From patchwork Mon Apr 4 11:48:40 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mason X-Patchwork-Id: 8740641 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id DAA50C0553 for ; Mon, 4 Apr 2016 11:48:58 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id BCC6A20272 for ; Mon, 4 Apr 2016 11:48:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8600220279 for ; Mon, 4 Apr 2016 11:48:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753890AbcDDLsy (ORCPT ); Mon, 4 Apr 2016 07:48:54 -0400 Received: from smtp2-g21.free.fr ([212.27.42.2]:55085 "EHLO smtp2-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753154AbcDDLsx (ORCPT ); Mon, 4 Apr 2016 07:48:53 -0400 Received: from [172.27.0.114] (unknown [83.142.147.193]) (Authenticated sender: slash.tmp) by smtp2-g21.free.fr (Postfix) with ESMTPSA id 816224B01B4; Mon, 4 Apr 2016 13:43:35 +0200 (CEST) Subject: Re: [PATCH v6] thermal: add temperature sensor support for tango SoC To: Eduardo Valentin Cc: linux-pm , Zhang Rui , Javi Merino , Viresh Kumar , Rob Herring , Mark Rutland , arm-soc References: <56D5C7FE.7010807@free.fr> <56D9AF4F.1010304@free.fr> <20160308214846.GA10950@localhost.localdomain> <56F84427.1000507@free.fr> <56F91A47.9060901@free.fr> <20160329020050.GA15721@localhost.localdomain> <56FACE0B.9060606@free.fr> <20160330000503.GA2625@localhost.localdomain> <56FBEE4F.3060106@free.fr> <56FD8582.80002@free.fr> <20160401015240.GB19409@localhost.localdomain> From: Mason Message-ID: <57025498.4080408@free.fr> Date: Mon, 4 Apr 2016 13:48:40 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:42.0) Gecko/20100101 Firefox/42.0 SeaMonkey/2.39 MIME-Version: 1.0 In-Reply-To: <20160401015240.GB19409@localhost.localdomain> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Spam-Status: No, score=-7.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Marc Gonzalez The Tango thermal driver provides support for the primitive temperature sensor embedded in Tango chips since the SMP8758. This sensor only generates a 1-bit signal to indicate whether the die temperature exceeds a programmable threshold. Signed-off-by: Marc Gonzalez --- CCing Rob and Mark for the DT parts --- Documentation/devicetree/bindings/thermal/tango-thermal.txt | 17 ++++ arch/arm/boot/dts/tango4-smp8758.dtsi | 16 ++++ drivers/thermal/Kconfig | 9 ++ drivers/thermal/Makefile | 1 + drivers/thermal/tango_thermal.c | 125 +++++++++++++++++++++++++++ 5 files changed, 168 insertions(+) diff --git a/Documentation/devicetree/bindings/thermal/tango-thermal.txt b/Documentation/devicetree/bindings/thermal/tango-thermal.txt new file mode 100644 index 000000000000..212198d4b937 --- /dev/null +++ b/Documentation/devicetree/bindings/thermal/tango-thermal.txt @@ -0,0 +1,17 @@ +* Tango Thermal + +The SMP8758 SoC includes 3 instances of this temperature sensor +(in the CPU, video decoder, and PCIe controller). + +Required properties: +- #thermal-sensor-cells: Should be 0 (see thermal.txt) +- compatible: "sigma,smp8758-thermal" +- reg: Address range of the thermal registers + +Example: + + cpu_temp: thermal@920100 { + #thermal-sensor-cells = <0>; + compatible = "sigma,smp8758-thermal"; + reg = <0x920100 12>; + }; diff --git a/arch/arm/boot/dts/tango4-smp8758.dtsi b/arch/arm/boot/dts/tango4-smp8758.dtsi index 7ed88ee629fb..44d57c02e934 100644 --- a/arch/arm/boot/dts/tango4-smp8758.dtsi +++ b/arch/arm/boot/dts/tango4-smp8758.dtsi @@ -28,4 +28,20 @@ , ; }; + + soc { + cpu_temp: thermal@920100 { + #thermal-sensor-cells = <0>; + compatible = "sigma,smp8758-thermal"; + reg = <0x920100 12>; + }; + }; + + thermal-zones { + cpu_thermal: cpu-thermal { + polling-delay-passive = <2003>; /* ms */ + polling-delay = <1009>; /* ms */ + thermal-sensors = <&cpu_temp>; + }; + }; }; diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 8cc4ac64a91c..4b0776797700 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -254,6 +254,15 @@ config ARMADA_THERMAL Enable this option if you want to have support for thermal management controller present in Armada 370 and Armada XP SoC. +config TANGO_THERMAL + tristate "Tango thermal management" + depends