X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=hardware%2Fcommon%2Fscpi_usbtmc.c;h=1ffc34ae9392c8826161e21e669eaef232daafeb;hb=bbabdaf1e2802aeef7d48fab4b0dc3507a69ffe9;hp=298e3ab52012a7ade0ce810658dddc3c4372c56a;hpb=3544f848e0d7f67af8e11ce7ec344b34cd797df3;p=libsigrok.git diff --git a/hardware/common/scpi_usbtmc.c b/hardware/common/scpi_usbtmc.c index 298e3ab5..1ffc34ae 100644 --- a/hardware/common/scpi_usbtmc.c +++ b/hardware/common/scpi_usbtmc.c @@ -28,9 +28,57 @@ #define LOG_PREFIX "scpi_usbtmc" -SR_PRIV int scpi_usbtmc_open(void *priv) +#define MAX_READ_LENGTH 2048 + +struct usbtmc_scpi { + struct sr_usbtmc_dev_inst *usbtmc; + char response_buffer[MAX_READ_LENGTH]; + int response_length; + int response_bytes_read; +}; + +static GSList *scpi_usbtmc_scan(struct drv_context *drvc) { - struct sr_usbtmc_dev_inst *usbtmc = priv; + GSList *resources = NULL; + GDir *dir; + const char *dev_name; + char *resource; + + (void)drvc; + + if (!(dir = g_dir_open("/sys/class/usbmisc/", 0, NULL))) + if (!(dir = g_dir_open("/sys/class/usb/", 0, NULL))) + return NULL; + while ((dev_name = g_dir_read_name(dir))) { + if (strncmp(dev_name, "usbtmc", 6)) + continue; + resource = g_strconcat("/dev/", dev_name, NULL); + resources = g_slist_append(resources, resource); + } + g_dir_close(dir); + + return resources; +} + +static int scpi_usbtmc_dev_inst_new(void *priv, struct drv_context *drvc, + const char *resource, char **params, const char *serialcomm) +{ + struct usbtmc_scpi *uscpi = priv; + + (void)drvc; + (void)params; + (void)serialcomm; + + if (!(uscpi->usbtmc = sr_usbtmc_dev_inst_new(resource))) + return SR_ERR; + + return SR_OK; +} + +static int scpi_usbtmc_open(void *priv) +{ + struct usbtmc_scpi *uscpi = priv; + struct sr_usbtmc_dev_inst *usbtmc = uscpi->usbtmc; if ((usbtmc->fd = open(usbtmc->device, O_RDWR)) < 0) return SR_ERR; @@ -38,24 +86,27 @@ SR_PRIV int scpi_usbtmc_open(void *priv) return SR_OK; } -SR_PRIV int scpi_usbtmc_source_add(void *priv, int events, int timeout, +static int scpi_usbtmc_source_add(void *priv, int events, int timeout, sr_receive_data_callback_t cb, void *cb_data) { - struct sr_usbtmc_dev_inst *usbtmc = priv; + struct usbtmc_scpi *uscpi = priv; + struct sr_usbtmc_dev_inst *usbtmc = uscpi->usbtmc; return sr_source_add(usbtmc->fd, events, timeout, cb, cb_data); } -SR_PRIV int scpi_usbtmc_source_remove(void *priv) +static int scpi_usbtmc_source_remove(void *priv) { - struct sr_usbtmc_dev_inst *usbtmc = priv; + struct usbtmc_scpi *uscpi = priv; + struct sr_usbtmc_dev_inst *usbtmc = uscpi->usbtmc; return sr_source_remove(usbtmc->fd); } -SR_PRIV int scpi_usbtmc_send(void *priv, const char *command) +static int scpi_usbtmc_send(void *priv, const char *command) { - struct sr_usbtmc_dev_inst *usbtmc = priv; + struct usbtmc_scpi *uscpi = priv; + struct sr_usbtmc_dev_inst *usbtmc = uscpi->usbtmc; int len, out; len = strlen(command); @@ -76,87 +127,101 @@ SR_PRIV int scpi_usbtmc_send(void *priv, const char *command) return SR_OK; } -SR_PRIV int scpi_usbtmc_receive(void *priv, char **scpi_response) +static int scpi_usbtmc_read_begin(void *priv) { - struct sr_usbtmc_dev_inst *usbtmc = priv; - GString *response; - char buf[256]; + struct usbtmc_scpi *uscpi = priv; + struct sr_usbtmc_dev_inst *usbtmc = uscpi->usbtmc; int len; - response = g_string_sized_new(1024); - - len = read(usbtmc->fd, buf, sizeof(buf)); + len = read(usbtmc->fd, uscpi->response_buffer, MAX_READ_LENGTH); if (len < 0) { sr_err("Read error: %s", strerror(errno)); - g_string_free(response, TRUE); return