OMAP3: I2C: Errata i207: Clear wrong RDR interrupt

Commit Message

manjugk manjugk April 1, 2010, 12:20 p.m. UTC

None

Patch

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index f2019d2..acf4076 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -796,6 +796,19 @@  complete:
 		}
 		if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
 			u8 num_bytes = 1;
+
+			/*
+			 * OMAP3 I2C Errata ID: i207
+			 * Under certain rare conditions, RDR could be set again
+			 * when the bus is busy, then clear and ignore the interrupt
+			 */
+			if (!(stat & OMAP_I2C_STAT_RRDY) && (stat &
+						OMAP_I2C_STAT_BB)) {
+				/* clear RDR */
+				omap_i2c_ack_stat(dev, stat & OMAP_I2C_STAT_RDR);
+				dev_err(dev->dev, "I2C: RDR when bus is busy.\n");
+				return IRQ_HANDLED;
+			}
 			if (dev->fifo_size) {
 				if (stat & OMAP_I2C_STAT_RRDY)
 					num_bytes = dev->fifo_size;