Function rtc_to_tm() is needed for FAT file system support even if we don't
have a real time clock. So move it from drivers/ to lib/.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Variable 'days' must be defined as signed int. Otherwise the conversion
fails for some dates, e.g. 2004-08-25. Cf function rtc_time64_to_tm() in
the Linux kernel source.
Fixes: 992c1db455 "drivers: rtc: resolve year 2038 problem in rtc_to_tm"
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Our implementation of rtc_to_tm() cannot handle dates of more than
0x7fffffff seconds after 1970-01-01.
Adopt the Linux kernel implementation.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>