1 files changed, 24 insertions, 2 deletions

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 5f1b92c74bd9..c0b9aa7df0e2 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -37,6 +37,7 @@
 #define I2C_CNFG                                0x000
 #define I2C_CNFG_PACKET_MODE_EN                 (1<<10)
 #define I2C_CNFG_NEW_MASTER_FSM                 (1<<11)
+#define I2C_STATUS                              0x01C
 #define I2C_SL_CNFG                             0x020
 #define I2C_SL_CNFG_NEWSL                       (1<<2)
 #define I2C_SL_ADDR1                            0x02c
@@ -77,6 +78,7 @@
 #define I2C_ERR_NONE                            0x00
 #define I2C_ERR_NO_ACK                          0x01
 #define I2C_ERR_ARBITRATION_LOST                0x02
+#define I2C_ERR_UNKNOWN_INTERRUPT               0x04
 
 #define PACKET_HEADER0_HEADER_SIZE_SHIFT        28
 #define PACKET_HEADER0_PACKET_ID_SHIFT          16
@@ -121,6 +123,7 @@ struct tegra_i2c_dev {
         void __iomem *base;
         int cont_id;
         int irq;
+        bool irq_disabled;
         int is_dvc;
         struct completion msg_complete;
         int msg_err;
@@ -343,6 +346,12 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
                 err = -ETIMEDOUT;
 
         clk_disable(i2c_dev->clk);
+
+        if (i2c_dev->irq_disabled) {
+                i2c_dev->irq_disabled = 0;
+                enable_irq(i2c_dev->irq);
+        }
+
         return err;
 }
 
@@ -355,8 +364,19 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
         status = i2c_readl(i2c_dev, I2C_INT_STATUS);
 
         if (status == 0) {
-                dev_warn(i2c_dev->dev, "interrupt with no status\n");
-                return IRQ_NONE;
+                dev_warn(i2c_dev->dev, "irq status 0 %08x %08x %08x\n",
+                         i2c_readl(i2c_dev, I2C_PACKET_TRANSFER_STATUS),
+                         i2c_readl(i2c_dev, I2C_STATUS),
+                         i2c_readl(i2c_dev, I2C_CNFG));
+                i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT;
+
+                if (!i2c_dev->irq_disabled) {
+                        disable_irq_nosync(i2c_dev->irq);
+                        i2c_dev->irq_disabled = 1;
+                }
+
+                complete(&i2c_dev->msg_complete);
+                goto err;
         }
 
         if (unlikely(status & status_err)) {
@@ -396,6 +416,8 @@ err:
                 I2C_INT_PACKET_XFER_COMPLETE | I2C_INT_TX_FIFO_DATA_REQ |
                 I2C_INT_RX_FIFO_DATA_REQ);
         i2c_writel(i2c_dev, status, I2C_INT_STATUS);
+        if (i2c_dev->is_dvc)
+                dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
         return IRQ_HANDLED;
 }