From patchwork Mon Jan 28 14:23:10 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mathias Nyman X-Patchwork-Id: 2056341 Return-Path: X-Original-To: patchwork-linux-acpi@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 47686E00C6 for ; Mon, 28 Jan 2013 14:18:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756788Ab3A1OSf (ORCPT ); Mon, 28 Jan 2013 09:18:35 -0500 Received: from mga03.intel.com ([143.182.124.21]:36904 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756741Ab3A1OSe (ORCPT ); Mon, 28 Jan 2013 09:18:34 -0500 Received: from azsmga001.ch.intel.com ([10.2.17.19]) by azsmga101.ch.intel.com with ESMTP; 28 Jan 2013 06:18:34 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,551,1355126400"; d="scan'208";a="249216952" Received: from mnyman-mobl1.fi.intel.com ([10.237.72.195]) by azsmga001.ch.intel.com with ESMTP; 28 Jan 2013 06:18:31 -0800 From: Mathias Nyman To: "Rafael J. Wysocki" , Linus Cc: , , Zhang Rui , , , Mathias Nyman Subject: [RFC PATCH v2] gpiolib-acpi: Add ACPI5 event model support to gpio. Date: Mon, 28 Jan 2013 16:23:10 +0200 Message-Id: <1359382990-19353-1-git-send-email-mathias.nyman@linux.intel.com> X-Mailer: git-send-email 1.7.4.1 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org 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 Signed-off-by: Mathias Nyman --- drivers/gpio/gpiolib-acpi.c | 82 +++++++++++++++++++++++++++++++++++++++++++ include/linux/acpi_gpio.h | 4 ++ 2 files changed, 86 insertions(+), 0 deletions(-) diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index cbad6e9..54ce226 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -15,6 +15,7 @@ #include #include #include +#include static int acpi_gpiochip_find(struct gpio_chip *gc, void *data) { @@ -52,3 +53,84 @@ 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_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events + * @chip: gpio chip + * + * 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 + * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which + * gpio pins have acpi event methods and assigns interrupt handlers that calls + * the acpi event methods for those pins. + * + * Interrupts are automatically freed on driver detach + */ + +void acpi_gpiochip_request_interrupts(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_gpiochip_request_interrupts); diff --git a/include/linux/acpi_gpio.h b/include/linux/acpi_gpio.h index 91615a3..b76ebd0 100644 --- a/include/linux/acpi_gpio.h +++ b/include/linux/acpi_gpio.h @@ -2,10 +2,12 @@ #define _LINUX_ACPI_GPIO_H_ #include +#include #ifdef CONFIG_GPIO_ACPI int acpi_get_gpio(char *path, int pin); +void acpi_gpiochip_request_interrupts(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_gpiochip_request_interrupts(struct gpio_chip *chip) { } + #endif /* CONFIG_GPIO_ACPI */ #endif /* _LINUX_ACPI_GPIO_H_ */