on ARCH_TANGO || COMPILE_TEST + help + Enable the Tango thermal driver, which supports the primitive + temperature sensor embedded in Tango chips since the SMP8758. + This sensor only generates a 1-bit signal to indicate whether + the die temperature exceeds a programmable threshold. + config TEGRA_SOCTHERM tristate "Tegra SOCTHERM thermal management" depends on ARCH_TEGRA diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index cfae6a654793..8bfea2b7e722 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -35,6 +35,7 @@ obj-y += samsung/ obj-$(CONFIG_DOVE_THERMAL) += dove_thermal.o obj-$(CONFIG_DB8500_THERMAL) += db8500_thermal.o obj-$(CONFIG_ARMADA_THERMAL) += armada_thermal.o +obj-$(CONFIG_TANGO_THERMAL) += tango_thermal.o obj-$(CONFIG_IMX_THERMAL) += imx_thermal.o obj-$(CONFIG_DB8500_CPUFREQ_COOLING) += db8500_cpufreq_cooling.o obj-$(CONFIG_INTEL_POWERCLAMP) += intel_powerclamp.o diff --git a/drivers/thermal/tango_thermal.c b/drivers/thermal/tango_thermal.c new file mode 100644 index 000000000000..4bb741662087 --- /dev/null +++ b/drivers/thermal/tango_thermal.c @@ -0,0 +1,125 @@ +#include +#include +#include +#include +#include + +/* + * According to a data sheet draft, "this temperature sensor uses a bandgap + * type of circuit to compare a voltage which has a negative temperature + * coefficient with a voltage that is proportional to absolute temperature. + * A resistor bank allows 41 different temperature thresholds to be selected + * and the logic output will then indicate whether the actual die temperature + * lies above or below the selected threshold." + */ + +#define TEMPSI_CMD 0 +#define TEMPSI_RES 4 +#define TEMPSI_CFG 8 + +#define CMD_OFF 0 +#define CMD_ON 1 +#define CMD_READ 2 + +#define IDX_MIN 15 +#define IDX_MAX 40 +#define CYCLE_COUNT 500 /* Result sampled when timer expires */ + +struct tango_thermal_priv { + struct thermal_zone_device *zone; + void __iomem *base; + int thresh_idx; +}; + +static bool temp_above_thresh(void __iomem *base, int thresh_idx) +{ + writel(CMD_READ | thresh_idx << 8, base + TEMPSI_CMD); + usleep_range(10, 20); + return readl(base + TEMPSI_RES); +} + +static int tango_get_temp(void *arg, int *res) +{ + struct tango_thermal_priv *priv = arg; + void __iomem *base = priv->base; + int idx = priv->thresh_idx; + + if (temp_above_thresh(base, idx)) { + /* Search upward by incrementing thresh_idx */ + while (idx < IDX_MAX && temp_above_thresh(base, ++idx)) + cpu_relax(); + idx = idx - 1; /* always return lower bound */ + } else { + /* Search downward by decrementing thresh_idx */ + while (idx > IDX_MIN && !temp_above_thresh(base, --idx)) + cpu_relax(); + } + + *res = (idx * 9 / 2 - 38) * 1000; /* millidegrees Celsius */ + priv->thresh_idx = idx; + + return 0; +} + +static const struct thermal_zone_of_device_ops ops = { + .get_temp = tango_get_temp, +}; + +static int tango_thermal_probe(struct platform_device *pdev) +{ + struct resource *res; + struct tango_thermal_priv *priv; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + writel(CMD_ON, priv->base + TEMPSI_CMD); + writel(CYCLE_COUNT, priv->base + TEMPSI_CFG); + + priv->zone = thermal_zone_of_sensor_register(&pdev->dev, 0, priv, &ops); + if (IS_ERR(priv->zone)) + return PTR_ERR(priv->zone); + + priv->thresh_idx = IDX_MIN; + platform_set_drvdata(pdev, priv); + + return 0; +} + +static int tango_thermal_remove(struct platform_device *pdev) +{ + struct tango_thermal_priv *priv = platform_get_drvdata(pdev); + + thermal_zone_of_sensor_unregister(&pdev->dev, priv->zone); + writel(CMD_OFF, priv->base + TEMPSI_CMD); + + return 0; +} + +static const struct of_device_id tango_sensor_ids[] = { + { + .compatible = "sigma,smp8758-thermal", + }, + { /* sentinel */ } +}; + +static struct platform_driver tango_thermal_driver = { + .probe = tango_thermal_probe, + .remove = tango_thermal_remove, + .driver = { + .name = "tango-thermal", + .of_match_table = tango_sensor_ids, + }, +}; + +module_platform_driver(tango_thermal_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Sigma Designs"); +MODULE_DESCRIPTION("Tango temperature sensor");