[PATCH] cap11xx: add runtime PM support

[Matt Ranostay <mranostay@gmail.com>]

Puts device into DEEP SLEEP when no LEDs are in in the on-state, and no
input_handlers are in use. Also uses *_autosuspend to prevent a LED
trigger from constantly suspending and resuming device.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
---
 drivers/input/keyboard/cap11xx.c | 75 ++++++++++++++++++++++++++++++----------
 1 file changed, 57 insertions(+), 18 deletions(-)

diff --git a/drivers/input/keyboard/cap11xx.c b/drivers/input/keyboard/cap11xx.c
index b983b5a..4dc7690 100644
--- a/drivers/input/keyboard/cap11xx.c
+++ b/drivers/input/keyboard/cap11xx.c
@@ -14,6 +14,7 @@
 #include <linux/input.h>
 #include <linux/leds.h>
 #include <linux/of_irq.h>
+#include <linux/pm_runtime.h>
 #include <linux/regmap.h>
 #include <linux/i2c.h>
 #include <linux/gpio/consumer.h>
@@ -84,9 +85,9 @@ struct cap11xx_led {
 struct cap11xx_priv {
 	struct regmap *regmap;
 	struct input_dev *idev;
+	struct i2c_client *i2c_client;
 
 	struct cap11xx_led *leds;
-	int num_leds;
 
 	/* config */
 	u32 keycodes[];
@@ -207,13 +208,6 @@ out:
 
 static int cap11xx_set_sleep(struct cap11xx_priv *priv, bool sleep)
 {
-#ifdef CONFIG_LEDS_CLASS
-	/*
-	 * DLSEEP mode will turn off all LEDS, prevent this
-	 */
-	if (priv->num_leds)
-		return 0;
-#endif
 	return regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL,
 				  CAP11XX_REG_MAIN_CONTROL_DLSEEP,
 				  sleep ? CAP11XX_REG_MAIN_CONTROL_DLSEEP : 0);
@@ -223,14 +217,16 @@ static int cap11xx_input_open(struct input_dev *idev)
 {
 	struct cap11xx_priv *priv = input_get_drvdata(idev);
 
-	return cap11xx_set_sleep(priv, false);
+	pm_runtime_get(&priv->i2c_client->dev);
+
+	return 0;
 }
 
 static void cap11xx_input_close(struct input_dev *idev)
 {
 	struct cap11xx_priv *priv = input_get_drvdata(idev);
 
-	cap11xx_set_sleep(priv, true);
+	pm_runtime_put_autosuspend(&priv->i2c_client->dev);
 }
 
 #ifdef CONFIG_LEDS_CLASS
@@ -252,10 +248,16 @@ static void cap11xx_led_set(struct led_classdev *cdev,
 			   enum led_brightness value)
 {
 	struct cap11xx_led *led = container_of(cdev, struct cap11xx_led, cdev);
+	struct cap11xx_priv *priv = led->priv;
 
 	if (led->new_brightness == value)
 		return;
 
+	if (value)
+		pm_runtime_get(&priv->i2c_client->dev);
+	else
+		pm_runtime_put_autosuspend(&priv->i2c_client->dev);
+
 	led->new_brightness = value;
 	schedule_work(&led->work);
 }
@@ -312,7 +314,6 @@ static int cap11xx_init_leds(struct device *dev,
 		error = devm_led_classdev_register(dev, &led->cdev);
 		if (error < 0)
 			return -EINVAL;
-		priv->num_leds++;
 		led++;
 	};
 
@@ -446,17 +447,23 @@ static int cap11xx_i2c_probe(struct i2c_client *i2c_client,
 	priv->idev->open = cap11xx_input_open;
 	priv->idev->close = cap11xx_input_close;
 
-	error = cap11xx_init_leds(dev, priv, cap->num_leds);
+	error = cap11xx_set_sleep(priv, true);
 	if (error)
 		return error;
 
-	input_set_drvdata(priv->idev, priv);
+	error = pm_runtime_set_active(dev);
+	if (error)
+		return error;
 
-	/*
-	 * Put the device in deep sleep mode for now.
-	 * ->open() will bring it back once the it is actually needed.
-	 */
-	cap11xx_set_sleep(priv, true);
+	pm_runtime_enable(dev);
+	pm_runtime_set_autosuspend_delay(dev, 1000);
+	pm_runtime_use_autosuspend(dev);
+
+	error = cap11xx_init_leds(dev, priv, cap->num_leds);
+	if (error)
+		return error;
+	priv->i2c_client = i2c_client;
+	input_set_drvdata(priv->idev, priv);
 
 	error = input_register_device(priv->idev);
 	if (error)
@@ -476,6 +483,17 @@ static int cap11xx_i2c_probe(struct i2c_client *i2c_client,
 	return 0;
 }
 
+static int cap11xx_i2c_remove(struct i2c_client *i2c_client)
+{
+	struct cap11xx_priv *priv = i2c_get_clientdata(i2c_client);
+
+	pm_runtime_disable(&i2c_client->dev);
+	pm_runtime_set_suspended(&i2c_client->dev);
+	cap11xx_set_sleep(priv, true);
+
+	return 0;
+}
+
 static const struct of_device_id cap11xx_dt_ids[] = {
 	{ .compatible = "microchip,cap1106", },
 	{ .compatible = "microchip,cap1126", },
@@ -492,14 +510,35 @@ static const struct i2c_device_id cap11xx_i2c_ids[] = {
 };
 MODULE_DEVICE_TABLE(i2c, cap11xx_i2c_ids);
 
+static int cap11xx_runtime_suspend(struct device *dev)
+{
+	struct cap11xx_priv *priv = i2c_get_clientdata(to_i2c_client(dev));
+
+	return cap11xx_set_sleep(priv, true);
+}
+
+static int cap11xx_runtime_resume(struct device *dev)
+{
+	struct cap11xx_priv *priv = i2c_get_clientdata(to_i2c_client(dev));
+
+	return cap11xx_set_sleep(priv, false);
+}
+
+static const struct dev_pm_ops cap11xx_pm_ops = {
+	SET_RUNTIME_PM_OPS(cap11xx_runtime_suspend,
+			   cap11xx_runtime_resume, NULL)
+};
+
 static struct i2c_driver cap11xx_i2c_driver = {
 	.driver = {
 		.name	= "cap11xx",
 		.owner	= THIS_MODULE,
 		.of_match_table = cap11xx_dt_ids,
+		.pm	= &cap11xx_pm_ops,
 	},
 	.id_table	= cap11xx_i2c_ids,
 	.probe		= cap11xx_i2c_probe,
+	.remove		= cap11xx_i2c_remove,
 };
 
 module_i2c_driver(cap11xx_i2c_driver);
-- 
1.9.1