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chronovu_la8.c
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1 /*
2  * This file is part of the sigrok project.
3  *
4  * Copyright (C) 2011 Uwe Hermann <uwe@hermann-uwe.de>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include <stdlib.h>
22 #include <fcntl.h>
23 #include <unistd.h>
24 #include <sys/stat.h>
25 #include "sigrok.h"
26 #include "sigrok-internal.h"
27 
28 #define NUM_PACKETS 2048
29 #define PACKET_SIZE 4096
30 #define DEFAULT_NUM_PROBES 8
31 
32 /**
33  * Convert the LA8 'divcount' value to the respective samplerate (in Hz).
34  *
35  * LA8 hardware: sample period = (divcount + 1) * 10ns.
36  * Min. value for divcount: 0x00 (10ns sample period, 100MHz samplerate).
37  * Max. value for divcount: 0xfe (2550ns sample period, 392.15kHz samplerate).
38  *
39  * @param divcount The divcount value as needed by the hardware.
40  *
41  * @return The samplerate in Hz, or 0xffffffffffffffff upon errors.
42  */
43 static uint64_t divcount_to_samplerate(uint8_t divcount)
44 {
45  if (divcount == 0xff)
46  return 0xffffffffffffffffULL;
47 
48  return SR_MHZ(100) / (divcount + 1);
49 }
50 
51 static int format_match(const char *filename)
52 {
53  struct stat stat_buf;
54  int ret;
55 
56  if (!filename) {
57  sr_err("la8 in: %s: filename was NULL", __func__);
58  // return SR_ERR; /* FIXME */
59  return FALSE;
60  }
61 
62  if (!g_file_test(filename, G_FILE_TEST_EXISTS)) {
63  sr_err("la8 in: %s: input file '%s' does not exist",
64  __func__, filename);
65  // return SR_ERR; /* FIXME */
66  return FALSE;
67  }
68 
69  if (!g_file_test(filename, G_FILE_TEST_IS_REGULAR)) {
70  sr_err("la8 in: %s: input file '%s' not a regular file",
71  __func__, filename);
72  // return SR_ERR; /* FIXME */
73  return FALSE;
74  }
75 
76  /* Only accept files of length 8MB + 5 bytes. */
77  ret = stat(filename, &stat_buf);
78  if (ret != 0) {
79  sr_err("la8 in: %s: Error getting file size of '%s'",
80  __func__, filename);
81  return FALSE;
82  }
83  if (stat_buf.st_size != (8 * 1024 * 1024 + 5)) {
84  sr_dbg("la8 in: %s: File size must be exactly 8388613 bytes ("
85  "it actually is %d bytes in size), so this is not a "
86  "ChronoVu LA8 file.", __func__, stat_buf.st_size);
87  return FALSE;
88  }
89 
90  /* TODO: Check for divcount != 0xff. */
91 
92  return TRUE;
93 }
94 
95 static int init(struct sr_input *in)
96 {
97  int num_probes, i;
98  char name[SR_MAX_PROBENAME_LEN + 1];
99 
100  if (in->param && in->param[0]) {
101  num_probes = strtoul(in->param, NULL, 10);
102  if (num_probes < 1) {
103  sr_err("la8 in: %s: strtoul failed", __func__);
104  return SR_ERR;
105  }
106  } else {
107  num_probes = DEFAULT_NUM_PROBES;
108  }
109 
110  /* Create a virtual device. */
111  in->vdev = sr_dev_new(NULL, 0);
112 
113  for (i = 0; i < num_probes; i++) {
114  snprintf(name, SR_MAX_PROBENAME_LEN, "%d", i);
115  /* TODO: Check return value. */
116  sr_dev_probe_add(in->vdev, name);
117  }
118 
119  return SR_OK;
120 }
121 
122 static int loadfile(struct sr_input *in, const char *filename)
123 {
124  struct sr_datafeed_header header;
125  struct sr_datafeed_packet packet;
126  struct sr_datafeed_logic logic;
127  uint8_t buf[PACKET_SIZE], divcount;
128  int i, fd, size, num_probes;
129  uint64_t samplerate;
130 
131  /* TODO: Use glib functions! GIOChannel, g_fopen, etc. */
132  if ((fd = open(filename, O_RDONLY)) == -1) {
133  sr_err("la8 in: %s: file open failed", __func__);
134  return SR_ERR;
135  }
136 
137  num_probes = g_slist_length(in->vdev->probes);
138 
139  /* Seek to the end of the file, and read the divcount byte. */
140  divcount = 0x00; /* TODO: Don't hardcode! */
141 
142  /* Convert the divcount value to a samplerate. */
143  samplerate = divcount_to_samplerate(divcount);
144  if (samplerate == 0xffffffffffffffffULL) {
145  close(fd); /* FIXME */
146  return SR_ERR;
147  }
148  sr_dbg("la8 in: %s: samplerate is %" PRIu64, __func__, samplerate);
149 
150  /* Send header packet to the session bus. */
151  sr_dbg("la8 in: %s: sending SR_DF_HEADER packet", __func__);
152  packet.type = SR_DF_HEADER;
153  packet.payload = &header;
154  header.feed_version = 1;
155  gettimeofday(&header.starttime, NULL);
156  header.num_logic_probes = num_probes;
157  header.samplerate = samplerate;
158  sr_session_send(in->vdev, &packet);
159 
160  /* TODO: Handle trigger point. */
161 
162  /* Send data packets to the session bus. */
163  sr_dbg("la8 in: %s: sending SR_DF_LOGIC data packets", __func__);
164  packet.type = SR_DF_LOGIC;
165  packet.payload = &logic;
166  logic.unitsize = (num_probes + 7) / 8;
167  logic.data = buf;
168 
169  /* Send 8MB of total data to the session bus in small chunks. */
170  for (i = 0; i < NUM_PACKETS; i++) {
171  /* TODO: Handle errors, handle incomplete reads. */
172  size = read(fd, buf, PACKET_SIZE);
173  logic.length = size;
174  sr_session_send(in->vdev, &packet);
175  }
176  close(fd); /* FIXME */
177 
178  /* Send end packet to the session bus. */
179  sr_dbg("la8 in: %s: sending SR_DF_END", __func__);
180  packet.type = SR_DF_END;
181  packet.payload = NULL;
182  sr_session_send(in->vdev, &packet);
183 
184  return SR_OK;
185 }
186 
188  .id = "chronovu-la8",
189  .description = "ChronoVu LA8",
190  .format_match = format_match,
191  .init = init,
192  .loadfile = loadfile,
193 };