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authorNishanth Menon <nm@ti.com>2015-01-08 21:05:03 +0300
committerGuenter Roeck <linux@roeck-us.net>2015-03-09 19:59:36 +0300
commitb5cf88e46badea6d600d8515edea23814e03444d (patch)
treee34c800910768dbb574336ba3a9a914d793454fe /drivers/hwmon/gpio-fan.c
parentb6bddec01932b94a20b6a7bbb7ed9d98e82ec162 (diff)
downloadlinux-b5cf88e46badea6d600d8515edea23814e03444d.tar.xz
(gpio-fan): Add thermal control hooks
Allow gpio-fan to be used as thermal cooling device for platforms that use GPIO maps to control fans. As part of this change, we make the shutdown and remove logic the same as well. Signed-off-by: Nishanth Menon <nm@ti.com> Acked-by: Eduardo Valentin <edubezval@gmail.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon/gpio-fan.c')
-rw-r--r--drivers/hwmon/gpio-fan.c83
1 files changed, 76 insertions, 7 deletions
diff --git a/drivers/hwmon/gpio-fan.c b/drivers/hwmon/gpio-fan.c
index c241f5b0b7cf..632b8e3ff5bf 100644
--- a/drivers/hwmon/gpio-fan.c
+++ b/drivers/hwmon/gpio-fan.c
@@ -34,10 +34,13 @@
#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;
@@ -387,6 +390,53 @@ 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_cool_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
@@ -497,6 +547,11 @@ 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,
@@ -508,17 +563,20 @@ static int gpio_fan_probe(struct platform_device *pdev)
err = gpio_fan_get_of_pdata(&pdev->dev, pdata);
if (err)
return err;
+ /* Optional cooling device register for Device tree platforms */
+ fan_data->cdev =
+ thermal_of_cooling_device_register(pdev->dev.of_node,
+ "gpio-fan", fan_data,
+ &gpio_fan_cool_ops);
}
#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_cool_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);
@@ -552,12 +610,22 @@ static int gpio_fan_probe(struct platform_device *pdev)
return 0;
}
-static void gpio_fan_shutdown(struct platform_device *pdev)
+static int gpio_fan_remove(struct platform_device *pdev)
{
- struct gpio_fan_data *fan_data = dev_get_drvdata(&pdev->dev);
+ struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);
+
+ if (!IS_ERR(fan_data->cdev))
+ thermal_cooling_device_unregister(fan_data->cdev);
if (fan_data->ctrl)
set_fan_speed(fan_data, 0);
+
+ return 0;
+}
+
+static void gpio_fan_shutdown(struct platform_device *pdev)
+{
+ gpio_fan_remove(pdev);
}
#ifdef CONFIG_PM_SLEEP
@@ -591,6 +659,7 @@ 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",