From patchwork Sat Feb 9 22:54:07 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Krzysztof Kozlowski X-Patchwork-Id: 1039307 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="L1pK9FtY"; dkim-atps=neutral Received: from lists.denx.de (dione.denx.de [81.169.180.215]) by ozlabs.org (Postfix) with ESMTP id 43xnVw30ssz9s5c for ; Sun, 10 Feb 2019 09:57:12 +1100 (AEDT) Received: by lists.denx.de (Postfix, from userid 105) id DB997C22051; Sat, 9 Feb 2019 22:56:01 +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=KHOP_BIG_TO_CC, 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 C9435C22033; Sat, 9 Feb 2019 22:55:22 +0000 (UTC) Received: by lists.denx.de (Postfix, from userid 105) id B27C7C22027; Sat, 9 Feb 2019 22:54:40 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by lists.denx.de (Postfix) with ESMTPS id 5BD17C2202A for ; Sat, 9 Feb 2019 22:54:36 +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 205182192C; Sat, 9 Feb 2019 22:54:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549752875; bh=MaDRMpeRYtmSsiyZCB/9Dib7e5vhZ6XlDh/E0b5g+10=; h=From:To:Subject:Date:In-Reply-To:References:From; b=L1pK9FtYIqlsVeOGRr7fNCmi+z5x9vmPbOX2zEYJaxcYJbePXv19VvNucWP3X4YOr HrzKZzs01p2656qF2+arpQWlYjf8VDm1znH+bI5TNSb9xwQxj6ROpprFSM1c1507SV DwZNEWAPYDKUi68nfGJvh2puoFIUc3EnJ9tA0QuM= From: Krzysztof Kozlowski To: Albert Aribaud , Jaehoon Chung , Krzysztof Kozlowski , Simon Glass , Minkyu Kang , Marek Szyprowski , Lukasz Majewski , Dirk Meul , Patrice Chotard , Felix Brack , Jack Mitchell , Patrick Delaunay , Lokesh Vutla , u-boot@lists.denx.de Date: Sat, 9 Feb 2019 23:54:07 +0100 Message-Id: <20190209225411.32756-5-krzk@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190209225411.32756-1-krzk@kernel.org> References: <20190209225411.32756-1-krzk@kernel.org> Subject: [U-Boot] [RFT 4/8] 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 --- drivers/power/regulator/regulator-uclass.c | 45 +++++++++++++++++++++- include/power/regulator.h | 2 + 2 files changed, 45 insertions(+), 2 deletions(-) diff --git a/drivers/power/regulator/regulator-uclass.c b/drivers/power/regulator/regulator-uclass.c index 39e46279d533..4119f244c74b 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_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; uc_pdata = dev_get_uclass_platdata(dev); if (uc_pdata->min_uV != -ENODATA && uV < uc_pdata->min_uV) @@ -49,7 +61,18 @@ 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) + old_uV = regulator_get_value(dev); + + ret = ops->set_value(dev, uV); + + if (!ret) { + if (uc_pdata->ramp_delay && old_uV > 0) + regulator_set_value_delay(dev, old_uV, uV, + uc_pdata->ramp_delay); + } + + return ret; } /* @@ -107,6 +130,7 @@ 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 +139,22 @@ int regulator_set_enable(struct udevice *dev, bool enable) if (!enable && uc_pdata->always_on) return 0; - 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) { + int uV = regulator_get_value(dev); + + if (uV > 0) { + regulator_set_value_delay(dev, 0, uV, + uc_pdata->ramp_delay); + } + } + } + + return ret; } int regulator_get_mode(struct udevice *dev) @@ -324,6 +363,8 @@ 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 5318ab3acece..c13fa1f336e5 100644 --- a/include/power/regulator.h +++ b/include/power/regulator.h @@ -149,6 +149,7 @@ enum regulator_flag { * @max_uA* - maximum amperage (micro Amps) * @always_on* - bool type, true or false * @boot_on* - bool type, true or false + * @ramp_delay - Time to settle down after voltage change (unit: uV/us) * TODO(sjg@chromium.org): Consider putting the above two into @flags * @flags: - flags value (see REGULATOR_FLAG_...) * @name** - fdt regulator name - should be taken from the device tree @@ -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;