diff options
Diffstat (limited to 'drivers/thermal/broadcom/bcm2711_thermal.c')
-rw-r--r-- | drivers/thermal/broadcom/bcm2711_thermal.c | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/drivers/thermal/broadcom/bcm2711_thermal.c b/drivers/thermal/broadcom/bcm2711_thermal.c new file mode 100644 index 000000000..7b536c8a5 --- /dev/null +++ b/drivers/thermal/broadcom/bcm2711_thermal.c @@ -0,0 +1,120 @@ +// 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(void *data, int *temp) +{ + struct bcm2711_thermal_priv *priv = data; + int slope = thermal_zone_get_slope(priv->thermal); + int offset = thermal_zone_get_offset(priv->thermal); + 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_of_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_zone_of_sensor_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; + + thermal->tzp->no_hwmon = false; + ret = thermal_add_hwmon_sysfs(thermal); + if (ret) + return ret; + + return 0; +} + +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"); |