Date: Fri, 2 May 2008 20:14:52 +0200 (CEST) From: Stefan Richter Subject: ieee1394: reduce log noise about config ROM CRC errors This avoids redundant messages about a special and usually harmless firmware flaw. Signed-off-by: Stefan Richter --- drivers/ieee1394/csr1212.c | 32 ++++++++++++++++++++++---------- 1 file changed, 22 insertions(+), 10 deletions(-) Index: linux/drivers/ieee1394/csr1212.c =================================================================== --- linux.orig/drivers/ieee1394/csr1212.c +++ linux/drivers/ieee1394/csr1212.c @@ -1049,6 +1049,24 @@ int csr1212_read(struct csr1212_csr *csr return -ENOENT; } +/* + * Apparently there are many different wrong implementations of the CRC + * algorithm. We don't fail, we just warn... approximately once per GUID. + */ +static void +csr1212_check_crc(const u32 *buffer, size_t length, u16 crc, __be32 *guid) +{ + static u64 last_bad_eui64; + u64 eui64 = ((u64)be32_to_cpu(guid[0]) << 32) | be32_to_cpu(guid[1]); + + if (csr1212_crc16(buffer, length) == crc || + csr1212_msft_crc16(buffer, length) == crc || + eui64 == last_bad_eui64) + return; + + printk(KERN_DEBUG "ieee1394: config ROM CRC error\n"); + last_bad_eui64 = eui64; +} /* Parse a chunk of data as a Config ROM */ @@ -1092,11 +1110,8 @@ static int csr1212_parse_bus_info_block( return ret; } - /* Apparently there are many different wrong implementations of the CRC - * algorithm. We don't fail, we just warn. */ - if ((csr1212_crc16(bi->data, bi->crc_length) != bi->crc) && - (csr1212_msft_crc16(bi->data, bi->crc_length) != bi->crc)) - printk(KERN_DEBUG "IEEE 1394 device has ROM CRC error\n"); + csr1212_check_crc(bi->data, bi->crc_length, bi->crc, + &csr->bus_info_data[3]); cr = CSR1212_MALLOC(sizeof(*cr)); if (!cr) @@ -1205,11 +1220,8 @@ int csr1212_parse_keyval(struct csr1212_ &cache->data[bytes_to_quads(kv->offset - cache->offset)]; kvi_len = be16_to_cpu(kvi->length); - /* Apparently there are many different wrong implementations of the CRC - * algorithm. We don't fail, we just warn. */ - if ((csr1212_crc16(kvi->data, kvi_len) != kvi->crc) && - (csr1212_msft_crc16(kvi->data, kvi_len) != kvi->crc)) - printk(KERN_DEBUG "IEEE 1394 device has ROM CRC error\n"); + /* GUID is wrong in here in case of extended ROM. We don't care. */ + csr1212_check_crc(kvi->data, kvi_len, kvi->crc, &cache->data[3]); switch (kv->key.type) { case CSR1212_KV_TYPE_DIRECTORY: