The PWM FAN device can now be used as a thermal cooling device. Necessary infrastructure has been added in this commit. Signed-off-by: Lukasz Majewski <l.majewski@xxxxxxxxxxx> --- drivers/hwmon/pwm-fan.c | 79 ++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 78 insertions(+), 1 deletion(-) diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c index 5854bb3..97b77e9 100644 --- a/drivers/hwmon/pwm-fan.c +++ b/drivers/hwmon/pwm-fan.c @@ -24,6 +24,7 @@ #include <linux/platform_device.h> #include <linux/pwm.h> #include <linux/sysfs.h> +#include <linux/thermal.h> #define MAX_PWM 255 @@ -68,6 +69,17 @@ exit_set_pwm_err: return ret; } +static void pwm_fan_update_state(struct pwm_fan_ctx *ctx, unsigned long pwm) +{ + int i; + + for (i = 0; i < ctx->pwm_fan_max_state; ++i) + if (pwm < ctx->pwm_fan_cooling_states[i + 1]) + break; + + ctx->pwm_fan_state = i; +} + static ssize_t set_pwm(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { @@ -82,6 +94,7 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *attr, if (ret) return ret; + pwm_fan_update_state(ctx, pwm); return count; } @@ -103,6 +116,59 @@ static struct attribute *pwm_fan_attrs[] = { ATTRIBUTE_GROUPS(pwm_fan); +/* thermal cooling device callbacks */ +static int pwm_fan_get_max_state(struct thermal_cooling_device *cdev, + unsigned long *state) +{ + struct pwm_fan_ctx *ctx = cdev->devdata; + + *state = ctx->pwm_fan_max_state; + + return 0; +} + +static int pwm_fan_get_cur_state(struct thermal_cooling_device *cdev, + unsigned long *state) +{ + struct pwm_fan_ctx *ctx = cdev->devdata; + + if (!ctx) + return -EINVAL; + + *state = ctx->pwm_fan_state; + + return 0; +} + +static int +pwm_fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state) +{ + struct pwm_fan_ctx *ctx = cdev->devdata; + int ret; + + if (!ctx || (state > ctx->pwm_fan_max_state)) + return -EINVAL; + + if (state == ctx->pwm_fan_state) + return 0; + + ret = __set_pwm(ctx, ctx->pwm_fan_cooling_states[state]); + if (ret) { + dev_err(&cdev->device, "Cannot set pwm!\n"); + return ret; + } + + ctx->pwm_fan_state = state; + + return ret; +} + +static const struct thermal_cooling_device_ops pwm_fan_cooling_ops = { + .get_max_state = pwm_fan_get_max_state, + .get_cur_state = pwm_fan_get_cur_state, + .set_cur_state = pwm_fan_set_cur_state, +}; + int pwm_fan_of_get_cooling_data(struct device *dev, struct pwm_fan_ctx *ctx) { struct device_node *np = dev->of_node; @@ -148,8 +214,9 @@ int pwm_fan_of_get_cooling_data(struct device *dev, struct pwm_fan_ctx *ctx) static int pwm_fan_probe(struct platform_device *pdev) { - struct device *hwmon; + struct thermal_cooling_device *cdev; struct pwm_fan_ctx *ctx; + struct device *hwmon; int duty_cycle; int ret; @@ -194,6 +261,16 @@ static int pwm_fan_probe(struct platform_device *pdev) pwm_disable(ctx->pwm); return PTR_ERR(hwmon); } + + cdev = thermal_of_cooling_device_register(pdev->dev.of_node, "pwm-fan", + ctx, &pwm_fan_cooling_ops); + if (IS_ERR(cdev)) { + dev_err(&pdev->dev, + "Failed to register pwm-fan as thermal cooling device"); + pwm_disable(ctx->pwm); + return PTR_ERR(cdev); + } + return 0; } -- 2.0.0.rc2 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html