Merge nommu tree

[karo-tx-linux.git] / drivers / w1 / w1_io.c

diff --git a/drivers/w1/w1_io.c b/drivers/w1/w1_io.c
index 00f032220173863c3603dbc0d5f66ca005f9adb0..f7f7e8bec30eb9312adf50ffe07e995259c2db00 100644 (file)
--- a/drivers/w1/w1_io.c
+++ b/drivers/w1/w1_io.c
@@ -28,7 +28,7 @@
 #include "w1_log.h"
 #include "w1_io.h"
 
-int w1_delay_parm = 1;
+static int w1_delay_parm = 1;
 module_param_named(delay_coef, w1_delay_parm, int, 0);
 
 static u8 w1_crc8_table[] = {
@@ -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);