When FUNCTIONFS_EVENTFD flag is set, __ffs_data_got_descs reads a 32bits, little-endian value right after the fixed structure header, and passes it to eventfd_ctx_fdget. Document this. Also, rephrase a comment to be affirmative about the role of string descriptor at index 0. Ref: USB 2.0 spec paragraph "9.6.7 String", and also checked to still be current in USB 3.0 spec paragraph "9.6.9 String".
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| @@ -93,6 +93,7 @@ struct usb_ext_prop_desc { · 92 unmodified lines | ||
| 93 | 93 | * | 0 | magic | LE32 | FUNCTIONFS_DESCRIPTORS_MAGIC_V2 | |
| 94 | 94 | * | 4 | length | LE32 | length of the whole data chunk | |
| 95 | 95 | * | 8 | flags | LE32 | combination of functionfs_flags | |
| 96 | + * | | eventfd | LE32 | eventfd file descriptor | | |
| 96 | 97 | * | | fs_count | LE32 | number of full-speed descriptors | |
| 97 | 98 | * | | hs_count | LE32 | number of high-speed descriptors | |
| 98 | 99 | * | | ss_count | LE32 | number of super-speed descriptors | |