On Friday, January 25, 2013 01:48:25 PM Mathias Nyman wrote: > Add ability to handle ACPI events signalled by GPIO interrupts. > > ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are > handled by ACPI event methods which need to be called from the GPIO > controller's interrupt handler. acpi_gpio_request_interrupt() finds out which > gpio pins have acpi event methods and assigns interrupt handlers that calls > the acpi event methods for those pins. > > Partially based on work by Rui Zhang <[email protected]> > > Signed-off-by: Mathias Nyman <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]> > --- > drivers/gpio/gpiolib-acpi.c | 80 > +++++++++++++++++++++++++++++++++++++++++++ > include/linux/acpi_gpio.h | 4 ++ > 2 files changed, 84 insertions(+), 0 deletions(-) > > diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c > index cbad6e9..b6ab041 100644 > --- a/drivers/gpio/gpiolib-acpi.c > +++ b/drivers/gpio/gpiolib-acpi.c > @@ -15,6 +15,7 @@ > #include <linux/export.h> > #include <linux/acpi_gpio.h> > #include <linux/acpi.h> > +#include <linux/interrupt.h> > > static int acpi_gpiochip_find(struct gpio_chip *gc, void *data) > { > @@ -52,3 +53,82 @@ int acpi_get_gpio(char *path, int pin) > return chip->base + pin; > } > EXPORT_SYMBOL_GPL(acpi_get_gpio); > + > + > +static irqreturn_t acpi_gpio_irq_handler(int irq, void *data) > +{ > + acpi_handle handle = data; > + > + acpi_evaluate_object(handle, NULL, NULL, NULL); > + > + return IRQ_HANDLED; > +} > + > +/** > + * acpi_gpio_request_interrupt() - Register isr for gpio controller ACPI > events > + * @chip: gpio chip representation of the gpio controller > + * > + * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts > are > + * handled by ACPI event methods which need to be called from the GPIO > + * controller's interrupt handler. acpi_gpio_request_interrupt finds out > which > + * gpio pins have acpi event methods and assigns interrupt handlers that > calls > + * the acpi event methods for those pins. > + */ > + > +void acpi_gpio_request_interrupt(struct gpio_chip *chip) > +{ > + struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL}; > + struct acpi_resource *res; > + acpi_handle handle, ev_handle; > + acpi_status status; > + unsigned int pin, irq; > + char ev_name[5]; > + > + if (!chip->dev || !chip->to_irq) > + return; > + > + handle = ACPI_HANDLE(chip->dev); > + if (!handle) > + return; > + > + status = acpi_get_event_resources(handle, &buf); > + if (ACPI_FAILURE(status)) > + return; > + > + /* If a gpio interrupt has an acpi event handler method, then > + * set up an interrupt handler that calls the acpi event handler > + */ > + > + for (res = buf.pointer; > + res && (res->type != ACPI_RESOURCE_TYPE_END_TAG); > + res = ACPI_NEXT_RESOURCE(res)) { > + > + if (res->type != ACPI_RESOURCE_TYPE_GPIO || > + res->data.gpio.connection_type != > + ACPI_RESOURCE_GPIO_TYPE_INT) > + continue; > + > + pin = res->data.gpio.pin_table[0]; > + if (pin > chip->ngpio) > + continue; > + > + sprintf(ev_name, "_%c%02X", > + res->data.gpio.triggering ? 'E' : 'L', pin); > + > + status = acpi_get_handle(handle, ev_name, &ev_handle); > + if (ACPI_FAILURE(status)) > + continue; > + > + irq = chip->to_irq(chip, pin); > + if (irq < 0) > + continue; > + > + /* Assume BIOS sets the triggering, so no flags */ > + devm_request_threaded_irq(chip->dev, irq, NULL, > + acpi_gpio_irq_handler, > + 0, > + "GPIO-signaled-ACPI-event", > + ev_handle); > + } > +} > +EXPORT_SYMBOL(acpi_gpio_request_interrupt); > diff --git a/include/linux/acpi_gpio.h b/include/linux/acpi_gpio.h > index 91615a3..43c541d 100644 > --- a/include/linux/acpi_gpio.h > +++ b/include/linux/acpi_gpio.h > @@ -2,10 +2,12 @@ > #define _LINUX_ACPI_GPIO_H_ > > #include <linux/errno.h> > +#include <linux/gpio.h> > > #ifdef CONFIG_GPIO_ACPI > > int acpi_get_gpio(char *path, int pin); > +void acpi_gpio_request_interrupt(struct gpio_chip *chip); > > #else /* CONFIG_GPIO_ACPI */ > > @@ -14,6 +16,8 @@ static inline int acpi_get_gpio(char *path, int pin) > return -ENODEV; > } > > +static inline void acpi_gpio_request_interrupt(struct gpio_chip *chip) { } > + > #endif /* CONFIG_GPIO_ACPI */ > > #endif /* _LINUX_ACPI_GPIO_H_ */ > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
