RE: [PATCH 5/5] counter: rz-mtu3-cnt: do not use struct rz_mtu3_channel's dev member

[Cosmin-Gabriel Tanislav]

> From: William Breathitt Gray <wbg@xxxxxxxxxx>
> Sent: Sunday, March 22, 2026 8:58 AM
> 
> On Fri, Jan 30, 2026 at 02:23:53PM +0200, Cosmin Tanislav wrote:
> > The counter driver can use HW channels 1 and 2, while the PWM driver can
> > use HW channels 0, 1, 2, 3, 4, 6, 7.
> >
> > The dev member is assigned both by the counter driver and the PWM driver
> > for channels 1 and 2, to their own struct device instance, overwriting
> > the previous value.
> >
> > The sub-drivers race to assign their own struct device pointer to the
> > same struct rz_mtu3_channel's dev member.
> >
> > The dev member of struct rz_mtu3_channel is used by the counter
> > sub-driver for runtime PM.
> >
> > Depending on the probe order of the counter and PWM sub-drivers, the
> > dev member may point to the wrong struct device instance, causing the
> > counter sub-driver to do runtime PM actions on the wrong device.
> >
> > To fix this, use the parent pointer of the counter, which is assigned
> > during probe to the correct struct device, not the struct device pointer
> > inside the shared struct rz_mtu3_channel.
> 
> It looks like you replace every instance of ch->dev in the file,
> except in rz_mtu3_cnt_probe where it is initially set as ch->dev = dev.
> Is that line in rz_mtu3_cnt_probe still needed, or can it now be removed
> too?

The MTU3 MFD driver still depends on struct rz_mtu3_channel::dev being
initialized for retrieving private data from the channels.

I have patches prepared to remove that dependency and removing the dev member
will come afterwards.

Thank you for applying the patches!