smp_read_gpio(8)

1SMP_READ_GPIO(8)                   SMP_UTILS                  SMP_READ_GPIO(8)
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NAME

6       smp_read_gpio - invoke READ GPIO REGISTER (ENHANCED) SMP function
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SYNOPSIS

9       smp_read_gpio  [--count=CO]  [--enhanced] [--help] [--hex] [--index=IN]
10       [--interface=PARAMS] [--raw]  [--sa=SAS_ADDR]  [--type=TY]  [--verbose]
11       [--version] SMP_DEVICE[,N]
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DESCRIPTION

14       Sends a SAS Serial Management Protocol (SMP) READ GPIO REGISTER or READ
15       GPIO REGISTER ENHANCED function request to an SMP target. The SMP  tar‐
16       get  is identified by the SMP_DEVICE and the SAS_ADDR. Depending on the
17       interface, the SAS_ADDR may be deduced from  the  SMP_DEVICE.  The  mpt
18       interface  uses  SMP_DEVICE  to  identify  a HBA (an SMP initiator) and
19       needs the additional ,N to differentiate between HBAs if there are mul‐
20       tiple present.
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22       This  function  is  defined  in  SFF-8485  ( see www.sffcommittee.com )
23       together with its corresponding WRITE GPIO REGISTER SMP function.   The
24       other  SMP  functions  are  defined  in  SAS documents at www.t10.org .
25       SFF-8485 defines a curious device called  a  "virtual  SMP  port"  that
26       lives  in  a  host  bus  adapter (HBA) and allows SMP to manipulate the
27       sideband signals on wide internal cables. To stop other initiators in a
28       multi-initiator  domain from accessing those sideband signals, the vir‐
29       tual SMP (target) port is not indicated in a DISCOVER response.
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31       For notes on the SMP READ GPIO REGISTER ENHANCED function see the  sec‐
32       tion on the ENHANCED FUNCTION below.
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OPTIONS

35       Mandatory  arguments to long options are mandatory for short options as
36       well.
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38       -c, --count=CO
39              where CO is the register count. This is the number of  (4  byte)
40              registers to request. The default value is 1.
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42       -E, --enhanced
43              sends  a  READ GPIO REGISTER ENHANCED function request (default:
44              send a READ GPIO REGISTER function request).
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46       -h, --help
47              output the usage message then exit.
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49       -H, --hex
50              output the response (less the CRC field) in hexadecimal.
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52       -i, --index=IN
53              where IN is the register index. This value is  origin  zero  and
54              its default value is 0. If the request succeeds, then --count=CO
55              registers starting from --index=IN of the given --type=TY should
56              be in the response.
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58       -I, --interface=PARAMS
59              interface  specific  parameters. In this case "interface" refers
60              to the path through the operating system to the  SMP  initiator.
61              See the smp_utils man page for more information.
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63       -r, --raw
64              send  the response (less the CRC field) to stdout in binary. All
65              error messages are sent to stderr.
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67       -s, --sa=SAS_ADDR
68              specifies the SAS address of the SMP  target  device.  Typically
69              this  is  an  expander.  This  option  may  not be needed if the
70              SMP_DEVICE has the target's SAS address within it. The  SAS_ADDR
71              is  in  decimal but most SAS addresses are shown in hexadecimal.
72              To give a number in hexadecimal either prefix it  with  '0x'  or
73              put a trailing 'h' on it.
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75       -t, --type=TY
76              where   TY  is  the  register  type.  The  default  value  is  0
77              (GPIO_CFG).  If the request succeeds, then --count=CO  registers
78              starting from --index=IN of the given --type=TY should be in the
79              response.
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81       -v, --verbose
82              increase the verbosity of the output. Can be used multiple times
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84       -V, --version
85              print the version string and then exit.
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ENHANCED FUNCTION

88       In the technical review of SAS-2 prior to standardization in  this  t10
89       document:  08-212r8.pdf  (page  871 or 552) there is a comment that the
90       READ GPIO REGISTER and WRITE GPIO REGISTER function headers (i.e. first
91       4 bytes) do not comply with all the other SMP functions in SAS-2.
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93       There  is a suggestion that enhanced variants be introduced in the next
94       version of the SFF-8485 document. If that ever happened then it has not
95       been  made  public.  In  SAS-2.1  both the READ and WRITE GPIO REGISTER
96       functions have been made obsolete and the corresponding ENHANCED  func‐
97       tion numbers are "restricted" for SFF-8485.
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99       If  the --enhanced option is given then the ENHANCED function number is
100       sent; the register type, index and count  fields  (1   byte  each)  are
101       increased  by  two  byte positions leaving enough space for a compliant
102       SAS-2 SMP header to be built.
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EXAMPLES

105       See "Examples" section in http://sg.danny.cz/sg/smp_utils.html
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CONFORMING TO

108       The SMP READ GPIO REGISTER (ENHANCED) function is defined  in  SFF-8485
109       (see  www.sffcommittee.com ) together with its corresponding WRITE GPIO
110       REGISTER (ENHANCED) SMP function.
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AUTHORS

113       Written by Douglas Gilbert.
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REPORTING BUGS

116       Report bugs to <dgilbert at interlog dot com>.
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COPYRIGHT

119       Copyright © 2006-2011 Douglas Gilbert
120       This software is distributed under a FreeBSD license. There is NO  war‐
121       ranty;  not  even  for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR‐
122       POSE.
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