The modem remoteproc on older Qualcomm SoCs (e.g. MSM8916 and MSM8974) implements the BAM-DMUX protocol to allow access to the network data channels of the modem. The hardware/firmware resources required to implement the BAM-DMUX driver are described in an extra node in the device tree (with the compatible "qcom,bam-dmux"). This node logically belongs below the modem remoteproc, so that both control interfaces (rpmsg_wwan_ctrl) and network interfaces (bam_dmux) have a common parent. Unlike other child devices of the modem remoteproc, the bam-dmux device currently does not follow the state of the remoteproc (i.e. it is not added/removed when the remoteproc is started/stopped). However, this is an implementation detail of the bam_dmux driver in Linux that might change in the future. To be flexible for future changes, create a standard platform device specifically only for "qcom,bam-dmux", rather than populating all child nodes. This is also more consistent with the way the other child nodes are handled in the driver. Note: of_platform_device_create() and of_node_put() have NULL-checks internally, so there is no need to check if the "qcom,bam-dmux" node actually exists in the device tree. Signed-off-by: Stephan Gerhold <stephan@gerhold.net> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> Link: https://lore.kernel.org/r/20220228225400.146555-2-stephan@gerhold.net |
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| 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 | ||
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| 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.