diff options
Diffstat (limited to 'drivers/thermal/armada_thermal.c')
| -rw-r--r-- | drivers/thermal/armada_thermal.c | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/drivers/thermal/armada_thermal.c b/drivers/thermal/armada_thermal.c new file mode 100644 index 000000000000..5b4d75fd7b49 --- /dev/null +++ b/drivers/thermal/armada_thermal.c @@ -0,0 +1,232 @@ +/* + * Marvell Armada 370/XP thermal sensor driver + * + * Copyright (C) 2013 Marvell + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ +#include <linux/device.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/of.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/of_device.h> +#include <linux/thermal.h> + +#define THERMAL_VALID_OFFSET 9 +#define THERMAL_VALID_MASK 0x1 +#define THERMAL_TEMP_OFFSET 10 +#define THERMAL_TEMP_MASK 0x1ff + +/* Thermal Manager Control and Status Register */ +#define PMU_TDC0_SW_RST_MASK (0x1 << 1) +#define PMU_TM_DISABLE_OFFS 0 +#define PMU_TM_DISABLE_MASK (0x1 << PMU_TM_DISABLE_OFFS) +#define PMU_TDC0_REF_CAL_CNT_OFFS 11 +#define PMU_TDC0_REF_CAL_CNT_MASK (0x1ff << PMU_TDC0_REF_CAL_CNT_OFFS) +#define PMU_TDC0_OTF_CAL_MASK (0x1 << 30) +#define PMU_TDC0_START_CAL_MASK (0x1 << 25) + +struct armada_thermal_ops; + +/* Marvell EBU Thermal Sensor Dev Structure */ +struct armada_thermal_priv { + void __iomem *sensor; + void __iomem *control; + struct armada_thermal_ops *ops; +}; + +struct armada_thermal_ops { + /* Initialize the sensor */ + void (*init_sensor)(struct armada_thermal_priv *); + + /* Test for a valid sensor value (optional) */ + bool (*is_valid)(struct armada_thermal_priv *); +}; + +static void armadaxp_init_sensor(struct armada_thermal_priv *priv) +{ + unsigned long reg; + + reg = readl_relaxed(priv->control); + reg |= PMU_TDC0_OTF_CAL_MASK; + writel(reg, priv->control); + + /* Reference calibration value */ + reg &= ~PMU_TDC0_REF_CAL_CNT_MASK; + reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS); + writel(reg, priv->control); + + /* Reset the sensor */ + reg = readl_relaxed(priv->control); + writel((reg | PMU_TDC0_SW_RST_MASK), priv->control); + + writel(reg, priv->control); + + /* Enable the sensor */ + reg = readl_relaxed(priv->sensor); + reg &= ~PMU_TM_DISABLE_MASK; + writel(reg, priv->sensor); +} + +static void armada370_init_sensor(struct armada_thermal_priv *priv) +{ + unsigned long reg; + + reg = readl_relaxed(priv->control); + reg |= PMU_TDC0_OTF_CAL_MASK; + writel(reg, priv->control); + + /* Reference calibration value */ + reg &= ~PMU_TDC0_REF_CAL_CNT_MASK; + reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS); + writel(reg, priv->control); + + reg &= ~PMU_TDC0_START_CAL_MASK; + writel(reg, priv->control); + + mdelay(10); +} + +static bool armada_is_valid(struct armada_thermal_priv *priv) +{ + unsigned long reg = readl_relaxed(priv->sensor); + + return (reg >> THERMAL_VALID_OFFSET) & THERMAL_VALID_MASK; +} + +static int armada_get_temp(struct thermal_zone_device *thermal, + unsigned long *temp) +{ + struct armada_thermal_priv *priv = thermal->devdata; + unsigned long reg; + + /* Valid check */ + if (priv->ops->is_valid && !priv->ops->is_valid(priv)) { + dev_err(&thermal->device, + "Temperature sensor reading not valid\n"); + return -EIO; + } + + reg = readl_relaxed(priv->sensor); + reg = (reg >> THERMAL_TEMP_OFFSET) & THERMAL_TEMP_MASK; + *temp = (3153000000UL - (10000000UL*reg)) / 13825; + return 0; +} + +static struct thermal_zone_device_ops ops = { + .get_temp = armada_get_temp, +}; + +static const struct armada_thermal_ops armadaxp_ops = { + .init_sensor = armadaxp_init_sensor, +}; + +static const struct armada_thermal_ops armada370_ops = { + .is_valid = armada_is_valid, + .init_sensor = armada370_init_sensor, +}; + +static const struct of_device_id armada_thermal_id_table[] = { + { + .compatible = "marvell,armadaxp-thermal", + .data = &armadaxp_ops, + }, + { + .compatible = "marvell,armada370-thermal", + .data = &armada370_ops, + }, + { + /* sentinel */ + }, +}; +MODULE_DEVICE_TABLE(of, armada_thermal_id_table); + +static int armada_thermal_probe(struct platform_device *pdev) +{ + struct thermal_zone_device *thermal; + const struct of_device_id *match; + struct armada_thermal_priv *priv; + struct resource *res; + + match = of_match_device(armada_thermal_id_table, &pdev->dev); + if (!match) + return -ENODEV; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "Failed to get platform resource\n"); + return -ENODEV; + } + + priv->sensor = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(priv->sensor)) + return PTR_ERR(priv->sensor); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + if (!res) { + dev_err(&pdev->dev, "Failed to get platform resource\n"); + return -ENODEV; + } + + priv->control = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(priv->control)) + return PTR_ERR(priv->control); + + priv->ops = (struct armada_thermal_ops *)match->data; + priv->ops->init_sensor(priv); + + thermal = thermal_zone_device_register("armada_thermal", 0, 0, + priv, &ops, NULL, 0, 0); + if (IS_ERR(thermal)) { + dev_err(&pdev->dev, + "Failed to register thermal zone device\n"); + return PTR_ERR(thermal); + } + + platform_set_drvdata(pdev, thermal); + + return 0; +} + +static int armada_thermal_exit(struct platform_device *pdev) +{ + struct thermal_zone_device *armada_thermal = + platform_get_drvdata(pdev); + + thermal_zone_device_unregister(armada_thermal); + platform_set_drvdata(pdev, NULL); + + return 0; +} + +static struct platform_driver armada_thermal_driver = { + .probe = armada_thermal_probe, + .remove = armada_thermal_exit, + .driver = { + .name = "armada_thermal", + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(armada_thermal_id_table), + }, +}; + +module_platform_driver(armada_thermal_driver); + +MODULE_AUTHOR("Ezequiel Garcia <ezequiel.garcia@free-electrons.com>"); +MODULE_DESCRIPTION("Armada 370/XP thermal driver"); +MODULE_LICENSE("GPL v2"); |