scpi_serial.c: Drop an unneeded log message.

[libsigrok.git] / src / scpi / scpi_usbtmc_libusb.c

diff --git a/src/scpi/scpi_usbtmc_libusb.c b/src/scpi/scpi_usbtmc_libusb.c
index 7e49a8a0f12b9aef7a195cb28e5da801b9c83329..dc17c8722b44c00100ffa4a700e1769bd6787205 100644 (file)
--- a/src/scpi/scpi_usbtmc_libusb.c
+++ b/src/scpi/scpi_usbtmc_libusb.c
@@ -111,6 +111,12 @@ static struct usbtmc_blacklist blacklist_remote[] = {
        ALL_ZERO
 };
 
+/* Devices that shall get reset during open(). */
+static struct usbtmc_blacklist whitelist_usb_reset[] = {
+       { 0xf4ec, 0xffff }, /* All Siglent SDS devices */
+       ALL_ZERO
+};
+
 static GSList *scpi_usbtmc_libusb_scan(struct drv_context *drvc)
 {
        struct libusb_device **devlist;
@@ -132,8 +138,9 @@ static GSList *scpi_usbtmc_libusb_scan(struct drv_context *drvc)
 
                for (confidx = 0; confidx < des.bNumConfigurations; confidx++) {
                        if ((ret = libusb_get_config_descriptor(devlist[i], confidx, &confdes)) < 0) {
-                               sr_dbg("Failed to get configuration descriptor: %s, "
-                                      "ignoring device.", libusb_error_name(ret));
+                               if (ret != LIBUSB_ERROR_NOT_FOUND)
+                                       sr_dbg("Failed to get configuration descriptor: %s, "
+                                              "ignoring device.", libusb_error_name(ret));
                                break;
                        }
                        for (intfidx = 0; intfidx < confdes->bNumInterfaces; intfidx++) {
@@ -291,6 +298,7 @@ static int scpi_usbtmc_libusb_open(struct sr_scpi_dev_inst *scpi)
        int confidx, intfidx, epidx, config = 0, current_config;
        uint8_t capabilities[24];
        int ret, found = 0;
+       int do_reset;
 
        if (usb->devhdl)
                return SR_OK;
@@ -303,8 +311,9 @@ static int scpi_usbtmc_libusb_open(struct sr_scpi_dev_inst *scpi)
 
        for (confidx = 0; confidx < des.bNumConfigurations; confidx++) {
                if ((ret = libusb_get_config_descriptor(dev, confidx, &confdes)) < 0) {
-                       sr_dbg("Failed to get configuration descriptor: %s, "
-                              "ignoring device.", libusb_error_name(ret));
+                       if (ret != LIBUSB_ERROR_NOT_FOUND)
+                               sr_dbg("Failed to get configuration descriptor: %s, "
+                                      "ignoring device.", libusb_error_name(ret));
                        continue;
                }
                for (intfidx = 0; intfidx < confdes->bNumInterfaces; intfidx++) {
@@ -371,7 +380,11 @@ static int scpi_usbtmc_libusb_open(struct sr_scpi_dev_inst *scpi)
                return SR_ERR;
        }
 
-       libusb_reset_device(usb->devhdl);
+       /* Optionally reset the USB device. */
+       do_reset = check_usbtmc_blacklist(whitelist_usb_reset,
+               des.idVendor, des.idProduct);
+       if (do_reset)
+               libusb_reset_device(usb->devhdl);
 
        /* Get capabilities. */
        ret = libusb_control_transfer(usb->devhdl, LIBUSB_ENDPOINT_IN |