On Wed, Mar 14, 2018 at 2:39 PM, H. Nikolaus Schaller hns@goldelico.com wrote:
Am 13.03.2018 um 17:56 schrieb Andy Shevchenko andy.shevchenko@gmail.com: On Sat, Mar 10, 2018 at 1:00 PM, H. Nikolaus Schaller hns@goldelico.com wrote:
What does L means in the model code?
Good question. The data sheets don't tell. But 6424 and 6524 are not identical from register set and overall functions, although quite similar. Only for pin and package.
As far as I understand the 6524 (and all PCAL) have additional interrupt latch mechanisms and registers so that it is possible to disable each I/O pin individually as an interrupt while for the 6424 they are always enabled. Maybe this is the "L" designator.
IIRC "L" stands for the "Latch" as you correctly described above.
But we aren't using interrupts yet.
Are you planning? Or let's put it this way: does the hardware support it?
Perhaps we need to rename PCA_PCAL to be more specific?
My assumption is that it should be there for all PCAL variants, but I think the original author who introduced this constant should know.
The original patch was submitted by Josef Ahmad <josef.ahmad@linux.intel.com> http://git.yoctoproject.org/cgit/cgit.cgi/meta-intel-quark/tree/recipes-kernel/linux/files/0015-Quark-GPIO-1-2-quark.patch
I'm not sure we can reach to Josef (at least easily). So, better to rely on official datasheets.
{ .compatible = "nxp,pcal6524", .data = OF_953X(24, PCA_INT), },{ .compatible = "nxp,pcal9555a", .data = OF_953X(16, PCA_INT), },Other way around, you missed PCA_PCAL in the second case.
Ah, ok. It wasn't clear how these flag relate to the i2c table because they are hidden by a macro here. I'd assume that PCA_PCAL is missing for both.
Yep, if HW supports it.
So it might be that we run the pcal6524 in non-PCAL mode because we use DT. I can do a test as soon as I have access to the hardware.
Please, do.