From 995caae57d3af96faab2342f7f04e528b274e3cb Mon Sep 17 00:00:00 2001
From: SwtcR <swtcr0@gmail.com>
Date: Sun, 11 Feb 2018 06:15:52 +0900
Subject: [PATCH] pwm-fan: implement enable GPIO

---
 drivers/hwmon/Kconfig   |  2 +-
 drivers/hwmon/pwm-fan.c | 13 +++++++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index ef23553ff5cb..340cf085fa99 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1278,7 +1278,7 @@ source drivers/hwmon/pmbus/Kconfig
 
 config SENSORS_PWM_FAN
 	tristate "PWM fan"
-	depends on (PWM && OF) || COMPILE_TEST
+	depends on (PWM && OF && GPIOLIB && OF_GPIO) || COMPILE_TEST
 	depends on THERMAL || THERMAL=n
 	help
 	  If you say yes here you get support for fans connected to PWM lines.
diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index 70cc0d134f3c..c0cf501700b2 100644
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -18,6 +18,7 @@
 
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
+#include <linux/gpio/consumer.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of.h>
@@ -31,6 +32,7 @@
 struct pwm_fan_ctx {
 	struct mutex lock;
 	struct pwm_device *pwm;
+	struct gpio_desc *enable_gpio;
 	unsigned int pwm_value;
 	unsigned int pwm_fan_state;
 	unsigned int pwm_fan_max_state;
@@ -56,6 +58,10 @@ static int  __set_pwm(struct pwm_fan_ctx *ctx, unsigned long pwm)
 	ret = pwm_apply_state(ctx->pwm, &state);
 	if (!ret)
 		ctx->pwm_value = pwm;
+
+	if (ctx->enable_gpio)
+		gpiod_set_value(ctx->enable_gpio, !!pwm);
+
 exit_set_pwm_err:
 	mutex_unlock(&ctx->lock);
 	return ret;
@@ -240,6 +246,13 @@ static int pwm_fan_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	ctx->enable_gpio = devm_gpiod_get(&pdev->dev, "enable", GPIOD_OUT_HIGH);
+	if (IS_ERR(ctx->enable_gpio)) {
+		ctx->enable_gpio = NULL;
+	} else {
+		gpiod_set_value(ctx->enable_gpio, 1);
+	}
+
 	hwmon = devm_hwmon_device_register_with_groups(&pdev->dev, "pwmfan",
 						       ctx, pwm_fan_groups);
 	if (IS_ERR(hwmon)) {