RFC: hwclock-rtc: add RTC_PARAM_BATTERY_LOW_DETECT support - #4513
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RFC: hwclock-rtc: add RTC_PARAM_BATTERY_LOW_DETECT support#4513KarlK90 wants to merge 2 commits into
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KarlK90
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| # define RTC_PARAM_CORRECTION 1 | ||
| # define RTC_PARAM_BACKUP_SWITCH_MODE 2 | ||
| # define RTC_PARAM_BATTERY_LOW_DETECT 3 | ||
| #endif /* RTC_PARAM_GET */ |
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You cannot define it in the ifndef RTC_PARAM_GET block, do it later
#if defined(RTC_PARAM_GET) && !defined(RTC_PARAM_BATTERY_LOW_DETECT)
# define RTC_PARAM_BATTERY_LOW_DETECT 3
#endif
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Done. But won't that result in compilation error in the case that RTC_PARAM_GET is undefined?
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Good point, RTC_PARAM_GET is required, but the code in this case is not strict enough. I'll improve it.
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f089382 should make RTC_PARAM_GET use more robust.
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Thanks! I have cherry-picked your commit and updated my commit on top of it.
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Replace broad #ifndef __GNU__ guards with feature-specific #ifdef RTC_PARAM_GET and #ifdef RTC_VL_READ to guard the code that depends on these ioctls. Move the fallback definitions for RTC_PARAM_GET, RTC_PARAM_SET, RTC_VL_READ, and RTC_VL_CLR from hwclock-rtc.c to hwclock.h under feature macros consistently. Signed-off-by: Karel Zak <kzak@redhat.com>
Some rtcs like the pcf2131 do not enable low battery detection by default. A new linux patch series[1] exposes a parameter to enable the detection, support is implemented in this commit. [1]: https://lore.kernel.org/all/20260311200237.3531981-1-hugo@hugovil.com/ Signed-off-by: Stefan Kerkmann <s.kerkmann@pengutronix.de>
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Draft PR - depends on pending linux patch series
Some rtcs like the pcf2131 do not enable low battery detection by default. A new linux patch series1 exposes a parameter to enable the detection, support is implemented in this commit.