Messages in this thread | | | Date | Mon, 27 Aug 2018 10:56:44 -0600 | From | Lina Iyer <> | Subject | Re: [PATCH v2 1/5] drivers: pinctrl: qcom: add wakeup capability to GPIO |
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On Sun, Aug 26 2018 at 08:33 -0600, Linus Walleij wrote: >On Fri, Aug 17, 2018 at 6:39 PM Lina Iyer <ilina@codeaurora.org> wrote: > >> QCOM SoC's that have Power Domain Controller (PDC) chip in the always-on >> domain can wakeup the SoC, when interrupts and GPIOs are routed to the >> its interrupt controller. Only select GPIOs that are deemed wakeup >> capable are routed to specific PDC pins. During low power state, the >> pinmux interrupt controller may be non-functional but the PDC would be. >> The PDC can detect the wakeup GPIO is triggered and bring the TLMM to an >> operational state. >> >> Interrupts that are level triggered will be detected at the TLMM when >> the controller becomes operational. Edge interrupts however need to be >> replayed again. >> >> Request the corresponding PDC IRQ, when the GPIO is requested as an IRQ, >> but keep it disabled. During suspend, we can enable the PDC IRQ instead >> of the GPIO IRQ, which may or not be detected. >> >> Signed-off-by: Lina Iyer <ilina@codeaurora.org> >> --- >> Changes in v1: >> - Trigger GPIO in h/w from PDC IRQ handler >> - Avoid big tables for GPIO-PDC map, pick from DT instead >> - Use handler_data > >Just for the record this is an impressive and much needed patch >set, no other SoC developer has yet taken on the task of making this >work so I very much appreciate that Qualcomm show the way. > >> +static int msm_gpio_pdc_pin_request(struct irq_data *d) >> +static int msm_gpio_pdc_pin_release(struct irq_data *d) >> +static int msm_gpio_irq_reqres(struct irq_data *d) >> +{ >(...) >> + if (gpiochip_lock_as_irq(gc, irqd_to_hwirq(d))) { >(...) >> +static void msm_gpio_irq_relres(struct irq_data *d) >> +{ >> + gpiochip_unlock_as_irq(gc, irqd_to_hwirq(d)); >> +} > >FYI Hans Verkuil is working on a patch set that moves the >lock/unlock as IRQ call to the irqchip request() and release() >functions so we can switch a GPIO irqchip line from IRQ >mode to say output at runtime without too much trouble. >(CEC needs this.) > Thanks, I will look into Hans's RFCv2. But what would help me would be to avoid creating the IRQ for the GPIO itself (I have the latent IRQ), if I could just return that instead in gpio_to_irq(), it might be easier. I understand ->to_irq() is supposed to be a translate function only, I can avoid the dance of enabling and diabling the PDC IRQ on suspend and resume.
-- Lina
>I suspect that will make your work easier? > >Hans can you include Lina in the loop for your patches >so she can take that into accoun because I think we might >need that as a base for this. > >Yours, >Linus Walleij
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