From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> To: alsa-devel@alsa-project.org Cc: linux-kernel@vger.kernel.org, tiwai@suse.de, broonie@kernel.org, vkoul@kernel.org, gregkh@linuxfoundation.org, jank@cadence.com, srinivas.kandagatla@linaro.org, slawomir.blauciak@intel.com, Bard liao <yung-chuan.liao@linux.intel.com>, Rander Wang <rander.wang@linux.intel.com>, Ranjani Sridharan <ranjani.sridharan@linux.intel.com>, Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>, Sanyog Kale <sanyog.r.kale@intel.com> Subject: [PATCH v3 4/6] soundwire: sdw_slave: track unattach_request to handle all init sequences Date: Thu, 14 Nov 2019 11:53:43 -0600 [thread overview] Message-ID: <20191114175345.21836-5-pierre-louis.bossart@linux.intel.com> (raw) In-Reply-To: <20191114175345.21836-1-pierre-louis.bossart@linux.intel.com> The Slave device initialization can be split in 4 different cases: 1. Master-initiated hardware reset, system suspend-resume and pm_runtime based on clock-stop mode1. To avoid timeouts and a bad audio experience, the Slave device resume operations need to wait for the Slave device to be re-enumerated and its settings restored. 2. Exit from clock-stop mode0. In this case, the Slave device is required to remain enumerated and its context preserved while the clock is stopped, so no re-initialization or wait_for_completion() is necessary. 3. Slave-initiated pm_runtime D3 transition. With the parent child relationship, it is possible that a Slave device becomes 'suspended' while its parent is still 'active' with the bus clock still toggling. In this case, during the pm_runtime resume operation, there is no need to wait for any settings to be restored. 4. Slave reset (sync loss or implementation-defined). In that case the bus remains operational and the Slave device will be re-initialized when it becomes ATTACHED again. In previous patches, we suggested the use of wait_for_completion() to deal with the case #1, but case #2 and #3 do not need any wait. To account for those differences, this patch adds an unattach_request field. The field is explicitly set by the Master for the case #1, and if non-zero the Slave device shall wait on resume. In all other cases, the Slave resume operations can proceed without wait. The only request tracked so far is Master HardReset, but the request is declared as a bit mask for future extensions (if needed). The definition for this value is added in bus.h and does not need to be exposed in sdw.h Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> --- include/linux/soundwire/sdw.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index ed42cd79eab7..b7c9eca4332a 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -556,6 +556,11 @@ struct sdw_slave_ops { * Slave device * @initialization_complete: completion utility to control potential races * on startup between device enumeration and settings being restored + * @unattach_request: mask field to keep track why the Slave re-attached and + * was re-initialized. This is useful to deal with potential race conditions + * between the Master suspending and the codec resuming, and make sure that + * when the Master triggered a reset the Slave is properly enumerated and + * initialized */ struct sdw_slave { struct sdw_slave_id id; @@ -574,6 +579,7 @@ struct sdw_slave { struct completion probe_complete; struct completion enumeration_complete; struct completion initialization_complete; + u32 unattach_request; }; #define dev_to_sdw_dev(_dev) container_of(_dev, struct sdw_slave, dev) -- 2.20.1
WARNING: multiple messages have this Message-ID (diff)
From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> To: alsa-devel@alsa-project.org Cc: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>, tiwai@suse.de, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, Ranjani Sridharan <ranjani.sridharan@linux.intel.com>, vkoul@kernel.org, broonie@kernel.org, srinivas.kandagatla@linaro.org, jank@cadence.com, slawomir.blauciak@intel.com, Sanyog Kale <sanyog.r.kale@intel.com>, Bard liao <yung-chuan.liao@linux.intel.com>, Rander Wang <rander.wang@linux.intel.com> Subject: [alsa-devel] [PATCH v3 4/6] soundwire: sdw_slave: track unattach_request to handle all init sequences Date: Thu, 14 Nov 2019 11:53:43 -0600 [thread overview] Message-ID: <20191114175345.21836-5-pierre-louis.bossart@linux.intel.com> (raw) In-Reply-To: <20191114175345.21836-1-pierre-louis.bossart@linux.intel.com> The Slave device initialization can be split in 4 different cases: 1. Master-initiated hardware reset, system suspend-resume and pm_runtime based on clock-stop mode1. To avoid timeouts and a bad audio experience, the Slave device resume operations need to wait for the Slave device to be re-enumerated and its settings restored. 