From patchwork Thu May 30 10:16:06 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yoshihiro Shimoda X-Patchwork-Id: 1107685 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-pwm-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=renesas.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45F3Wh3RRHz9s9N for ; Thu, 30 May 2019 20:21:04 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727976AbfE3KVD (ORCPT ); Thu, 30 May 2019 06:21:03 -0400 Received: from relmlor1.renesas.com ([210.160.252.171]:16431 "EHLO relmlie5.idc.renesas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727889AbfE3KVC (ORCPT ); Thu, 30 May 2019 06:21:02 -0400 X-IronPort-AV: E=Sophos;i="5.60,530,1549897200"; d="scan'208";a="17378683" Received: from unknown (HELO relmlir6.idc.renesas.com) ([10.200.68.152]) by relmlie5.idc.renesas.com with ESMTP; 30 May 2019 19:20:59 +0900 Received: from localhost.localdomain (unknown [10.166.17.210]) by relmlir6.idc.renesas.com (Postfix) with ESMTP id 9C4E74235972; Thu, 30 May 2019 19:20:59 +0900 (JST) From: Yoshihiro Shimoda To: thierry.reding@gmail.com Cc: linux-pwm@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Yoshihiro Shimoda Subject: [PATCH v2 3/4] pwm: sysfs: Add suspend/resume support Date: Thu, 30 May 2019 19:16:06 +0900 Message-Id: <1559211367-25106-4-git-send-email-yoshihiro.shimoda.uh@renesas.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1559211367-25106-1-git-send-email-yoshihiro.shimoda.uh@renesas.com> References: <1559211367-25106-1-git-send-email-yoshihiro.shimoda.uh@renesas.com> Sender: linux-pwm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org According to the Documentation/pwm.txt, all PWM consumers should have power management. Since this sysfs interface is one of consumers so that this patch adds suspend/resume support. Signed-off-by: Yoshihiro Shimoda Reviewed-by: Geert Uytterhoeven --- drivers/pwm/sysfs.c | 100 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 100 insertions(+) diff --git a/drivers/pwm/sysfs.c b/drivers/pwm/sysfs.c index 7eb4a13..2cbfb20 100644 --- a/drivers/pwm/sysfs.c +++ b/drivers/pwm/sysfs.c @@ -18,6 +18,7 @@ struct pwm_export { struct device child; struct pwm_device *pwm; struct mutex lock; + struct pwm_state suspend; }; static struct pwm_export *child_to_pwm_export(struct device *child) @@ -372,10 +373,109 @@ static struct attribute *pwm_chip_attrs[] = { }; ATTRIBUTE_GROUPS(pwm_chip); +static struct pwm_export *pwm_class_get_state(struct device *parent, + struct pwm_device *pwm, + struct pwm_state *state) +{ + struct device *child; + struct pwm_export *export; + + if (!test_bit(PWMF_EXPORTED, &pwm->flags)) + return NULL; + + child = device_find_child(parent, pwm, pwm_unexport_match); + if (!child) + return NULL; + + export = child_to_pwm_export(child); + put_device(child); /* for device_find_child() */ + + mutex_lock(&export->lock); + pwm_get_state(pwm, state); + + return export; +} + +static int pwm_class_apply_state(struct pwm_export *export, + struct pwm_device *pwm, + struct pwm_state *state) +{ + int ret = pwm_apply_state(pwm, state); + + mutex_unlock(&export->lock); + + return ret; +} + +static int pwm_class_resume_npwm(struct device *parent, unsigned int npwm) +{ + struct pwm_chip *chip = dev_get_drvdata(parent); + unsigned int i; + int ret = 0; + + for (i = 0; i < npwm; i++) { + struct pwm_device *pwm = &chip->pwms[i]; + struct pwm_state state; + struct pwm_export *export; + + export = pwm_class_get_state(parent, pwm, &state); + if (!export) + continue; + + state.enabled = export->suspend.enabled; + ret = pwm_class_apply_state(export, pwm, &state); + if (ret < 0) + break; + } + + return ret; +} + +static int pwm_class_resume(struct device *parent) +{ + struct pwm_chip *chip = dev_get_drvdata(parent); + + return pwm_class_resume_npwm(parent, chip->npwm); +} + +static int pwm_class_suspend(struct device *parent) +{ + struct pwm_chip *chip = dev_get_drvdata(parent); + unsigned int i; + int ret = 0; + + for (i = 0; i < chip->npwm; i++) { + struct pwm_device *pwm = &chip->pwms[i]; + struct pwm_state state; + struct pwm_export *export; + + export = pwm_class_get_state(parent, pwm, &state); + if (!export) + continue; + + export->suspend = state; + state.enabled = false; + ret = pwm_class_apply_state(export, pwm, &state); + if (ret < 0) { + /* + * roll back the PWM devices that were disabled by + * this suspend function. + */ + pwm_class_resume_npwm(parent, i); + break; + } + } + + return ret; +} + +static SIMPLE_DEV_PM_OPS(pwm_class_pm_ops, pwm_class_suspend, pwm_class_resume); + static struct class pwm_class = { .name = "pwm", .owner = THIS_MODULE, .dev_groups = pwm_chip_groups, + .pm = &pwm_class_pm_ops, }; static int pwmchip_sysfs_match(struct device *parent, const void *data)