[PATCH] w1: Added the triplet w1 master method and changes w1_search() to use it.
Adds the triplet w1 master method and changes w1_search() to use it.
Signed-off-by: Ben Gardner <bgardner@wabtec.com>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/w1/w1_io.c b/drivers/w1/w1_io.c
index 2173336..00f0322 100644
--- a/drivers/w1/w1_io.c
+++ b/drivers/w1/w1_io.c
@@ -130,6 +130,47 @@
}
/**
+ * Does a triplet - used for searching ROM addresses.
+ * Return bits:
+ * bit 0 = id_bit
+ * bit 1 = comp_bit
+ * bit 2 = dir_taken
+ * If both bits 0 & 1 are set, the search should be restarted.
+ *
+ * @param dev the master device
+ * @param bdir the bit to write if both id_bit and comp_bit are 0
+ * @return bit fields - see above
+ */
+u8 w1_triplet(struct w1_master *dev, int bdir)
+{
+ if ( dev->bus_master->triplet )
+ return(dev->bus_master->triplet(dev->bus_master->data, bdir));
+ else {
+ u8 id_bit = w1_touch_bit(dev, 1);
+ u8 comp_bit = w1_touch_bit(dev, 1);
+ u8 retval;
+
+ if ( id_bit && comp_bit )
+ return(0x03); /* error */
+
+ if ( !id_bit && !comp_bit ) {
+ /* Both bits are valid, take the direction given */
+ retval = bdir ? 0x04 : 0;
+ } else {
+ /* Only one bit is valid, take that direction */
+ bdir = id_bit;
+ retval = id_bit ? 0x05 : 0x02;
+ }
+
+ if ( dev->bus_master->touch_bit )
+ w1_touch_bit(dev, bdir);
+ else
+ w1_write_bit(dev, bdir);
+ return(retval);
+ }
+}
+
+/**
* Reads 8 bits.
*
* @param dev the master device
@@ -233,7 +274,7 @@
if (dev->bus_master->search)
dev->bus_master->search(dev->bus_master->data, cb);
else
- w1_search(dev);
+ w1_search(dev, cb);
}
EXPORT_SYMBOL(w1_touch_bit);