2. Exit from clock-stop mode0. In this case, the Slave device is required to remain enumerated and its context preserved while the clock is stopped, so no re-initialization or wait_for_completion() is necessary. 3. Slave-initiated pm_runtime D3 transition. With the parent child relationship, it is possible that a Slave device becomes 'suspended' while its parent is still 'active' with the bus clock still toggling. In this case, during the pm_runtime resume operation, there is no need to wait for any settings to be restored. 4. Slave reset (sync loss or implementation-defined). In that case the bus remains operational and the Slave device will be re-initialized when it becomes ATTACHED again. In previous patches, we suggested the use of wait_for_completion() to deal with the case #1, but case #2 and #3 do not need any wait. To account for those differences, this patch adds an unattach_request field. The field is explicitly set by the Master for the case #1, and if non-zero the Slave device shall wait on resume. In all other cases, the Slave resume operations can proceed without wait. The only request tracked so far is Master HardReset, but the request is declared as a bit mask for future extensions (if needed). The definition for this value is added in bus.h and does not need to be exposed in sdw.h Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> --- include/linux/soundwire/sdw.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index ed42cd79eab7..b7c9eca4332a 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -556,6 +556,11 @@ struct sdw_slave_ops { * Slave device * @initialization_complete: completion utility to control potential races * on startup between device enumeration and settings being restored + * @unattach_request: mask field to keep track why the Slave re-attached and + * was re-initialized. This is useful to deal with potential race conditions + * between the Master suspending and the codec resuming, and make sure that + * when the Master triggered a reset the Slave is properly enumerated and + * initialized */ struct sdw_slave { struct sdw_slave_id id; @@ -574,6 +579,7 @@ struct sdw_slave { struct completion probe_complete; struct completion enumeration_complete; struct completion initialization_complete; + u32 unattach_request; }; #define dev_to_sdw_dev(_dev) container_of(_dev, struct sdw_slave, dev) -- 2.20.1 _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
next prev parent reply other threads:[~2019-11-14 17:54 UTC|newest] Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-11-14 17:53 [PATCH v3 0/6] soundwire: update ASoC interfaces Pierre-Louis Bossart 2019-11-14 17:53 ` [alsa-devel] " Pierre-Louis Bossart 2019-11-14 17:53 ` [PATCH v3 1/6] soundwire: sdw_slave: add probe_complete structure and new fields Pierre-Louis Bossart 2019-11-14 17:53 ` [alsa-devel] " Pierre-Louis Bossart 2019-11-14 17:53 ` [PATCH v3 2/6] soundwire: sdw_slave: add enumeration_complete structure Pierre-Louis Bossart 2019-11-14 17:53 ` [alsa-devel] " Pierre-Louis Bossart 2019-11-14 17:53 ` [PATCH v3 3/6] soundwire: sdw_slave: add initialization_complete definition Pierre-Louis Bossart 2019-11-14 17:53 ` [alsa-devel] " Pierre-Louis Bossart 2019-11-14 17:53 ` Pierre-Louis Bossart [this message] 2019-11-14 17:53 ` [alsa-devel] [PATCH v3 4/6] soundwire: sdw_slave: track unattach_request to handle all init sequences Pierre-Louis Bossart 2019-11-14 17:53 ` [PATCH v3 5/6] soundwire: intel: update interfaces between ASoC and SoundWire Pierre-Louis Bossart 2019-11-14 17:53 ` [alsa-devel] " Pierre-Louis Bossart 2019-11-14 17:53 ` [PATCH v3 6/6] soundwire: intel: update stream callbacks for hwparams/free stream operations Pierre-Louis Bossart 2019-11-14 17:53 ` [alsa-devel] " Pierre-Louis Bossart
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20191114175345.21836-5-pierre-louis.bossart@linux.intel.com \ --to=pierre-louis.bossart@linux.intel.com \ --cc=alsa-devel@alsa-project.org \ --cc=broonie@kernel.org \ --cc=gregkh@linuxfoundation.org \ --cc=jank@cadence.com \ --cc=linux-kernel@vger.kernel.org \ --cc=rander.wang@linux.intel.com \ --cc=ranjani.sridharan@linux.intel.com \ --cc=sanyog.r.kale@intel.com \ --cc=slawomir.blauciak@intel.com \ --cc=srinivas.kandagatla@linaro.org \ --cc=tiwai@suse.de \ --cc=vkoul@kernel.org \ --cc=yung-chuan.liao@linux.intel.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.