NAME¶
smp_read_gpio - invoke READ GPIO REGISTER (ENHANCED) SMP function
SYNOPSIS¶
smp_read_gpio [
--count=CO] [
--enhanced] [
--help]
[
--hex] [
--index=IN] [
--interface=PARAMS] [
--raw]
[
--sa=SAS_ADDR] [
--type=TY] [
--verbose] [
--version]
SMP_DEVICE[,N]
DESCRIPTION¶
Sends a SAS Management Protocol (SMP) READ GPIO REGISTER or READ GPIO REGISTER
ENHANCED function request to a SMP target. The SMP target is identified by the
SMP_DEVICE and the
SAS_ADDR. Depending on the interface, the
SAS_ADDR may be deduced from the
SMP_DEVICE. The mpt interface
uses
SMP_DEVICE to identify a HBA (an SMP initiator) and needs the
additional
,N to differentiate between HBAs if there are multiple
present.
This function is defined in SFF-8485 ( see www.sffcommittee.com ) together with
its corresponding WRITE GPIO REGISTER SMP function. The other SMP functions
are defined in SAS documents at www.t10.org . SFF-8485 defines a curious
device called a "virtual SMP port" that lives in a host bus adapter
(HBA) and allows SMP to manipulate the sideband signals on wide internal
cables. To stop other initiators in a multi-initiator domain from accessing
those sideband signals, the virtual SMP (target) port is not indicated in a
DISCOVER response.
In SAS-2 this function was made obsolete and seemingly replaced by a function
called READ GPIO REGISTER ENHANCED with a reference to the same SFF document.
However the author can find no version of SFF-8485 that defines the READ GPIO
REGISTER ENHANCED function. In SAS-2.1 both the READ GPIO REGISTER and READ
GPIO REGISTER ENHANCED functions were dropped.
OPTIONS¶
Mandatory arguments to long options are mandatory for short options as well.
- -c, --count=CO
- where CO is the register count. This is the number
of (4 byte) registers to request. The default value is 1.
- -E, --enhanced
- sends a READ GPIO REGISTER ENHANCED function request
(default: send a READ GPIO REGISTER function request).
- -h, --help
- output the usage message then exit.
- -H, --hex
- output the response (less the CRC field) in
hexadecimal.
- -i, --index=IN
- where IN is the register index. This value is origin
zero and its default value is 0. If the request succeeds, then
--count=CO registers starting from --index=IN of the given
--type=TY should be in the response.
- -I, --interface=PARAMS
- interface specific parameters. In this case
"interface" refers to the path through the operating system to
the SMP initiator. See the smp_utils man page for more information.
- -r, --raw
- send the response (less the CRC field) to stdout in binary.
All error messages are sent to stderr.
- -s, --sa=SAS_ADDR
- specifies the SAS address of the SMP target device.
Typically this is an expander. This option may not be needed if the
SMP_DEVICE has the target's SAS address within it. The
SAS_ADDR is in decimal but most SAS addresses are shown in
hexadecimal. To give a number in hexadecimal either prefix it with '0x' or
put a trailing 'h' on it.
- -t, --type=TY
- where TY is the register type. The default value is
0 (GPIO_CFG). If the request succeeds, then --count=CO registers
starting from --index=IN of the given --type=TY should be in
the response.
- -v, --verbose
- increase the verbosity of the output. Can be used multiple
times
- -V, --version
- print the version string and then exit.
EXAMPLES¶
See "Examples" section in
http://sg.danny.cz/sg/smp_utils.html
The SMP READ GPIO REGISTER (ENHANCED) function is defined in SFF-8485 (see
www.sffcommittee.com ) together with its corresponding WRITE GPIO REGISTER
(ENHANCED) SMP function.
AUTHORS¶
Written by Douglas Gilbert.
REPORTING BUGS¶
Report bugs to <dgilbert at interlog dot com>.
COPYRIGHT¶
Copyright © 2006-2011 Douglas Gilbert
This software is distributed under a FreeBSD license. There is NO warranty; not
even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
SEE ALSO¶
smp_utils, smp_write_gpio(smp_utils)