From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mason Subject: [PATCH v5] thermal: add temperature sensor support for tango SoC Date: Mon, 28 Mar 2016 13:49:27 +0200 Message-ID: <56F91A47.9060901@free.fr> References: <56D5C7FE.7010807@free.fr> <56D9AF4F.1010304@free.fr> <20160308214846.GA10950@localhost.localdomain> <56F84427.1000507@free.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Return-path: Received: from smtp4-g21.free.fr ([212.27.42.4]:38120 "EHLO smtp4-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753536AbcC1Ltm (ORCPT ); Mon, 28 Mar 2016 07:49:42 -0400 In-Reply-To: <56F84427.1000507@free.fr> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Eduardo Valentin Cc: linux-pm , Zhang Rui , Javi Merino , Viresh Kumar , Arnd Bergmann , Mans Rullgard , Rob Herring From: Marc Gonzalez Since the SMP8758, Tango SoCs include several instances of a rudimentary bandgap temperature sensor. Signed-off-by: Marc Gonzalez --- Documentation/devicetree/bindings/thermal/tango-thermal.txt | 17 ++++ drivers/thermal/Kconfig | 7 ++ drivers/thermal/Makefile | 1 + drivers/thermal/tango_thermal.c | 114 +++++++++++++++++++++++++++ 4 files changed, 139 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..a203f7d60d35 --- /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: +- compatible: "sigma,smp8758-thermal" +- #thermal-sensor-cells: Should be 0 (see thermal.txt) +- reg: Address range of the thermal registers + +Example: + + cpu_temp: thermal@920100 { + compatible = "sigma,smp8758-thermal"; + #thermal-sensor-cells = <0>; + reg = <0x920100 12>; + }; diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index c37eedc35a24..b6bf563f05dc 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -260,6 +260,13 @@ 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 temperature sensor driver, which provides support + for the sensors used since the SMP8758. + config TEGRA_SOCTHERM tristate "Tegra SOCTHERM thermal management" depends on ARCH_TEGRA diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 8e9cbc3b5679..06387279883d 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..8c9abdf6a507 --- /dev/null +++ b/drivers/thermal/tango_thermal.c @@ -0,0 +1,114 @@ +#include +#include +#include +#include +#include + +#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 0 +#define IDX_MAX 40 +#define CYCLE_COUNT 5000 /* Time to wait before sampling the result */ + +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(thresh_idx << 8 | CMD_READ, base + TEMPSI_CMD); + usleep_range(100, 200); + 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)) { + /* Upward linear search, increment thresh */ + while (idx < IDX_MAX && temp_above_thresh(base, ++idx)) + cpu_relax(); + idx = idx - 1; /* always return lower bound */ + } else { + /* Downward linear search, decrement thresh */ + 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; + struct device *dev = &pdev->dev; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->base = devm_ioremap_resource(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(dev, 0, priv, &ops); + if (IS_ERR(priv->zone)) + return PTR_ERR(priv->zone); + + priv->thresh_idx = 15; /* arbitrary starting point */ + 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"); -- 2.7.4