Subject: [PATCH v4] pinctrl: mediatek: Implement wake handler and suspend resume

From: [email-masked] (Sudeep Holla)
Date: Mon, 14 Sep 2015 12:16:23 +0100

On 12/09/15 10:50, maoguang meng wrote:
> hi Sudeep:
> 
> I test flowlling your blow suggestions,but the system can not be woken.
> 
> beacuse,mtk_eint_suspend will mask it.As we know if eint wakeup system
> it must be unmasked before enter suspend flow.
> 
> e.x
> 
> static int __maybe_unused elan_suspend(struct device *dev)
> {
> 	struct i2c_client *client = to_i2c_client(dev);
> 	struct elan_tp_data *data = i2c_get_clientdata(client);
> 	int ret;
> 
> 	/*
> 	 * We are taking the mutex to make sure sysfs operations are
> 	 * complete before we attempt to bring the device into low[er]
> 	 * power mode.
> 	 */
> 	ret = mutex_lock_interruptible(&data->sysfs_mutex);
> 	if (ret)
> 		return ret;
> 
> 	disable_irq(client->irq);
> 
> 	if (device_may_wakeup(dev)) {
> 		ret = elan_sleep(data);
> 		/* Enable wake from IRQ */
> 		data->irq_wake = (enable_irq_wake(client->irq) == 0);

This is wrong assumption in the driver. enable_irq_wake doesn't
implicitly enable the IRQ. So the disable_irq should be moved to else.
And the resume patch also needs to be fixed accordingly, otherwise you
may get unbalanced irq. But this should not be the reason for fixing the
pinctrl suspend/resume.

Regards,
Sudeep

--->8

diff --git a/drivers/input/mouse/elan_i2c_core.c
b/drivers/input/mouse/elan_i2c_core.c
index fa945304b9a5..7de26b04f45c 100644
--- a/drivers/input/mouse/elan_i2c_core.c
+++ b/drivers/input/mouse/elan_i2c_core.c
@@ -1117,13 +1117,13 @@ static int __maybe_unused elan_suspend(struct
device *dev)
        if (ret)
                return ret;

-       disable_irq(client->irq);
-
        if (device_may_wakeup(dev)) {
                ret = elan_sleep(data);
                /* Enable wake from IRQ */
                data->irq_wake = (enable_irq_wake(client->irq) == 0);
        } else {
+               disable_irq(client->irq);
+
                ret = elan_disable_power(data);
        }