include/uapi/linux/rtc.h | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
From: Hugo Villeneuve <hvilleneuve@dimonoff.com>
It is hard to decipher what the RTC BSM flags mean, so add
meaningful descriptions.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
---
include/uapi/linux/rtc.h | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/include/uapi/linux/rtc.h b/include/uapi/linux/rtc.h
index 97aca4503a6a..da65130e316d 100644
--- a/include/uapi/linux/rtc.h
+++ b/include/uapi/linux/rtc.h
@@ -141,10 +141,15 @@ struct rtc_param {
#define RTC_PARAM_CORRECTION 1
#define RTC_PARAM_BACKUP_SWITCH_MODE 2
+/* Backup switch mode */
#define RTC_BSM_DISABLED 0
-#define RTC_BSM_DIRECT 1
-#define RTC_BSM_LEVEL 2
-#define RTC_BSM_STANDBY 3
+#define RTC_BSM_DIRECT 1 /* Switch if Vbackup > Vdd */
+#define RTC_BSM_LEVEL 2 /* Switch based on a threshold, usually with an hysteresis */
+#define RTC_BSM_STANDBY 3 /*
+ * Switch if Vdd > Vbackup.
+ * Useful to ensure the RTC doesn't draw any
+ * power until the device is first powered on.
+ */
#define RTC_MAX_FREQ 8192
base-commit: 0bafe291cb429d39b5ff70bcf7b2f3ab026dcb02
--
2.39.5
On Mon, 21 Jul 2025 11:33:31 -0400
Hugo Villeneuve <hugo@hugovil.com> wrote:
> From: Hugo Villeneuve <hvilleneuve@dimonoff.com>
>
> It is hard to decipher what the RTC BSM flags mean, so add
> meaningful descriptions.
>
> Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
> ---
> include/uapi/linux/rtc.h | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/include/uapi/linux/rtc.h b/include/uapi/linux/rtc.h
> index 97aca4503a6a..da65130e316d 100644
> --- a/include/uapi/linux/rtc.h
> +++ b/include/uapi/linux/rtc.h
> @@ -141,10 +141,15 @@ struct rtc_param {
> #define RTC_PARAM_CORRECTION 1
> #define RTC_PARAM_BACKUP_SWITCH_MODE 2
>
> +/* Backup switch mode */
> #define RTC_BSM_DISABLED 0
> -#define RTC_BSM_DIRECT 1
> -#define RTC_BSM_LEVEL 2
> -#define RTC_BSM_STANDBY 3
> +#define RTC_BSM_DIRECT 1 /* Switch if Vbackup > Vdd */
> +#define RTC_BSM_LEVEL 2 /* Switch based on a threshold, usually with an hysteresis */
> +#define RTC_BSM_STANDBY 3 /*
> + * Switch if Vdd > Vbackup.
> + * Useful to ensure the RTC doesn't draw any
> + * power until the device is first powered on.
> + */
>
> #define RTC_MAX_FREQ 8192
Ping?
>
>
> base-commit: 0bafe291cb429d39b5ff70bcf7b2f3ab026dcb02
> --
> 2.39.5
>
>
--
Hugo Villeneuve
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