On 11-07-25, 09:24, George Verhaegen wrote:

From: Joris Verhaegen verhaegen@google.com

The current compress offload timestamping API relies on struct snd_compr_tstamp, whose cumulative counters like copied_total are defined as __u32. On long-running high-resolution audio streams, these 32-bit counters can overflow, causing incorrect availability calculations.

In your testing when did you observe the overflow condition?

This patch series introduces a parallel, 64-bit safe API to solve this problem while maintaining perfect backward compatibility with the existing UAPI. A new pointer64 operation and corresponding ioctls are added to allow the kernel to track counters using u64 and expose these full-width values to user-space.

Please share patches for tinycompress support too, we need those to test this

The series is structured as follows:

Patch 1: Introduces the new internal pointer64 op, refactors the core logic to use it, and defines the new UAPI structs.

Patch 2: Exposes the SNDRV_COMPRESS_TSTAMP64 ioctl.

Patch 3: Exposes the corresponding SNDRV_COMPRESS_AVAIL64 ioctl.

Patch 4: Implements the new .pointer64 operation in various ASoC drivers that support compress offload.

This series has been tested on a Pixel 9 device. All compress offload use cases, including long-running playback, were verified to work correctly with the new 64-bit API, and no regressions were observed when using the legacy API.

Thanks, George (Joris) Verhaegen

Signed-off-by: Joris Verhaegen verhaegen@google.com

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Joris Verhaegen (4): ALSA: compress_offload: Add 64-bit safe timestamp infrastructure ALSA: compress_offload: Add SNDRV_COMPRESS_TSTAMP64 ioctl ALSA: compress_offload: Add SNDRV_COMPRESS_AVAIL64 ioctl ASoC: codecs: Implement 64-bit pointer operation

include/sound/compress_driver.h | 3 + include/sound/soc-component.h | 5 + include/sound/soc-dai.h | 6 + include/uapi/sound/compress_offload.h | 32 +++ sound/core/compress_offload.c | 210 ++++++++++++++---- sound/soc/codecs/cs47l15.c | 1 + sound/soc/codecs/cs47l24.c | 1 + sound/soc/codecs/cs47l35.c | 1 + sound/soc/codecs/cs47l85.c | 1 + sound/soc/codecs/cs47l90.c | 1 + sound/soc/codecs/cs47l92.c | 1 + sound/soc/codecs/wm5102.c | 1 + sound/soc/codecs/wm5110.c | 1 + sound/soc/codecs/wm_adsp.c | 53 ++++- sound/soc/codecs/wm_adsp.h | 3 + .../intel/atom/sst-mfld-platform-compress.c | 17 +- sound/soc/intel/atom/sst-mfld-platform.h | 2 + sound/soc/intel/atom/sst/sst_drv_interface.c | 43 +++- sound/soc/qcom/qdsp6/q6asm-dai.c | 41 +++- sound/soc/soc-component.c | 20 ++ sound/soc/soc-compress.c | 21 ++ sound/soc/soc-dai.c | 14 ++ sound/soc/sof/compress.c | 44 +++- sound/soc/sprd/sprd-pcm-compress.c | 28 ++- sound/soc/sprd/sprd-pcm-dma.h | 2 +- sound/soc/uniphier/aio-compress.c | 40 +++- 26 files changed, 503 insertions(+), 89 deletions(-)

-- 2.50.0.727.gbf7dc18ff4-goog