ACPI: replace spin_lock_irq with mutex for ec poll mode

http://bugzilla.kernel.org/show_bug.cgi?id=5764

Signed-off-by: Luming Yu <luming.yu@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 29 insertions, 22 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index eee0864ba300..d2638209c604 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -116,7 +116,7 @@ union acpi_ec {
                 struct acpi_generic_address command_addr;
                 struct acpi_generic_address data_addr;
                 unsigned long global_lock;
-                spinlock_t lock;
+                struct semaphore sem;
         } poll;
 };
 
@@ -323,7 +323,6 @@ static int acpi_ec_poll_read(union acpi_ec *ec, u8 address, u32 * data)
 {
         acpi_status status = AE_OK;
         int result = 0;
-        unsigned long flags = 0;
         u32 glk = 0;
 
         ACPI_FUNCTION_TRACE("acpi_ec_read");
@@ -339,8 +338,11 @@ static int acpi_ec_poll_read(union acpi_ec *ec, u8 address, u32 * data)
                         return_VALUE(-ENODEV);
         }
 
-        spin_lock_irqsave(&ec->poll.lock, flags);
-
+        if (down_interruptible(&ec->poll.sem)) {
+                result = -ERESTARTSYS;
+                goto end_nosem;
+        }
+        
         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
                                 &ec->common.command_addr);
         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
@@ -358,8 +360,8 @@ static int acpi_ec_poll_read(union acpi_ec *ec, u8 address, u32 * data)
                           *data, address));
 
       end:
-        spin_unlock_irqrestore(&ec->poll.lock, flags);
-
+        up(&ec->poll.sem);
+end_nosem:
         if (ec->common.global_lock)
                 acpi_release_global_lock(glk);
 
@@ -370,7 +372,6 @@ static int acpi_ec_poll_write(union acpi_ec *ec, u8 address, u8 data)
 {
         int result = 0;
         acpi_status status = AE_OK;
-        unsigned long flags = 0;
         u32 glk = 0;
 
         ACPI_FUNCTION_TRACE("acpi_ec_write");
@@ -384,8 +385,11 @@ static int acpi_ec_poll_write(union acpi_ec *ec, u8 address, u8 data)
                         return_VALUE(-ENODEV);
         }
 
-        spin_lock_irqsave(&ec->poll.lock, flags);
-
+        if (down_interruptible(&ec->poll.sem)) {
+                result = -ERESTARTSYS;
+                goto end_nosem;
+        }
+        
         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
                                 &ec->common.command_addr);
         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
@@ -406,8 +410,8 @@ static int acpi_ec_poll_write(union acpi_ec *ec, u8 address, u8 data)
                           data, address));
 
       end:
-        spin_unlock_irqrestore(&ec->poll.lock, flags);
-
+        up(&ec->poll.sem);
+end_nosem:
         if (ec->common.global_lock)
                 acpi_release_global_lock(glk);
 
@@ -568,7 +572,6 @@ static int acpi_ec_poll_query(union acpi_ec *ec, u32 * data)
 {
         int result = 0;
         acpi_status status = AE_OK;
-        unsigned long flags = 0;
         u32 glk = 0;
 
         ACPI_FUNCTION_TRACE("acpi_ec_query");
@@ -589,8 +592,11 @@ static int acpi_ec_poll_query(union acpi_ec *ec, u32 * data)
          * Note that successful completion of the query causes the ACPI_EC_SCI
          * bit to be cleared (and thus clearing the interrupt source).
          */
-        spin_lock_irqsave(&ec->poll.lock, flags);
-
+        if (down_interruptible(&ec->poll.sem)) {
+                result = -ERESTARTSYS;
+                goto end_nosem;
+        }
+        
         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
                                 &ec->common.command_addr);
         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
@@ -602,8 +608,8 @@ static int acpi_ec_poll_query(union acpi_ec *ec, u32 * data)
                 result = -ENODATA;
 
       end:
-        spin_unlock_irqrestore(&ec->poll.lock, flags);
-
+        up(&ec->poll.sem);
+end_nosem:
         if (ec->common.global_lock)
                 acpi_release_global_lock(glk);
 
@@ -680,7 +686,6 @@ static void acpi_ec_gpe_poll_query(void *ec_cxt)
 {
         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
         u32 value = 0;
-        unsigned long flags = 0;
         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
@@ -691,9 +696,11 @@ static void acpi_ec_gpe_poll_query(void *ec_cxt)
         if (!ec_cxt)
                 goto end;
 
-        spin_lock_irqsave(&ec->poll.lock, flags);
+        if (down_interruptible (&ec->poll.sem)) {
+                return_VOID;
+        }
         acpi_hw_low_level_read(8, &value, &ec->common.command_addr);
-        spin_unlock_irqrestore(&ec->poll.lock, flags);
+        up(&ec->poll.sem);
 
         /* TBD: Implement asynch events!
          * NOTE: All we care about are EC-SCI's.  Other EC events are
@@ -1005,7 +1012,7 @@ static int acpi_ec_poll_add(struct acpi_device *device)
 
         ec->common.handle = device->handle;
         ec->common.uid = -1;
-        spin_lock_init(&ec->poll.lock);
+        init_MUTEX(&ec->poll.sem);
         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
         acpi_driver_data(device) = ec;
@@ -1300,7 +1307,7 @@ acpi_fake_ecdt_poll_callback(acpi_handle handle,
                                   &ec_ecdt->common.gpe_bit);
         if (ACPI_FAILURE(status))
                 return status;
-        spin_lock_init(&ec_ecdt->poll.lock);
+        init_MUTEX(&ec_ecdt->poll.sem);
         ec_ecdt->common.global_lock = TRUE;
         ec_ecdt->common.handle = handle;
 
@@ -1416,7 +1423,7 @@ static int __init acpi_ec_poll_get_real_ecdt(void)
         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
-        spin_lock_init(&ec_ecdt->poll.lock);
+        init_MUTEX(&ec_ecdt->poll.sem);
         /* use the GL just to be safe */
         ec_ecdt->common.global_lock = TRUE;
         ec_ecdt->common.uid = ecdt_ptr->uid;