mainlining shenanigans
b2bd75f806
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> Link: https://lore.kernel.org/r/20191212014507.28050-5-pierre-louis.bossart@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.