Multiple bug reports report issues with the SOF and SST drivers when
dealing with single microphone cases.
We currently read the DMIC array information unconditionally but we
don't check that the configuration type is actually a mic array.
When the DMIC link does not rely on a mic array configuration, the
recommendation is to check the format information to infer the maximum
number of channels, and map this to the number of microphones.
This leaves a potential for a mismatch between actual microphones
available in hardware and what the ACPI table contains, but we have no
other source of information.
Note that single microphone configurations can alternatively be
handled with a 'mic array' configuration along with a 'vendor-defined'
geometry.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201251
BugLink: https://github.com/thesofproject/linux/issues/2725
Fixes: 7a33ea70e1 ('ALSA: hda: intel-nhlt: handle NHLT VENDOR_DEFINED DMIC geometry')
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20210302000146.1177770-1-pierre-louis.bossart@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200507192223.GA16335@embeddedor
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The NHLT spec defines a VENDOR_DEFINED geometry, which requires
reading additional information to figure out the number of
microphones.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Move parts of the code outside of the Skylake driver to help detect
the presence of DMICs (which are not supported by the HDaudio legacy
driver).
No functionality change (except for the removal of useless OR
operations), only indentation and checkpatch fixes, making sure
that the code compiles without ACPI and fixing an ACPI leak
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Prepare move from NHLT code to common directory, starting with header.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Pierre-Louis Bossart