#
936b9df7 |
|
10-May-2020 |
Gustavo A. R. Silva <gustavoars@kernel.org> |
ASoC: Intel: Skylake: Replace zero-length array with flexible-array 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 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Acked-by: Cezary Rojewski <cezary.rojewski@intel.com> Link: https://lore.kernel.org/r/20200511174647.GA17318@embeddedor Signed-off-by: Mark Brown <broonie@kernel.org>
|
#
bc2bd45b |
|
22-Nov-2017 |
Sriram Periyasamy <sriramx.periyasamy@intel.com> |
ASoC: Intel: Skylake: Parse nhlt and register clock device When NHLT endpoint is present for a SSP then we create clock for that SSP. MCLK is consistent across endpoints and configuration for an SSP, so query only for first endpoint for an SSP. For SCLK/SCLKFS, the best fit is queried from the NHLT configurations which matches the clock rate requested. Best fit is decided based on below: 1. If rate matches with multiple configurations, then the first configuration is selected. 2. If for a selected fs and bits_per_sample, there are multiple endpoint configuration match, then the configuration with max number of channels is selected. So, the user has to set the rate which fits max number of channels So we create a platform device and pass clock information parsed as platform data. Signed-off-by: Sriram Periyasamy <sriramx.periyasamy@intel.com> Signed-off-by: Jaikrishna Nemallapudi <jaikrishnax.nemallapudi@intel.com> Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
|