1 files changed, 21 insertions, 19 deletions

diff --git a/drivers/i2c/busses/i2c-designware-baytrail.c b/drivers/i2c/busses/i2c-designware-baytrail.c
index 5f1ff4cc5c34..7d7ae97476e2 100644
--- a/drivers/i2c/busses/i2c-designware-baytrail.c
+++ b/drivers/i2c/busses/i2c-designware-baytrail.c
@@ -17,27 +17,31 @@
 #include <linux/acpi.h>
 #include <linux/i2c.h>
 #include <linux/interrupt.h>
+
 #include <asm/iosf_mbi.h>
+
 #include "i2c-designware-core.h"
 
 #define SEMAPHORE_TIMEOUT       100
 #define PUNIT_SEMAPHORE         0x7
+#define PUNIT_SEMAPHORE_BIT     BIT(0)
+#define PUNIT_SEMAPHORE_ACQUIRE BIT(1)
 
 static unsigned long acquired;
 
 static int get_sem(struct device *dev, u32 *sem)
 {
-        u32 reg_val;
+        u32 data;
         int ret;
 
         ret = iosf_mbi_read(BT_MBI_UNIT_PMC, BT_MBI_BUNIT_READ, PUNIT_SEMAPHORE,
-                            &reg_val);
+                                &data);
         if (ret) {
                 dev_err(dev, "iosf failed to read punit semaphore\n");
                 return ret;
         }
 
-        *sem = reg_val & 0x1;
+        *sem = data & PUNIT_SEMAPHORE_BIT;
 
         return 0;
 }
@@ -52,27 +56,29 @@ static void reset_semaphore(struct device *dev)
                 return;
         }
 
-        data = data & 0xfffffffe;
+        data &= ~PUNIT_SEMAPHORE_BIT;
         if (iosf_mbi_write(BT_MBI_UNIT_PMC, BT_MBI_BUNIT_WRITE,
-                                 PUNIT_SEMAPHORE, data))
+                                PUNIT_SEMAPHORE, data))
                 dev_err(dev, "iosf failed to reset punit semaphore during write\n");
 }
 
-int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
+static int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
 {
-        u32 sem = 0;
+        u32 sem;
         int ret;
         unsigned long start, end;
 
+        might_sleep();
+
         if (!dev || !dev->dev)
                 return -ENODEV;
 
-        if (!dev->acquire_lock)
+        if (!dev->release_lock)
                 return 0;
 
-        /* host driver writes 0x2 to side band semaphore register */
+        /* host driver writes to side band semaphore register */
         ret = iosf_mbi_write(BT_MBI_UNIT_PMC, BT_MBI_BUNIT_WRITE,
-                                 PUNIT_SEMAPHORE, 0x2);
+                                PUNIT_SEMAPHORE, PUNIT_SEMAPHORE_ACQUIRE);
         if (ret) {
                 dev_err(dev->dev, "iosf punit semaphore request failed\n");
                 return ret;
@@ -81,7 +87,7 @@ int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
         /* host driver waits for bit 0 to be set in semaphore register */
         start = jiffies;
         end = start + msecs_to_jiffies(SEMAPHORE_TIMEOUT);
-        while (!time_after(jiffies, end)) {
+        do {
                 ret = get_sem(dev->dev, &sem);
                 if (!ret && sem) {
                         acquired = jiffies;
@@ -91,14 +97,14 @@ int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
                 }
 
                 usleep_range(1000, 2000);
-        }
+        } while (time_before(jiffies, end));
 
         dev_err(dev->dev, "punit semaphore timed out, resetting\n");
         reset_semaphore(dev->dev);
 
         ret = iosf_mbi_read(BT_MBI_UNIT_PMC, BT_MBI_BUNIT_READ,
-                PUNIT_SEMAPHORE, &sem);
-        if (!ret)
+                                PUNIT_SEMAPHORE, &sem);
+        if (ret)
                 dev_err(dev->dev, "iosf failed to read punit semaphore\n");
         else
                 dev_err(dev->dev, "PUNIT SEM: %d\n", sem);
@@ -107,9 +113,8 @@ int baytrail_i2c_acquire(struct dw_i2c_dev *dev)
 
         return -ETIMEDOUT;
 }
-EXPORT_SYMBOL(baytrail_i2c_acquire);
 
-void baytrail_i2c_release(struct dw_i2c_dev *dev)
+static void baytrail_i2c_release(struct dw_i2c_dev *dev)
 {
         if (!dev || !dev->dev)
                 return;
@@ -121,7 +126,6 @@ void baytrail_i2c_release(struct dw_i2c_dev *dev)
         dev_dbg(dev->dev, "punit semaphore held for %ums\n",
                 jiffies_to_msecs(jiffies - acquired));
 }
-EXPORT_SYMBOL(baytrail_i2c_release);
 
 int i2c_dw_eval_lock_support(struct dw_i2c_dev *dev)
 {
@@ -137,7 +141,6 @@ int i2c_dw_eval_lock_support(struct dw_i2c_dev *dev)
                 return 0;
 
         status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);
-
         if (ACPI_FAILURE(status))
                 return 0;
 
@@ -153,7 +156,6 @@ int i2c_dw_eval_lock_support(struct dw_i2c_dev *dev)
 
         return 0;
 }
-EXPORT_SYMBOL(i2c_dw_eval_lock_support);
 
 MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>");
 MODULE_DESCRIPTION("Baytrail I2C Semaphore driver");