Allow gpio-fan to be used as thermal cooling device for platforms that use GPIO maps to control fans.
Signed-off-by: Nishanth Menon <[email protected]> --- Based on v3.19-rc3 .../devicetree/bindings/gpio/gpio-fan.txt | 14 +++ drivers/hwmon/gpio-fan.c | 93 ++++++++++++++++++-- 2 files changed, 100 insertions(+), 7 deletions(-) diff --git a/Documentation/devicetree/bindings/gpio/gpio-fan.txt b/Documentation/devicetree/bindings/gpio/gpio-fan.txt index 2dd457a3469a..046f2f400dbb 100644 --- a/Documentation/devicetree/bindings/gpio/gpio-fan.txt +++ b/Documentation/devicetree/bindings/gpio/gpio-fan.txt @@ -11,6 +11,9 @@ Required properties: Optional properties: - alarm-gpios: This pin going active indicates something is wrong with the fan, and a udev event will be fired. +- cooling-cells: If used as a cooling device, must be <2> + Also see: Documentation/devicetree/bindings/thermal/thermal.txt + min and max states are derived from the speed-map of the fan. Examples: @@ -23,3 +26,14 @@ Examples: 6000 2>; alarm-gpios = <&gpio1 15 1>; }; + + gpio_fan_cool: gpio_fan { + compatible = "gpio-fan"; + gpios = <&gpio2 14 1 + &gpio2 13 1>; + gpio-fan,speed-map = <0 0 + 3000 1 + 6000 2>; + alarm-gpios = <&gpio1 15 1>; + #cooling-cells = <2>; /* min followed by max */ + }; diff --git a/drivers/hwmon/gpio-fan.c b/drivers/hwmon/gpio-fan.c index 36abf814b8c7..089914c4f574 100644 --- a/drivers/hwmon/gpio-fan.c +++ b/drivers/hwmon/gpio-fan.c @@ -34,10 +34,14 @@ #include <linux/of.h> #include <linux/of_platform.h> #include <linux/of_gpio.h> +#include <linux/thermal.h> + struct gpio_fan_data { struct platform_device *pdev; struct device *hwmon_dev; + /* Cooling device if any */ + struct thermal_cooling_device *cdev; struct mutex lock; /* lock GPIOs operations. */ int num_ctrl; unsigned *ctrl; @@ -387,12 +391,63 @@ static int fan_ctrl_init(struct gpio_fan_data *fan_data, return 0; } +static int gpio_fan_get_max_state(struct thermal_cooling_device *cdev, + unsigned long *state) +{ + struct gpio_fan_data *fan_data = cdev->devdata; + + if (!fan_data) + return -EINVAL; + + *state = fan_data->num_speed - 1; + return 0; +} + +static int gpio_fan_get_cur_state(struct thermal_cooling_device *cdev, + unsigned long *state) +{ + struct gpio_fan_data *fan_data = cdev->devdata; + int r; + + if (!fan_data) + return -EINVAL; + + r = get_fan_speed_index(fan_data); + if (r < 0) + return r; + + *state = r; + return 0; + +} + +static int gpio_fan_set_cur_state(struct thermal_cooling_device *cdev, + unsigned long state) +{ + struct gpio_fan_data *fan_data = cdev->devdata; + + if (!fan_data) + return -EINVAL; + + set_fan_speed(fan_data, state); + + return 0; +} + +static const struct thermal_cooling_device_ops gpio_fan_cooling_ops = { + .get_max_state = gpio_fan_get_max_state, + .get_cur_state = gpio_fan_get_cur_state, + .set_cur_state = gpio_fan_set_cur_state, + +}; + #ifdef CONFIG_OF_GPIO /* * Translate OpenFirmware node properties into platform_data */ static int gpio_fan_get_of_pdata(struct device *dev, - struct gpio_fan_platform_data *pdata) + struct gpio_fan_platform_data *pdata, + struct gpio_fan_data *fan_data) { struct device_node *node; struct gpio_fan_speed *speed; @@ -480,6 +535,12 @@ static int gpio_fan_get_of_pdata(struct device *dev, pdata->alarm = alarm; } + fan_data->cdev = thermal_of_cooling_device_register(node, "gpio-fan", + fan_data, + &gpio_fan_cooling_ops); + if (IS_ERR(fan_data->cdev)) + dev_dbg(dev, "gpio-fan has no valid cooling DT property\n"); + return 0; } @@ -495,6 +556,11 @@ static int gpio_fan_probe(struct platform_device *pdev) struct gpio_fan_data *fan_data; struct gpio_fan_platform_data *pdata = dev_get_platdata(&pdev->dev); + fan_data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_fan_data), + GFP_KERNEL); + if (!fan_data) + return -ENOMEM; + #ifdef CONFIG_OF_GPIO if (!pdata) { pdata = devm_kzalloc(&pdev->dev, @@ -503,20 +569,19 @@ static int gpio_fan_probe(struct platform_device *pdev) if (!pdata) return -ENOMEM; - err = gpio_fan_get_of_pdata(&pdev->dev, pdata); + err = gpio_fan_get_of_pdata(&pdev->dev, pdata, fan_data); if (err) return err; } #else /* CONFIG_OF_GPIO */ if (!pdata) return -EINVAL; + /* Optional cooling device register for non Device tree platforms */ + fan_data->cdev = thermal_cooling_device_register("gpio-fan", + fan_data, + &gpio_fan_cooling_ops); #endif /* CONFIG_OF_GPIO */ - fan_data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_fan_data), - GFP_KERNEL); - if (!fan_data) - return -ENOMEM; - fan_data->pdev = pdev; platform_set_drvdata(pdev, fan_data); mutex_init(&fan_data->lock); @@ -550,10 +615,23 @@ static int gpio_fan_probe(struct platform_device *pdev) return 0; } +static int gpio_fan_remove(struct platform_device *pdev) +{ + struct gpio_fan_data *fan_data = platform_get_drvdata(pdev); + + if (!IS_ERR(fan_data->cdev)) + thermal_cooling_device_unregister(fan_data->cdev); + + return 0; +} + static void gpio_fan_shutdown(struct platform_device *pdev) { struct gpio_fan_data *fan_data = dev_get_drvdata(&pdev->dev); + if (!IS_ERR(fan_data->cdev)) + thermal_cooling_device_unregister(fan_data->cdev); + if (fan_data->ctrl) set_fan_speed(fan_data, 0); } @@ -589,6 +667,7 @@ static SIMPLE_DEV_PM_OPS(gpio_fan_pm, gpio_fan_suspend, gpio_fan_resume); static struct platform_driver gpio_fan_driver = { .probe = gpio_fan_probe, + .remove = gpio_fan_remove, .shutdown = gpio_fan_shutdown, .driver = { .name = "gpio-fan", -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
