lkml.org 
[lkml]   [2018]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: omap5 fixing palmas IRQ_TYPE_NONE warning leads to gpadc timeouts
* Thierry Reding <treding@nvidia.com> [181126 10:25]:
> On Mon, Nov 26, 2018 at 11:49:54AM +0200, Peter Ujfalusi wrote:
> > The register map documentation I have states the following:
> > bit7 INT_POLARITY Select the polarity of the INT output line
> > 0: Interrupt line (INT) is low when interrupt is pending (default) RW
> > 1: Interrupt line (INT) is high when interrupt is pending
> >
> > By default the Palmas irq is active low.
>
> That would confirm that the driver code is correct. My understanding is
> that the PMC on Tegra expects a low-active IRQ from the PMIC, so we need
> to invert the interrupt again in the PMC.

But then why Tegra need to set PALMAS_POLARITY_CTRL_INT_POLARITY
if dts has IRQ_TYPE_LEVEL_HIGH? Shouldn't the Palmas default low
setting be correct for Tegra if PMC expects active-low interrupt
and then inverts it for GIC?

What seems to make most sense for me right now is either
this option A:

1. Palmas TRM has the INT_POLARITY register misdocumented
the wrong way around

2. Tegra really gets a level-low interrupt now from
Palmas with PALMAS_POLARITY_CTRL_INT_POLARITY set and
then inverts it to level-high for GIC

3. Omap5 wakeupgen does not invert the interrupt for GIC
and needs PALMAS_POLARITY_CTRL_INT_POLARITY cleared
for level-high interrupt from Palmas that gets passed
as level-high interrupt to GIC

Or else option B:

1. Palmas TRM is correct for INT_POLARITY register

2. Tegra should not set PALMAS_POLARITY_CTRL_INT_POLARITY
as Tegra PMC already translates Palmas level-low interrupt
to level-high for GIC

3. Omap5 wkupgen also translates palmas interrupt and must
not set PALMAS_POLARITY_CTRL_INT_POLARITY

Anybody got better explanations?

BTW, this interrupt is pretty easy to test with the
rtctest tool in Linux kernel:

tools/testing/selftests/rtc/rtctest.c

Regards,

Tony



\
 
 \ /
  Last update: 2018-11-26 20:32    [W:0.237 / U:0.972 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site