1 files changed, 40 insertions, 0 deletions

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 00fd02ec1b65..fdba13137daf 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -166,6 +166,8 @@ enum {
 #define SYSC_IDLEMODE_SMART             0x2
 #define SYSC_CLOCKACTIVITY_FCLK         0x2
 
+/* Errata definitions */
+#define I2C_OMAP_ERRATA_I207            (1 << 0)
 
 struct omap_i2c_dev {
         struct device           *dev;
@@ -199,6 +201,7 @@ struct omap_i2c_dev {
         u16                     bufstate;
         u16                     syscstate;
         u16                     westate;
+        u16                     errata;
 };
 
 const static u8 reg_map[] = {
@@ -498,6 +501,11 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
         /* Take the I2C module out of reset: */
         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 
+        dev->errata = 0;
+
+        if (cpu_is_omap2430() || cpu_is_omap34xx())
+                dev->errata |= I2C_OMAP_ERRATA_I207;
+
         /* Enable interrupts */
         dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
                         OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
@@ -695,6 +703,34 @@ omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
         omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
 }
 
+static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
+{
+        /*
+         * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
+         * Not applicable for OMAP4.
+         * Under certain rare conditions, RDR could be set again
+         * when the bus is busy, then ignore the interrupt and
+         * clear the interrupt.
+         */
+        if (stat & OMAP_I2C_STAT_RDR) {
+                /* Step 1: If RDR is set, clear it */
+                omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
+
+                /* Step 2: */
+                if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
+                                                & OMAP_I2C_STAT_BB)) {
+
+                        /* Step 3: */
+                        if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
+                                                & OMAP_I2C_STAT_RDR) {
+                                omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
+                                dev_dbg(dev->dev, "RDR when bus is busy.\n");
+                        }
+
+                }
+        }
+}
+
 /* rev1 devices are apparently only on some 15xx */
 #ifdef CONFIG_ARCH_OMAP15XX
 
@@ -834,6 +870,10 @@ complete:
                 }
                 if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
                         u8 num_bytes = 1;
+
+                        if (dev->errata & I2C_OMAP_ERRATA_I207)
+                                i2c_omap_errata_i207(dev, stat);
+
                         if (dev->fifo_size) {
                                 if (stat & OMAP_I2C_STAT_RRDY)
                                         num_bytes = dev->fifo_size;