Fork of alistair23 Linux kernel for reMarkable from https://github.com/alistair23/linux
72eceaad82
The Linux kernel regulator core implementation does not accept negative voltage values; all negative values are treated as errors. The problem with the EPDC is that the panel uses a negative voltage regulator which fails to be enabled by the regulator core. This issue has slipped up until the 4.9 rebase because the voltage range [min, max] was checked against only when min = max. This has been fixed in 4.9, resulting in errors in the VCOM regulator driver. The fix is to use the negative values when communicating with the hardware, but send only positive values to the regulator core. This patch sends the absolute value to the regulator core and transforms the received value (from the regulator core) to negative one before sending it to hardware. Fix device tree to deal with negative voltage regulator values by setting min_value = -real_max_value and vice versa. Boards affected: - imx6dl-sabresd - imx6ull-14x14-ddr3-arm2 - imx7d-12x12-lpddr3-arm2 - imx7d-sdb - imx6sll-evk - imx6sl-evk - imx6sll-lpddr3-arm2 Signed-off-by: Cristina Ciocan <cristina-mihaela.ciocan@nxp.com> [Arul: Fix merge conflicts] Signed-off-by: Arulpandiyan Vadivel <arulpandiyan_vadivel@mentor.com> [Robby: split original patch to driver and dts part. this is driver part.] Signed-off-by: Robby Cai <robby.cai@nxp.com> |
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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 | ||
| 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.