From 5772717e59b9fbdc9e97da606dd69a75174f8101 Mon Sep 17 00:00:00 2001 From: Neil Armstrong Date: Wed, 24 Jun 2020 18:15:27 +0200 Subject: [PATCH] thermal: Add support for the MCU controlled FAN on Khadas boards The new Khadas VIM2 and VIM3 boards controls the cooling fan via the on-board microcontroller. This implements the FAN control as thermal devices and as cell of the Khadas MCU MFD driver. Signed-off-by: Neil Armstrong Reviewed-by: Amit Kucheria Acked-by: Daniel Lezcano Signed-off-by: Lee Jones --- drivers/thermal/Kconfig | 11 +++ drivers/thermal/Makefile | 1 + drivers/thermal/khadas_mcu_fan.c | 162 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 174 insertions(+) create mode 100644 drivers/thermal/khadas_mcu_fan.c diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 3eb2348e5242..0125561488c9 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -500,4 +500,15 @@ config SPRD_THERMAL help Support for the Spreadtrum thermal sensor driver in the Linux thermal framework. + +config KHADAS_MCU_FAN_THERMAL + tristate "Khadas MCU controller FAN cooling support" + depends on OF || COMPILE_TEST + depends on MFD_KHADAS_MCU + select MFD_CORE + select REGMAP + help + If you say yes here you get support for the FAN controlled + by the Microcontroller found on the Khadas VIM boards. + endif diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 0c8b84a09b9a..4b6aabaa7e31 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -61,3 +61,4 @@ obj-$(CONFIG_ZX2967_THERMAL) += zx2967_thermal.o obj-$(CONFIG_UNIPHIER_THERMAL) += uniphier_thermal.o obj-$(CONFIG_AMLOGIC_THERMAL) += amlogic_thermal.o obj-$(CONFIG_SPRD_THERMAL) += sprd_thermal.o +obj-$(CONFIG_KHADAS_MCU_FAN_THERMAL) += khadas_mcu_fan.o diff --git a/drivers/thermal/khadas_mcu_fan.c b/drivers/thermal/khadas_mcu_fan.c new file mode 100644 index 000000000000..9eadd2d6413e --- /dev/null +++ b/drivers/thermal/khadas_mcu_fan.c @@ -0,0 +1,162 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Khadas MCU Controlled FAN driver + * + * Copyright (C) 2020 BayLibre SAS + * Author(s): Neil Armstrong + */ + +#include +#include +#include +#include +#include +#include +#include + +#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; + thermal_cdev_update(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 "); +MODULE_DESCRIPTION("Khadas MCU FAN driver"); +MODULE_LICENSE("GPL"); -- 2.11.0