Re: [PATCH 1/4] HID: core: Add hid_hw_may_wakeup() function
From: Benjamin Tissoires <hidden>
Date: 2021-06-24 12:16:56
Hi Hans, On 5/29/21 5:14 PM, Hans de Goede wrote:
Add a hid_hw_may_wakeup() function, which is the equivalent of hid_hw_may_wakeup() for hid devices.
nitpick here, but I think the second `hid_hw_may_wakeup()` is probably wrong.
In most cases this just returns device_may_wakeup(hdev->dev.parent), but for some ll-drivers this is not correct. E.g. usb_hid_driver instantiated hid devices have their parent set to the usb-interface to which the usb_hid_driver is bound, but the power/wakeup* sysfs attributes are part of the usb-device, which is the usb-interface's parent.
I never spent enough time in suspend/resume. But isn't the big consumer of wakeup sources be USB? Is there a point having a generic return path when returning false earlier will keep the same code path for all other transport layers (I2C and bluetooth)? Other than those two questions, I like the series and the approach to not break the existing: For the series: Reviewed-by: Benjamin Tissoires <redacted> Cheers, Benjamin
quoted hunk ↗ jump to hunk
For these special cases a new may_wakeup callback is added to hid_ll_driver, so that ll-drivers can override the default behavior. Signed-off-by: Hans de Goede <redacted> --- include/linux/hid.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)diff --git a/include/linux/hid.h b/include/linux/hid.h index 271021e20a3f..4d2b2212f079 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h@@ -800,6 +800,7 @@ struct hid_driver { * @raw_request: send raw report request to device (e.g. feature report) * @output_report: send output report to device * @idle: send idle request to device + * @may_wakeup: return if device may act as a wakeup source during system-suspend */ struct hid_ll_driver { int (*start)(struct hid_device *hdev);@@ -824,6 +825,7 @@ struct hid_ll_driver { int (*output_report) (struct hid_device *hdev, __u8 *buf, size_t len); int (*idle)(struct hid_device *hdev, int report, int idle, int reqtype); + bool (*may_wakeup)(struct hid_device *hdev); }; extern struct hid_ll_driver i2c_hid_ll_driver;@@ -1149,6 +1151,22 @@ static inline int hid_hw_idle(struct hid_device *hdev, int report, int idle, return 0; } +/** + * hid_may_wakeup - return if the hid device may act as a wakeup source during system-suspend + * + * @hdev: hid device + */ +static inline bool hid_hw_may_wakeup(struct hid_device *hdev) +{ + if (hdev->ll_driver->may_wakeup) + return hdev->ll_driver->may_wakeup(hdev); + + if (hdev->dev.parent) + return device_may_wakeup(hdev->dev.parent); + + return false; +} + /** * hid_hw_wait - wait for buffered io to complete *