mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-01 09:34:10 -04:00
0196c8db83
tmio_mmc_set_clock() is full of quirks because different SoC vendors extended this in different ways. The original IP defines the divisor range 1/2 ... 1/512. bit 7 is set: 1/512 bit 6 is set: 1/256 ... bit 0 is set: 1/4 all bits clear: 1/2 It is platform-dependent how to achieve the 1/1 clock. I guess the TMIO-MFD variant uses the clock selector outside of this IP, as far as I see tmio_core_mmc_clk_div() in drivers/mfd/tmio_core.c I guess bit[7:0]=0xff is Renesas-specific extension. Socionext (and Panasonic) uses bit 10 (CLKSEL) for 1/1. Also, newer versions of UniPhier SoC variants use bit 16 for 1/1024. host->clk_update() is only used by the Renesas variants, whereas host->set_clk_div() is only used by the TMIO-MFD variants. To cope with this mess, promote tmio_mmc_set_clock() to a new platform hook ->set_clock(), and melt the old two hooks into it. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
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.