1 files changed, 46 insertions, 9 deletions

diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c
index 4fc471ce173e..cb418140cbbe 100644
--- a/drivers/i2c/busses/i2c-octeon.c
+++ b/drivers/i2c/busses/i2c-octeon.c
@@ -109,6 +109,8 @@
 #define TWSI_INT_SDA            BIT_ULL(10)
 #define TWSI_INT_SCL            BIT_ULL(11)
 
+#define I2C_OCTEON_EVENT_WAIT 80 /* microseconds */
+
 struct octeon_i2c {
         wait_queue_head_t queue;
         struct i2c_adapter adap;
@@ -339,11 +341,29 @@ static irqreturn_t octeon_i2c_hlc_isr78(int irq, void *dev_id)
         return IRQ_HANDLED;
 }
 
-static int octeon_i2c_test_iflg(struct octeon_i2c *i2c)
+static bool octeon_i2c_test_iflg(struct octeon_i2c *i2c)
 {
         return (octeon_i2c_ctl_read(i2c) & TWSI_CTL_IFLG);
 }
 
+static bool octeon_i2c_test_ready(struct octeon_i2c *i2c, bool *first)
+{
+        if (octeon_i2c_test_iflg(i2c))
+                return true;
+
+        if (*first) {
+                *first = false;
+                return false;
+        }
+
+        /*
+         * IRQ has signaled an event but IFLG hasn't changed.
+         * Sleep and retry once.
+         */
+        usleep_range(I2C_OCTEON_EVENT_WAIT, 2 * I2C_OCTEON_EVENT_WAIT);
+        return octeon_i2c_test_iflg(i2c);
+}
+
 /**
  * octeon_i2c_wait - wait for the IFLG to be set
  * @i2c: The struct octeon_i2c
@@ -353,15 +373,14 @@ static int octeon_i2c_test_iflg(struct octeon_i2c *i2c)
 static int octeon_i2c_wait(struct octeon_i2c *i2c)
 {
         long time_left;
+        bool first = 1;
 
         i2c->int_enable(i2c);
-        time_left = wait_event_timeout(i2c->queue, octeon_i2c_test_iflg(i2c),
+        time_left = wait_event_timeout(i2c->queue, octeon_i2c_test_ready(i2c, &first),
                                        i2c->adap.timeout);
         i2c->int_disable(i2c);
-        if (!time_left) {
-                dev_dbg(i2c->dev, "%s: timeout\n", __func__);
+        if (!time_left)
                 return -ETIMEDOUT;
-        }
 
         return 0;
 }
@@ -427,11 +446,28 @@ static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
         }
 }
 
-static bool octeon_i2c_hlc_test_ready(struct octeon_i2c *i2c)
+static bool octeon_i2c_hlc_test_valid(struct octeon_i2c *i2c)
+{
+        return (__raw_readq(i2c->twsi_base + SW_TWSI) & SW_TWSI_V) == 0;
+}
+
+static bool octeon_i2c_hlc_test_ready(struct octeon_i2c *i2c, bool *first)
 {
-        u64 val = __raw_readq(i2c->twsi_base + SW_TWSI);
+        /* check if valid bit is cleared */
+        if (octeon_i2c_hlc_test_valid(i2c))
+                return true;
 
-        return (val & SW_TWSI_V) == 0;
+        if (*first) {
+                *first = false;
+                return false;
+        }
+
+        /*
+         * IRQ has signaled an event but valid bit isn't cleared.
+         * Sleep and retry once.
+         */
+        usleep_range(I2C_OCTEON_EVENT_WAIT, 2 * I2C_OCTEON_EVENT_WAIT);
+        return octeon_i2c_hlc_test_valid(i2c);
 }
 
 static void octeon_i2c_hlc_int_enable(struct octeon_i2c *i2c)
@@ -453,11 +489,12 @@ static void octeon_i2c_hlc_int_clear(struct octeon_i2c *i2c)
  */
 static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
 {
+        bool first = 1;
         int time_left;
 
         i2c->hlc_int_enable(i2c);
         time_left = wait_event_timeout(i2c->queue,
-                                       octeon_i2c_hlc_test_ready(i2c),
+                                       octeon_i2c_hlc_test_ready(i2c, &first),
                                        i2c->adap.timeout);
         i2c->hlc_int_disable(i2c);
         if (!time_left) {