Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755723AbbDUPdA (ORCPT ); Tue, 21 Apr 2015 11:33:00 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:57147 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755670AbbDUPcy (ORCPT ); Tue, 21 Apr 2015 11:32:54 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Javier Martinez Canillas , Mark Brown , Luis Henriques Subject: [PATCH 3.16.y-ckt 021/144] regulator: Only enable disabled regulators on resume Date: Tue, 21 Apr 2015 16:30:06 +0100 Message-Id: <1429630329-21748-22-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1429630329-21748-1-git-send-email-luis.henriques@canonical.com> References: <1429630329-21748-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2039 Lines: 53 3.16.7-ckt10 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Javier Martinez Canillas commit 0548bf4f5ad6fc3bd93c4940fa48078b34609682 upstream. The _regulator_do_enable() call ought to be a no-op when called on an already-enabled regulator. However, as an optimization _regulator_enable() doesn't call _regulator_do_enable() on an already enabled regulator. That means we never test the case of calling _regulator_do_enable() during normal usage and there may be hidden bugs or warnings. We have seen warnings issued by the tps65090 driver and bugs when using the GPIO enable pin. Let's match the same optimization that _regulator_enable() in regulator_suspend_finish(). That may speed up suspend/resume and also avoids exposing hidden bugs. [Use much clearer commit message from Doug Anderson] Signed-off-by: Javier Martinez Canillas Signed-off-by: Mark Brown Signed-off-by: Luis Henriques --- drivers/regulator/core.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index b4686ea6d66b..0d3723797fbd 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -3657,9 +3657,11 @@ int regulator_suspend_finish(void) list_for_each_entry(rdev, ®ulator_list, list) { mutex_lock(&rdev->mutex); if (rdev->use_count > 0 || rdev->constraints->always_on) { - error = _regulator_do_enable(rdev); - if (error) - ret = error; + if (!_regulator_is_enabled(rdev)) { + error = _regulator_do_enable(rdev); + if (error) + ret = error; + } } else { if (!have_full_constraints()) goto unlock; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/