On Fri, May 21, 2021 at 11:04 AM Lee Jones <lee.jones@xxxxxxxxxx> wrote: > > On Fri, 21 May 2021, Robert Marko wrote: > > > On Thu, May 20, 2021 at 8:49 AM Lee Jones <lee.jones@xxxxxxxxxx> wrote: > > > > > > On Wed, 19 May 2021, Michael Walle wrote: > > > > > > > Hi, > > > > > > > > Am 2021-05-19 13:53, schrieb Robert Marko: > > > > > On Thu, May 6, 2021 at 6:34 PM Michael Walle <michael@xxxxxxxx> wrote: > > > > > > Am 2021-04-30 14:35, schrieb Robert Marko: > > > > > > > Delta TN48M switches have a Lattice CPLD that serves > > > > > > > multiple purposes including being a GPIO expander. > > > > > > > So lets add the MFD core driver for it. > > > > > > > > > > > > Did you have a look at mfd/simple-mfd-i2c.c? > > > > > > > > > > Yes, that was my first idea but we have a requirement to expose CPLD > > > > > information via debugfs as there are userspace applications using it. > > > > > And simple-mfd-i2c does not allow us to do so. > > > > > > > > Mh, last time Lee wasn't very fond of having a driver that just populates > > > > sub-drivers while doing almost nothing itself. See > > > > https://lore.kernel.org/lkml/20200605065709.GD3714@dell/ > > > > > > Right. I still feel that way. > > > > > > > That being said, I'd also like to expose our CPLD version, but until now > > > > haven't found a good solution. > > > > > > Why though? Does S/W *need* it? > > Because we have userspace S/W that uses it as the same CPLD is in > > multiple variants of the board but the correct board model is set during > > manufacturing and we can read it from the CPLD. > > > > We also have information about PSU1 and PSU2(Some models only) > > power good, whether they are present and some other info that I need > > to expose as these are monitored in userspace. > > > > I planned to do that via the hwmon driver but according to Guenther they > > are not hwmon attributes and I agree. > > > > Would it be possible to have a dedicated driver that would only expose > > the required information via debugfs? > > Then I could simply use the simple I2C MFD driver with only a GPIO > > driver on top of it. > > Yes, I was going to suggest that. > > It should probably live in drivers/misc. OK, that works for me. I will then rework this for v2. Regards, Robert > > -- > Lee Jones [李琼斯] > Senior Technical Lead - Developer Services > Linaro.org │ Open source software for Arm SoCs > Follow Linaro: Facebook | Twitter | Blog -- Robert Marko Staff Embedded Linux Engineer Sartura Ltd. Lendavska ulica 16a 10000 Zagreb, Croatia Email: robert.marko@xxxxxxxxxx Web: www.sartura.hr
