rapidio/rio.c
@@ -560,6 +560,24 @@ int rio_release_inb_pwrite(struct rio_dev *rdev)
 EXPORT_SYMBOL_GPL(rio_release_inb_pwrite);
 
 /**
+ * rio_pw_enable - Enables/disables port-write handling by a master port
+ * @port: Master port associated with port-write handling
+ * @enable:  1=enable,  0=disable
+ */
+void rio_pw_enable(struct rio_mport *mport, int enable)
+{
+       if (mport->ops->pwenable) {
+               mutex_lock(&mport->lock);
+
+               if ((enable && ++mport->pwe_refcnt == 1) ||
+                   (!enable && mport->pwe_refcnt && --mport->pwe_refcnt == 0))
+                       mport->ops->pwenable(mport, enable);
+               mutex_unlock(&mport->lock);
+       }
+}
+EXPORT_SYMBOL_GPL(rio_pw_enable);
+
+/**
  * rio_map_inb_region -- Map inbound memory region.
  * @mport: Master port.
  * @local: physical address of memory region to be mapped
@@ -2041,6 +2059,7 @@ int rio_mport_initialize(struct rio_mport *mport)
        mport->host_deviceid = rio_get_hdid(mport->id);
        mport->nscan = NULL;
        mutex_init(&mport->lock);
+       mport->pwe_refcnt = 0;
 
        return 0;
 }
diff --git a/include/linux/rio.h b/include/linux/rio.h
index fc614c5..26eb7b0 100644
--- a/include/linux/rio.h
+++ b/include/linux/rio.h
@@ -266,6 +266,7 @@ enum rio_phy_type {
  * @dma: DMA device associated with mport
  * @nscan: RapidIO network enumeration/discovery operations
  * @state: mport device state
+ * @pwe_refcnt: port-write enable ref counter to track enable/disable requests
  */
 struct rio_mport {
        struct list_head dbells;        /* list of doorbell events */
@@ -296,6 +297,7 @@ struct rio_mport {
 #endif
        struct rio_scan *nscan;
        atomic_t state;
+       unsigned int pwe_refcnt;
 };
 
 static inline int rio_mport_is_running(struct rio_mport *mport)
diff --git a/include/linux/rio_drv.h b/include/linux/rio_drv.h
index 341b3bf..9fb2bcd 100644
--- a/include/linux/rio_drv.h
+++ b/include/linux/rio_drv.h
@@ -375,6 +375,7 @@ extern int rio_request_inb_pwrite(struct rio_dev *,
                        int (*)(struct rio_dev *, union rio_pw_msg*, int));
 extern int rio_release_inb_pwrite(struct rio_dev *);
 extern int rio_inb_pwrite_handler(union rio_pw_msg *pw_msg);
+extern void rio_pw_enable(struct rio_mport *mport, int enable);
 
 /* LDM support */
 int rio_register_driver(struct rio_driver *);
-- 
1.7.8.4