| Message ID | 1418218575-17694-1-git-send-email-geert+renesas@glider.be |
|---|---|
| State | Under Review, archived |
| Headers | show |
On Wed, Dec 10, 2014 at 10:36 PM, Geert Uytterhoeven <geert+renesas@glider.be> wrote: > The pcf857x GPIO and interrupt controller uses dummy_irq_chip, which > does not implement irq_chip.irq_set_wake() and does not set > IRQCHIP_SKIP_SET_WAKE. > > This causes two s2ram issues if wake-up is enabled for the pcf857x GPIO > pins: > 1. During resume from s2ram, the following warning is printed: > > WARNING: CPU: 0 PID: 1046 at kernel/irq/manage.c:537 irq_set_irq_wake+0x9c/0xf8() > Unbalanced IRQ 113 wake disable > > 2. Wake-up through the pcf857x GPIO pins may fail, as the parent > interrupt controller may be suspended. > > Migrate the pcf857x GPIO and interrupt controller from dummy_irq_chip to > its own irq_chip. This irq chip implements irq_chip.irq_set_wake() to > propagate its wake-up setting to the parent interrupt controller. > > This fixes wake-up through gpio-keys on sh73a0/kzm9g, where the pcf857x > interrupt is cascaded to irq-renesas-intc-irqpin, and the latter must > not be suspended when wake-up is enabled. I am not very familiar with the IRQ subsystem, but wouldn't it be possible (and better) to try and fix/adapt dummy_irq_chip so it displays the right behavior? At least your first point looks like an issue with it. -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Alexandre, On Wed, Dec 17, 2014 at 7:01 AM, Alexandre Courbot <gnurou@gmail.com> wrote: > On Wed, Dec 10, 2014 at 10:36 PM, Geert Uytterhoeven > <geert+renesas@glider.be> wrote: >> The pcf857x GPIO and interrupt controller uses dummy_irq_chip, which >> does not implement irq_chip.irq_set_wake() and does not set >> IRQCHIP_SKIP_SET_WAKE. >> >> This causes two s2ram issues if wake-up is enabled for the pcf857x GPIO >> pins: >> 1. During resume from s2ram, the following warning is printed: >> >> WARNING: CPU: 0 PID: 1046 at kernel/irq/manage.c:537 irq_set_irq_wake+0x9c/0xf8() >> Unbalanced IRQ 113 wake disable >> >> 2. Wake-up through the pcf857x GPIO pins may fail, as the parent >> interrupt controller may be suspended. >> >> Migrate the pcf857x GPIO and interrupt controller from dummy_irq_chip to >> its own irq_chip. This irq chip implements irq_chip.irq_set_wake() to >> propagate its wake-up setting to the parent interrupt controller. >> >> This fixes wake-up through gpio-keys on sh73a0/kzm9g, where the pcf857x >> interrupt is cascaded to irq-renesas-intc-irqpin, and the latter must >> not be suspended when wake-up is enabled. > > I am not very familiar with the IRQ subsystem, but wouldn't it be > possible (and better) to try and fix/adapt dummy_irq_chip so it > displays the right behavior? At least your first point looks like an > issue with it. I fixed dummy_irq_chip in the second patch of the series ("[PATCH 2/2] [RFC] genirq: Set IRQCHIP_SKIP_SET_WAKE for no_irq_chip and dummy_irq_chip:). But please note that that would fix the warning (issue 1) only. Pcf857x still needs to propagate the wake-up setting to the parent interrupt controller to avoid the parent from being suspended if wake-up is enabled (issue 2). That cannot be done in dummy_irq_chip, as dummy_irq_chip doesn't know it is cascaded to a parent interrupt controller, nor about the interrupt number that is used for the cascade. That information is specific to the child driver. