i2c: i2c-omap: Fix BUFSTAT_REG reading

The number of bytes to be received is read from wrong
place with all OMAPs with highspeed I2C support,
which involves a FIFO and BUFSTAT_REG. It is the 6
bits starting from the bit 8 in the BUFSTAT_REG
that indicate this amount of bytes to be read.
Moreover, only the 6 LSB:s are relevant for the
TXSTAT field.
Signed-off-by: Eero Nurkkala <ext-eero.nurkkala@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

drivers/i2c/busses/i2c-omap.c

@@ -675,8 +675,9 @@ omap_i2c_isr(int this_irq, void *dev_id)
 				if (stat & OMAP_I2C_STAT_RRDY)
 					num_bytes = dev->fifo_size;
 				else
-					num_bytes = omap_i2c_read_reg(dev,
-							OMAP_I2C_BUFSTAT_REG);
+					num_bytes = (omap_i2c_read_reg(dev,
+							OMAP_I2C_BUFSTAT_REG)
+							>> 8) & 0x3F;
 			}
 			while (num_bytes) {
 				num_bytes--;
@@ -714,8 +715,9 @@ omap_i2c_isr(int this_irq, void *dev_id)
 				if (stat & OMAP_I2C_STAT_XRDY)
 					num_bytes = dev->fifo_size;
 				else
-					num_bytes = omap_i2c_read_reg(dev,
-							OMAP_I2C_BUFSTAT_REG);
+					num_bytes = (omap_i2c_read_reg(dev,
+							OMAP_I2C_BUFSTAT_REG))
+							& 0x3F;
 			}
 			while (num_bytes) {
 				num_bytes--;