From ac8dde11f2b397fe2282f585d5eb427a13675ea2 Mon Sep 17 00:00:00 2001 From: Michal Nazarewicz Date: Fri, 28 Feb 2014 16:50:23 +0530 Subject: [PATCH] usb: gadget: f_fs: Add flags to descriptors block This reworks the way SuperSpeed descriptors are added and instead of having a magic after full and high speed descriptors, it reworks the whole descriptors block to include a flags field which lists which descriptors are present and makes future extensions possible. Signed-off-by: Michal Nazarewicz Signed-off-by: Felipe Balbi --- drivers/usb/gadget/f_fs.c | 132 ++++++++++++---------------- drivers/usb/gadget/u_fs.h | 12 ++- include/uapi/linux/usb/functionfs.h | 49 +++++++---- 3 files changed, 91 insertions(+), 102 deletions(-) diff --git a/drivers/usb/gadget/f_fs.c b/drivers/usb/gadget/f_fs.c index 66f60b9a34a2..42f7a0e4be59 100644 --- a/drivers/usb/gadget/f_fs.c +++ b/drivers/usb/gadget/f_fs.c @@ -1434,7 +1434,7 @@ static void ffs_data_clear(struct ffs_data *ffs) if (ffs->epfiles) ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count); - kfree(ffs->raw_descs); + kfree(ffs->raw_descs_data); kfree(ffs->raw_strings); kfree(ffs->stringtabs); } @@ -1446,12 +1446,12 @@ static void ffs_data_reset(struct ffs_data *ffs) ffs_data_clear(ffs); ffs->epfiles = NULL; + ffs->raw_descs_data = NULL; ffs->raw_descs = NULL; ffs->raw_strings = NULL; ffs->stringtabs = NULL; - ffs->raw_fs_hs_descs_length = 0; - ffs->raw_ss_descs_length = 0; + ffs->raw_descs_length = 0; ffs->fs_descs_count = 0; ffs->hs_descs_count = 0; ffs->ss_descs_count = 0; @@ -1865,89 +1865,76 @@ static int __ffs_data_do_entity(enum ffs_entity_type type, static int __ffs_data_got_descs(struct ffs_data *ffs, char *const _data, size_t len) { - unsigned fs_count, hs_count, ss_count = 0; - int fs_len, hs_len, ss_len, ret = -EINVAL; - char *data = _data; + char *data = _data, *raw_descs; + unsigned counts[3], flags; + int ret = -EINVAL, i; ENTER(); - if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_DESCRIPTORS_MAGIC || - get_unaligned_le32(data + 4) != len)) + if (get_unaligned_le32(data + 4) != len) goto error; - fs_count = get_unaligned_le32(data + 8); - hs_count = get_unaligned_le32(data + 12); - - data += 16; - len -= 16; - if (likely(fs_count)) { - fs_len = ffs_do_descs(fs_count, data, len, - __ffs_data_do_entity, ffs); - if (unlikely(fs_len < 0)) { - ret = fs_len; + switch (get_unaligned_le32(data)) { + case FUNCTIONFS_DESCRIPTORS_MAGIC: + flags = FUNCTIONFS_HAS_FS_DESC | FUNCTIONFS_HAS_HS_DESC; + data += 8; + len -= 8; + break; + case FUNCTIONFS_DESCRIPTORS_MAGIC_V2: + flags = get_unaligned_le32(data + 8); + if (flags & ~(FUNCTIONFS_HAS_FS_DESC | + FUNCTIONFS_HAS_HS_DESC | + FUNCTIONFS_HAS_SS_DESC)) { + ret = -ENOSYS; goto error; } - - data += fs_len; - len -= fs_len; - } else { - fs_len = 0; + data += 12; + len -= 12; + break; + default: + goto error; } - if (likely(hs_count)) { - hs_len = ffs_do_descs(hs_count, data, len, - __ffs_data_do_entity, ffs); - if (unlikely(hs_len < 0)) { - ret = hs_len; + /* Read fs_count, hs_count and ss_count (if present) */ + for (i = 0; i < 3; ++i) { + if (!