Re: [PATCH v3 2/2] dt-bindings: rtc: m41t80: Mark the clock: subnode as deprecated

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 12/16/22 15:24, Sebastian Reichel wrote:
Hi,

Hi,

On Thu, Dec 15, 2022 at 08:39:47PM +0100, Marek Vasut wrote:
On 12/15/22 19:06, Sebastian Reichel wrote:
On Sun, Dec 11, 2022 at 09:51:24PM +0100, Marek Vasut wrote:
The clock {} subnode seems like it is describing an always-on clock
generated by the PMIC. This should rather be modeled by consumer of
the clock taking phandle to the RTC node itself, since it already
does have clock-cells and all. Since there are no users of the clock
subnode in tree anyway, mark it as deprecated to avoid proliferation
of this approach.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
Signed-off-by: Marek Vasut <marex@xxxxxxx>
---
Cc: Alessandro Zummo <a.zummo@xxxxxxxxxxxx>
Cc: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@xxxxxxxxxx>
Cc: linux-rtc@xxxxxxxxxxxxxxx
To: devicetree@xxxxxxxxxxxxxxx
---
V2: - Add AB from Krzysztof
V3: - No change
---

I just noticed this by accident. Basically everything in the patch
description is wrong:

1. There is a in-tree user: arch/arm/boot/dts/imx6dl-qmx6.dtsi

Sorry, I missed this one.

2. The PMIC has nothing to do with this

In [3] the commit message claims the PMIC supplies 32kHz clock to i.MX6 CKIL,
which per IMX6DQRM rev.6 Table 18-3 row SNVS indirectly supplies SNVS RTC.
This reminded me of commit:

The word PMIC is not mentioned once in [3].

s@PMIC@m41t62 RTC@, sorry.

PMIC is not involved.
The QMX6 32khz chain is like this:

32kHz crystal -> m41t62 crystal input
m41t62 clock output -> i.MX6 CKIL

9509593f327ac ("arm64: dts: imx8mm: Model PMIC to SNVS RTC clock path on
Data Modul i.MX8M Mini eDM SBC")

which solves exactly the same problem, system hangs when 32 kHz clock are
stopped, except this time on i.MX8MM, clock are generated by PMIC on I2C
(notice how the PMIC is referenced directly) and the clock are supplied to
the SVNS RTC XTal terminals.

I wonder if this could be reused on the QMX6 board too?

IIRC On i.MX6 referencing the I2C connected RTC results in boot
hanging forever when trying to get the ckil clock in
imx6q_clocks_init. At least it used to be the case when I was
working on this - I no longer have access to the boards. Of course
properly referencing the RTC clock was the first route I tried.

Hmmmmm, what shall we do, un-deprecate the clock sub-node ?



[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux