diff options
Diffstat (limited to 'drivers/platform/x86/gpd-pocket-fan.c')
| -rw-r--r-- | drivers/platform/x86/gpd-pocket-fan.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/drivers/platform/x86/gpd-pocket-fan.c b/drivers/platform/x86/gpd-pocket-fan.c new file mode 100644 index 000000000000..c6f4d89b1437 --- /dev/null +++ b/drivers/platform/x86/gpd-pocket-fan.c @@ -0,0 +1,193 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * GPD Pocket fan controller driver + * + * Copyright (C) 2017 Hans de Goede <hdegoede@redhat.com> + */ + +#include <linux/acpi.h> +#include <linux/gpio/consumer.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/platform_device.h> +#include <linux/thermal.h> +#include <linux/workqueue.h> + +static int temp_limits[3] = { 55000, 60000, 65000 }; +module_param_array(temp_limits, int, NULL, 0444); +MODULE_PARM_DESC(temp_limits, + "Milli-celcius values above which the fan speed increases"); + +static int hysteresis = 3000; +module_param(hysteresis, int, 0444); +MODULE_PARM_DESC(hysteresis, + "Hysteresis in milli-celcius before lowering the fan speed"); + +struct gpd_pocket_fan_data { + struct device *dev; + struct thermal_zone_device *dts0; + struct thermal_zone_device *dts1; + struct gpio_desc *gpio0; + struct gpio_desc *gpio1; + struct delayed_work work; + int last_speed; +}; + +static void gpd_pocket_fan_set_speed(struct gpd_pocket_fan_data *fan, int speed) +{ + if (speed == fan->last_speed) + return; + + gpiod_direction_output(fan->gpio0, !!(speed & 1)); + gpiod_direction_output(fan->gpio1, !!(speed & 2)); + + fan->last_speed = speed; +} + +static void gpd_pocket_fan_worker(struct work_struct *work) +{ + struct gpd_pocket_fan_data *fan = + container_of(work, struct gpd_pocket_fan_data, work.work); + int t0, t1, temp, speed, i; + + if (thermal_zone_get_temp(fan->dts0, &t0) || + thermal_zone_get_temp(fan->dts1, &t1)) { + dev_warn(fan->dev, "Error getting temperature\n"); + queue_delayed_work(system_wq, &fan->work, + msecs_to_jiffies(1000)); + return; + } + + temp = max(t0, t1); + + speed = fan->last_speed; + + /* Determine minimum speed */ + for (i = 0; i < ARRAY_SIZE(temp_limits); i++) { + if (temp < temp_limits[i]) + break; + } + if (speed < i) + speed = i; + + /* Use hysteresis before lowering speed again */ + for (i = 0; i < ARRAY_SIZE(temp_limits); i++) { + if (temp <= (temp_limits[i] - hysteresis)) + break; + } + if (speed > i) + speed = i; + + if (fan->last_speed <= 0 && speed) + speed = 3; /* kick start motor */ + + gpd_pocket_fan_set_speed(fan, speed); + + /* When mostly idle (low temp/speed), slow down the poll interval. */ + queue_delayed_work(system_wq, &fan->work, + msecs_to_jiffies(4000 / (speed + 1))); +} + +static void gpd_pocket_fan_force_update(struct gpd_pocket_fan_data *fan) +{ + fan->last_speed = -1; + mod_delayed_work(system_wq, &fan->work, 0); +} + +static int gpd_pocket_fan_probe(struct platform_device *pdev) +{ + struct gpd_pocket_fan_data *fan; + int i; + + for (i = 0; i < ARRAY_SIZE(temp_limits); i++) { + if (temp_limits[i] < 40000 || temp_limits[i] > 70000) { + dev_err(&pdev->dev, "Invalid temp-limit %d (must be between 40000 and 70000)\n", + temp_limits[i]); + return -EINVAL; + } + } + if (hysteresis < 1000 || hysteresis > 10000) { + dev_err(&pdev->dev, "Invalid hysteresis %d (must be between 1000 and 10000)\n", + hysteresis); + return -EINVAL; + } + + fan = devm_kzalloc(&pdev->dev, sizeof(*fan), GFP_KERNEL); + if (!fan) + return -ENOMEM; + + fan->dev = &pdev->dev; + INIT_DELAYED_WORK(&fan->work, gpd_pocket_fan_worker); + + /* Note this returns a "weak" reference which we don't need to free */ + fan->dts0 = thermal_zone_get_zone_by_name("soc_dts0"); + if (IS_ERR(fan->dts0)) + return -EPROBE_DEFER; + + fan->dts1 = thermal_zone_get_zone_by_name("soc_dts1"); + if (IS_ERR(fan->dts1)) + return -EPROBE_DEFER; + + fan->gpio0 = devm_gpiod_get_index(fan->dev, NULL, 0, GPIOD_ASIS); + if (IS_ERR(fan->gpio0)) + return PTR_ERR(fan->gpio0); + + fan->gpio1 = devm_gpiod_get_index(fan->dev, NULL, 1, GPIOD_ASIS); + if (IS_ERR(fan->gpio1)) + return PTR_ERR(fan->gpio1); + + gpd_pocket_fan_force_update(fan); + + platform_set_drvdata(pdev, fan); + return 0; +} + +static int gpd_pocket_fan_remove(struct platform_device *pdev) +{ + struct gpd_pocket_fan_data *fan = platform_get_drvdata(pdev); + + cancel_delayed_work_sync(&fan->work); + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int gpd_pocket_fan_suspend(struct device *dev) +{ + struct gpd_pocket_fan_data *fan = dev_get_drvdata(dev); + + gpd_pocket_fan_set_speed(fan, 0); + return 0; +} + +static int gpd_pocket_fan_resume(struct device *dev) +{ + struct gpd_pocket_fan_data *fan = dev_get_drvdata(dev); + + gpd_pocket_fan_force_update(fan); + return 0; +} +#endif +static SIMPLE_DEV_PM_OPS(gpd_pocket_fan_pm_ops, + gpd_pocket_fan_suspend, + gpd_pocket_fan_resume); + +static struct acpi_device_id gpd_pocket_fan_acpi_match[] = { + { "FAN02501" }, + {}, +}; +MODULE_DEVICE_TABLE(acpi, gpd_pocket_fan_acpi_match); + +static struct platform_driver gpd_pocket_fan_driver = { + .probe = gpd_pocket_fan_probe, + .remove = gpd_pocket_fan_remove, + .driver = { + .name = "gpd_pocket_fan", + .acpi_match_table = gpd_pocket_fan_acpi_match, + .pm = &gpd_pocket_fan_pm_ops, + }, +}; + +module_platform_driver(gpd_pocket_fan_driver); +MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com"); +MODULE_DESCRIPTION("GPD pocket fan driver"); +MODULE_LICENSE("GPL"); |