1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (C) 2004 Joerg Wunsch
5 * All Rights Reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29/*
30 * Send or receive messages over an SMBus.
31 */
32
33#include <err.h>
34#include <errno.h>
35#include <fcntl.h>
36#include <stdio.h>
37#include <stdlib.h>
38#include <string.h>
39#include <sysexits.h>
40#include <unistd.h>
41
42#include <sys/types.h>
43#include <sys/ioctl.h>
44
45#include <dev/smbus/smb.h>
46
47#include "pathnames.h"
48
49static const char *dev = PATH_DEFAULTSMBDEV;
50static const char *bytefmt = "0x%02x";
51static const char *wordfmt = "0x%04x";
52static const char *fmt;
53
54static int fd;			/* file descriptor for /dev/smbX */
55static int cflag = -1;		/* SMBus cmd */
56static int iflag = -1;		/* input data */
57static int oflag = -1;		/* output data */
58static int pflag;		/* probe bus */
59static int slave = -1;		/* slave address */
60static int wflag;		/* word IO */
61
62static unsigned char ibuf[SMB_MAXBLOCKSIZE];
63static unsigned char obuf[SMB_MAXBLOCKSIZE];
64static unsigned short oword;
65
66/*
67 * The I2C specs say that all addresses below 16 and above or equal
68 * 240 are reserved.  Address 0 is the global address, but we do not
69 * care for this detail.
70 */
71#define MIN_I2C_ADDR	16
72#define MAX_I2C_ADDR	240
73
74static int	do_io(void);
75static int	getnum(const char *s);
76static void	probe_i2c(void);
77static void	usage(void);
78
79static void
80usage(void)
81{
82	fprintf(stderr,
83		"usage: smbmsg [-f dev] -p\n"
84		"       smbmsg [-f dev] -s slave [-F fmt] [-c cmd] [-w] "
85		"[-i incnt] [-o outcnt] [outdata ...]\n");
86	exit(EX_USAGE);
87}
88
89static int
90getnum(const char *s)
91{
92	char *endp;
93	unsigned long l;
94
95	l = strtoul(s, &endp, 0);
96	if (*s != '\0' && *endp == '\0')
97		return (int)l;
98	return (-1);
99}
100
101static void
102probe_i2c(void)
103{
104	unsigned char addr;
105	int flags;
106#define IS_READABLE	1
107#define IS_WRITEABLE	2
108	struct smbcmd c;
109
110	printf("Probing for devices on %s:\n", dev);
111
112	for (addr = MIN_I2C_ADDR; addr < MAX_I2C_ADDR; addr += 2) {
113		c.slave = addr;
114		flags = 0;
115		if (ioctl(fd, SMB_RECVB, &c) != -1)
116			flags = IS_READABLE;
117		if (ioctl(fd, SMB_QUICK_WRITE, &c) != -1)
118			flags |= IS_WRITEABLE;
119		if (flags != 0) {
120			printf("Device @0x%02x: ", addr);
121			if (flags & IS_READABLE)
122				putchar('r');
123			if (flags & IS_WRITEABLE)
124				putchar('w');
125			putchar('\n');
126		}
127	}
128}
129
130static int
131do_io(void)
132{
133	struct smbcmd c;
134	int i;
135
136	c.slave = slave;
137	c.cmd = cflag;
138	c.rcount = 0;
139	c.wcount = 0;
140
141	if (fmt == NULL && iflag > 0)
142		fmt = wflag? wordfmt: bytefmt;
143
144	if (cflag == -1) {
145		/* operations that do not require a command byte */
146		if (iflag == -1 && oflag == 0)
147			/* 0 bytes output: quick write operation */
148			return (ioctl(fd, SMB_QUICK_WRITE, &c));
149		else if (iflag == 0 && oflag == -1)
150			/* 0 bytes input: quick read operation */
151			return (ioctl(fd, SMB_QUICK_READ, &c));
152		else if (iflag == 1 && oflag == -1) {
153			/* no command, 1 byte input: receive byte op. */
154			if (ioctl(fd, SMB_RECVB, &c) == -1)
155				return (-1);
156			printf(fmt, (unsigned char)c.cmd);
157			putchar('\n');
158			return (0);
159		} else if (iflag == -1 && oflag == 1) {
160			/* no command, 1 byte output: send byte op. */
161			c.cmd = obuf[0];
162			return (ioctl(fd, SMB_SENDB, &c));
163		} else
164			return (-2);
165	}
166	if (iflag == 1 && oflag == -1) {
167		/* command + 1 byte input: read byte op. */
168		if (ioctl(fd, SMB_READB, &c) == -1)
169			return (-1);
170		printf(fmt, (unsigned char)c.rdata.byte);
171		putchar('\n');
172		return (0);
173	} else if (iflag == -1 && oflag == 1) {
174		/* command + 1 byte output: write byte op. */
175		c.wdata.byte = obuf[0];
176		return (ioctl(fd, SMB_WRITEB, &c));
177	} else if (wflag && iflag == 2 && oflag == -1) {
178		/* command + 2 bytes input: read word op. */
179		if (ioctl(fd, SMB_READW, &c) == -1)
180			return (-1);
181		printf(fmt, (unsigned short)c.rdata.word);
182		putchar('\n');
183		return (0);
184	} else if (wflag && iflag == -1 && oflag == 2) {
185		/* command + 2 bytes output: write word op. */
186		c.wdata.word = oword;
187		return (ioctl(fd, SMB_WRITEW, &c));
188	} else if (wflag && iflag == 2 && oflag == 2) {
189		/*
190		 * command + 2 bytes output + 2 bytes input:
191		 * "process call" op.
