From patchwork Mon Jan 6 15:48:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Guido_G=C3=BCnther?= X-Patchwork-Id: 206109 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F1A9C33C9B for ; Mon, 6 Jan 2020 15:49:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7BCD8207FD for ; Mon, 6 Jan 2020 15:49:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726825AbgAFPtR (ORCPT ); Mon, 6 Jan 2020 10:49:17 -0500 Received: from honk.sigxcpu.org ([24.134.29.49]:41204 "EHLO honk.sigxcpu.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726858AbgAFPtJ (ORCPT ); Mon, 6 Jan 2020 10:49:09 -0500 Received: from localhost (localhost [127.0.0.1]) by honk.sigxcpu.org (Postfix) with ESMTP id BDD42FB03; Mon, 6 Jan 2020 16:49:07 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at honk.sigxcpu.org Received: from honk.sigxcpu.org ([127.0.0.1]) by localhost (honk.sigxcpu.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id dYybpWwB2XWK; Mon, 6 Jan 2020 16:49:05 +0100 (CET) Received: by bogon.sigxcpu.org (Postfix, from userid 1000) id 6208449D46; Mon, 6 Jan 2020 16:48:56 +0100 (CET) From: =?utf-8?q?Guido_G=C3=BCnther?= To: Jacek Anaszewski , Pavel Machek , Dan Murphy , Rob Herring , Mark Rutland , linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 6/6] leds: lm3692x: Allow to configure brigthness mode Date: Mon, 6 Jan 2020 16:48:55 +0100 Message-Id: <95aaa83d98c9b91b4d87f6bcbf5f18082f8a1639.1578324703.git.agx@sigxcpu.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: References: MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Brightness mode is currently hardcoded as linear in the driver. Make exponential mode configurable via DT. Signed-off-by: Guido Günther --- drivers/leds/leds-lm3692x.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/leds/leds-lm3692x.c b/drivers/leds/leds-lm3692x.c index 28a51aeb28de..933b786cfaec 100644 --- a/drivers/leds/leds-lm3692x.c +++ b/drivers/leds/leds-lm3692x.c @@ -239,8 +239,7 @@ static int lm3692x_leds_enable(struct lm3692x_led *led) if (ret) goto out; - ret = regmap_write(led->regmap, LM3692X_BRT_CTRL, - LM3692X_BL_ADJ_POL | LM3692X_RAMP_EN); + ret = regmap_write(led->regmap, LM3692X_BRT_CTRL, led->brightness_ctrl); if (ret) goto out; @@ -368,7 +367,12 @@ static enum led_brightness lm3692x_max_brightness(struct lm3692x_led *led, u32 max_code; /* see p.12 of LM36922 data sheet for brightness formula */ - max_code = ((max_cur * 1000) - 37806) / 12195; + if (led->brightness_ctrl & LM3692X_MAP_MODE_EXP) { + /* 228 =~ 1.0 / log2(1.003040572) */ + max_code = ilog2(max_cur/50) * 228; + } else { + max_code = ((max_cur * 1000) - 37806) / 12195; + } if (max_code > 0x7FF) max_code = 0x7FF; @@ -380,6 +384,7 @@ static int lm3692x_probe_dt(struct lm3692x_led *led) struct fwnode_handle *child = NULL; struct led_init_data init_data = {}; u32 ovp, max_cur; + bool exp_mode; int ret; led->enable_gpio = devm_gpiod_get_optional(&led->client->dev, @@ -430,6 +435,12 @@ static int lm3692x_probe_dt(struct lm3692x_led *led) } } + led->brightness_ctrl = LM3692X_BL_ADJ_POL | LM3692X_RAMP_EN; + exp_mode = device_property_read_bool(&led->client->dev, + "ti,brightness-mapping-exponential"); + if (exp_mode) + led->brightness_ctrl |= LM3692X_MAP_MODE_EXP; + child = device_get_next_child_node(&led->client->dev, child); if (!child) { dev_err(&led->client->dev, "No LED Child node\n");