On 04/04/2023 17:40, Tilki, Ibrahim wrote: >>> + interrupts: >>> + description: | >>> + Alarm1 interrupt line of the RTC. Some of the RTCs have two interrupt >>> + lines and alarm1 interrupt muxing depends on the clockin/clockout >>> + configuration. >>> + maxItems: 1 >>> + >>> + "#clock-cells": >>> + description: | >>> + RTC can be used as a clock source through its clock output pin when >>> + supplied. >> >> This part is correct, but your implementation is not. I don't think you >> can disable or enable interrupts, based on usage of clock. Either this >> is clock (gated or not) or interrupt, not both. >> > > The driver doesn't enable or disable interrupts based on clock usage. It checks > whether the IRQ is possible or not. Enablement of interrupt depends on the > "interrupts" property. The tricky part is that interrupt muxing depends on > clock configuration. I think it is not what your driver is doing. It checks if clock-cells... > > Let me briefly explain the behavior of RTCs and the driver[v4] > > MAX31328: > - Has a single pin which is either used as IRQ or clock output. > - Driver aborts probe with "-EOPNOTSUPP" when user requests irq and clockout > at the same time. In other words, when both "interrupts" and "#clock-cells" > properties are present. Otherwise, we are fine. Why? These are fixed properties of the device. It is always a clock controller and always has interrupt line. The choice between them is depending on pins, so pin control. > > MAX31331: > MAX31334: > - Has two pins: INTA and INTB/CLOCKOUT. INTA pin is dedicated for interrupt. > INTB pin is used as either interrupt or clockout. The Alarm1 interrupt is > muxed into INTB by default. If the CLOCKOUT is enabled, Alarm1 irq is muxed > into INTA. We don't have further control over interrupt muxing. > - Driver checks for "#clock-cells". If it is present, it enables the clockout > so that we can get interrupt from INTA. > > The Rest: > - Has two pins: INTA/CLKIN and INTB/CLOCKOUT. Alarm1 interrupt is muxed into > INTA by default, muxed into INTB if and only if we enable CLKIN. > - Driver aborts probe with -EOPNOTSUPP when user requests interrupt, clockin > and clockout at the same time. We can't have all three with two pins. > > > Unfortunately we don't have control over the interrupt muxing other than clock > configuration. How should the driver approach this? Pinmux with two states - interrupt or clock. Best regards, Krzysztof
