ftdi-la: work around missing USB strings during device probe

[libsigrok.git] / src / hardware / ftdi-la / api.c

diff --git a/src/hardware/ftdi-la/api.c b/src/hardware/ftdi-la/api.c
index 85b7df7e383fdf4e8c396a9bae6c712a04c4ee35..8bb67121cc6c71051b279b200ffc6a6d95e2372d 100644 (file)
--- a/src/hardware/ftdi-la/api.c
+++ b/src/hardware/ftdi-la/api.c
@@ -111,6 +111,8 @@ static const struct ftdi_chip_desc *chip_descs[] = {
 static void scan_device(struct ftdi_context *ftdic,
        struct libusb_device *dev, GSList **devices)
 {
+       static const int usb_str_maxlen = 32;
+
        struct libusb_device_descriptor usb_desc;
        const struct ftdi_chip_desc *desc;
        struct dev_context *devc;
@@ -143,14 +145,42 @@ static void scan_device(struct ftdi_context *ftdic,
 
        devc->desc = desc;
 
-       vendor = g_malloc(32);
-       model = g_malloc(32);
-       serial_num = g_malloc(32);
-       rv = ftdi_usb_get_strings(ftdic, dev, vendor, 32,
-                       model, 32, serial_num, 32);
+       vendor = g_malloc(usb_str_maxlen);
+       model = g_malloc(usb_str_maxlen);
+       serial_num = g_malloc(usb_str_maxlen);
+       rv = ftdi_usb_get_strings(ftdic, dev, vendor, usb_str_maxlen,
+                       model, usb_str_maxlen, serial_num, usb_str_maxlen);
        switch (rv) {
        case 0:
                break;
+       /* ftdi_usb_get_strings() fails on first miss, hence fall through. */
+       case -7:
+               sr_dbg("The device lacks a manufacturer descriptor.");
+               g_snprintf(vendor, usb_str_maxlen, "Generic");
+               /* FALLTHROUGH */
+       case -8:
+               sr_dbg("The device lacks a product descriptor.");
+               switch (usb_desc.idProduct) {
+               case 0x6001:
+                       g_snprintf(model, usb_str_maxlen, "FT232R");
+                       break;
+               case 0x6010:
+                       g_snprintf(model, usb_str_maxlen, "FT2232H");
+                       break;
+               case 0x6011:
+                       g_snprintf(model, usb_str_maxlen, "FT4232H");
+                       break;
+               case 0x6014:
+                       g_snprintf(model, usb_str_maxlen, "FT232H");
+                       break;
+               case 0x8a98:
+                       g_snprintf(model, usb_str_maxlen, "FT2232H-TUMPA");
+                       break;
+               default:
+                       g_snprintf(model, usb_str_maxlen, "Unknown");
+                       break;
+               }
+               /* FALLTHROUGH */
        case -9:
                sr_dbg("The device lacks a serial number.");
                g_free(serial_num);