[PATCH] w1: Added w1_reset_select_slave() - Resets the bus and then selects the slave by

sending either a skip rom or a rom match.

Patch from Ben Gardner <bgardner@wabtec.com>

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/w1/w1_io.c b/drivers/w1/w1_io.c
index 00f032220173..e2a043354ddf 100644
--- a/drivers/w1/w1_io.c
+++ b/drivers/w1/w1_io.c
@@ -277,6 +277,29 @@ void w1_search_devices(struct w1_master *dev, w1_slave_found_callback cb)
                 w1_search(dev, cb);
 }
 
+/**
+ * Resets the bus and then selects the slave by sending either a skip rom
+ * or a rom match.
+ * The w1 master lock must be held.
+ *
+ * @param sl    the slave to select
+ * @return      0=success, anything else=error
+ */
+int w1_reset_select_slave(struct w1_slave *sl)
+{
+        if (w1_reset_bus(sl->master))
+                return -1;
+
+        if (sl->master->slave_count == 1)
+                w1_write_8(sl->master, W1_SKIP_ROM);
+        else {
+                u8 match[9] = {W1_MATCH_ROM, };
+                memcpy(&match[1], (u8 *)&sl->reg_num, 8);
+                w1_write_block(sl->master, match, 9);
+        }
+        return 0;
+}
+
 EXPORT_SYMBOL(w1_touch_bit);
 EXPORT_SYMBOL(w1_write_8);
 EXPORT_SYMBOL(w1_read_8);
@@ -286,3 +309,4 @@ EXPORT_SYMBOL(w1_delay);
 EXPORT_SYMBOL(w1_read_block);
 EXPORT_SYMBOL(w1_write_block);
 EXPORT_SYMBOL(w1_search_devices);
+EXPORT_SYMBOL(w1_reset_select_slave);