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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 <string.h>
23 #include <glib.h>
24 #include "sigrok.h"
25 #include "sigrok-internal.h"
26 
27 struct context {
28  unsigned int num_enabled_probes;
29  unsigned int unitsize;
31  uint64_t trigger_point;
32  uint64_t samplerate;
33 };
34 
35 /**
36  * Check if the given samplerate is supported by the LA8 hardware.
37  *
38  * @param samplerate The samplerate (in Hz) to check.
39  *
40  * @return 1 if the samplerate is supported/valid, 0 otherwise.
41  */
42 static int is_valid_samplerate(uint64_t samplerate)
43 {
44  unsigned int i;
45 
46  for (i = 0; i < 255; i++) {
47  if (samplerate == (SR_MHZ(100) / (i + 1)))
48  return 1;
49  }
50 
51  sr_warn("la8 out: %s: invalid samplerate (%" PRIu64 "Hz)",
52  __func__, samplerate);
53 
54  return 0;
55 }
56 
57 /**
58  * Convert a samplerate (in Hz) to the 'divcount' value the LA8 wants.
59  *
60  * LA8 hardware: sample period = (divcount + 1) * 10ns.
61  * Min. value for divcount: 0x00 (10ns sample period, 100MHz samplerate).
62  * Max. value for divcount: 0xfe (2550ns sample period, 392.15kHz samplerate).
63  *
64  * @param samplerate The samplerate in Hz.
65  *
66  * @return The divcount value as needed by the hardware, or 0xff upon errors.
67  */
68 static uint8_t samplerate_to_divcount(uint64_t samplerate)
69 {
70  if (samplerate == 0) {
71  sr_warn("la8 out: %s: samplerate was 0", __func__);
72  return 0xff;
73  }
74 
75  if (!is_valid_samplerate(samplerate)) {
76  sr_warn("la8 out: %s: can't get divcount, samplerate invalid",
77  __func__);
78  return 0xff;
79  }
80 
81  return (SR_MHZ(100) / samplerate) - 1;
82 }
83 
84 static int init(struct sr_output *o)
85 {
86  struct context *ctx;
87  struct sr_probe *probe;
88  GSList *l;
89  uint64_t samplerate;
90 
91  if (!o) {
92  sr_warn("la8 out: %s: o was NULL", __func__);
93  return SR_ERR_ARG;
94  }
95 
96  if (!o->dev) {
97  sr_warn("la8 out: %s: o->dev was NULL", __func__);
98  return SR_ERR_ARG;
99  }
100 
101  if (!o->dev->driver) {
102  sr_warn("la8 out: %s: o->dev->driver was NULL", __func__);
103  return SR_ERR_ARG;
104  }
105 
106  if (!(ctx = g_try_malloc0(sizeof(struct context)))) {
107  sr_warn("la8 out: %s: ctx malloc failed", __func__);
108  return SR_ERR_MALLOC;
109  }
110 
111  o->internal = ctx;
112 
113  /* Get the probe names and the unitsize. */
114  /* TODO: Error handling. */
115  for (l = o->dev->probes; l; l = l->next) {
116  probe = l->data;
117  if (!probe->enabled)
118  continue;
119  ctx->probelist[ctx->num_enabled_probes++] = probe->name;
120  }
121  ctx->probelist[ctx->num_enabled_probes] = 0;
122  ctx->unitsize = (ctx->num_enabled_probes + 7) / 8;
123 
125  samplerate = *((uint64_t *) o->dev->driver->dev_info_get(
127  /* TODO: Error checks. */
128  } else {
129  samplerate = 0; /* TODO: Error or set some value? */
130  }
131  ctx->samplerate = samplerate;
132 
133  return 0; /* TODO: SR_OK? */
134 }
135 
136 static int event(struct sr_output *o, int event_type, uint8_t **data_out,
137  uint64_t *length_out)
138 {
139  struct context *ctx;
140  uint8_t *outbuf;
141 
142  if (!o) {
143  sr_warn("la8 out: %s: o was NULL", __func__);
144  return SR_ERR_ARG;
145  }
146 
147  if (!(ctx = o->internal)) {
148  sr_warn("la8 out: %s: o->internal was NULL", __func__);
149  return SR_ERR_ARG;
150  }
151 
152  if (!data_out) {
153  sr_warn("la8 out: %s: data_out was NULL", __func__);
154  return SR_ERR_ARG;
155  }
156 
157  switch (event_type) {
158  case SR_DF_TRIGGER:
159  sr_dbg("la8 out: %s: SR_DF_TRIGGER event", __func__);
160  /* Save the trigger point for later (SR_DF_END). */
161  ctx->trigger_point = 0; /* TODO: Store _actual_ value. */
162  break;
163  case SR_DF_END:
164  sr_dbg("la8 out: %s: SR_DF_END event", __func__);
165  if (!(outbuf = g_try_malloc(4 + 1))) {
166  sr_warn("la8 out: %s: outbuf malloc failed", __func__);
167  return SR_ERR_MALLOC;
168  }
169 
170  /* One byte for the 'divcount' value. */
171  outbuf[0] = samplerate_to_divcount(ctx->samplerate);
172  // if (outbuf[0] == 0xff) {
173  // sr_warn("la8 out: %s: invalid divcount", __func__);
174  // return SR_ERR;
175  // }
176 
177  /* Four bytes (little endian) for the trigger point. */
178  outbuf[1] = (ctx->trigger_point >> 0) & 0xff;
179  outbuf[2] = (ctx->trigger_point >> 8) & 0xff;
180  outbuf[3] = (ctx->trigger_point >> 16) & 0xff;
181  outbuf[4] = (ctx->trigger_point >> 24) & 0xff;
182 
183  *data_out = outbuf;
184  *length_out = 4 + 1;
185  g_free(o->internal);
186  o->internal = NULL;
187  break;
188  default:
189  sr_warn("la8 out: %s: unsupported event type: %d", __func__,
190  event_type);
191  *data_out = NULL;
192  *length_out = 0;
193  break;
194  }
195 
196  return SR_OK;
197 }
198 
199 static int data(struct sr_output *o, const uint8_t *data_in,
200  uint64_t length_in, uint8_t **data_out, uint64_t *length_out)
201 {
202  struct context *ctx;
203  uint8_t *outbuf;
204 
205  if (!o) {
206  sr_warn("la8 out: %s: o was NULL", __func__);
207  return SR_ERR_ARG;
208  }
209 
210  if (!(ctx = o->internal)) {
211  sr_warn("la8 out: %s: o->internal was NULL", __func__);
212  return SR_ERR_ARG;
213  }
214 
215  if (!data_in) {
216  sr_warn("la8 out: %s: data_in was NULL", __func__);
217  return SR_ERR_ARG;
218  }
219 
220  if (!(outbuf = g_try_malloc0(length_in))) {
221  sr_warn("la8 out: %s: outbuf malloc failed", __func__);
222  return SR_ERR_MALLOC;
223  }
224 
225  memcpy(outbuf, data_in, length_in);
226 
227  *data_out = outbuf;
228  *length_out = length_in;
229 
230  return SR_OK;
231 }
232 
234  .id = "chronovu-la8",
235  .description = "ChronoVu LA8",
236  .df_type = SR_DF_LOGIC,
237  .init = init,
238  .data = data,
239  .event = event,
240 };