PCI: ibmphp: Turn semaphores into completions or mutexes

The sem_exit variable is conceptually a completion, so it should be called
that.

Similarly, the semOperations semaphore is a simple mutex, and can be
changed into that, respectively.

With both converted, the ibmphp_hpc_initvars() function is no longer used
and can be removed.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/pci/hotplug/ibmphp.h b/drivers/pci/hotplug/ibmphp.h
index b89f850..e90a4eb 100644 (file)
--- a/drivers/pci/hotplug/ibmphp.h
+++ b/drivers/pci/hotplug/ibmphp.h
@@ -378,7 +378,6 @@ int ibmphp_add_pfmem_from_mem(struct resource_node *);
 struct bus_node *ibmphp_find_res_bus(u8);
 void ibmphp_print_test(void);  /* for debugging purposes */
 
-void ibmphp_hpc_initvars(void);
 int ibmphp_hpc_readslot(struct slot *, u8, u8 *);
 int ibmphp_hpc_writeslot(struct slot *, u8);
 void ibmphp_lock_operations(void);

diff --git a/drivers/pci/hotplug/ibmphp_core.c b/drivers/pci/hotplug/ibmphp_core.c
index 08a58e9..1712425 100644 (file)
--- a/drivers/pci/hotplug/ibmphp_core.c
+++ b/drivers/pci/hotplug/ibmphp_core.c
@@ -1277,8 +1277,6 @@ static int __init ibmphp_init(void)
 
        ibmphp_debug = debug;
 
-       ibmphp_hpc_initvars();
-
        for (i = 0; i < 16; i++)
                irqs[i] = 0;
 

diff --git a/drivers/pci/hotplug/ibmphp_hpc.c b/drivers/pci/hotplug/ibmphp_hpc.c
index 752c384..508a62a 100644 (file)
--- a/drivers/pci/hotplug/ibmphp_hpc.c
+++ b/drivers/pci/hotplug/ibmphp_hpc.c
@@ -15,13 +15,13 @@
 
 #include <linux/wait.h>
 #include <linux/time.h>
+#include <linux/completion.h>
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/init.h>
 #include <linux/mutex.h>
 #include <linux/sched.h>
-#include <linux/semaphore.h>
 #include <linux/kthread.h>
 #include "ibmphp.h"
 
@@ -88,10 +88,10 @@ static int to_debug = 0;
 //----------------------------------------------------------------------------
 // global variables
 //----------------------------------------------------------------------------
-static struct mutex sem_hpcaccess;     // lock access to HPC
-static struct semaphore semOperations; // lock all operations and
+static DEFINE_MUTEX(sem_hpcaccess);    // lock access to HPC
+static DEFINE_MUTEX(operations_mutex); // lock all operations and
                                        // access to data structures
-static struct semaphore sem_exit;      // make sure polling thread goes away
+static DECLARE_COMPLETION(exit_complete); // make sure polling thread goes away
 static struct task_struct *ibmphp_poll_thread;
 //----------------------------------------------------------------------------
 // local function prototypes
@@ -110,23 +110,6 @@ static int hpc_wait_ctlr_notworking(int, struct controller *, void __iomem *, u8
 
 
 /*----------------------------------------------------------------------
-* Name:    ibmphp_hpc_initvars
-*
-* Action:  initialize semaphores and variables
-*---------------------------------------------------------------------*/
-void __init ibmphp_hpc_initvars(void)
-{
-       debug("%s - Entry\n", __func__);
-
-       mutex_init(&sem_hpcaccess);
-       sema_init(&semOperations, 1);
-       sema_init(&sem_exit, 0);
-       to_debug = 0;
-
-       debug("%s - Exit\n", __func__);
-}
-
-/*----------------------------------------------------------------------
 * Name:    i2c_ctrl_read
 *
 * Action:  read from HPC over I2C
@@ -780,7 +763,7 @@ void free_hpc_access(void)
 *---------------------------------------------------------------------*/
 void ibmphp_lock_operations(void)
 {
-       down(&semOperations);
+       mutex_lock(&operations_mutex);
        to_debug = 1;
 }
 
@@ -790,7 +773,7 @@ void ibmphp_lock_operations(void)
 void ibmphp_unlock_operations(void)
 {
        debug("%s - Entry\n", __func__);
-       up(&semOperations);
+       mutex_unlock(&operations_mutex);
        to_debug = 0;
        debug("%s - Exit\n", __func__);
 }
@@ -816,7 +799,7 @@ static int poll_hpc(void *data)
 
        while (!kthread_should_stop()) {
                /* try to get the lock to do some kind of hardware access */
-               down(&semOperations);
+               mutex_lock(&operations_mutex);
 
                switch (poll_state) {
                case POLL_LATCH_REGISTER:
@@ -871,13 +854,13 @@ static int poll_hpc(void *data)
                        break;
                case POLL_SLEEP:
                        /* don't sleep with a lock on the hardware */
-                       up(&semOperations);
+                       mutex_unlock(&operations_mutex);
                        msleep(POLL_INTERVAL_SEC * 1000);
 
                        if (kthread_should_stop())
                                goto out_sleep;
 
-                       down(&semOperations);
+                       mutex_lock(&operations_mutex);
 
                        if (poll_count >= POLL_LATCH_CNT) {
                                poll_count = 0;
@@ -887,12 +870,12 @@ static int poll_hpc(void *data)
                        break;
                }
                /* give up the hardware semaphore */
-               up(&semOperations);
+               mutex_unlock(&operations_mutex);
                /* sleep for a short time just for good measure */
 out_sleep:
                msleep(100);
        }
-       up(&sem_exit);
+       complete(&exit_complete);
        debug("%s - Exit\n", __func__);
        return 0;
 }
@@ -1060,9 +1043,9 @@ void __exit ibmphp_hpc_stop_poll_thread(void)
        debug("after locking operations\n");
 
        // wait for poll thread to exit
-       debug("before sem_exit down\n");
-       down(&sem_exit);
-       debug("after sem_exit down\n");
+       debug("before exit_complete down\n");
+       wait_for_completion(&exit_complete);
+       debug("after exit_completion down\n");
 
        // cleanup
        debug("before free_hpc_access\n");
@@ -1070,8 +1053,6 @@ void __exit ibmphp_hpc_stop_poll_thread(void)
        debug("after free_hpc_access\n");
        ibmphp_unlock_operations();
        debug("after unlock operations\n");
-       up(&sem_exit);
-       debug("after sem exit up\n");
 
        debug("%s - Exit\n", __func__);
 }