Linux mainline fork with MSM8998 patches | https://mainline.space | Currently supported devices:
OnePlus 5/5T, Xiaomi Mi 6, F(x)tec Pro¹ (2019 QX1000 model) & Sony Xperia XZ Premium (UNTESTED!)
ed87d33ddb
The DT2815 analog output command is 16 bits wide, consisting of the 12-bit sample value in bits 15 to 4, the channel number in bits 3 to 1, and a voltage or current selector in bit 0. Both bytes of the 16-bit command need to be written in turn to a single 8-bit data register. However, the driver currently only writes the low 8-bits. It is broken and appears to have always been broken. Electronic copies of the DT2815 User's Manual seem impossible to find online, but looking at the source code, a best guess for the sequence the driver intended to use to write the analog output command is as follows: 1. Wait for the status register to read 0x00. 2. Write the low byte of the command to the data register. 3. Wait for the status register to read 0x80. 4. Write the high byte of the command to the data register. Step 4 is missing from the driver. Add step 4 to (hopefully) fix the driver. Also add a "FIXME" comment about setting bit 0 of the low byte of the command. Supposedly, it is used to choose between voltage output and current output, but the current driver always sets it to 1. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200406142015.126982-1-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| 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.