USB: cxacru: add write-only sysfs attribute for modem configuration
The modem can be configured using CM_REQUEST_CARD_DATA_SET,
although CM_REQUEST_CARD_DATA_GET does not return any data.
Tested by setting the modulation (0x0a) option.
There is a list of parameters in the following archive,
but the meaning of many of them is not well documented:
http://sourceforge.net/project/shownotes.php?release_id=301825
This source also indicates that the highest parameter set
is 0x4a but this varies by model so an arbitrary limit of
0x7f has been used (the index is a 32-bit integer).
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/Documentation/networking/cxacru.txt b/Documentation/networking/cxacru.txt
index 3532cee..f4fbf4c 100644
--- a/Documentation/networking/cxacru.txt
+++ b/Documentation/networking/cxacru.txt
@@ -15,6 +15,15 @@
* adsl_headend_environment
Information about the remote headend.
+* adsl_config
+ Configuration writing interface.
+ Write parameters in hexadecimal format <index>=<value>,
+ separated by whitespace, e.g.:
+ "1=0 a=5"
+ Up to 7 parameters at a time will be sent and the modem will restart
+ the ADSL connection when any value is set. These are logged for future
+ reference.
+
* downstream_attenuation (dB)
* downstream_bits_per_frame
* downstream_rate (kbps)