Re: [PATCH v2 15/15] drivers: thermal: tsens: Add interrupt support

From: Amit Kucheria <amit.kucheria@linaro.org>
To: Thara Gopinath <thara.gopinath@linaro.org>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-arm-msm <linux-arm-msm@vger.kernel.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Eduardo Valentin <edubezval@gmail.com>,
	Andy Gross <agross@kernel.org>, Stephen Boyd <sboyd@kernel.org>,
	Brian Masney <masneyb@onstation.org>,
	Marc Gonzalez <marc.w.gonzalez@free.fr>,
	Daniel Lezcano <daniel.lezcano@linaro.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Rob Herring <robh+dt@kernel.org>, Zhang Rui <rui.zhang@intel.com>,
	Linux PM list <linux-pm@vger.kernel.org>
Subject: Re: [PATCH v2 15/15] drivers: thermal: tsens: Add interrupt support
Date: Tue, 10 Sep 2019 21:31:38 +0530	[thread overview]
Message-ID: <CAP245DWkd4RvH1y1E17sCEndNY=xs+69EJ-41ecRL_EE0Vnkug@mail.gmail.com> (raw)
In-Reply-To: <5D674C35.6060001@linaro.org>

Hi Thara,

Thanks for the review. Please find replies below.

On Thu, Aug 29, 2019 at 9:23 AM Thara Gopinath
<thara.gopinath@linaro.org> wrote:
>
> Hi Amit,
>
> On 08/27/2019 08:14 AM, Amit Kucheria wrote:
> > Depending on the IP version, TSENS supports upper, lower, max, min and
> > critical threshold interrupts. We only add support for upper and lower
> > threshold interrupts for now.
> >
> > TSENSv2 has an irq [status|clear|mask] bit tuple for each sensor while
> > earlier versions only have a single bit per sensor to denote status and
> > clear. At each interrupt, we reprogram the new upper and lower threshold
> > in the .set_trip callback.
> >
> > Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
> > ---
> >  drivers/thermal/qcom/tsens-common.c | 377 ++++++++++++++++++++++++++--
> >  drivers/thermal/qcom/tsens-v0_1.c   |  11 +
> >  drivers/thermal/qcom/tsens-v1.c     |  29 +++
> >  drivers/thermal/qcom/tsens-v2.c     |  13 +
> >  drivers/thermal/qcom/tsens.c        |  32 ++-
> >  drivers/thermal/qcom/tsens.h        | 270 ++++++++++++++++----
> >  6 files changed, 669 insertions(+), 63 deletions(-)
> >
> > diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
> > index 06b44cfd5eab9..c549f8e1488ba 100644
> > --- a/drivers/thermal/qcom/tsens-common.c
> > +++ b/drivers/thermal/qcom/tsens-common.c

<snip>

Please snip liberally when only replying to a small part of the patch. :-)

> > +
> > +             spin_unlock_irqrestore(&priv->ul_lock, flags);
> > +
> > +             if (trigger) {
> > +                     dev_dbg(priv->dev, "[%u] %s: TZ update trigger (%d mC)\n",
> > +                             hw_id, __func__, temp);
> > +                     thermal_zone_device_update(priv->sensor[i].tzd,
> > +                                                THERMAL_EVENT_UNSPECIFIED);
> Why not use thermal_notify_framework? Or do you want to loop over all
> registered trips ?

Mainly so we get a driver call-back to set_trips where we might want
to change behaviour once we cross certain thresholds.

> Another comment I have is regarding support for multiple thermal zone.
> It might not be needed now, but presence of the same sensor can serve
> multiple zones (one for cooling and one for warming) . I am not sure if
> you want to put some infrastructure in place for that as well for
> interrupt handling.

It is premature to add such infrastructure to the driver until we
decide how we're going to implement support for this, IMO.

<snip>