Haijian Ma
676f8fd1e4
when unit suspend, pm_runtime_disalbe() would be called. And then dev.power.disable_depth number will +1. And its value will be -1 when pm_runtime_enable() is called. And if spi bus want to work as soon as system resume, it will call pm_runtime_get_sync(), which would check the value of disable_depth. If its value is not 0, spi operation will fail. The sequence is as following: runtime_suspend pm_runtime_disable()-> disable_depth +1 rumtime_resume pm_runtime_eanble() -> disable_depth -1 spi_sync() pm_runtime_get_sync -> check the value of disable_depth But for sometimes, spi operation will earlier than pm_runtime_enable() called. Then spi_sync() will fail duel to non-zero disable_depth value. So we add a checking logic before pm_runtime_get_sync() to make sure disable_depth is 0. (pick from https://gerrit.mot.com/#/c/1500296/) Change-Id: I69a0ee3d728ffe3c13d95208f203bd9ed22249b2 Signed-off-by: wengjun1 <wengjun1@motorola.com> Reviewed-on: https://gerrit.mot.com/1654438 SLTApproved: Slta Waiver SME-Granted: SME Approvals Granted Tested-by: Jira Key Reviewed-by: Huosheng Liao <liaohs@motorola.com> Submit-Approved: Jira Key
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.