Input: serio - add fast reconnect option (5ea13206) · Commits · 戴 / test

Devices connected to serio bus are quite slow, and to improve apparent speed of resume process, serio core resumes (reconnects) its devices asynchronously, by posting port reconnect requests to a workqueue. Unfortunately this means that if there is a dependent device of a given serio port (for example SMBus part of touchpad connected via both PS/2 and SMBus), we do not have a good way of ensuring resume order. This change allows drivers to define "fast reconnect" handlers that would be called in-line during system resume. Drivers need to ensure that these handlers are truly "fast". Reviewed-by:

Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by:

Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/serio/serio.c

+17 −5

Original line number	Diff line number	Diff line
		@@ -953,12 +953,24 @@ static int serio_suspend(struct device *dev)
		static int serio_resume(struct device *dev)
		{
		struct serio *serio = to_serio_port(dev);
		int error = -ENOENT;

		mutex_lock(&serio->drv_mutex);
		if (serio->drv && serio->drv->fast_reconnect) {
		error = serio->drv->fast_reconnect(serio);
		if (error && error != -ENOENT)
		dev_warn(dev, "fast reconnect failed with error %d\n",
		error);
		}
		mutex_unlock(&serio->drv_mutex);

		if (error) {
		/*
		* Driver reconnect can take a while, so better let kseriod
		* deal with it.
		* Driver reconnect can take a while, so better let
		* kseriod deal with it.
		*/
		serio_queue_event(serio, NULL, SERIO_RECONNECT_PORT);
		}

		return 0;
		}

include/linux/serio.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -77,6 +77,7 @@ struct serio_driver {
		irqreturn_t (interrupt)(struct serio , unsigned char, unsigned int);
		int (connect)(struct serio , struct serio_driver *drv);
		int (reconnect)(struct serio );
		int (fast_reconnect)(struct serio );
		void (disconnect)(struct serio );
		void (cleanup)(struct serio );

Original line number	Diff line number	Diff line
		@@ -77,6 +77,7 @@ struct serio_driver {
		irqreturn_t (interrupt)(struct serio , unsigned char, unsigned int);
		int (connect)(struct serio , struct serio_driver *drv);
		int (reconnect)(struct serio );
		int (fast_reconnect)(struct serio );
		void (disconnect)(struct serio );
		void (cleanup)(struct serio );

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