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Dec 10, 2014 at 2:36 PM, Geert Uytterhoeven <geert+renesas@glider.be> wrote: > The pcf857x GPIO and interrupt controller uses dummy_irq_chip, which > does not implement irq_chip.irq_set_wake() and does not set > IRQCHIP_SKIP_SET_WAKE. > > This causes two s2ram issues if wake-up is enabled for the pcf857x GPIO > pins: > 1. During resume from s2ram, the following warning is printed: > > WARNING: CPU: 0 PID: 1046 at kernel/irq/manage.c:537 irq_set_irq_wake+0x9c/0xf8() > Unbalanced IRQ 113 wake disable > > 2. Wake-up through the pcf857x GPIO pins may fail, as the parent > interrupt controller may be suspended. > > Migrate the pcf857x GPIO and interrupt controller from dummy_irq_chip to > its own irq_chip. This irq chip implements irq_chip.irq_set_wake() to > propagate its wake-up setting to the parent interrupt controller. > > This fixes wake-up through gpio-keys on sh73a0/kzm9g, where the pcf857x > interrupt is cascaded to irq-renesas-intc-irqpin, and the latter must > not be suspended when wake-up is enabled. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> (...) > +static struct irq_chip pcf857x_irq_chip = { > + .name = "pcf857x", > + .irq_startup = noop_ret, > + .irq_shutdown = noop, > + .irq_enable = noop, > + .irq_disable = noop, > + .irq_ack = noop, > + .irq_mask = noop, > + .irq_unmask = noop, > + .irq_set_wake = pcf857x_irq_set_wake, > +}; Argh this is so simplistic ... any GPIO irqchip worthy of it's name shoult at least call gpiochip_lock_as_irq() in .irq_request_resources() and vice versa mutatis mutandis in .irq_release_resources(). Isn't it possible to also migrate this to GPIOLIB_IRQCHIP when you're at it can also cut out a big chunk of rusty code? Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/gpio/gpio-pcf857x.c b/drivers/gpio/gpio-pcf857x.c index 236708ad0a5ba0ab..22dbecb004cf6c5b 100644 --- a/drivers/gpio/gpio-pcf857x.c +++ b/drivers/gpio/gpio-pcf857x.c @@ -218,14 +218,45 @@ static irqreturn_t pcf857x_irq(int irq, void *data) return IRQ_HANDLED; } +/* + * NOP functions + */ +static void noop(struct irq_data *data) { } + +static unsigned int noop_ret(struct irq_data *data) +{ + return 0; +} + +static int pcf857x_irq_set_wake(struct irq_data *data, unsigned int on) +{ + struct pcf857x *gpio = irq_data_get_irq_chip_data(data); + + irq_set_irq_wake(gpio->client->irq, on); + return 0; +} + +static struct irq_chip pcf857x_irq_chip = { + .name = "pcf857x", + .irq_startup = noop_ret, + .irq_shutdown = noop, + .irq_enable = noop, + .irq_disable = noop, + .irq_ack = noop, + .irq_mask = noop, + .irq_unmask = noop, + .irq_set_wake = pcf857x_irq_set_wake, +}; + static int pcf857x_irq_domain_map(struct irq_domain *domain, unsigned int irq, irq_hw_number_t hw) { struct pcf857x *gpio = domain->host_data; irq_set_chip_and_handler(irq, - &dummy_irq_chip, + &pcf857x_irq_chip, handle_level_irq); + irq_set_chip_data(irq, gpio); #ifdef CONFIG_ARM set_irq_flags(irq, IRQF_VALID); #else
The pcf857x GPIO and interrupt controller uses dummy_irq_chip, which does not implement irq_chip.irq_set_wake() and does not set IRQCHIP_SKIP_SET_WAKE. This causes two s2ram issues if wake-up is enabled for the pcf857x GPIO pins: 1. During resume from s2ram, the following warning is printed: WARNING: CPU: 0 PID: 1046 at kernel/irq/manage.c:537 irq_set_irq_wake+0x9c/0xf8() Unbalanced IRQ 113 wake disable 2. Wake-up through the pcf857x GPIO pins may fail, as the parent interrupt controller may be suspended. Migrate the pcf857x GPIO and interrupt controller from dummy_irq_chip to its own irq_chip. This irq chip implements irq_chip.irq_set_wake() to propagate its wake-up setting to the parent interrupt controller. This fixes wake-up through gpio-keys on sh73a0/kzm9g, where the pcf857x interrupt is cascaded to irq-renesas-intc-irqpin, and the latter must not be suspended when wake-up is enabled. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> --- drivers/gpio/gpio-pcf857x.c | 33 ++++++++++++++++++++++++++++++++- 1 file changed, 32 insertions(+), 1 deletion(-)