(flags & (1 << i))) { + counts[i] = 0; + } else if (len < 4) { goto error; + } else { + counts[i] = get_unaligned_le32(data); + data += 4; + len -= 4; } - - data += hs_len; - len -= hs_len; - } else { - hs_len = 0; - } - - if (len >= 8) { - /* Check SS_MAGIC for presence of ss_descs and get SS_COUNT */ - if (get_unaligned_le32(data) != FUNCTIONFS_SS_DESC_MAGIC) - goto einval; - - ss_count = get_unaligned_le32(data + 4); - data += 8; - len -= 8; } - if (!fs_count && !hs_count && !ss_count) - goto einval; - - if (ss_count) { - ss_len = ffs_do_descs(ss_count, data, len, + /* Read descriptors */ + raw_descs = data; + for (i = 0; i < 3; ++i) { + if (!counts[i]) + continue; + ret = ffs_do_descs(counts[i], data, len, __ffs_data_do_entity, ffs); - if (unlikely(ss_len < 0)) { - ret = ss_len; + if (ret < 0) goto error; - } - ret = ss_len; - } else { - ss_len = 0; - ret = 0; + data += ret; + len -= ret; } - if (unlikely(len != ret)) - goto einval; + if (raw_descs == data || len) { + ret = -EINVAL; + goto error; + } - ffs->raw_fs_hs_descs_length = fs_len + hs_len; - ffs->raw_ss_descs_length = ss_len; - ffs->raw_descs = _data; - ffs->fs_descs_count = fs_count; - ffs->hs_descs_count = hs_count; - ffs->ss_descs_count = ss_count; + ffs->raw_descs_data = _data; + ffs->raw_descs = raw_descs; + ffs->raw_descs_length = data - raw_descs; + ffs->fs_descs_count = counts[0]; + ffs->hs_descs_count = counts[1]; + ffs->ss_descs_count = counts[2]; return 0; -einval: - ret = -EINVAL; error: kfree(_data); return ret; @@ -2359,8 +2346,7 @@ static int _ffs_func_bind(struct usb_configuration *c, vla_item_with_sz(d, struct usb_descriptor_header *, ss_descs, super ? ffs->ss_descs_count + 1 : 0); vla_item_with_sz(d, short, inums, ffs->interfaces_count); - vla_item_with_sz(d, char, raw_descs, - ffs->raw_fs_hs_descs_length + ffs->raw_ss_descs_length); + vla_item_with_sz(d, char, raw_descs, ffs->raw_descs_length); char *vlabuf; ENTER(); @@ -2376,15 +2362,9 @@ static int _ffs_func_bind(struct usb_configuration *c, /* Zero */ memset(vla_ptr(vlabuf, d, eps), 0, d_eps__sz); - /* Copy only raw (hs,fs) descriptors (until ss_magic and ss_count) */ - memcpy(vla_ptr(vlabuf, d, raw_descs), ffs->raw_descs + 16, - ffs->raw_fs_hs_descs_length); - /* Copy SS descs present @ header + hs_fs_descs + ss_magic + ss_count */ - if (func->ffs->ss_descs_count) - memcpy(vla_ptr(vlabuf, d, raw_descs) + - ffs->raw_fs_hs_descs_length, - ffs->raw_descs + 16 + ffs->raw_fs_hs_descs_length + 8, - ffs->raw_ss_descs_length); + /* Copy descriptors */ + memcpy(vla_ptr(vlabuf, d, raw_descs), ffs->raw_descs, + ffs->raw_descs_length); memset(vla_ptr(vlabuf, d, inums), 0xff, d_inums__sz); for (ret = ffs->eps_count; ret; --ret) { diff --git a/drivers/usb/gadget/u_fs.h b/drivers/usb/gadget/u_fs.h index 0deb6d5f7c35..bf0ba375d459 100644 --- a/drivers/usb/gadget/u_fs.h +++ b/drivers/usb/gadget/u_fs.h @@ -206,15 +206,13 @@ struct ffs_data { /* filled by __ffs_data_got_descs() */ /* - * Real descriptors are 16 bytes after raw_descs (so you need - * to skip 16 bytes (ie. ffs->raw_descs + 16) to get to the - * first full speed descriptor). - * raw_fs_hs_descs_length does not have those 16 bytes added. - * ss_descs are 8 bytes (ss_magic + count) pass the hs_descs + * raw_descs is what you kfree, real_descs points inside of raw_descs, + * where full speed, high speed and super