From patchwork Fri Aug 11 11:04:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Lindgren X-Patchwork-Id: 13350666 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F09C4C0015E for ; Fri, 11 Aug 2023 11:04:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234502AbjHKLEo (ORCPT ); Fri, 11 Aug 2023 07:04:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41494 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234530AbjHKLEn (ORCPT ); Fri, 11 Aug 2023 07:04:43 -0400 Received: from muru.com (muru.com [72.249.23.125]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id BA2F1FD; Fri, 11 Aug 2023 04:04:42 -0700 (PDT) Received: from hillo.muru.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTP id CAAA0820B; Fri, 11 Aug 2023 11:04:40 +0000 (UTC) From: Tony Lindgren To: Dmitry Torokhov Cc: Rob Herring , Krzysztof Kozlowski , Conor Dooley , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Dhruva Gole Subject: [PATCH 2/2] Input: gpio-keys - Add system suspend support for dedicated wakeirqs Date: Fri, 11 Aug 2023 14:04:32 +0300 Message-ID: <20230811110432.3968-2-tony@atomide.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230811110432.3968-1-tony@atomide.com> References: <20230811110432.3968-1-tony@atomide.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org Some SoCs have a separate dedicated wake-up interrupt controller that can be used to wake up the system from deeper idle states. We already support configuring a separate interrupt for a gpio-keys button to be used with a gpio line. However, we are lacking support system suspend for cases where a separate interrupt needs to be used in deeper sleep modes. Because of it's nature, gpio-keys does not know about the runtime PM state of the button gpios, and may have several gpio buttons configured for each gpio-keys device instance. Implementing runtime PM support for gpio-keys does not help, and we cannot use drivers/base/power/wakeirq.c support. We need to implement custom wakeirq support for gpio-keys. For handling a dedicated wakeirq for system suspend, we enable and disable it with gpio_keys_enable_wakeup() and gpio_keys_disable_wakeup() that we already use based on device_may_wakeup(). Some systems may have a dedicated wakeirq that can also be used as the main interrupt, this is already working for gpio-keys. Let's add some wakeirq related comments while at it as the usage with a gpio line and separate interrupt line may not be obvious. Tested-by: Dhruva Gole Signed-off-by: Tony Lindgren --- drivers/input/keyboard/gpio_keys.c | 69 ++++++++++++++++++++++++++++-- include/linux/gpio_keys.h | 2 + 2 files changed, 67 insertions(+), 4 deletions(-) diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c --- a/drivers/input/keyboard/gpio_keys.c +++ b/drivers/input/keyboard/gpio_keys.c @@ -45,7 +45,9 @@ struct gpio_button_data { unsigned int software_debounce; /* in msecs, for GPIO-driven buttons */ unsigned int irq; + unsigned int wakeirq; unsigned int wakeup_trigger_type; + spinlock_t lock; bool disabled; bool key_pressed; @@ -511,6 +513,7 @@ static int gpio_keys_setup_key(struct platform_device *pdev, struct gpio_button_data *bdata = &ddata->data[idx]; irq_handler_t isr; unsigned long irqflags; + const char *wakedesc; int irq; int error; @@ -575,6 +578,14 @@ static int gpio_keys_setup_key(struct platform_device *pdev, !gpiod_cansleep(bdata->gpiod); } + /* + * If an interrupt was specified, use it instead of the gpio + * interrupt and use the gpio for reading the state. A separate + * interrupt may be used as the main button interrupt for + * runtime PM to detect events also in deeper idle states. If a + * dedicated wakeirq is used for system suspend only, see below + * for bdata->wakeirq setup. + */ if (button->irq) { bdata->irq = button->irq; } else { @@ -672,6 +683,36 @@ static int gpio_keys_setup_key(struct platform_device *pdev, return error; } + if (!button->wakeirq) + return 0; + + /* Use :wakeup suffix like drivers/base/power/wakeirq.c does */ + wakedesc = devm_kasprintf(dev, GFP_KERNEL, "%s:wakeup", desc); + if (!wakedesc) + return -ENOMEM; + + bdata->wakeirq = button->wakeirq; + irqflags |= IRQF_NO_SUSPEND; + + /* + * Wakeirq shares the handler with the main interrupt, it's only + * active during system suspend. See gpio_keys_button_enable_wakeup() + * and gpio_keys_button_disable_wakeup(). + */ + error = devm_request_any_context_irq(dev, bdata->wakeirq, isr, + irqflags, wakedesc, bdata); + if (error < 0) { + dev_err(dev, "Unable to claim wakeirq %d; error %d\n", + bdata->irq, error); + return error; + } + + /* + * Disable wakeirq until suspend. IRQF_NO_AUTOEN won't work if + * IRQF_SHARED was set based on !button->can_disable. + */ + disable_irq_nosync(bdata->wakeirq); + return 0; } @@ -728,7 +769,7 @@ gpio_keys_get_devtree_pdata(struct device *dev) struct gpio_keys_platform_data *pdata; struct gpio_keys_button *button; struct fwnode_handle *child; - int nbuttons; + int nbuttons, irq; nbuttons = device_get_child_node_count(dev); if (nbuttons == 0) @@ -750,9 +791,19 @@ gpio_keys_get_devtree_pdata(struct device *dev) device_property_read_string(dev, "label", &pdata->name); device_for_each_child_node(dev, child) { - if (is_of_node(child)) - button->irq = - irq_of_parse_and_map(to_of_node(child), 0); + if (is_of_node(child)) { + irq = of_irq_get_byname(to_of_node(child), "irq"); + if (irq > 0) + button->irq = irq; + + irq = of_irq_get_byname(to_of_node(child), "wakeup"); + if (irq > 0) + button->wakeirq = irq; + + if (!button->irq && !button->wakeirq) + button->irq = + irq_of_parse_and_map(to_of_node(child), 0); + } if (fwnode_property_read_u32(child, "linux,code", &button->code)) { @@ -921,6 +972,11 @@ gpio_keys_button_enable_wakeup(struct gpio_button_data *bdata) } } + if (bdata->wakeirq) { + enable_irq(bdata->wakeirq); + disable_irq_nosync(bdata->irq); + } + return 0; } @@ -929,6 +985,11 @@ gpio_keys_button_disable_wakeup(struct gpio_button_data *bdata) { int error; + if (bdata->wakeirq) { + enable_irq(bdata->irq); + disable_irq_nosync(bdata->wakeirq); + } + /* * The trigger type is always both edges for gpio-based keys and we do * not support changing wakeup trigger for interrupt-based keys. diff --git a/include/linux/gpio_keys.h b/include/linux/gpio_keys.h --- a/include/linux/gpio_keys.h +++ b/include/linux/gpio_keys.h @@ -21,6 +21,7 @@ struct device; * disable button via sysfs * @value: axis value for %EV_ABS * @irq: Irq number in case of interrupt keys + * @wakeirq: Optional dedicated wake-up interrupt */ struct gpio_keys_button { unsigned int code; @@ -34,6 +35,7 @@ struct gpio_keys_button { bool can_disable; int value; unsigned int irq; + unsigned int wakeirq; }; /**