xref: /freebsd/usr.sbin/spi/spi.8 (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
1.\" Copyright (c) 2018 by S.F.T. Inc.
2.\"
3.\" Redistribution and use in source and binary forms, with or without
4.\" modification, are permitted provided that the following conditions
5.\" are met:
6.\" 1. Redistributions of source code must retain the above copyright
7.\"    notice, this list of conditions and the following disclaimer.
8.\" 2. Redistributions in binary form must reproduce the above copyright
9.\"    notice, this list of conditions and the following disclaimer in the
10.\"    documentation and/or other materials provided with the distribution.
11.\"
12.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
13.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
14.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
15.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
16.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
17.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
18.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
19.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
20.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
21.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
22.\" SUCH DAMAGE.
23.\"
24.Dd August 21, 2020
25.Dt SPI 8
26.Os
27.Sh NAME
28.Nm spi
29.Nd communicate on SPI bus with slave devices
30.Sh SYNOPSIS
31.Nm
32.Op Fl A
33.Op Fl b
34.Op Fl L
35.Op Fl v
36.Op Fl C Ar command-bytes
37.Op Fl c Ar count
38.Op Fl d Cm r Ns | Ns Cm w Ns | Ns Cm rw
39.Op Fl f Ar device
40.Op Fl m Ar mode
41.Op Fl s Ar max-speed
42.Nm
43.Op Fl i
44.Op Fl v
45.Op Fl f Ar device
46.Nm
47.Op Fl h
48.Sh DESCRIPTION
49The
50.Nm
51utility can be used to perform raw data transfers
52.Pq read, write, or simultaneous read/write
53with devices on the SPI bus, via the
54.Xr spigen 4
55device.
56.Pp
57Each
58.Xr spigen 4
59device is associated with a specific
60.Dq chip select
61.Pq cs
62pin on the spibus, and therefore needs to be specified.
63If no device name is specified on the command line,
64.Nm
65assumes
66.Dq spigen0.0 .
67.Pp
68For more information on the spigen device, see
69.Xr spigen 4 .
70.Pp
71The options are as follows:
72.Bl -tag -width "-f device"
73.It Fl A
74Specifies ASCII mode.
75Both read and write data is input and output as
762-character hexadecimal values, optionally separated by white space,
77such as 00 01 02 etc.
78When combined with the
79.Fl b
80flag, the data on stdin remains a sequence of ASCII hexadecimal
81byte values, but the output reverts to binary mode.
82.It Fl b
83Binary
84.Pq output
85mode.
86Only has an effect when
87.Fl A
88has been specified.
89Reverts the output back to binary
90.Pq rather than ASCII ,
91while leaving the input format as-is.
92Use in combination with
93.Fl A
94to allow using something like
95.Dq echo
96to pass hexadecimal values to the SPI device, but output the received data
97on stdout as binary.
98.It Fl C Ar command-bytes
99Sends one or more command bytes,
100skipping any bytes read-in during the transfer.
101The byte values should be specified as a quoted parameter, similar to the
102format for data on stdin for
103.Fl A ,
104that is, 2 character hexadecimal values, optionally separated by white space.
105An SPI device will typically require that a command be sent, followed by
106bytes of data.
107You can use this option to send the command without receiving any data bytes
108during the command sequence.
109.It Fl c Ar count
110The total number of bytes to transfer as a decimal integer.
111If a write or a read/write transaction is being performed, and fewer than
112this number of bytes are read in from stdin, the remaining bytes will be
113sent with a value of
114.Dq 0 .
115If the length can be determined from the input file size, you can use a
116.Ar count
117value of
118.Dq -1
119to base the transfer on the input file's size.
120.It Fl d Cm r Ns | Ns Cm w Ns | Ns Cm rw
121Transfer direction: Use
122.Cm r
123for read,
124.Cm w
125for write, and
126.Cm rw
127for simultaneous read and write.
128.It Fl f Ar device
129SPI device to use
130.Pq default is Pa /dev/spigen0 .
131.It Fl h
132Print help text to stderr, explaining the command line options.
133.It Fl i
134Displays information about the SPI device to stderr.
135Whenever this flag is specified, no data is read or written, and the mode
136and clock speed are not changed.
137.It Fl L
138LSB bit order.
139The default is MSB, i.e., the highest order bit is
140transmitted first.
141Specifying
142.Fl L
143caused the LSB to be transmitted and read first.
144.It Fl m Cm 0 Ns | Ns Cm 1 Ns | Ns Cm 2 Ns | Ns Cm 3
145SPI mode, 0 through 3.
146This defines the clock phase and timing with respect to reading and writing
147data, as per the SPI specification.
148.It Fl s Ar speed
149Specify the maximum speed, in Hz, for the SPI clock.
150The bus will operate at its highest available speed which does not
151exceed this maximum.
152.It Fl v
153Specifies Verbose mode.
154Diagnostics and information are written to stderr.
155You can specify
156.Fl v
157more than once to increase verbosity.
158.El
159.Sh EXAMPLES
160Here are a few examples of using the spi utility:
161.Bl -bullet
162.It
163Get information about the default SPI device
164.Bd -literal
165spi -i
166.Ed
167.It
168Set the maximum clock speed to 200Khz and the mode to 3 on spigen0.1, but do
169not transmit nor receive any data
170.Bd -literal
171spi -f spigen0.1 -s 200000 -m 3
172.Ed
173.It
174Send a command sequence consisting of 2 bytes, and read 2 additional bytes
175from the SPI device, using the current mode and speed on the default device
176.Bd -literal
177spi -d r -C "00 01" -c 2
178.Ed
179.It
180Transmit a byte value of 5, and receive 2 bytes, displaying their values as
1812-byte ASCII hexadecimal, with mode 2, and a maximum clock speed of 500khz.
182.Bd -literal
183echo "05" | spi -A -d rw -m 2 -s 500000 -c 2
184.Ed
185.It
186Send a binary file, and output the SPI result through
187.Xr od 1
188as hexadecimal bytes, using the current maximum clock speed and SPI mode.
189.Bd -literal
190spi -d rw -c -1 <input_file.bin | od -An -t x1
191.Ed
192.It
193Send 2 bytes of data, receive a total of 4 bytes, and output the SPI result
194as binary data, piped through
195.Xr od 1 ,
196displaying it as two hexadecimal unsigned short integer values.
197.Bd -literal
198echo "00 01" | spi -A -b -d rw -c 4 | od -t x2
199.Ed
200.It
201Query the manufacturer ID and size from a standard spiflash device, by
202sending the command byte 0x9f and displaying the 3-byte reply in ASCII hex.
203.Bd -literal
204spi -f spigen0.0 -m 0 -s 1000000 -d r -c 3 -A -C 9f
205.Ed
206.El
207.Sh SEE ALSO
208.Xr spigen 4
209.Sh HISTORY
210The
211.Nm
212utility
213appeared in
214.Fx 11.3 .
215