src/hardware/brymen-bm86x/protocol.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2014 Aurelien Jacobs <aurel@gnuage.org>
   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 3 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, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <config.h>
  21 #include <string.h>
  22 #include <math.h>
  23 #include "protocol.h"
  24
  25 #define USB_TIMEOUT 500
  26
  27 static const char char_map[128] = {
  28         [0x20] = '-',
  29         [0x5F] = '0',
  30         [0x50] = '1',
  31         [0x6D] = '2',
  32         [0x7C] = '3',
  33         [0x72] = '4',
  34         [0x3E] = '5',
  35         [0x3F] = '6',
  36         [0x54] = '7',
  37         [0x7F] = '8',
  38         [0x7E] = '9',
  39         [0x0F] = 'C',
  40         [0x27] = 'F',
  41         [0x0B] = 'L',
  42         [0x79] = 'd',
  43         [0x10] = 'i',
  44         [0x39] = 'o',
  45 };
  46
  47 static int brymen_bm86x_parse_digits(const unsigned char *buf, int length,
  48                                      char *str, float *floatval,
  49                                      char *temp_unit, int flag)
  50 {
  51         char c, *p = str;
  52         int i, ret;
  53
  54         if (buf[0] & flag)
  55                 *p++ = '-';
  56         for (i = 0; i < length; i++) {
  57                 if (i && i < 5 && buf[i+1] & 0x01)
  58                         *p++ = '.';
  59                 c = char_map[buf[i+1] >> 1];
  60                 if (i == 5 && (c == 'C' || c == 'F'))
  61                         *temp_unit = c;
  62                 else if (c)
  63                         *p++ = c;
  64         }
  65         *p = 0;
  66
  67         if ((ret = sr_atof_ascii(str, floatval))) {
  68                 sr_dbg("invalid float string: '%s'", str);
  69                 return ret;
  70         }
  71
  72         return SR_OK;
  73 }
  74
  75 static void brymen_bm86x_parse(unsigned char *buf, float *floatval,
  76                                struct sr_datafeed_analog_old *analog)
  77 {
  78         char str[16], temp_unit;
  79         int ret1, ret2, over_limit;
  80
  81         ret1 = brymen_bm86x_parse_digits(buf+2, 6, str, &floatval[0],
  82                                          &temp_unit, 0x80);
  83         over_limit = strstr(str, "0L") || strstr(str, "0.L");
  84         ret2 = brymen_bm86x_parse_digits(buf+9, 4, str, &floatval[1],
  85                                          &temp_unit, 0x10);
  86
  87         /* main display */
  88         if (ret1 == SR_OK || over_limit) {
  89                 /* SI unit */
  90                 if (buf[8] & 0x01) {
  91                         analog[0].mq = SR_MQ_VOLTAGE;
  92                         analog[0].unit = SR_UNIT_VOLT;
  93                         if (!strcmp(str, "diod"))
  94                                 analog[0].mqflags |= SR_MQFLAG_DIODE;
  95                 } else if (buf[14] & 0x80) {
  96                         analog[0].mq = SR_MQ_CURRENT;
  97                         analog[0].unit = SR_UNIT_AMPERE;
  98                 } else if (buf[14] & 0x20) {
  99                         analog[0].mq = SR_MQ_CAPACITANCE;
 100                         analog[0].unit = SR_UNIT_FARAD;
 101                 } else if (buf[14] & 0x10) {
 102                         analog[0].mq = SR_MQ_CONDUCTANCE;
 103                         analog[0].unit = SR_UNIT_SIEMENS;
 104                 } else if (buf[15] & 0x01) {
 105                         analog[0].mq = SR_MQ_FREQUENCY;
 106                         analog[0].unit = SR_UNIT_HERTZ;
 107                 } else if (buf[10] & 0x01) {
 108                         analog[0].mq = SR_MQ_CONTINUITY;
 109                         analog[0].unit = SR_UNIT_OHM;
 110                 } else if (buf[15] & 0x10) {
 111                         analog[0].mq = SR_MQ_RESISTANCE;
 112                         analog[0].unit = SR_UNIT_OHM;
 113                 } else if (buf[15] & 0x02) {
 114                         analog[0].mq = SR_MQ_POWER;
 115                         analog[0].unit = SR_UNIT_DECIBEL_MW;
 116                 } else if (buf[15] & 0x80) {
 117                         analog[0].mq = SR_MQ_DUTY_CYCLE;
 118                         analog[0].unit = SR_UNIT_PERCENTAGE;
 119                 } else if (buf[ 2] & 0x0A) {
 120                         analog[0].mq = SR_MQ_TEMPERATURE;
 121                         if (temp_unit == 'F')
 122                                 analog[0].unit = SR_UNIT_FAHRENHEIT;
 123                         else
