mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-19 03:08:31 +00:00
258 lines
6.1 KiB
Text
258 lines
6.1 KiB
Text
=============================
|
|
RTC device subsystem analysis
|
|
=============================
|
|
|
|
Tomas Hlavacek <tmshlvck@gmail.com>
|
|
2012-03-10
|
|
|
|
I) Overview
|
|
-----------
|
|
|
|
U-Boot currently implements one common API for RTC devices. The interface
|
|
is defined in include/rtc.h and comprises of functions and structures:
|
|
|
|
struct rtc_time {
|
|
int tm_sec;
|
|
int tm_min;
|
|
int tm_hour;
|
|
int tm_mday;
|
|
int tm_mon;
|
|
int tm_year;
|
|
int tm_wday;
|
|
int tm_yday;
|
|
int tm_isdst;
|
|
};
|
|
|
|
int rtc_get (struct rtc_time *);
|
|
int rtc_set (struct rtc_time *);
|
|
void rtc_reset (void);
|
|
|
|
The functions are implemented by a proper device driver in drivers/rtc
|
|
directory and the driver to be compiled in is selected in a Makefile.
|
|
Drivers are mutually exclusive.
|
|
|
|
Drivers depends on date code in drivers/rtc/date.c and naturally on board
|
|
specific data.
|
|
|
|
II) Approach
|
|
------------
|
|
|
|
1) New API
|
|
----------
|
|
In the UDM each rtc driver would register itself by a function
|
|
|
|
int rtc_device_register(struct instance *i,
|
|
struct rtc_device_ops *o);
|
|
|
|
The structure being defined as follows:
|
|
|
|
struct rtc_device_ops {
|
|
int (*get_time)(struct instance *i, struct rtc_time *t);
|
|
int (*set_time)(struct instance *i, struct rtc_time *t);
|
|
int (*reset)(struct instance *i);
|
|
};
|
|
|
|
|
|
2) Conversion thougths
|
|
----------------------
|
|
U-Boot RTC drivers exports the same functions and therefore the conversion
|
|
of the drivers is straight-forward. There is no initialization needed.
|
|
|
|
|
|
III) Analysis of in-tree drivers
|
|
--------------------------------
|
|
|
|
1) drivers/rtc/rv3029.c
|
|
-----------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
2) drivers/rtc/s3c24x0_rtc.c
|
|
----------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
3) drivers/rtc/pt7c4338.c
|
|
-------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
4) drivers/rtc/mvrtc.c
|
|
----------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
5) drivers/rtc/ftrtc010.c
|
|
-------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
6) drivers/rtc/mpc5xxx.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
7) drivers/rtc/ds164x.c
|
|
-----------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
8) drivers/rtc/rs5c372.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
9) drivers/rtc/m41t94.c
|
|
-----------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
10) drivers/rtc/mc13xxx-rtc.c
|
|
-----------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
11) drivers/rtc/mcfrtc.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
12) drivers/rtc/davinci.c
|
|
-------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
13) drivers/rtc/rx8025.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
14) drivers/rtc/bfin_rtc.c
|
|
--------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
15) drivers/rtc/m41t62.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
16) drivers/rtc/ds1306.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
17) drivers/rtc/mpc8xx.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
18) drivers/rtc/ds3231.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
19) drivers/rtc/ds12887.c
|
|
-------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
20) drivers/rtc/ds1302.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
21) drivers/rtc/ds1374.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
22) drivers/rtc/ds174x.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
23) drivers/rtc/m41t60.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
24) drivers/rtc/m48t35ax.c
|
|
--------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
25) drivers/rtc/pl031.c
|
|
-----------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
26) drivers/rtc/x1205.c
|
|
-----------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
27) drivers/rtc/m41t11.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
28) drivers/rtc/pcf8563.c
|
|
-------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
29) drivers/rtc/mk48t59.c
|
|
-------------------------
|
|
Macros needs cleanup. Besides that the driver is standard rtc.
|
|
Simple conversion is possible.
|
|
|
|
|
|
30) drivers/rtc/mxsrtc.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
31) drivers/rtc/ds1307.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
32) drivers/rtc/ds1556.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
33) drivers/rtc/rtc4543.c
|
|
-------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
34) drivers/rtc/s3c44b0_rtc.c
|
|
-----------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
35) drivers/rtc/ds1337.c
|
|
------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
36) drivers/rtc/isl1208.c
|
|
-------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
37) drivers/rtc/max6900.c
|
|
-------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
38) drivers/rtc/mc146818.c
|
|
--------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|
|
|
|
|
|
39) drivers/rtc/at91sam9_rtt.c
|
|
------------------------------
|
|
The driver is standard rtc. Simple conversion is possible.
|