[alsa-devel] [PATCH] ALSA: bebob: compare whole string for model name so that readers are not confused
Takashi Sakamoto
o-takashi at sakamocchi.jp
Thu Nov 17 22:11:24 CET 2016
A modalias of 'ieee1394:ven00000D6Cmo00010060sp' hits units for M-Audio
FireWire Audiophile only. However the unit has two states relevant to
loaded firmware. Initial firmware returns 'FW Audiophile Bootloader',
while functional firmware returns 'FW Audiophile'.
ALSA bebob driver compares the units' model name to strings of 24 characters
by the first 15 characters. This is shorter way to differentiate these two
states but confusing to readers.
This commit improves the code for this point. Kernel stack is consumed more in
call of check_audiophile_booted() by a bit.
With initial firmware:
$ ./linux-firewire-utils/src/crpp < /sys/bus/firewire/devices/fw1/config_rom
ROM header and bus information block
-----------------------------------------------------------------
400 04276da6 bus_info_length 4, crc_length 39, crc 28070
404 31333934 bus_name "1394"
408 006481f2 irmc 0, cmc 0, isc 0, bmc 0, pmc 0, cyc_clk_acc 100,
max_rec 8 (512), max_rom 1, gen 15, spd 2 (S400)
40c 000d6c03 company_id 000d6c |
410 102b7e2e device_id 03102b7e2e | EUI-64 000d6c03102b7e2e
root directory
-----------------------------------------------------------------
414 00067414 directory_length 6, crc 29716
418 0c0083c0 node capabilities per IEEE 1394
41c 03000d6c vendor
420 81000009 --> descriptor leaf at 444
424 17010060 model
428 8100000c --> descriptor leaf at 458
42c d1000001 --> unit directory at 430
unit directory at 430
-----------------------------------------------------------------
430 00049da1 directory_length 4, crc 40353 (should be 48611)
434 1200a02d specifier id: 1394 TA
438 13014001 version: Vender Unique and AV/C
43c 17010060 model
440 8100000f --> descriptor leaf at 47c
descriptor leaf at 444
-----------------------------------------------------------------
444 0004073e leaf_length 4, crc 1854
448 00000000 textual descriptor
44c 00000000 minimal ASCII
450 4d2d4155 "M-AU"
454 44494f00 "DIO"
descriptor leaf at 458
-----------------------------------------------------------------
458 00086f21 leaf_length 8, crc 28449
45c 00000000 textual descriptor
460 00000000 minimal ASCII
464 46572041 "FW A"
468 7564696f "udio"
46c 7068696c "phil"
470 6520426f "e Bo"
474 6f746c6f "otlo"
478 61646572 "ader"
descriptor leaf at 47c
-----------------------------------------------------------------
47c 00086f21 leaf_length 8, crc 28449
480 00000000 textual descriptor
484 00000000 minimal ASCII
488 46572041 "FW A"
48c 7564696f "udio"
490 7068696c "phil"
494 6520426f "e Bo"
498 6f746c6f "otlo"
49c 61646572 "ader"
With functional firmware:
$ ./linux-firewire-utils/src/crpp < /sys/bus/firewire/devices/fw1/config_rom
ROM header and bus information block
-----------------------------------------------------------------
400 042de16f bus_info_length 4, crc_length 45, crc 57711
404 31333934 bus_name "1394"
408 f0648122 irmc 1, cmc 1, isc 1, bmc 1, pmc 0, cyc_clk_acc 100,
max_rec 8 (512), max_rom 1, gen 2, spd 2 (S400)
40c 000d6c03 company_id 000d6c |
410 002b7e2e device_id 03002b7e2e | EUI-64 000d6c03002b7e2e
root directory
-----------------------------------------------------------------
414 0009dac4 directory_length 9, crc 56004
418 0400000d hardware version
41c 0c0083c0 node capabilities per IEEE 1394
420 03000d6c vendor
424 81000012 --> descriptor leaf at 46c
428 17010060 model
42c 81000015 --> descriptor leaf at 480
430 13ffffff version
434 d1000002 --> unit directory at 43c
438 d4000006 --> dependent info directory at 450
unit directory at 43c
-----------------------------------------------------------------
43c 00041eb9 directory_length 4, crc 7865
440 1200a02d specifier id: 1394 TA
444 13014001 version: Vender Unique and AV/C
448 17010060 model
44c 81000014 --> descriptor leaf at 49c
dependent info directory at 450
-----------------------------------------------------------------
450 000637c7 directory_length 6, crc 14279
454 120007f5 specifier id
458 13000001 version
45c 3affffc7 (immediate value)
460 3b100000 (immediate value)
464 3cffffc7 (immediate value)
468 3d600000 (immediate value)
descriptor leaf at 46c
-----------------------------------------------------------------
46c 0004b8e4 leaf_length 4, crc 47332
470 00000000 textual descriptor
474 00000000 minimal ASCII
478 4d2d4175 "M-Au"
47c 64696f00 "dio"
descriptor leaf at 480
-----------------------------------------------------------------
480 0006194b leaf_length 6, crc 6475
484 00000000 textual descriptor
488 00000000 minimal ASCII
48c 46572041 "FW A"
490 7564696f "udio"
494 7068696c "phil"
498 65000000 "e"
descriptor leaf at 49c
-----------------------------------------------------------------
49c 0006194b leaf_length 6, crc 6475
4a0 00000000 textual descriptor
4a4 00000000 minimal ASCII
4a8 46572041 "FW A"
4ac 7564696f "udio"
4b0 7068696c "phil"
4b4 65000000 "e"
Reported-by: Nicolas Iooss <nicolas.iooss_linux at m4x.org>
Reported-by: Joe Perches <joe at perches.com>
Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
---
sound/firewire/bebob/bebob.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/sound/firewire/bebob/bebob.c b/sound/firewire/bebob/bebob.c
index 3469ac14..730ea91 100644
--- a/sound/firewire/bebob/bebob.c
+++ b/sound/firewire/bebob/bebob.c
@@ -172,12 +172,12 @@ get_saffire_spec(struct fw_unit *unit)
static bool
check_audiophile_booted(struct fw_unit *unit)
{
- char name[24] = {0};
+ char name[28] = {0};
if (fw_csr_string(unit->directory, CSR_MODEL, name, sizeof(name)) < 0)
return false;
- return strncmp(name, "FW Audiophile Bootloader", 15) != 0;
+ return strncmp(name, "FW Audiophile Bootloader", 24) != 0;
}
static void
--
2.9.3
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