From patchwork Tue Mar 5 19:57:59 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Krzysztof Kozlowski X-Patchwork-Id: 1051982 X-Patchwork-Delegate: promsoft@gmail.com 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=lists.denx.de (client-ip=81.169.180.215; helo=lists.denx.de; envelope-from=u-boot-bounces@lists.denx.de; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="aduk/WtZ"; dkim-atps=neutral Received: from lists.denx.de (dione.denx.de [81.169.180.215]) by ozlabs.org (Postfix) with ESMTP id 44DST91ZVxz9s3q for ; Wed, 6 Mar 2019 07:01:33 +1100 (AEDT) Received: by lists.denx.de (Postfix, from userid 105) id C32A4C21E2C; Tue, 5 Mar 2019 20:00:02 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lists.denx.de X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=T_DKIM_INVALID autolearn=unavailable autolearn_force=no version=3.4.0 Received: from lists.denx.de (localhost [IPv6:::1]) by lists.denx.de (Postfix) with ESMTP id 249C5C21E07; Tue, 5 Mar 2019 19:59:34 +0000 (UTC) Received: by lists.denx.de (Postfix, from userid 105) id 94EBAC21DAF; Tue, 5 Mar 2019 19:58:48 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by lists.denx.de (Postfix) with ESMTPS id CC2DBC21D9A for ; Tue, 5 Mar 2019 19:58:43 +0000 (UTC) Received: from localhost.localdomain (unknown [194.230.155.153]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1230A20842; Tue, 5 Mar 2019 19:58:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1551815922; bh=yPkiH97quK8rj/gA73HxSwNhE6YOJ7bI0MXMPZKVYNo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aduk/WtZDj/N+Gl0S9xXmMcwXc+6lh22jB+wzrU+FRmGozdtfcQ8DnaNFayWFL139 kEWy09bm7YsB7sYwbXypd/xPZB8wzN85fODiJJvpZAM5H+0JLRWEnv1auaVDbrQGGh 0TmOmrd18U9gTk6IWUPNEvcMKoPcCksyme7GdGBc= From: Krzysztof Kozlowski To: Albert Aribaud , Jaehoon Chung , Lukasz Majewski , Krzysztof Kozlowski , Simon Glass , Minkyu Kang , Marek Szyprowski , u-boot@lists.denx.de Date: Tue, 5 Mar 2019 20:57:59 +0100 Message-Id: <20190305195802.14397-7-krzk@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190305195802.14397-1-krzk@kernel.org> References: <20190305195802.14397-1-krzk@kernel.org> Subject: [U-Boot] [PATCH v4 6/9] regulator: Add support for ramp delay X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.18 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" Changing voltage and enabling regulator might require delays so the regulator stabilizes at expected level. Add support for "regulator-ramp-delay" binding which can introduce required time to both enabling the regulator and to changing the voltage. Signed-off-by: Krzysztof Kozlowski Tested-by: Anand Moon --- .../regulator/regulator.txt | 2 + drivers/power/regulator/regulator-uclass.c | 47 ++++++++++++++++++- include/power/regulator.h | 2 + 3 files changed, 49 insertions(+), 2 deletions(-) diff --git a/doc/device-tree-bindings/regulator/regulator.txt b/doc/device-tree-bindings/regulator/regulator.txt index 65b69c427899..4ba642b7c77f 100644 --- a/doc/device-tree-bindings/regulator/regulator.txt +++ b/doc/device-tree-bindings/regulator/regulator.txt @@ -35,6 +35,7 @@ Optional properties: - regulator-max-microamp: a maximum allowed Current value - regulator-always-on: regulator should never be disabled - regulator-boot-on: enabled by bootloader/firmware +- regulator-ramp-delay: ramp delay for regulator (in uV/us) Note The "regulator-name" constraint is used for setting the device's uclass @@ -60,4 +61,5 @@ ldo0 { regulator-max-microamp = <100000>; regulator-always-on; regulator-boot-on; + regulator-ramp-delay = <12000>; }; diff --git a/drivers/power/regulator/regulator-uclass.c b/drivers/power/regulator/regulator-uclass.c index 6f355b969a6d..9118b8eb39e3 100644 --- a/drivers/power/regulator/regulator-uclass.c +++ b/drivers/power/regulator/regulator-uclass.c @@ -35,10 +35,22 @@ int regulator_get_value(struct udevice *dev) return ops->get_value(dev); } +static void regulator_set_value_ramp_delay(struct udevice *dev, int old_uV, + int new_uV, unsigned int ramp_delay) +{ + int delay = DIV_ROUND_UP(abs(new_uV - old_uV), ramp_delay); + + debug("regulator %s: delay %u us (%d uV -> %d uV)\n", dev->name, delay, + old_uV, new_uV); + + udelay(delay); +} + int regulator_set_value(struct udevice *dev, int uV) { const struct dm_regulator_ops *ops = dev_get_driver_ops(dev); struct dm_regulator_uclass_platdata *uc_pdata; + int ret, old_uV = uV, is_enabled = 0; uc_pdata = dev_get_uclass_platdata(dev); if (uc_pdata->min_uV != -ENODATA && uV < uc_pdata->min_uV) @@ -49,7 +61,20 @@ int regulator_set_value(struct udevice *dev, int uV) if (!ops || !ops->set_value) return -ENOSYS; - return ops->set_value(dev, uV); + if (uc_pdata->ramp_delay) { + is_enabled = regulator_get_enable(dev); + old_uV = regulator_get_value(dev); + } + + ret = ops->set_value(dev, uV); + + if (!ret) { + if (uc_pdata->ramp_delay && old_uV > 0 && is_enabled) + regulator_set_value_ramp_delay(dev, old_uV, uV, + uc_pdata->ramp_delay); + } + + return ret; } /* @@ -107,6 +132,7 @@ int regulator_set_enable(struct udevice *dev, bool enable) { const struct dm_regulator_ops *ops = dev_get_driver_ops(dev); struct dm_regulator_uclass_platdata *uc_pdata; + int ret, old_enable = 0; if (!ops || !ops->set_enable) return -ENOSYS; @@ -115,7 +141,22 @@ int regulator_set_enable(struct udevice *dev, bool enable) if (!enable && uc_pdata->always_on) return -EACCES; - return ops->set_enable(dev, enable); + if (uc_pdata->ramp_delay) + old_enable = regulator_get_enable(dev); + + ret = ops->set_enable(dev, enable); + if (!ret) { + if (uc_pdata->ramp_delay && !old_enable && enable) { + int uV = regulator_get_value(dev); + + if (uV > 0) { + regulator_set_value_ramp_delay(dev, 0, uV, + uc_pdata->ramp_delay); + } + } + } + + return ret; } int regulator_set_enable_if_allowed(struct udevice *dev, bool enable) @@ -335,6 +376,8 @@ static int regulator_pre_probe(struct udevice *dev) -ENODATA); uc_pdata->always_on = dev_read_bool(dev, "regulator-always-on"); uc_pdata->boot_on = dev_read_bool(dev, "regulator-boot-on"); + uc_pdata->ramp_delay = dev_read_u32_default(dev, "regulator-ramp-delay", + 0); /* Those values are optional (-ENODATA if unset) */ if ((uc_pdata->min_uV != -ENODATA) && diff --git a/include/power/regulator.h b/include/power/regulator.h index 314160a894b7..6c6e2cd4f996 100644 --- a/include/power/regulator.h +++ b/include/power/regulator.h @@ -150,6 +150,7 @@ enum regulator_flag { * @always_on* - bool type, true or false * @boot_on* - bool type, true or false * TODO(sjg@chromium.org): Consider putting the above two into @flags + * @ramp_delay - Time to settle down after voltage change (unit: uV/us) * @flags: - flags value (see REGULATOR_FLAG_...) * @name** - fdt regulator name - should be taken from the device tree * ctrl_reg: - Control register offset used to enable/disable regulator @@ -169,6 +170,7 @@ struct dm_regulator_uclass_platdata { int max_uV; int min_uA; int max_uA; + unsigned int ramp_delay; bool always_on; bool boot_on; const char *name;