From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1D78E27CB02; Wed, 25 Feb 2026 01:45:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771983930; cv=none; b=LCUMzBD8zkzg4cqb/SZckFYtowTsuh8zZ44wVD71mzbVgtYrFVt0en7W2BKffEL+blAxssSGuOQrODiGlDccLFNncZTtqnSgu09xnUeoEVHON08OtNysAGhpoG6p1E/6c46ROOsEsRU8R1hw/30hD+pFblMw/4KWh25hqMtq/Pg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771983930; c=relaxed/simple; bh=Wm4uMaBKYzooYVFHrPuR5n3TL6MSrD2p+j/yu9u/5dY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=sKEs3jhbXEfal/UTr8pca5Ew2W/z4/OUzzDGoo704NYQtzyz2VfXySjInO20CgMY/3JLBQoO9zgPKBzOt1NDMxLV06jibOezXkN/uWy0WqzeGH6r6WeKZOGLgKUwsHCW7pNKqIgBv8fixR42tAZPZ3rGZsaVSBqJfJonVHjH578= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=OsB9plGO; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="OsB9plGO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9B27C116D0; Wed, 25 Feb 2026 01:45:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1771983930; bh=Wm4uMaBKYzooYVFHrPuR5n3TL6MSrD2p+j/yu9u/5dY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OsB9plGO9YHfoJqPJ6GpsPsk2YWlp19sazUIq9k4zu0FnSwGNK4knYWm946nsCb4l v4Pp+TQ7qKOBz4yGkjTmwsfKBUz3+qI4HBzeO1yPIB/qfvWWHy7a6GRnUtaW/rWBza Zy+I0FlpHjaB4QkvK+DaLpJ3+e5LbkiuhTXq3bh4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Andr=C3=A9=20Draszik?= , Mark Brown , Sasha Levin Subject: [PATCH 6.18 196/641] regulator: core: move supply check earlier in set_machine_constraints() Date: Tue, 24 Feb 2026 17:18:42 -0800 Message-ID: <20260225012353.736989407@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260225012348.915798704@linuxfoundation.org> References: <20260225012348.915798704@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: André Draszik [ Upstream commit 86a8eeb0e913f4b6a55dabba5122098d4e805e55 ] Since commit 98e48cd9283d ("regulator: core: resolve supply for boot-on/always-on regulators"), set_machine_constraints() can return -EPROBE_DEFER very late, after it has done a lot of work and configuration of the regulator. This means that configuration will happen multiple times for no benefit in that case. Furthermore, this can lead to timing-dependent voltage glitches as mentioned e.g. in commit 8a866d527ac0 ("regulator: core: Resolve supply name earlier to prevent double-init"). We can know that it's going to fail very early, in particular before going through the complete regulator configuration by moving some code around a little. Do so to avoid re-configuring the regulator multiple times, also avoiding the voltage glitches if we can. Fixes: 98e48cd9283d ("regulator: core: resolve supply for boot-on/always-on regulators") Signed-off-by: André Draszik Link: https://patch.msgid.link/20260109-regulators-defer-v2-3-1a25dc968e60@linaro.org Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/regulator/core.c | 55 ++++++++++++++++++++++------------------ 1 file changed, 30 insertions(+), 25 deletions(-) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index b38b087eccfd7..17c60d9547dc5 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1431,6 +1431,33 @@ static int set_machine_constraints(struct regulator_dev *rdev) int ret = 0; const struct regulator_ops *ops = rdev->desc->ops; + /* + * If there is no mechanism for controlling the regulator then + * flag it as always_on so we don't end up duplicating checks + * for this so much. Note that we could control the state of + * a supply to control the output on a regulator that has no + * direct control. + */ + if (!rdev->ena_pin && !ops->enable) { + if (rdev->supply_name && !rdev->supply) + return -EPROBE_DEFER; + + if (rdev->supply) + rdev->constraints->always_on = + rdev->supply->rdev->constraints->always_on; + else + rdev->constraints->always_on = true; + } + + /* + * If we want to enable this regulator, make sure that we know the + * supplying regulator. + */ + if (rdev->constraints->always_on || rdev->constraints->boot_on) { + if (rdev->supply_name && !rdev->supply) + return -EPROBE_DEFER; + } + ret = machine_constraints_voltage(rdev, rdev->constraints); if (ret != 0) return ret; @@ -1596,37 +1623,15 @@ static int set_machine_constraints(struct regulator_dev *rdev) } } - /* - * If there is no mechanism for controlling the regulator then - * flag it as always_on so we don't end up duplicating checks - * for this so much. Note that we could control the state of - * a supply to control the output on a regulator that has no - * direct control. - */ - if (!rdev->ena_pin && !ops->enable) { - if (rdev->supply_name && !rdev->supply) - return -EPROBE_DEFER; - - if (rdev->supply) - rdev->constraints->always_on = - rdev->supply->rdev->constraints->always_on; - else - rdev->constraints->always_on = true; - } - /* If the constraints say the regulator should be on at this point * and we have control then make sure it is enabled. */ if (rdev->constraints->always_on || rdev->constraints->boot_on) { bool supply_enabled = false; - /* If we want to enable this regulator, make sure that we know - * the supplying regulator. - */ - if (rdev->supply_name && !rdev->supply) - return -EPROBE_DEFER; - - /* If supplying regulator has already been enabled, + /* We have ensured a potential supply has been resolved above. + * + * If supplying regulator has already been enabled, * it's not intended to have use_count increment * when rdev is only boot-on. */ -- 2.51.0