192		 */
193		c.wdata.word = oword;
194		if (ioctl(fd, SMB_PCALL, &c) == -1)
195			return (-1);
196		printf(fmt, (unsigned short)c.rdata.word);
197		putchar('\n');
198		return (0);
199	} else if (iflag > 1 && oflag == -1) {
200		/* command + > 1 bytes of input: block read */
201		c.rbuf = ibuf;
202		c.rcount = iflag;
203		if (ioctl(fd, SMB_BREAD, &c) == -1)
204			return (-1);
205		for (i = 0; i < c.rcount; i++) {
206			if (i != 0)
207				putchar(' ');
208			printf(fmt, ibuf[i]);
209		}
210		putchar('\n');
211		return (0);
212	} else if (iflag == -1 && oflag > 1) {
213		/* command + > 1 bytes of output: block write */
214		c.wbuf = obuf;
215		c.wcount = oflag;
216		return (ioctl(fd, SMB_BWRITE, &c));
217	}
218
219	return (-2);
220}
221
222
223int
224main(int argc, char **argv)
225{
226	int i, n, errs = 0;
227	int savederrno;
228
229	while ((i = getopt(argc, argv, "F:c:f:i:o:ps:w")) != -1)
230		switch (i) {
231		case 'F':
232			fmt = optarg;
233			break;
234
235		case 'c':
236			if ((cflag = getnum(optarg)) == -1)
237				errx(EX_USAGE, "Invalid number: %s", optarg);
238			if (cflag < 0 || cflag >= 256)
239				errx(EX_USAGE,
240				     "CMD out of range: %d",
241				     cflag);
242			break;
243
244		case 'f':
245			dev = optarg;
246			break;
247
248		case 'i':
249			if ((iflag = getnum(optarg)) == -1)
250				errx(EX_USAGE, "Invalid number: %s", optarg);
251			if (iflag < 0 || iflag > SMB_MAXBLOCKSIZE)
252				errx(EX_USAGE,
253				     "# input bytes out of range: %d",
254				     iflag);
255			break;
256
257		case 'o':
258			if ((oflag = getnum(optarg)) == -1)
259				errx(EX_USAGE, "Invalid number: %s", optarg);
260			if (oflag < 0 || oflag > SMB_MAXBLOCKSIZE)
261				errx(EX_USAGE,
262				     "# output bytes out of range: %d",
263				     oflag);
264			break;
265
266		case 'p':
267			pflag = 1;
268			break;
269
270		case 's':
271			if ((slave = getnum(optarg)) == -1)
272				errx(EX_USAGE, "Invalid number: %s", optarg);
273
274			if (slave < MIN_I2C_ADDR || slave >= MAX_I2C_ADDR)
275				errx(EX_USAGE,
276				     "Slave address out of range: %d",
277				     slave);
278			break;
279
280		case 'w':
281			wflag = 1;
282			break;
283
284		default:
285			errs++;
286		}
287	argc -= optind;
288	argv += optind;
289	if (errs || (slave != -1 && pflag) || (slave == -1 && !pflag))
290		usage();
291	if (wflag &&
292	    !((iflag == 2 && oflag == -1) ||
293	      (iflag == -1 && oflag == 2) ||
294	      (iflag == 2 && oflag == 2)))
295		errx(EX_USAGE, "Illegal # IO bytes for word IO");
296	if (!pflag && iflag == -1 && oflag == -1)
297		errx(EX_USAGE, "Nothing to do");
298	if (pflag && (cflag != -1 || iflag != -1 || oflag != -1 || wflag != 0))
299		usage();
300	if (oflag > 0) {
301		if (oflag == 2 && wflag) {
302			if (argc == 0)
303				errx(EX_USAGE, "Too few arguments for -o count");
304			if ((n = getnum(*argv)) == -1)
305				errx(EX_USAGE, "Invalid number: %s", *argv);
306			if (n < 0 || n >= 65535)
307				errx(EX_USAGE, "Value out of range: %d", n);
308			oword = n;
309			argc--;
310			argv++;
311		} else for (i = 0; i < oflag; i++, argv++, argc--) {
312			if (argc == 0)
313				errx(EX_USAGE, "Too few arguments for -o count");
314			if ((n = getnum(*argv)) == -1)
315				errx(EX_USAGE, "Invalid number: %s", *argv);
316			if (n < 0 || n >= 256)
317				errx(EX_USAGE, "Value out of range: %d", n);
318			obuf[i] = n;
319		}
320	}
321	if (argc != 0)
322		usage();
323
324	if ((fd = open(dev, O_RDWR)) == -1)
325		err(EX_UNAVAILABLE, "Cannot open %s", dev);
326
327	i = 0;
328	if (pflag)
329		probe_i2c();
330	else
331		i = do_io();
332
333	savederrno = errno;
334	close(fd);
335	errno = savederrno;
336
337	if (i == -1)
338		err(EX_UNAVAILABLE, "Error performing SMBus IO");
339	else if (i == -2)
340		errx(EX_USAGE, "Invalid option combination");
341
342	return (0);
343}
344