Il 11/01/21 20:14, AngeloGioacchino Del Regno ha scritto:
Il 11/01/21 14:57, Mark Brown ha scritto:
On Sat, Jan 09, 2021 at 02:29:19PM +0100, AngeloGioacchino Del Regno
wrote:
+ /* If the regulator is not enabled, this is a fake event */
+ if (!ops->is_enabled(vreg->rdev))
+ return 0;
Or handling the interrupt raced with a disable initiated from elsewhere.
Does the hardware actually have a problem with reporting spurious errors?
Sorry, I forgot to answer to this one in the previous email.
Yes, apparently the hardware has this issue: when the current draw is
very high and you disable the regulator while the attached device is
still drawing a lot of current (like on the Xperia XZ2 smartphone, but I
don't want to comment on that phone's HW quirks...) then the OCP
interrupt fires *after* disabling the LAB/IBB regulators.
This doesn't seem to happen if the current draw is low in the exact
moment the regulator gets disabled, but that's not always possible since
it depends on external HW design / board design sometimes...
+ return ret ? IRQ_NONE : IRQ_HANDLED;
Here and elsewhere please write normal conditional statements to improve
legibility.
No problem. Will do.
+ /* This function should be called only once, anyway. */
+ if (unlikely(vreg->ocp_irq_requested))
+ return 0;
If this is not a fast path it doesn't need an unlikely() annotation;
indeed it sounds more like there should be a warning printed if this
isn't supposed to be called multiple times.
That was extra-paranoid safety, looking at this one again, that should
be totally unnecessary.
I think that removing this check entirely would be just fine also
because.. anyway.. writing to these registers more than once won't do
any harm, nor break functionality: I mean, even if it happens for
whatever reason, there's *no real need* to avoid it from the hw
perspective.
+ /* IRQ polarities - LAB: trigger-low, IBB: trigger-high */
+ if (vreg->type == QCOM_LAB_TYPE) {
+ irq_flags |= IRQF_TRIGGER_LOW;
+ irq_trig_low = 1;
+ } else {
+ irq_flags |= IRQF_TRIGGER_HIGH;
+ irq_trig_low = 0;
+ }
This would be more clearly written as a switch statement.
A switch statement looked like being a bit "too much" for just two cases
where vreg->type cannot be anything else but QCOM_LAB_TYPE or
QCOM_IBB_TYPE... but okay, let's write a switch statement in place of that.
+ return devm_request_threaded_irq(vreg->dev, vreg->ocp_irq, NULL,
+ qcom_labibb_ocp_isr, irq_flags,
+ ocp_irq_name, vreg);
Are you *sure* that devm_ is appropriate here and the interrupt handler
won't attempt to use things that will be deallocated before devm gets
round to freeing the interrupt?
Yeah, I'm definitely sure.
+ if (!!(val & LABIBB_CONTROL_ENABLE)) {
The !! is redundant here and makes things less clear.
My bad, I forgot to clean this one up before sending.
@@ -166,8 +560,37 @@ static int qcom_labibb_of_parse_cb(struct
device_node *np,
struct regulator_config *config)
{
struct labibb_regulator *vreg = config->driver_data;
+ char *sc_irq_name;
I really, really wouldn't expect to see interrupts being requested in
the DT parsing callback - apart from anything else the device is going
to have the physical interrupts with or without DT binding information.
These callbacks are for regulator specific properties, not basic probing.
Just request the interrupts in the main probe function, this also means
you can avoid using all the DT specific APIs which are generally a
warning sign.
...And I even wrote a comment saying "The Short Circuit interrupt is
critical: fail if not found"!!! Whoa! That was bad.
Yeah, I'm definitely moving that to the appropriate place.
