From patchwork Wed Mar 20 10:39:27 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 1059047 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-gpio-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=glider.be Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44PRHr4WHHz9sDn for ; Wed, 20 Mar 2019 21:39:36 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727882AbfCTKje (ORCPT ); Wed, 20 Mar 2019 06:39:34 -0400 Received: from michel.telenet-ops.be ([195.130.137.88]:39328 "EHLO michel.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727647AbfCTKjd (ORCPT ); Wed, 20 Mar 2019 06:39:33 -0400 Received: from ramsan ([84.194.111.163]) by michel.telenet-ops.be with bizsmtp id qAfV1z00B3XaVaC06AfVU0; Wed, 20 Mar 2019 11:39:30 +0100 Received: from rox.of.borg ([192.168.97.57]) by ramsan with esmtp (Exim 4.90_1) (envelope-from ) id 1h6Yd7-0005La-9L; Wed, 20 Mar 2019 11:39:29 +0100 Received: from geert by rox.of.borg with local (Exim 4.90_1) (envelope-from ) id 1h6Yd7-0005X6-7t; Wed, 20 Mar 2019 11:39:29 +0100 From: Geert Uytterhoeven To: Linus Walleij , Bartosz Golaszewski , "Rafael J . Wysocki" , Ulf Hansson , Kevin Hilman Cc: Laurent Pinchart , linux-gpio@vger.kernel.org, linux-pm@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH RFC] gpio: pca953x: Configure wake-up path when wake-up is enabled Date: Wed, 20 Mar 2019 11:39:27 +0100 Message-Id: <20190320103927.21227-1-geert+renesas@glider.be> X-Mailer: git-send-email 2.17.1 Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org If a device is part of the wake-up path, it should indicate this by setting its power.wakeup_path field. This allows the genpd core code to keep the device enabled during system suspend when needed. As regulators powering devices are not handled by genpd, the driver handles these itself, and thus must skip regulator control when the device is part of the wake-up path. Signed-off-by: Geert Uytterhoeven Reviewed-by: Ulf Hansson --- Note that I don't really need this on the Renesas Ebisu-4D board, as there is no regulator or PM Domain controlling power to the GPIO expander on that board. I did want to have all wake-up path processing implemented in the driver for completeness, and did test its behavior with gpio-keys configured as a wake-up source. However, while this approach is known to work fine on other boards, with other GPIO and interrupt controllers (gpio-rcar, irq-renesas-irqc, irq-renesas-intc-irqpin), it wouldn't work on Ebisu-4D, due to different device suspend ordering. The proper ordering is: 1. When gpio-keys is suspended, its suspend handler calls enable_irq_wake(), invoking pca953x_irq_set_wake(), and causing pca953x_chip.wakeup_path to be incremented, 2. When gpio-pca953x is suspended, it checks pca953x_chip.wakeup_path, and marks the device to be part of the wake-up path. However, gpio-keys is suspended _after_ gpio-pca953x, breaking the scheme :-( So depending on topology, this may work, or not... --- drivers/gpio/gpio-pca953x.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index 88c94d155e218535..349d0ccb5285a6c4 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -153,6 +153,7 @@ struct pca953x_chip { u8 irq_trig_fall[MAX_BANK]; struct irq_chip irq_chip; #endif + atomic_t wakeup_path; struct i2c_client *client; struct gpio_chip gpio_chip; @@ -581,6 +582,11 @@ static int pca953x_irq_set_wake(struct irq_data *d, unsigned int on) struct gpio_chip *gc = irq_data_get_irq_chip_data(d); struct pca953x_chip *chip = gpiochip_get_data(gc); + if (on) + atomic_inc(&chip->wakeup_path); + else + atomic_dec(&chip->wakeup_path); + return irq_set_irq_wake(chip->client->irq, on); } @@ -1100,7 +1106,10 @@ static int pca953x_suspend(struct device *dev) regcache_cache_only(chip->regmap, true); - regulator_disable(chip->regulator); + if (atomic_read(&chip->wakeup_path)) + device_set_wakeup_path(dev); + else + regulator_disable(chip->regulator); return 0; } @@ -1110,10 +1119,12 @@ static int pca953x_resume(struct device *dev) struct pca953x_chip *chip = dev_get_drvdata(dev); int ret; - ret = regulator_enable(chip->regulator); - if (ret != 0) { - dev_err(dev, "Failed to enable regulator: %d\n", ret); - return 0; + if (!atomic_read(&chip->wakeup_path)) { + ret = regulator_enable(chip->regulator); + if (ret != 0) { + dev_err(dev, "Failed to enable regulator: %d\n", ret); + return 0; + } } regcache_cache_only(chip->regmap, false);