HID: i2c-hid: Use PM subsystem to manage wake irq

The I2C hid driver is currently manually managing the wake
IRQ. This change removes the explicit enable_irq_wake/disable_irq_wake
and instead relies on the PM subsystem. This is done by calling
dev_pm_set_wake_irq.

i2c_device_probe already calls dev_pm_set_wake_irq when using device
tree, and i2c_device_remove also already calls dev_pm_clear_wake_irq.
There could be some device tree systems that have incorrectly declared
`wake` capabilities, so this change will set the wake irq if one is
missing. This matches the previous behavior.

I tested this on an ACPI system that has a HID touchscreen and verified
the IRQ was armed for wake on suspend.

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20220929093200.v6.1.Id4b4bdfe06e2caf2d5a3c9dd4a9b1080c38b539c@changeid
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
index 0667b6022c3b768747862934a8e3631f114907fc..81169b39677016bb23906909a1efc29d3640fe84 100644 (file)
--- a/drivers/hid/i2c-hid/i2c-hid-core.c
+++ b/drivers/hid/i2c-hid/i2c-hid-core.c
@@ -26,6 +26,7 @@
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/pm.h>
+#include <linux/pm_wakeirq.h>
 #include <linux/device.h>
 #include <linux/wait.h>
 #include <linux/err.h>
@@ -112,7 +113,6 @@ struct i2c_hid {
 
        wait_queue_head_t       wait;           /* For waiting the interrupt */
 
-       bool                    irq_wake_enabled;
        struct mutex            reset_lock;
 
        struct i2chid_ops       *ops;
@@ -1018,6 +1018,15 @@ int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
        if (ret < 0)
                goto err_powered;
 
+       /*
+        * The wake IRQ should be declared via device tree instead of assuming
+        * the IRQ can wake the system. This is here for legacy reasons and
+        * will be removed once the i2c-core supports querying ACPI for wake
+        * capabilities.
+        */
+       if (!client->dev.power.wakeirq)
+               dev_pm_set_wake_irq(&client->dev, client->irq);
+
        hid = hid_allocate_device();
        if (IS_ERR(hid)) {
                ret = PTR_ERR(hid);
@@ -1099,7 +1108,6 @@ static int i2c_hid_core_suspend(struct device *dev)
        struct i2c_hid *ihid = i2c_get_clientdata(client);
        struct hid_device *hid = ihid->hid;
        int ret;
-       int wake_status;
 
        ret = hid_driver_suspend(hid, PMSG_SUSPEND);
        if (ret < 0)
@@ -1110,16 +1118,8 @@ static int i2c_hid_core_suspend(struct device *dev)
 
        disable_irq(client->irq);
 
-       if (device_may_wakeup(&client->dev)) {
-               wake_status = enable_irq_wake(client->irq);
-               if (!wake_status)
-                       ihid->irq_wake_enabled = true;
-               else
-                       hid_warn(hid, "Failed to enable irq wake: %d\n",
-                               wake_status);
-       } else {
+       if (!device_may_wakeup(&client->dev))
                i2c_hid_core_power_down(ihid);
-       }
 
        return 0;
 }
@@ -1130,18 +1130,9 @@ static int i2c_hid_core_resume(struct device *dev)
        struct i2c_client *client = to_i2c_client(dev);
        struct i2c_hid *ihid = i2c_get_clientdata(client);
        struct hid_device *hid = ihid->hid;
-       int wake_status;
 
-       if (!device_may_wakeup(&client->dev)) {
+       if (!device_may_wakeup(&client->dev))
                i2c_hid_core_power_up(ihid);
-       } else if (ihid->irq_wake_enabled) {
-               wake_status = disable_irq_wake(client->irq);
-               if (!wake_status)
-                       ihid->irq_wake_enabled = false;
-               else
-                       hid_warn(hid, "Failed to disable irq wake: %d\n",
-                               wake_status);
-       }
 
        enable_irq(client->irq);