From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sriram Periyasamy Subject: [RESEND][PATCH v4 0/3] Add SPIB Support for Intel Skylake platforms Date: Tue, 20 Mar 2018 21:31:05 +0530 Message-ID: <1521561668-28613-1-git-send-email-sriramx.periyasamy@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by alsa0.perex.cz (Postfix) with ESMTP id 7E7B22671F9 for ; Tue, 20 Mar 2018 17:09:32 +0100 (CET) List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: ALSA ML , Mark Brown Cc: Takashi Iwai , Sriram Periyasamy , Takashi Sakamoto , Liam Girdwood , Patches Audio , Vinod Koul List-Id: alsa-devel@alsa-project.org Skylake audio controller supports SPIB (Software Position in buffer) capability, which can be used to inform position of application pointer to host DMA controller. When SPIB mode is enabled, driver could write the application pointer position in SPIB register. Host DMA will make sure it won't read/write beyond bytes specified in SPIB register. SPIB mode will be useful in low power use cases, where DSP could pre-fetch large buffers to avoid frequent wakes caused due to interrupts. To support SPIB in the driver, save the spib values in stream context which can be restored during resume from S3. Add new hw_params flag to explicitly tell driver that rewinds will never be used. Please find the references for the previous discussions at [1][2] [1] http://mailman.alsa-project.org/pipermail/alsa-devel/2018-January/131329. html [2] https://patchwork.kernel.org/patch/9795233/ and the patches of previous versions at [3][4][5] [3] http://mailman.alsa-project.org/pipermail/alsa-devel/2017-June/121967.html [4] http://mailman.alsa-project.org/pipermail/alsa-devel/2017-June/121683.html [5] http://mailman.alsa-project.org/pipermail/alsa-devel/2017-May/120676.html Pierre-Louis Bossart (1): ALSA: core: let low-level driver or userspace disable rewinds Ramesh Babu (2): ALSA: hda: ext: add spib to stream context ASoC: Intel: Skylake: Add support for spib mode include/sound/hdaudio_ext.h | 1 + include/sound/pcm.h | 1 + include/uapi/sound/asound.h | 1 + sound/core/pcm_native.c | 8 ++++++++ sound/hda/ext/hdac_ext_stream.c | 2 ++ sound/soc/intel/skylake/skl-pcm.c | 43 ++++++++++++++++++++++++++++++++++++++- 6 files changed, 55 insertions(+), 1 deletion(-) -- 2.7.4