535ba90472
Nothing prevents I2C clients to access I2C while Tegra's driver is being suspended, this results in -EBUSY error returned to the clients and that may have unfortunate consequences. In particular this causes problems for the TPS6586x MFD driver which emits hundreds of "failed to read interrupt status" error messages on resume from suspend. This happens if TPS6586X is used to wake system from suspend by the expired RTC alarm timer because TPS6586X is an I2C device driver and its IRQ handler reads the status register while Tegra's I2C driver is suspended, i.e. just after kernel enabled IRQ's during of resume-from-suspend process. Note that the removed tegra_i2c_resume() invoked tegra_i2c_init() which performs HW reset. That seems was also not entirely correct because moving tegra_i2c_resume to an earlier stage of resume-from-suspend process causes I2C transfer to fail in the case of TPS6586X. It is fine to remove the HW-reinitialization for now because it should be only needed in a case of using lowest power-mode during suspend, which upstream kernel doesn't support. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Acked-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> |
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| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| 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 | ||
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.
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.