// SPDX-License-Identifier: GPL-2.0+ /* * Broadcom AVS RO thermal sensor driver * * based on brcmstb_thermal * * Copyright (C) 2020 Stefan Wahren */ #include <linux/bitops.h> #include <linux/clk.h> #include <linux/device.h> #include <linux/err.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/mfd/syscon.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/of_device.h> #include <linux/regmap.h> #include <linux/thermal.h> #include "../thermal_hwmon.h" #define AVS_RO_TEMP_STATUS 0x200 #define AVS_RO_TEMP_STATUS_VALID_MSK (BIT(16) | BIT(10)) #define AVS_RO_TEMP_STATUS_DATA_MSK GENMASK(9, 0) struct bcm2711_thermal_priv { struct regmap *regmap; struct thermal_zone_device *thermal; }; static int bcm2711_get_temp(struct thermal_zone_device *tz, int *temp) { struct bcm2711_thermal_priv *priv = thermal_zone_device_priv(tz); int slope = thermal_zone_get_slope(tz); int offset = thermal_zone_get_offset(tz); u32 val; int ret; ret = regmap_read(priv->regmap, AVS_RO_TEMP_STATUS, &val); if (ret) return ret; if (!(val & AVS_RO_TEMP_STATUS_VALID_MSK)) return -EIO; val &= AVS_RO_TEMP_STATUS_DATA_MSK; /* Convert a HW code to a temperature reading (millidegree celsius) */ *temp = slope * val + offset; return 0; } static const struct thermal_zone_device_ops bcm2711_thermal_of_ops = { .get_temp = bcm2711_get_temp, }; static const struct of_device_id bcm2711_thermal_id_table[] = { { .compatible = "brcm,bcm2711-thermal" }, {}, }; MODULE_DEVICE_TABLE(of, bcm2711_thermal_id_table); static int bcm2711_thermal_probe(struct platform_device *pdev) { struct thermal_zone_device *thermal; struct bcm2711_thermal_priv *priv; struct device *dev = &pdev->dev; struct device_node *parent; struct regmap *regmap; int ret; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; /* get regmap from syscon node */ parent = of_get_parent(dev->of_node); /* parent should be syscon node */ regmap = syscon_node_to_regmap(parent); of_node_put(parent); if (IS_ERR(regmap)) { ret = PTR_ERR(regmap); dev_err(dev, "failed to get regmap: %d\n", ret); return ret; } priv->regmap = regmap; thermal = devm_thermal_of_zone_register(dev, 0, priv, &bcm2711_thermal_of_ops); if (IS_ERR(thermal)) { ret = PTR_ERR(thermal); dev_err(dev, "could not register sensor: %d\n", ret); return ret; } priv->thermal = thermal; return thermal_add_hwmon_sysfs(thermal); } static struct platform_driver bcm2711_thermal_driver = { .probe = bcm2711_thermal_probe, .driver = { .name = "bcm2711_thermal", .of_match_table = bcm2711_thermal_id_table, }, }; module_platform_driver(bcm2711_thermal_driver); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Stefan Wahren"); MODULE_DESCRIPTION("Broadcom AVS RO thermal sensor driver");