19abfefd4c
HD-audio drivers access to the mmio registers indirectly via the corresponding bus->io_ops callbacks. This is because some platform (notably Tegra SoC) requires the word-aligned access. But it's rather a rare case, and other platforms suffer from the penalties by indirect calls unnecessarily. This patch is an attempt to optimize and cleanup for this situation. Now the special aligned access is used only when a new kconfig CONFIG_SND_HDA_ALIGNED_MMIO is set. And the HD-audio core itself provides the aligned MMIO access helpers instead of the driver side. If Kconfig isn't set (as default), the standard helpers like readl() or writel() are used directly. A couple of places in ASoC Intel drivers have the access via io_ops reg_writel(), and they are replaced with the direct writel() calls. And now with this patch, the whole bus->io_ops becomes empty, so it's dropped completely. The bus initialization functions are changed accordingly as well to drop the whole bus->io_ops. Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> |
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| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| 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.
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.