From patchwork Wed Jan 10 22:30:44 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Enric Balletbo i Serra X-Patchwork-Id: 858599 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=devicetree-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3zH3fB1slJz9s4s for ; Thu, 11 Jan 2018 09:32:02 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752813AbeAJWbq (ORCPT ); Wed, 10 Jan 2018 17:31:46 -0500 Received: from bhuna.collabora.co.uk ([46.235.227.227]:36972 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752224AbeAJWa5 (ORCPT ); Wed, 10 Jan 2018 17:30:57 -0500 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: eballetbo) with ESMTPSA id 73CDC27380C From: Enric Balletbo i Serra To: Daniel Thompson , Doug Anderson , Pavel Machek , Rob Herring Cc: Jingoo Han , Richard Purdie , Jacek Anaszewski , Brian Norris , Guenter Roeck , Lee Jones , Alexandru Stan , linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/4] dt-bindings: pwm-backlight: add a num-interpolation-steps property. Date: Wed, 10 Jan 2018 23:30:44 +0100 Message-Id: <20180110223046.17696-3-enric.balletbo@collabora.com> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20180110223046.17696-1-enric.balletbo@collabora.com> References: <20180110223046.17696-1-enric.balletbo@collabora.com> Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The num-interpolated-steps property specifies the number of interpolated steps between each value of brightness-level table. This is useful for high resolution PWMs to not have to list out every possible value in the brightness-level array. Signed-off-by: Enric Balletbo i Serra --- .../bindings/leds/backlight/pwm-backlight.txt | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt b/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt index 310810906613..605432c910c5 100644 --- a/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt +++ b/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt @@ -21,6 +21,11 @@ Optional properties: and enabling the backlight using GPIO. - pwm-off-delay-ms: Delay in ms between disabling the backlight using GPIO and setting PWM value to 0. + - num-interpolated-steps: Number of interpolated steps between each value + of brightness-levels table. This way a high + resolution pwm duty cycle can be used without + having to list out every possible value in the + brightness-level array. [0]: Documentation/devicetree/bindings/pwm/pwm.txt [1]: Documentation/devicetree/bindings/gpio/gpio.txt @@ -39,3 +44,19 @@ Example: post-pwm-on-delay-ms = <10>; pwm-off-delay-ms = <10>; }; + +Example using num-interpolation-steps: + + backlight { + compatible = "pwm-backlight"; + pwms = <&pwm 0 5000000>; + + brightness-levels = <0 65535>; + num-interpolated-steps = <4096>; + default-brightness-level = <6>; + + power-supply = <&vdd_bl_reg>; + enable-gpios = <&gpio 58 0>; + post-pwm-on-delay-ms = <10>; + pwm-off-delay-ms = <10>; + }; From patchwork Wed Jan 10 22:30:46 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Enric Balletbo i Serra X-Patchwork-Id: 858597 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=devicetree-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3zH3dt0NBHz9s4s for ; Thu, 11 Jan 2018 09:31:46 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752423AbeAJWbA (ORCPT ); Wed, 10 Jan 2018 17:31:00 -0500 Received: from bhuna.collabora.co.uk ([46.235.227.227]:36972 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752096AbeAJWa7 (ORCPT ); Wed, 10 Jan 2018 17:30:59 -0500 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: eballetbo) with ESMTPSA id 608AC2701FF From: Enric Balletbo i Serra To: Daniel Thompson , Doug Anderson , Pavel Machek , Rob Herring Cc: Jingoo Han , Richard Purdie , Jacek Anaszewski , Brian Norris , Guenter Roeck , Lee Jones , Alexandru Stan , linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 4/4] dt-bindings: pwm-backlight: move brightness-levels to optional. Date: Wed, 10 Jan 2018 23:30:46 +0100 Message-Id: <20180110223046.17696-5-enric.balletbo@collabora.com> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20180110223046.17696-1-enric.balletbo@collabora.com> References: <20180110223046.17696-1-enric.balletbo@collabora.com> Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The patch 'backlight: pwm_bl: compute brightness of LED linearly to human eye' introduced a default brightness-levels table that is used when brightness-levels is not availablel in the dts so move move brightness-levels and default-brightness-level to be optional. Signed-off-by: Enric Balletbo i Serra Reviewed-by: Rob Herring --- .../devicetree/bindings/leds/backlight/pwm-backlight.txt | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt b/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt index 605432c910c5..3d5a148bd66d 100644 --- a/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt +++ b/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt @@ -3,13 +3,6 @@ pwm-backlight bindings Required properties: - compatible: "pwm-backlight" - pwms: OF device-tree PWM specification (see PWM binding[0]) - - brightness-levels: Array of distinct brightness levels. Typically these - are in the range from 0 to 255, but any range starting at 0 will do. - The actual brightness level (PWM duty cycle) will be interpolated - from these values. 0 means a 0% duty cycle (darkest/off), while the - last value in the array represents a 100% duty cycle (brightest). - - default-brightness-level: the default brightness level (index into the - array defined by the "brightness-levels" property) - power-supply: regulator for supply voltage Optional properties: @@ -21,6 +14,14 @@ Optional properties: and enabling the backlight using GPIO. - pwm-off-delay-ms: Delay in ms between disabling the backlight using GPIO and setting PWM value to 0. + - brightness-levels: Array of distinct brightness levels. Typically these + are in the range from 0 to 255, but any range starting at + 0 will do. The actual brightness level (PWM duty cycle) + will be interpolated from these values. 0 means a 0% duty + cycle (darkest/off), while the last value in the array + represents a 100% duty cycle (brightest). + - default-brightness-level: The default brightness level (index into the + array defined by the "brightness-levels" property). - num-interpolated-steps: Number of interpolated steps between each value of brightness-levels table. This way a high resolution pwm duty cycle can be used without