hardware/common/scpi_serial.c

   1 /*
   2  * This file is part of the libsigrok project.
   3  *
   4  * Copyright (C) 2013 poljar (Damir Jelić) <poljarinho@gmail.com>
   5  * Copyright (C) 2013 Martin Ling <martin-sigrok@earth.li>
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "libsigrok.h"
  22 #include "libsigrok-internal.h"
  23
  24 #include <glib.h>
  25 #include <string.h>
  26
  27 #define LOG_PREFIX "scpi_serial"
  28
  29 #define SCPI_READ_RETRIES 100
  30 #define SCPI_READ_RETRY_TIMEOUT 10000
  31
  32 struct scpi_serial {
  33         struct sr_serial_dev_inst *serial;
  34         char last_character;
  35 };
  36
  37 static int scpi_serial_dev_inst_new(void *priv, const char *resource,
  38                 char **params, const char *serialcomm)
  39 {
  40         struct scpi_serial *sscpi = priv;
  41
  42         (void)params;
  43
  44         if (!(sscpi->serial = sr_serial_dev_inst_new(resource, serialcomm)))
  45                 return SR_ERR;
  46
  47         return SR_OK;
  48 }
  49
  50 static int scpi_serial_open(void *priv)
  51 {
  52         struct scpi_serial *sscpi = priv;
  53         struct sr_serial_dev_inst *serial = sscpi->serial;
  54
  55         if (serial_open(serial, SERIAL_RDWR | SERIAL_NONBLOCK) != SR_OK)
  56                 return SR_ERR;
  57
  58         if (serial_flush(serial) != SR_OK)
  59                 return SR_ERR;
  60
  61         return SR_OK;
  62 }
  63
  64 static int scpi_serial_source_add(void *priv, int events, int timeout,
  65                         sr_receive_data_callback_t cb, void *cb_data)
  66 {
  67         struct scpi_serial *sscpi = priv;
  68         struct sr_serial_dev_inst *serial = sscpi->serial;
  69
  70         return serial_source_add(serial, events, timeout, cb, cb_data);
  71 }
  72
  73 static int scpi_serial_source_remove(void *priv)
  74 {
  75         struct scpi_serial *sscpi = priv;
  76         struct sr_serial_dev_inst *serial = sscpi->serial;
  77
  78         return serial_source_remove(serial);
  79 }
  80
  81 static int scpi_serial_send(void *priv, const char *command)
  82 {
  83         int len, result, written;
  84         gchar *terminated_command;
  85         struct scpi_serial *sscpi = priv;
  86         struct sr_serial_dev_inst *serial = sscpi->serial;
  87
  88         terminated_command = g_strconcat(command, "\n", NULL);
  89         len = strlen(terminated_command);
  90         written = 0;
  91         while (written < len) {
  92                 result = serial_write(serial, terminated_command + written, len - written);
  93                 if (result < 0) {
  94                         sr_err("Error while sending SCPI command: '%s'.", command);
  95                         g_free(terminated_command);
  96                         return SR_ERR;
  97                 }
  98                 written += result;
  99         }
 100
 101         g_free(terminated_command);
 102
 103         sr_spew("Successfully sent SCPI command: '%s'.", command);
 104
 105         return SR_OK;
 106 }
 107
 108 static int scpi_serial_read_begin(void *priv)
 109 {
 110         struct scpi_serial *sscpi = priv;
 111
 112         sscpi->last_character = '\0';
 113
 114         return SR_OK;
 115 }
 116
 117 static int scpi_serial_read_data(void *priv, char *buf, int maxlen)
 118 {
 119         struct scpi_serial *sscpi = priv;
 120         int ret;
 121
 122         ret = serial_read(sscpi->serial, buf, maxlen);
 123
 124         if (ret < 0)
 125                 return ret;
 126
 127         if (ret > 0) {
 128                 sscpi->last_character = buf[ret - 1];
 129                 if (sscpi->last_character == '\n')
 130                         ret--;
 131         }
 132
 133         return ret;
 134 }
 135
 136 static int scpi_serial_read_complete(void *priv)
 137 {
 138         struct scpi_serial *sscpi = priv;
 139
 140         return (sscpi->last_character == '\n');
 141 }
 142
 143 static int scpi_serial_close(void *priv)
 144 {
 145         struct scpi_serial *sscpi = priv;
 146
 147         return serial_close(sscpi->serial);
 148 }
 149
 150 static void scpi_serial_free(void *priv)
 151 {
 152         struct scpi_serial *sscpi = priv;
 153
 154         sr_serial_dev_inst_free(sscpi->serial);
 155 }
 156
 157 SR_PRIV const struct sr_scpi_dev_inst scpi_serial_dev = {
 158         .name          = "serial",
 159         .prefix        = "",
 160         .priv_size     = sizeof(struct scpi_serial),
 161         .dev_inst_new  = scpi_serial_dev_inst_new,
 162         .open          = scpi_serial_open,
 163         .source_add    = scpi_serial_source_add,
 164         .source_remove = scpi_serial_source_remove,
 165         .send          = scpi_serial_send,
 166         .read_begin    = scpi_serial_read_begin,
 167         .read_data     = scpi_serial_read_data,
 168         .read_complete = scpi_serial_read_complete,
 169         .close         = scpi_serial_close,
 170         .free          = scpi_serial_free,
 171 };