mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-06 10:58:48 +09:00
a67a9be17e
This patch introduces a method to handle clk drift and compensation.
e.g:
&sai0 {
rockchip,mclk-calibrate;
clocks = <&cru MCLK_SAI0>, <&cru HCLK_SAI0>, <&cru PLL_HPLL>;
clock-names = "mclk", "hclk", "mclk_root";
};
/# amixer -c 0 controls | grep PPM
numid=1,iface=PCM,name='SAI0 PCM Clk Compensation In PPM'
/# amixer -c 0 cget numid=1
numid=1,iface=PCM,name='SAI0 PCM Clk Compensation In PPM'
; type=INTEGER,access=rw------,values=1,min=-1000,max=1000,step=1
: values=0
/# arecord -D hw:0,0 --period-size=1024 --buffer-size=4096 -r
16000 -c 2 -f s16_le /dev/zero &
/# amixer -- cset numid=1 -10
numid=1,iface=PCM,name='SAI0 PCM Clk Compensation In PPM'
; type=INTEGER,access=rw------,values=1,min=-1000,max=1000,step=1
: values=-10
/# amixer -- cset numid=1 10
numid=1,iface=PCM,name='SAI0 PCM Clk Compensation In PPM'
; type=INTEGER,access=rw------,values=1,min=-1000,max=1000,step=1
: values=10
Signed-off-by: Sugar Zhang <sugar.zhang@rock-chips.com>
Change-Id: Id4b299052651f7fd291f118edce6ac334002e100
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.