Re: [PATCH v5 03/30] thermal/core: Add a generic thermal_zone_set_trip() function

From: Daniel Lezcano
Date: Tue Sep 27 2022 - 08:21:48 EST


On 27/09/2022 12:38, Rafael J. Wysocki wrote:
On Tue, Sep 27, 2022 at 12:11 AM Daniel Lezcano
<daniel.lezcano@xxxxxxxxxx> wrote:

On 26/09/2022 21:25, Rafael J. Wysocki wrote:

[ ... ]

+ if ((t.temperature != trip->temperature) && tz->ops->set_trip_temp) {

The inner parens are not needed here and below.

+

And the extra empty line is not needed here (and below) too IMO.

+ ret = tz->ops->set_trip_temp(tz, trip_id, trip->temperature);
+ if (ret)
+ goto out;
+ }


Without the parens, the following happens:


warning: this ‘if’ clause does not guard... [-Wmisleading-indentation]
1229 | if ((t.temperature != trip->temperature) &&
tz->ops->set_trip_temp)
| ^~
note: ...this statement, but the latter is misleadingly indented as if
it were guarded by the ‘if’
1231 | if (ret)
| ^~

This is about indentation, though, so it looks like white space is
mangled somehow.

As a matter of correctness, the inner parens are not needed.

Oh, actually I did a confusion with the 'brackets', you meant:

(t.temperature != trip->temperature && tz->ops->set_trip_temp)

right ?

+ if ((t.hysteresis != trip->hysteresis) && tz->ops->set_trip_hyst) {
+
+ ret = tz->ops->set_trip_hyst(tz, trip_id, trip->hysteresis);
+ if (ret)
+ goto out;
+ }
+
+ if (((t.temperature != trip->temperature) ||
+ (t.hysteresis != trip->hysteresis)) && tz->trips)
+ tz->trips[trip_id] = *trip;

I would write this as

if (tz->trips && (t.temperature != trip->temperature || t.hysteresis
!= trip->hysteresis))
tz->trips[trip_id] = *trip;

Ok, sure

But

1. Do we want to copy the trip type here too?

The function thermal_zone_set_trip() is called from thermal_sysfs.c, it
is the unique call site. However, I think it is a good idea to check the
type of the trip point is not changed, even if it is not possible with
the actual code.

2. If tz->trips is set, do we still want to invoke ->set_trip_temp()
or ->set_trip_hyst() if they are present?

No but there are bogus drivers setting the interrupt with these ops
instead of using the set_trips ops (eg. [1][2][3]). So in order to keep
those working ATM, I'm keeping them and when all the drivers will be
changed, I'll wipe out the set_trip_* ops from everywhere.

Do those drivers set tz->trips? If not, the tz->trips check can go
before the ops ones.

Unfortunately some are doing that, like the tegra's soctherm driver


[1] drivers/thermal/samsung/exynos_tmu.c
[2] drivers/thermal/qcom/qcom-spmi-temp-alarm.c
[3] drivers/thermal/imx_thermal.c


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