Re: [PATCH v3 0/6] rtc: m41t93: add new features alarm, clock out, watchdog

[Akhilesh Patil]

On Sat, Sep 20, 2025 at 08:30:59PM +0530, Akhilesh Patil wrote:
> This patch series adds following to m41t93 rtc driver.
> 
> Functionalities: 
> - Alarm support (support to configure alarm 1)
> - Square wave output support
> - Watchdog support
> 
> Code improvements:
> this series migrates existing driver to use standard regmap interface
> for spi instead of direct spi calls and uses regmap for new features.
> 
> Device tree support:
> Adds device tree support to the driver along with binding documentation.
> 
> Testing:
> This patch series is validated on TI am62x board with m41t93 rtc chip
> connected to spi0 bus.
> regmap migration is additionally tested by observing spi transfers
> with the help of logic analyzer. Short summary of test flow is added in
> commit message of respective features.
> 
> Datasheet:
> https://www.st.com/resource/en/datasheet/m41t93.pdf
> 
> patch 4 to 6 depend on patch 3 (regmap patch)
> 
> Signed-off-by: Akhilesh Patil <akhilesh@xxxxxxxxxxxxx>
> ---

Hi Alexandre, I would like to follow-up on this patch series for review
and feedback for rtc code. Let me know if any additional improvements needed.
I am willing to volunteer to support this driver in the kernel, in case
needed, as a reviewer/maintainer. I have this m41t93 RTC hardware with
me. Given we are in 6.18 merge window, looking forward for
this patch series.

Regards,
Akhilesh

> Changes in v3:
> - Address comments on bindings from Krzysztof and add myself
> as a maintainer.
> - Re-validation/testing on top of v6.17-rc6
> - Link to v2: https://lore.kernel.org/lkml/cover.1757510157.git.akhilesh@xxxxxxxxxxxxx/
> 
> Changes in v2:
> - Address DTS and bindings coding style feedback from Krzysztof
> - Verify bindings using $ make dt_binding_check 
> - Update example in binding documentation after testing.
> - Analyze and Fix build warnings as suggested by kernel test robot.
> - Drop patch 5 from series (device detect logic change).
>   This will be taken separately. Focus on functionalities in this series.
> - Update commit messages with short test steps for each feature.
> - Link to v1: https://lore.kernel.org/lkml/cover.1756908788.git.akhilesh@xxxxxxxxxxxxx/
> ---
> 
> Akhilesh Patil (6):
>   dt-bindings: rtc: Add ST m41t93
>   rtc: m41t93: add device tree support
>   rtc: m41t93: migrate to regmap api for register access
>   rtc: m41t93: Add alarm support
>   rtc: m41t93: Add square wave clock provider support
>   rtc: m41t93: Add watchdog support
> 
>  .../devicetree/bindings/rtc/st,m41t93.yaml    |  50 ++
>  drivers/rtc/rtc-m41t93.c                      | 488 ++++++++++++++++--
>  2 files changed, 486 insertions(+), 52 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/rtc/st,m41t93.yaml
> 
> -- 
> 2.34.1
>