On 29/01/2025 09:46, Abel Vesa wrote: >> >>> 1. Maybe the driver just lacks proper suspend/resume handling? >>> I assume all this happens during system suspend, so what certainty you >>> have that your second work - pmic_glink_altmode_pdr_notify() - is not >>> executed as well? >>> >>> 2. Follow up: all other drivers and all other future use cases will be >>> affected as well. Basically what this patch is admitting is that driver >>> can be executed anytime, even during suspend, so each call of >>> pmic_glink_send() has to be audited. Now and in the future, because what >>> stops some developer of adding one more path calling pmic_glink_send(), >>> which also turns out to be executed during suspend? >>> >>> 3. So qcom_battmgr.c is buggy as well? >>> >>> 4. ucsi_glink.c? I don't see handling suspend, either... >>> >>> Maybe the entire problem is how pmic glink was designed: not as proper >>> bus driver which handles both child-parent relationship and system suspend. >> >> The underlying problem is that GLINK register its interrupt as >> IRQF_NO_SUSPEND (for historical reasons) and as such incoming messages >> will be delivered in late suspend and early resume. In this specific >> case, a specific message is handled by pmic_glink_altmode_callback(), by >> invoking schedule_work() which in this case happens to schedule >> pmic_glink_altmode_worker before we've resumed the I2C controller. >> >> I presume with your suggestion about a pmic_glink bus driver we'd come >> up with some mechanism for pmic_glink to defer these messages until >> resume has happened? > > So is the suggestion here to rework the entire pmic_glink into a bus > driver? (I like the sound of that) > > I'd assume the new bus driver will have to queue the messages until it > has resumed, which is fine. Queue or just disable interrupts/notifications to clients. > > But still doesn't solve the fact that we can't filter out when to > wake-up or not. What am I missing here? I think this was not the concern in my email. I was only wondering about the design flaw that we allow pmic glink to send notifications to children anytime. And that's not how the bus-like driver should be written. Best regards, Krzysztof
