W1: ds2490.c disable bit read and write

[karo-tx-linux.git] / drivers / w1 / masters / ds2490.c

diff --git a/drivers/w1/masters/ds2490.c b/drivers/w1/masters/ds2490.c
index 6fabf584395fc110930da5342f1b12e819d45c77..1b632d549e790b242920440a624377d7afead906 100644 (file)
--- a/drivers/w1/masters/ds2490.c
+++ b/drivers/w1/masters/ds2490.c
@@ -520,6 +520,7 @@ static int ds_touch_bit(struct ds_device *dev, u8 bit, u8 *tbit)
        return 0;
 }
 
+#if 0
 static int ds_write_bit(struct ds_device *dev, u8 bit)
 {
        int err;
@@ -538,6 +539,7 @@ static int ds_write_bit(struct ds_device *dev, u8 bit)
 
        return 0;
 }
+#endif
 
 static int ds_write_byte(struct ds_device *dev, u8 byte)
 {
@@ -722,6 +724,7 @@ static u8 ds9490r_touch_bit(void *data, u8 bit)
        return ret;
 }
 
+#if 0
 static void ds9490r_write_bit(void *data, u8 bit)
 {
        struct ds_device *dev = data;
@@ -729,13 +732,6 @@ static void ds9490r_write_bit(void *data, u8 bit)
        ds_write_bit(dev, bit);
 }
 
-static void ds9490r_write_byte(void *data, u8 byte)
-{
-       struct ds_device *dev = data;
-
-       ds_write_byte(dev, byte);
-}
-
 static u8 ds9490r_read_bit(void *data)
 {
        struct ds_device *dev = data;
@@ -748,6 +744,14 @@ static u8 ds9490r_read_bit(void *data)
 
        return bit & 1;
 }
+#endif
+
+static void ds9490r_write_byte(void *data, u8 byte)
+{
+       struct ds_device *dev = data;
+
+       ds_write_byte(dev, byte);
+}
 
 static u8 ds9490r_read_byte(void *data)
 {
@@ -812,8 +816,15 @@ static int ds_w1_init(struct ds_device *dev)
 
        dev->master.data        = dev;
        dev->master.touch_bit   = &ds9490r_touch_bit;
+       /* read_bit and write_bit in w1_bus_master are expected to set and
+        * sample the line level.  For write_bit that means it is expected to
+        * set it to that value and leave it there.  ds2490 only supports an
+        * individual time slot at the lowest level.  The requirement from
+        * pulling the bus state down to reading the state is 15us, something
+        * that isn't realistic on the USB bus anyway.
        dev->master.read_bit    = &ds9490r_read_bit;
        dev->master.write_bit   = &ds9490r_write_bit;
+       */
        dev->master.read_byte   = &ds9490r_read_byte;
        dev->master.write_byte  = &ds9490r_write_byte;
        dev->master.read_block  = &ds9490r_read_block;