162 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			162 lines
		
	
	
		
			3.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-or-later
 | |
| /*
 | |
|  * Khadas MCU Controlled FAN driver
 | |
|  *
 | |
|  * Copyright (C) 2020 BayLibre SAS
 | |
|  * Author(s): Neil Armstrong <narmstrong@baylibre.com>
 | |
|  */
 | |
| 
 | |
| #include <linux/module.h>
 | |
| #include <linux/of.h>
 | |
| #include <linux/platform_device.h>
 | |
| #include <linux/mfd/khadas-mcu.h>
 | |
| #include <linux/regmap.h>
 | |
| #include <linux/sysfs.h>
 | |
| #include <linux/thermal.h>
 | |
| 
 | |
| #define MAX_LEVEL 3
 | |
| 
 | |
| struct khadas_mcu_fan_ctx {
 | |
| 	struct khadas_mcu *mcu;
 | |
| 	unsigned int level;
 | |
| 	struct thermal_cooling_device *cdev;
 | |
| };
 | |
| 
 | |
| static int khadas_mcu_fan_set_level(struct khadas_mcu_fan_ctx *ctx,
 | |
| 				    unsigned int level)
 | |
| {
 | |
| 	int ret;
 | |
| 
 | |
| 	ret = regmap_write(ctx->mcu->regmap, KHADAS_MCU_CMD_FAN_STATUS_CTRL_REG,
 | |
| 			   level);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	ctx->level = level;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int khadas_mcu_fan_get_max_state(struct thermal_cooling_device *cdev,
 | |
| 					unsigned long *state)
 | |
| {
 | |
| 	*state = MAX_LEVEL;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int khadas_mcu_fan_get_cur_state(struct thermal_cooling_device *cdev,
 | |
| 					unsigned long *state)
 | |
| {
 | |
| 	struct khadas_mcu_fan_ctx *ctx = cdev->devdata;
 | |
| 
 | |
| 	*state = ctx->level;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int
 | |
| khadas_mcu_fan_set_cur_state(struct thermal_cooling_device *cdev,
 | |
| 			     unsigned long state)
 | |
| {
 | |
| 	struct khadas_mcu_fan_ctx *ctx = cdev->devdata;
 | |
| 
 | |
| 	if (state > MAX_LEVEL)
 | |
| 		return -EINVAL;
 | |
| 
 | |
| 	if (state == ctx->level)
 | |
| 		return 0;
 | |
| 
 | |
| 	return khadas_mcu_fan_set_level(ctx, state);
 | |
| }
 | |
| 
 | |
| static const struct thermal_cooling_device_ops khadas_mcu_fan_cooling_ops = {
 | |
| 	.get_max_state = khadas_mcu_fan_get_max_state,
 | |
| 	.get_cur_state = khadas_mcu_fan_get_cur_state,
 | |
| 	.set_cur_state = khadas_mcu_fan_set_cur_state,
 | |
| };
 | |
| 
 | |
| static int khadas_mcu_fan_probe(struct platform_device *pdev)
 | |
| {
 | |
| 	struct khadas_mcu *mcu = dev_get_drvdata(pdev->dev.parent);
 | |
| 	struct thermal_cooling_device *cdev;
 | |
| 	struct device *dev = &pdev->dev;
 | |
| 	struct khadas_mcu_fan_ctx *ctx;
 | |
| 	int ret;
 | |
| 
 | |
| 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
 | |
| 	if (!ctx)
 | |
| 		return -ENOMEM;
 | |
| 	ctx->mcu = mcu;
 | |
| 	platform_set_drvdata(pdev, ctx);
 | |
| 
 | |
| 	cdev = devm_thermal_of_cooling_device_register(dev->parent,
 | |
| 			dev->parent->of_node, "khadas-mcu-fan", ctx,
 | |
| 			&khadas_mcu_fan_cooling_ops);
 | |
| 	if (IS_ERR(cdev)) {
 | |
| 		ret = PTR_ERR(cdev);
 | |
| 		dev_err(dev, "Failed to register khadas-mcu-fan as cooling device: %d\n",
 | |
| 			ret);
 | |
| 		return ret;
 | |
| 	}
 | |
| 	ctx->cdev = cdev;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static void khadas_mcu_fan_shutdown(struct platform_device *pdev)
 | |
| {
 | |
| 	struct khadas_mcu_fan_ctx *ctx = platform_get_drvdata(pdev);
 | |
| 
 | |
| 	khadas_mcu_fan_set_level(ctx, 0);
 | |
| }
 | |
| 
 | |
| #ifdef CONFIG_PM_SLEEP
 | |
| static int khadas_mcu_fan_suspend(struct device *dev)
 | |
| {
 | |
| 	struct khadas_mcu_fan_ctx *ctx = dev_get_drvdata(dev);
 | |
| 	unsigned int level_save = ctx->level;
 | |
| 	int ret;
 | |
| 
 | |
| 	ret = khadas_mcu_fan_set_level(ctx, 0);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	ctx->level = level_save;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int khadas_mcu_fan_resume(struct device *dev)
 | |
| {
 | |
| 	struct khadas_mcu_fan_ctx *ctx = dev_get_drvdata(dev);
 | |
| 
 | |
| 	return khadas_mcu_fan_set_level(ctx, ctx->level);
 | |
| }
 | |
| #endif
 | |
| 
 | |
| static SIMPLE_DEV_PM_OPS(khadas_mcu_fan_pm, khadas_mcu_fan_suspend,
 | |
| 			 khadas_mcu_fan_resume);
 | |
| 
 | |
| static const struct platform_device_id khadas_mcu_fan_id_table[] = {
 | |
| 	{ .name = "khadas-mcu-fan-ctrl", },
 | |
| 	{},
 | |
| };
 | |
| MODULE_DEVICE_TABLE(platform, khadas_mcu_fan_id_table);
 | |
| 
 | |
| static struct platform_driver khadas_mcu_fan_driver = {
 | |
| 	.probe		= khadas_mcu_fan_probe,
 | |
| 	.shutdown	= khadas_mcu_fan_shutdown,
 | |
| 	.driver	= {
 | |
| 		.name		= "khadas-mcu-fan-ctrl",
 | |
| 		.pm		= &khadas_mcu_fan_pm,
 | |
| 	},
 | |
| 	.id_table	= khadas_mcu_fan_id_table,
 | |
| };
 | |
| 
 | |
| module_platform_driver(khadas_mcu_fan_driver);
 | |
| 
 | |
| MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
 | |
| MODULE_DESCRIPTION("Khadas MCU FAN driver");
 | |
| MODULE_LICENSE("GPL");
 |