speed descriptors start. + * real_descs_length is the length of all those descriptors. */ + const void *raw_descs_data; const void *raw_descs; - unsigned raw_fs_hs_descs_length; - unsigned raw_ss_descs_length; + unsigned raw_descs_length; unsigned fs_descs_count; unsigned hs_descs_count; unsigned ss_descs_count; diff --git a/include/uapi/linux/usb/functionfs.h b/include/uapi/linux/usb/functionfs.h index 0f8f7be5b0d3..2a4b4a72a4f9 100644 --- a/include/uapi/linux/usb/functionfs.h +++ b/include/uapi/linux/usb/functionfs.h @@ -10,10 +10,15 @@ enum { FUNCTIONFS_DESCRIPTORS_MAGIC = 1, - FUNCTIONFS_STRINGS_MAGIC = 2 + FUNCTIONFS_STRINGS_MAGIC = 2, + FUNCTIONFS_DESCRIPTORS_MAGIC_V2 = 3, }; -#define FUNCTIONFS_SS_DESC_MAGIC 0x0055DE5C +enum functionfs_flags { + FUNCTIONFS_HAS_FS_DESC = 1, + FUNCTIONFS_HAS_HS_DESC = 2, + FUNCTIONFS_HAS_SS_DESC = 4, +}; #ifndef __KERNEL__ @@ -29,34 +34,40 @@ struct usb_endpoint_descriptor_no_audio { } __attribute__((packed)); -/* - * All numbers must be in little endian order. - */ - -struct usb_functionfs_descs_head { - __le32 magic; - __le32 length; - __le32 fs_count; - __le32 hs_count; -} __attribute__((packed)); - /* * Descriptors format: * * | off | name | type | description | * |-----+-----------+--------------+--------------------------------------| - * | 0 | magic | LE32 | FUNCTIONFS_{FS,HS}_DESCRIPTORS_MAGIC | + * | 0 | magic | LE32 | FUNCTIONFS_DESCRIPTORS_MAGIC_V2 | + * | 4 | length | LE32 | length of the whole data chunk | + * | 8 | flags | LE32 | combination of functionfs_flags | + * | | fs_count | LE32 | number of full-speed descriptors | + * | | hs_count | LE32 | number of high-speed descriptors | + * | | ss_count | LE32 | number of super-speed descriptors | + * | | fs_descrs | Descriptor[] | list of full-speed descriptors | + * | | hs_descrs | Descriptor[] | list of high-speed descriptors | + * | | ss_descrs | Descriptor[] | list of super-speed descriptors | + * + * Depending on which flags are set, various fields may be missing in the + * structure. Any flags that are not recognised cause the whole block to be + * rejected with -ENOSYS. + * + * Legacy descriptors format: + * + * | off | name | type | description | + * |-----+-----------+--------------+--------------------------------------| + * | 0 | magic | LE32 | FUNCTIONFS_DESCRIPTORS_MAGIC | * | 4 | length | LE32 | length of the whole data chunk | * | 8 | fs_count | LE32 | number of full-speed descriptors | * | 12 | hs_count | LE32 | number of high-speed descriptors | * | 16 | fs_descrs | Descriptor[] | list of full-speed descriptors | * | | hs_descrs | Descriptor[] | list of high-speed descriptors | - * | | ss_magic | LE32 | FUNCTIONFS_SS_DESC_MAGIC | - * | | ss_count | LE32 | number of super-speed descriptors | - * | | ss_descrs | Descriptor[] | list of super-speed descriptors | * - * ss_magic: if present then it implies that SS_DESCs are also present - * descs are just valid USB descriptors and have the following format: + * All numbers must be in little endian order. + * + * Descriptor[] is an array of valid USB descriptors which have the following + * format: * * | off | name | type | description | * |-----+-----------------+------+--------------------------| -- 2.39.5