w1: ds2490 fix and enable hardware search

The hardware search was failing without the COMM_RST flag.  Enabled
the flag and rewrote the function to handle more than one buffer of
results and to continuing where the search left off.  Remove hardware
search note from the limitations now that it works.  The "w1: ds2490
USB setup fixes" change went from 23.16 seconds to about 3 seconds,
this takes the time for the search down to .307346 seconds.

Signed-off-by: David Fries <[email protected]>
Acked-by: Evgeniy Polyakov <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This commit is contained in:
David Fries 2014-01-15 22:29:23 -06:00 • committed by Greg Kroah-Hartman
commit d53f0a2c05
2 changed files with 86 additions and 24 deletions

View file

@ -21,8 +21,6 @@ Notes and limitations.
- The weak pullup current is a minimum of 0.9mA and maximum of 6.0mA.
- The 5V strong pullup is supported with a minimum of 5.9mA and a
maximum of 30.4 mA. (From DS2490.pdf)
- While the ds2490 supports a hardware search the code doesn't take
advantage of it (in tested case it only returned first device).
- The hardware will detect when devices are attached to the bus on the
next bus (reset?) operation, however only a message is printed as
the core w1 code doesn't make use of the information. Connecting