SR_ERR; } - response = g_string_append_len(response, buf, len); - - *scpi_response = response->str; - - sr_dbg("SCPI response received (length %d): '%.50s'", - response->len, response->str); + uscpi->response_length = len; + uscpi->response_bytes_read = 0; - g_string_free(response, FALSE); + sr_spew("Read %d bytes from device into buffer", len); return SR_OK; } -SR_PRIV int scpi_usbtmc_read(void *priv, char *buf, int maxlen) +static int scpi_usbtmc_read_data(void *priv, char *buf, int maxlen) { - struct sr_usbtmc_dev_inst *usbtmc = priv; - int len; + struct usbtmc_scpi *uscpi = priv; + int read_length; + + sr_spew("%d bytes requested", maxlen); + + if (uscpi->response_bytes_read == uscpi->response_length) { + sr_spew("Buffer is empty."); + if (uscpi->response_length == MAX_READ_LENGTH) { + sr_spew("Previous read was of maximum length, reading again."); + if (scpi_usbtmc_read_begin(uscpi) != SR_OK) + return SR_ERR; + } else { + return SR_ERR; + } + } - len = read(usbtmc->fd, buf, maxlen); + read_length = uscpi->response_length - uscpi->response_bytes_read; - if (len < 0) { - sr_err("Read error: %s", strerror(errno)); - return SR_ERR; - } + if (read_length > maxlen) + read_length = maxlen; - return len; -} + memcpy(buf, uscpi->response_buffer + uscpi->response_bytes_read, read_length); -SR_PRIV int scpi_usbtmc_close(void *priv) -{ - struct sr_usbtmc_dev_inst *usbtmc = priv; + uscpi->response_bytes_read += read_length; - if (close(usbtmc->fd) < 0) - return SR_ERR; + sr_spew("Returned %d bytes from buffer, %d/%d bytes of buffer now read", + read_length, uscpi->response_bytes_read, uscpi->response_length); - return SR_OK; + return read_length; } -static void scpi_usbtmc_free(void *priv) +static int scpi_usbtmc_read_complete(void *priv) { - return sr_usbtmc_dev_inst_free(priv); + struct usbtmc_scpi *uscpi = priv; + + if (uscpi->response_length == MAX_READ_LENGTH + && uscpi->response_bytes_read == uscpi->response_length) + scpi_usbtmc_read_begin(uscpi); + + return (uscpi->response_bytes_read >= uscpi->response_length); } -SR_PRIV struct sr_scpi_dev_inst *scpi_usbtmc_dev_inst_new(const char *device) +static int scpi_usbtmc_close(void *priv) { - struct sr_scpi_dev_inst *scpi; - struct sr_usbtmc_dev_inst *usbtmc; + struct usbtmc_scpi *uscpi = priv; - scpi = g_try_malloc(sizeof(struct sr_scpi_dev_inst)); + if (close(uscpi->usbtmc->fd) < 0) + return SR_ERR; - if (!(usbtmc = sr_usbtmc_dev_inst_new(device))) - { - g_free(scpi); - return NULL; - } + return SR_OK; +} - scpi->open = scpi_usbtmc_open; - scpi->source_add = scpi_usbtmc_source_add; - scpi->source_remove = scpi_usbtmc_source_remove; - scpi->send = scpi_usbtmc_send; - scpi->receive = scpi_usbtmc_receive; - scpi->read = scpi_usbtmc_read; - scpi->close = scpi_usbtmc_close; - scpi->free = scpi_usbtmc_free; - scpi->priv = usbtmc; - - return scpi; +static void scpi_usbtmc_free(void *priv) +{ + struct usbtmc_scpi *uscpi = priv; + + sr_usbtmc_dev_inst_free(uscpi->usbtmc); } + +SR_PRIV const struct sr_scpi_dev_inst scpi_usbtmc_dev = { + .name = "USBTMC", + .prefix = "/dev/usbtmc", + .priv_size = sizeof(struct usbtmc_scpi), + .scan = scpi_usbtmc_scan, + .dev_inst_new = scpi_usbtmc_dev_inst_new, + .open = scpi_usbtmc_open, + .source_add = scpi_usbtmc_source_add, + .source_remove = scpi_usbtmc_source_remove, + .send = scpi_usbtmc_send, + .read_begin = scpi_usbtmc_read_begin, + .read_data = scpi_usbtmc_read_data, + .read_complete = scpi_usbtmc_read_complete, + .close = scpi_usbtmc_close, + .free = scpi_usbtmc_free, +};