[PATCH 2/8] HID: i2c-hid: Use PM subsystem to manage wake irq

Raul E Rangel
2022-08-30T23:16:30Z

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, so it's only required when using ACPI. The net result is that this
change should be a no-op. i2c_device_remove also already calls
dev_pm_clear_wake_irq, so we don't need to do that in this driver.

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>
---

drivers/hid/i2c-hid/i2c-hid-core.c | 33 +++++++++++-------------------
1 file changed, 12 insertions(+), 21 deletions(-)

diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
index baa169fadd6632..0b7a1a8b3e9a33 100644
--- 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>
@@ -116,7 +117,6 @@ struct i2c_hid {

wait_queue_head_t wait; /* For waiting the interrupt */

- bool irq_wake_enabled;
struct mutex reset_lock;

struct i2chid_ops *ops;
@@ -1036,6 +1036,15 @@ int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
if (ret < 0)
goto err_powered;

+ /*
+ * Systems using device tree should set up wakeup via DTS,
+ * the rest will configure device as wakeup source by default.
+ */
+ if (!client->dev.of_node) {
+ device_init_wakeup(&client->dev, true);
+ dev_pm_set_wake_irq(&client->dev, client->irq);
+ }
+
hid = hid_allocate_device();
if (IS_ERR(hid)) {
ret = PTR_ERR(hid);
@@ -1119,7 +1128,6 @@ 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)
@@ -1130,16 +1138,8 @@ 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;
}
@@ -1150,18 +1150,9 @@ 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);

--
2.37.2.672.g94769d06f0-goog