input: keyboard: add syscore_ops support to gpio_key driver

Add syscore_ops support for gpio-keys driver to service
wakeable irq handler before the CPUs resume after
suspend state.

Signed-off-by: Shantanu Jain <shjain@codeaurora.org>
Change-Id: I7fe266661abfd469c68309a66aed0cb0fa2de33e

1 files changed, 74 insertions, 3 deletions

diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
index cf29f2756b84..c93dd193a496 100644
--- a/drivers/input/keyboard/gpio_keys.c
+++ b/drivers/input/keyboard/gpio_keys.c
@@ -3,6 +3,7 @@
  *
  * Copyright 2005 Phil Blundell
  * Copyright 2010, 2011 David Jander <david@protonic.nl>
+ * Copyright (c) 2015, 2017, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -32,6 +33,7 @@
 #include <linux/of_irq.h>
 #include <linux/spinlock.h>
 #include <linux/pinctrl/consumer.h>
+#include <linux/syscore_ops.h>
 
 struct gpio_button_data {
 	const struct gpio_keys_button *button;
@@ -57,6 +59,11 @@ struct gpio_keys_drvdata {
 	struct gpio_button_data data[0];
 };
 
+static struct device *global_dev;
+static struct syscore_ops gpio_keys_syscore_pm_ops;
+
+static void gpio_keys_syscore_resume(void);
+
 /*
  * SYSFS interface for enabling/disabling keys and switches:
  *
@@ -343,14 +350,14 @@ static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata)
 	const struct gpio_keys_button *button = bdata->button;
 	struct input_dev *input = bdata->input;
 	unsigned int type = button->type ?: EV_KEY;
-	int state = gpio_get_value_cansleep(button->gpio);
+	int state;
 
+	state = (__gpio_get_value(button->gpio) ? 1 : 0) ^ button->active_low;
 	if (state < 0) {
 		dev_err(input->dev.parent, "failed to get gpio state\n");
 		return;
 	}
 
-	state = (state ? 1 : 0) ^ button->active_low;
 	if (type == EV_ABS) {
 		if (state)
 			input_event(input, type, button->code, button->value);
@@ -664,6 +671,8 @@ gpio_keys_get_devtree_pdata(struct device *dev)
 	pdata->nbuttons = nbuttons;
 
 	pdata->rep = !!of_get_property(node, "autorepeat", NULL);
+	pdata->name = of_get_property(node, "input-name", NULL);
+	pdata->use_syscore = of_property_read_bool(node, "use-syscore");
 
 	i = 0;
 	for_each_child_of_node(node, pp) {
@@ -710,7 +719,7 @@ gpio_keys_get_devtree_pdata(struct device *dev)
 		button->can_disable = !!of_get_property(pp, "linux,can-disable", NULL);
 
 		if (of_property_read_u32(pp, "debounce-interval",
-					 &button->debounce_interval))
+					&button->debounce_interval))
 			button->debounce_interval = 5;
 	}
 
@@ -767,6 +776,7 @@ static int gpio_keys_probe(struct platform_device *pdev)
 		return -ENOMEM;
 	}
 
+	global_dev = dev;
 	ddata->pdata = pdata;
 	ddata->input = input;
 	mutex_init(&ddata->disable_lock);
@@ -835,6 +845,11 @@ static int gpio_keys_probe(struct platform_device *pdev)
 
 	device_init_wakeup(&pdev->dev, wakeup);
 
+	if (pdata->use_syscore)
+		gpio_keys_syscore_pm_ops.resume = gpio_keys_syscore_resume;
+
+	register_syscore_ops(&gpio_keys_syscore_pm_ops);
+
 	return 0;
 
 err_remove_group:
@@ -857,6 +872,7 @@ err_setup_key:
 static int gpio_keys_remove(struct platform_device *pdev)
 {
 	sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
+	unregister_syscore_ops(&gpio_keys_syscore_pm_ops);
 
 	device_init_wakeup(&pdev->dev, 0);
 
@@ -864,6 +880,41 @@ static int gpio_keys_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_PM_SLEEP
+static void gpio_keys_syscore_resume(void)
+{
+	struct gpio_keys_drvdata *ddata = dev_get_drvdata(global_dev);
+	struct input_dev *input = ddata->input;
+	struct gpio_button_data *bdata = NULL;
+	int error = 0;
+	int i;
+
+	if (ddata->key_pinctrl) {
+		error = gpio_keys_pinctrl_configure(ddata, true);
+		if (error) {
+			dev_err(global_dev, "failed to put the pin in resume state\n");
+			return;
+		}
+	}
+
+	if (device_may_wakeup(global_dev)) {
+		for (i = 0; i < ddata->pdata->nbuttons; i++) {
+			bdata = &ddata->data[i];
+			if (bdata->button->wakeup)
+				disable_irq_wake(bdata->irq);
+		}
+	} else {
+		mutex_lock(&input->mutex);
+		if (input->users)
+			error = gpio_keys_open(input);
+		mutex_unlock(&input->mutex);
+	}
+
+	if (error)
+		return;
+
+	gpio_keys_report_state(ddata);
+}
+
 static int gpio_keys_suspend(struct device *dev)
 {
 	struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev);
@@ -901,6 +952,11 @@ static int gpio_keys_resume(struct device *dev)
 	int error = 0;
 	int i;
 
+	if (ddata->pdata->use_syscore == true) {
+		dev_dbg(global_dev, "Using syscore resume, no need of this resume.\n");
+		return 0;
+	}
+
 	if (ddata->key_pinctrl) {
 		error = gpio_keys_pinctrl_configure(ddata, true);
 		if (error) {
@@ -928,6 +984,21 @@ static int gpio_keys_resume(struct device *dev)
 	gpio_keys_report_state(ddata);
 	return 0;
 }
+
+#else
+
+static void gpio_keys_syscore_resume(void){}
+
+static int gpio_keys_suspend(struct device *dev)
+{
+	return 0;
+}
+
+static int gpio_keys_resume(struct device *dev)
+{
+	return 0;
+}
+
 #endif
 
 static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume);