hwmon: (axi-fan-control) Make sure the clock is enabled

The core will only work if it's clock is enabled. This patch is a
minor enhancement to make sure that's the case.
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20210811114853.159298-2-nuno.sa@analog.comSigned-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/axi-fan-control.c

@@ -351,6 +351,11 @@ static int axi_fan_control_init(struct axi_fan_control_data *ctl,
 	return ret;
 }
 
+static void axi_fan_control_clk_disable(void *clk)
+{
+	clk_disable_unprepare(clk);
+}
+
 static const struct hwmon_channel_info *axi_fan_control_info[] = {
 	HWMON_CHANNEL_INFO(pwm, HWMON_PWM_INPUT),
 	HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_LABEL),
@@ -406,6 +411,14 @@ static int axi_fan_control_probe(struct platform_device *pdev)
 		return PTR_ERR(clk);
 	}
 
+	ret = clk_prepare_enable(clk);
+	if (ret)
+		return ret;
+
+	ret = devm_add_action_or_reset(&pdev->dev, axi_fan_control_clk_disable, clk);
+	if (ret)
+		return ret;
+
 	ctl->clk_rate = clk_get_rate(clk);
 	if (!ctl->clk_rate)
 		return -EINVAL;