 124                                 analog[0].unit = SR_UNIT_CELSIUS;
 125                 }
 126
 127                 /* when MIN MAX and AVG are displayed at the same time, remove them */
 128                 if ((buf[1] & 0xE0) == 0xE0)
 129                         buf[1] &= ~0xE0;
 130
 131                 /* AC/DC/Auto flags */
 132                 if (buf[1] & 0x10)  analog[0].mqflags |= SR_MQFLAG_DC;
 133                 if (buf[2] & 0x01)  analog[0].mqflags |= SR_MQFLAG_AC;
 134                 if (buf[1] & 0x01)  analog[0].mqflags |= SR_MQFLAG_AUTORANGE;
 135                 if (buf[1] & 0x08)  analog[0].mqflags |= SR_MQFLAG_HOLD;
 136                 if (buf[1] & 0x20)  analog[0].mqflags |= SR_MQFLAG_MAX;
 137                 if (buf[1] & 0x40)  analog[0].mqflags |= SR_MQFLAG_MIN;
 138                 if (buf[1] & 0x80)  analog[0].mqflags |= SR_MQFLAG_AVG;
 139                 if (buf[3] & 0x01)  analog[0].mqflags |= SR_MQFLAG_RELATIVE;
 140
 141                 /* when dBm is displayed, remove the m suffix so that it is
 142                    not considered as the 10e-3 SI prefix */
 143                 if (buf[15] & 0x02)
 144                         buf[15] &= ~0x04;
 145
 146                 /* SI prefix */
 147                 if (buf[14] & 0x40)  floatval[0] *= 1e-9;  /* n */
 148                 if (buf[15] & 0x08)  floatval[0] *= 1e-6;  /* µ */
 149                 if (buf[15] & 0x04)  floatval[0] *= 1e-3;  /* m */
 150                 if (buf[15] & 0x40)  floatval[0] *= 1e3;   /* k */
 151                 if (buf[15] & 0x20)  floatval[0] *= 1e6;   /* M */
 152
 153                 if (over_limit)      floatval[0] = INFINITY;
 154         }
 155
 156         /* secondary display */
 157         if (ret2 == SR_OK) {
 158                 /* SI unit */
 159                 if (buf[14] & 0x08) {
 160                         analog[1].mq = SR_MQ_VOLTAGE;
 161                         analog[1].unit = SR_UNIT_VOLT;
 162                 } else if (buf[9] & 0x04) {
 163                         analog[1].mq = SR_MQ_CURRENT;
 164                         analog[1].unit = SR_UNIT_AMPERE;
 165                 } else if (buf[9] & 0x08) {
 166                         analog[1].mq = SR_MQ_CURRENT;
 167                         analog[1].unit = SR_UNIT_PERCENTAGE;
 168                 } else if (buf[14] & 0x04) {
 169                         analog[1].mq = SR_MQ_FREQUENCY;
 170                         analog[1].unit = SR_UNIT_HERTZ;
 171                 } else if (buf[9] & 0x40) {
 172                         analog[1].mq = SR_MQ_TEMPERATURE;
 173                         if (temp_unit == 'F')
 174                                 analog[1].unit = SR_UNIT_FAHRENHEIT;
 175                         else
 176                                 analog[1].unit = SR_UNIT_CELSIUS;
 177                 }
 178
 179                 /* AC flag */
 180                 if (buf[9] & 0x20)  analog[1].mqflags |= SR_MQFLAG_AC;
 181
 182                 /* SI prefix */
 183                 if (buf[ 9] & 0x01)  floatval[1] *= 1e-6;  /* µ */
 184                 if (buf[ 9] & 0x02)  floatval[1] *= 1e-3;  /* m */
 185                 if (buf[14] & 0x02)  floatval[1] *= 1e3;   /* k */
 186                 if (buf[14] & 0x01)  floatval[1] *= 1e6;   /* M */
 187         }
 188
 189         if (buf[9] & 0x80)
 190                 sr_spew("Battery is low.");
 191 }
 192
 193 static void brymen_bm86x_handle_packet(const struct sr_dev_inst *sdi,
 194                                        unsigned char *buf)
 195 {
 196         struct dev_context *devc;
 197         struct sr_datafeed_packet packet;
 198         struct sr_datafeed_analog_old analog[2];
 199         float floatval[2];
 200
 201         devc = sdi->priv;
 202
 203         analog[0].mq = -1;
 204         analog[0].mqflags = 0;
 205
 206         analog[1].mq = -1;
 207         analog[1].mqflags = 0;
 208
 209         brymen_bm86x_parse(buf, floatval, analog);
 210
 211         if (analog[0].mq != -1) {
 212                 /* Got a measurement. */
 213                 analog[0].num_samples = 1;
 214                 analog[0].data = &floatval[0];
 215                 analog[0].channels = g_slist_append(NULL, sdi->channels->data);
 216                 packet.type = SR_DF_ANALOG_OLD;
 217                 packet.payload = &analog[0];
 218                 sr_session_send(sdi, &packet);
 219                 g_slist_free(analog[0].channels);
 220         }
 221
 222         if (analog[1].mq != -1) {
 223                 /* Got a measurement. */
 224                 analog[1].num_samples = 1;
 225                 analog[1].data = &floatval[1];
