| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/of_address.h> |
| #include <linux/platform_device.h> |
| #include <linux/thermal.h> |
| |
| struct thermal_mmio { |
| void __iomem *mmio_base; |
| u32 (*read_mmio)(void __iomem *mmio_base); |
| u32 mask; |
| int factor; |
| }; |
| |
| static u32 thermal_mmio_readb(void __iomem *mmio_base) |
| { |
| return readb(mmio_base); |
| } |
| |
| static int thermal_mmio_get_temperature(struct thermal_zone_device *tz, int *temp) |
| { |
| int t; |
| struct thermal_mmio *sensor = tz->devdata; |
| |
| t = sensor->read_mmio(sensor->mmio_base) & sensor->mask; |
| t *= sensor->factor; |
| |
| *temp = t; |
| |
| return 0; |
| } |
| |
| static const struct thermal_zone_device_ops thermal_mmio_ops = { |
| .get_temp = thermal_mmio_get_temperature, |
| }; |
| |
| static int thermal_mmio_probe(struct platform_device *pdev) |
| { |
| struct thermal_mmio *sensor; |
| int (*sensor_init_func)(struct platform_device *pdev, |
| struct thermal_mmio *sensor); |
| struct thermal_zone_device *thermal_zone; |
| int ret; |
| int temperature; |
| |
| sensor = devm_kzalloc(&pdev->dev, sizeof(*sensor), GFP_KERNEL); |
| if (!sensor) |
| return -ENOMEM; |
| |
| sensor->mmio_base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); |
| if (IS_ERR(sensor->mmio_base)) |
| return PTR_ERR(sensor->mmio_base); |
| |
| sensor_init_func = device_get_match_data(&pdev->dev); |
| if (sensor_init_func) { |
| ret = sensor_init_func(pdev, sensor); |
| if (ret) { |
| dev_err(&pdev->dev, |
| "failed to initialize sensor (%d)\n", |
| ret); |
| return ret; |
| } |
| } |
| |
| thermal_zone = devm_thermal_of_zone_register(&pdev->dev, |
| 0, |
| sensor, |
| &thermal_mmio_ops); |
| if (IS_ERR(thermal_zone)) { |
| dev_err(&pdev->dev, |
| "failed to register sensor (%ld)\n", |
| PTR_ERR(thermal_zone)); |
| return PTR_ERR(thermal_zone); |
| } |
| |
| thermal_mmio_get_temperature(thermal_zone, &temperature); |
| dev_info(&pdev->dev, |
| "thermal mmio sensor %s registered, current temperature: %d\n", |
| pdev->name, temperature); |
| |
| return 0; |
| } |
| |
| static int al_thermal_init(struct platform_device *pdev, |
| struct thermal_mmio *sensor) |
| { |
| sensor->read_mmio = thermal_mmio_readb; |
| sensor->mask = 0xff; |
| sensor->factor = 1000; |
| |
| return 0; |
| } |
| |
| static const struct of_device_id thermal_mmio_id_table[] = { |
| { .compatible = "amazon,al-thermal", .data = al_thermal_init}, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(of, thermal_mmio_id_table); |
| |
| static struct platform_driver thermal_mmio_driver = { |
| .probe = thermal_mmio_probe, |
| .driver = { |
| .name = "thermal-mmio", |
| .of_match_table = thermal_mmio_id_table, |
| }, |
| }; |
| |
| module_platform_driver(thermal_mmio_driver); |
| |
| MODULE_AUTHOR("Talel Shenhar <talel@amazon.com>"); |
| MODULE_DESCRIPTION("Thermal MMIO Driver"); |
| MODULE_LICENSE("GPL v2"); |