]> git.karo-electronics.de Git - karo-tx-uboot.git/blobdiff - drivers/i2c/omap24xx_i2c.c
Revert "I2C: OMAP: detect more devices when probing an i2c bus"
[karo-tx-uboot.git] / drivers / i2c / omap24xx_i2c.c
index a7ffd95d5d7f4d19d82a5041d88774e66f21ce1a..3a50417b597d9451e2bdab60120b8db686d2c7c2 100644 (file)
@@ -255,23 +255,43 @@ int i2c_probe(uchar chip)
        /* wait until bus not busy */
        wait_for_bb();
 
-       /* try to write one byte */
+       /* try to read one byte */
        writew(1, &i2c_base->cnt);
        /* set slave address */
        writew(chip, &i2c_base->sa);
        /* stop bit needed here */
-       writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
-              I2C_CON_STP, &i2c_base->con);
-
-       status = wait_for_pin();
+       writew (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP, &i2c_base->con);
 
-       /* check for ACK (!NAK) */
-       if (!(status & I2C_STAT_NACK))
-               res = 0;
-
-       /* abort transfer (force idle state) */
-       writew(0, &i2c_base->con);
+       while (1) {
+               status = wait_for_pin();
+               if (status == 0 || status & I2C_STAT_AL) {
+                       res = 1;
+                       goto probe_exit;
+               }
+               if (status & I2C_STAT_NACK) {
+                       res = 1;
+                       writew(0xff, &i2c_base->stat);
+                       writew (readw (&i2c_base->con) | I2C_CON_STP, &i2c_base->con);
+                       wait_for_bb ();
+                       break;
+               }
+               if (status & I2C_STAT_ARDY) {
+                       writew(I2C_STAT_ARDY, &i2c_base->stat);
+                       break;
+               }
+               if (status & I2C_STAT_RRDY) {
+                       res = 0;
+#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
+    defined(CONFIG_OMAP44XX)
+                       readb(&i2c_base->data);
+#else
+                       readw(&i2c_base->data);
+#endif
+                       writew(I2C_STAT_RRDY, &i2c_base->stat);
+               }
+       }
 
+probe_exit:
        flush_fifo();
        /* don't allow any more data in... we don't want it. */
        writew(0, &i2c_base->cnt);