hwmon: (pwm-fan) Add optional regulator support

This adds optional regulator support to the pwm-fan driver. This is
necessary for pwm fans which are powered by a switchable supply.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index 2c944825026fb9f6be4202c35501f8a84fed828b..167221c7628a529626d8961e42f3cff373f8f72f 100644 (file)
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -23,6 +23,7 @@
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pwm.h>
+#include <linux/regulator/consumer.h>
 #include <linux/sysfs.h>
 #include <linux/thermal.h>
 
@@ -31,6 +32,7 @@
 struct pwm_fan_ctx {
        struct mutex lock;
        struct pwm_device *pwm;
+       struct regulator *reg_en;
        unsigned int pwm_value;
        unsigned int pwm_fan_state;
        unsigned int pwm_fan_max_state;
@@ -231,6 +233,21 @@ static int pwm_fan_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, ctx);
 
+       ctx->reg_en = devm_regulator_get_optional(&pdev->dev, "fan");
+       if (IS_ERR(ctx->reg_en)) {
+               if (PTR_ERR(ctx->reg_en) != -ENODEV)
+                       return PTR_ERR(ctx->reg_en);
+
+               ctx->reg_en = NULL;
+       } else {
+               ret = regulator_enable(ctx->reg_en);
+               if (ret) {
+                       dev_err(&pdev->dev,
+                               "Failed to enable fan supply: %d\n", ret);
+                       return ret;
+               }
+       }
+
        ctx->pwm_value = MAX_PWM;
 
        /* Set duty cycle to maximum allowed and enable PWM output */
@@ -241,7 +258,7 @@ static int pwm_fan_probe(struct platform_device *pdev)
        ret = pwm_apply_state(ctx->pwm, &state);
        if (ret) {
                dev_err(&pdev->dev, "Failed to configure PWM\n");
-               return ret;
+               goto err_reg_disable;
        }
 
        hwmon = devm_hwmon_device_register_with_groups(&pdev->dev, "pwmfan",
@@ -277,6 +294,10 @@ static int pwm_fan_probe(struct platform_device *pdev)
        state.enabled = false;
        pwm_apply_state(ctx->pwm, &state);
 
+err_reg_disable:
+       if (ctx->reg_en)
+               regulator_disable(ctx->reg_en);
+
        return ret;
 }
 
@@ -287,6 +308,10 @@ static int pwm_fan_remove(struct platform_device *pdev)
        thermal_cooling_device_unregister(ctx->cdev);
        if (ctx->pwm_value)
                pwm_disable(ctx->pwm);
+
+       if (ctx->reg_en)
+               regulator_disable(ctx->reg_en);
+
        return 0;
 }
 
@@ -307,6 +332,14 @@ static int pwm_fan_suspend(struct device *dev)
                pwm_disable(ctx->pwm);
        }
 
+       if (ctx->reg_en) {
+               ret = regulator_disable(ctx->reg_en);
+               if (ret) {
+                       dev_err(dev, "Failed to disable fan supply: %d\n", ret);
+                       return ret;
+               }
+       }
+
        return 0;
 }
 
@@ -317,6 +350,14 @@ static int pwm_fan_resume(struct device *dev)
        unsigned long duty;
        int ret;
 
+       if (ctx->reg_en) {
+               ret = regulator_enable(ctx->reg_en);
+               if (ret) {
+                       dev_err(dev, "Failed to enable fan supply: %d\n", ret);
+                       return ret;
+               }
+       }
+
        if (ctx->pwm_value == 0)
                return 0;