 226                 analog[1].channels = g_slist_append(NULL, sdi->channels->next->data);
 227                 packet.type = SR_DF_ANALOG_OLD;
 228                 packet.payload = &analog[1];
 229                 sr_session_send(sdi, &packet);
 230                 g_slist_free(analog[1].channels);
 231         }
 232
 233         if (analog[0].mq != -1 || analog[1].mq != -1)
 234                 devc->num_samples++;
 235 }
 236
 237 static int brymen_bm86x_send_command(const struct sr_dev_inst *sdi)
 238 {
 239         struct sr_usb_dev_inst *usb;
 240         unsigned char buf[] = { 0x00, 0x86, 0x66 };
 241         int ret;
 242
 243         usb = sdi->conn;
 244
 245         sr_dbg("Sending HID set report.");
 246         ret = libusb_control_transfer(usb->devhdl,
 247                                       LIBUSB_REQUEST_TYPE_CLASS  |
 248                                       LIBUSB_RECIPIENT_INTERFACE |
 249                                       LIBUSB_ENDPOINT_OUT,
 250                                       9,     /* bRequest: HID set_report */
 251                                       0x300, /* wValue: HID feature, report num 0 */
 252                                       0,     /* wIndex: interface 0 */
 253                                       buf, sizeof(buf), USB_TIMEOUT);
 254
 255         if (ret < 0) {
 256                 sr_err("HID feature report error: %s.", libusb_error_name(ret));
 257                 return SR_ERR;
 258         }
 259
 260         if (ret != sizeof(buf)) {
 261                 sr_err("Short packet: sent %d/%zu bytes.", ret, sizeof(buf));
 262                 return SR_ERR;
 263         }
 264
 265         return SR_OK;
 266 }
 267
 268 static int brymen_bm86x_read_interrupt(const struct sr_dev_inst *sdi)
 269 {
 270         struct dev_context *devc;
 271         struct sr_usb_dev_inst *usb;
 272         unsigned char buf[24];
 273         int ret, transferred;
 274
 275         devc = sdi->priv;
 276         usb = sdi->conn;
 277
 278         sr_dbg("Reading HID interrupt report.");
 279         /* Get data from EP1 using an interrupt transfer. */
 280         ret = libusb_interrupt_transfer(usb->devhdl,
 281                                         LIBUSB_ENDPOINT_IN | 1, /* EP1, IN */
 282                                         buf, sizeof(buf),
 283                                         &transferred, USB_TIMEOUT);
 284
 285         if (ret == LIBUSB_ERROR_TIMEOUT) {
 286                 if (++devc->interrupt_pending > 3)
 287                         devc->interrupt_pending = 0;
 288                 return SR_OK;
 289         }
 290
 291         if (ret < 0) {
 292                 sr_err("USB receive error: %s.", libusb_error_name(ret));
 293                 return SR_ERR;
 294         }
 295
 296         if (transferred != sizeof(buf)) {
 297                 sr_err("Short packet: received %d/%zu bytes.", transferred, sizeof(buf));
 298                 return SR_ERR;
 299         }
 300
 301         devc->interrupt_pending = 0;
 302         brymen_bm86x_handle_packet(sdi, buf);
 303
 304         return SR_OK;
 305 }
 306
 307 SR_PRIV int brymen_bm86x_receive_data(int fd, int revents, void *cb_data)
 308 {
 309         struct sr_dev_inst *sdi;
 310         struct dev_context *devc;
 311         int64_t time;
 312
 313         (void)fd;
 314         (void)revents;
 315
 316         if (!(sdi = cb_data))
 317                 return TRUE;
 318
 319         if (!(devc = sdi->priv))
 320                 return TRUE;
 321
 322         if (!devc->interrupt_pending) {
 323                 if (brymen_bm86x_send_command(sdi))
 324                         return FALSE;
 325                 devc->interrupt_pending = 1;
 326         }
 327
 328         if (brymen_bm86x_read_interrupt(sdi))
 329                 return FALSE;
 330
 331         if (devc->limit_samples && devc->num_samples >= devc->limit_samples) {
 332                 sr_info("Requested number of samples reached, stopping.");
 333                 sdi->driver->dev_acquisition_stop(sdi, cb_data);
 334                 return TRUE;
 335         }
 336
 337         if (devc->limit_msec) {
 338                 time = (g_get_monotonic_time() - devc->start_time) / 1000;
 339                 if (time > (int64_t)devc->limit_msec) {
 340                         sr_info("Requested time limit reached, stopping.");
 341                         sdi->driver->dev_acquisition_stop(sdi, cb_data);
 342                         return TRUE;
 343                 }
 344         }
 345
 346         return TRUE;
 347 }