[Intel-gfx] [PATCH] ACPI button: provide lid status functions

[Jesse Barnes]

On Fri, 11 Sep 2009 09:02:02 +0800
ykzhao <yakui.zhao at intel.com> wrote:

> On Fri, 2009-09-11 at 06:28 +0800, Jesse Barnes wrote:
> cc: linux-acpi
> > Some drivers need to know when a lid event occurs and get the
> > current status.  This can be useful for when a platform firmware
> > clobbers some hardware state at lid time, and a driver needs to
> > restore things when the lid is opened again.
> > 
> > Acked-by: Matthew Garrett <mjg59 at srcf.ucam.org>
> > Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
> > ---
> >  drivers/acpi/button.c |   45
> > +++++++++++++++++++++++++++++++++++++++++++-- include/acpi/button.h
> > |   10 ++++++++++ 2 files changed, 53 insertions(+), 2 deletions(-)
> >  create mode 100644 include/acpi/button.h
> > 
> > diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
> > index 9195deb..ebb593e 100644
> > --- a/drivers/acpi/button.c
> > +++ b/drivers/acpi/button.c
> > @@ -113,6 +113,9 @@ static const struct file_operations
> > acpi_button_state_fops = { .release = single_release,
> >  };
> >  
> > +static BLOCKING_NOTIFIER_HEAD(acpi_lid_notifier);
> > +static struct acpi_device *lid_device;
> > +
> >  /*
> > --------------------------------------------------------------------------
> > FS Interface (/proc)
> > --------------------------------------------------------------------------
> > */ @@ -229,11 +232,38 @@ static int acpi_button_remove_fs(struct
> > acpi_device *device) /*
> > --------------------------------------------------------------------------
> > Driver Interface
> > --------------------------------------------------------------------------
> > */ +int acpi_lid_notifier_register(struct notifier_block *nb) +{
> > +	return
> > blocking_notifier_chain_register(&acpi_lid_notifier, nb); +}
> > +EXPORT_SYMBOL(acpi_lid_notifier_register);
> > +
> > +int acpi_lid_notifier_unregister(struct notifier_block *nb)
> > +{
> > +	return
> > blocking_notifier_chain_unregister(&acpi_lid_notifier, nb); +}
> > +EXPORT_SYMBOL(acpi_lid_notifier_unregister);
> > +
> > +int acpi_lid_open(void)
> > +{
> > +	acpi_status status;
> > +	unsigned long long state;
> > +
> > +	status = acpi_evaluate_integer(lid_device->handle, "_LID",
> > NULL,
> > +				       &state);
> > +	if (ACPI_FAILURE(status))
> > +		return -ENODEV;
> > +
> > +	return !!state;
> > +}
> > +EXPORT_SYMBOL(acpi_lid_open);
> > +
> >  static int acpi_lid_send_state(struct acpi_device *device)
> >  {
> >  	struct acpi_button *button = acpi_driver_data(device);
> >  	unsigned long long state;
> >  	acpi_status status;
> > +	int ret;
> >  
> >  	status = acpi_evaluate_integer(device->handle, "_LID",
> > NULL, &state); if (ACPI_FAILURE(status))
> > @@ -242,7 +272,12 @@ static int acpi_lid_send_state(struct
> > acpi_device *device) /* input layer checks if event is redundant */
> >  	input_report_switch(button->input, SW_LID, !state);
> >  	input_sync(button->input);
> > -	return 0;
> > +
> > +	ret = blocking_notifier_call_chain(&acpi_lid_notifier,
> > state, device);
> > +	if (ret == NOTIFY_DONE)
> > +		ret =
> > blocking_notifier_call_chain(&acpi_lid_notifier, state,
> > +						   device);
> > +	return ret;
> >  }
> >  
> >  static void acpi_button_notify(struct acpi_device *device, u32
> > event) @@ -364,8 +399,14 @@ static int acpi_button_add(struct
> > acpi_device *device) error = input_register_device(input);
> >  	if (error)
> >  		goto err_remove_fs;
> > -	if (button->type == ACPI_BUTTON_TYPE_LID)
> > +	if (button->type == ACPI_BUTTON_TYPE_LID) {
> >  		acpi_lid_send_state(device);
> > +		/*
> > +		 * This assumes there's only one lid device, or if
> > there are
> > +		 * more we only care about the last one...
> > +		 */
> > +		lid_device = device;
> > +	}
> >  
> >  	if (device->wakeup.flags.valid) {
> >  		/* Button's GPE is run-wake GPE */
> > diff --git a/include/acpi/button.h b/include/acpi/button.h
> > new file mode 100644
> > index 0000000..bb643a7
> > --- /dev/null
> > +++ b/include/acpi/button.h
> > @@ -0,0 +1,10 @@
> > +#ifndef ACPI_BUTTON_H
> > +#define ACPI_BUTTON_H
> It will be better that the function prototype is defined in the
> following:
> 
> #if (defined(CONFIG_ACPI_BUTTON) ||
> defined(CONFIG_ACPI_BUTTON_MODULE)) extern int
> acpi_lid_notifier_register(struct notifier_block *nb); extern int
> acpi_lid_notifier_unregister(struct notifier_block *nb); extern int
> acpi_lid_open(void); #else
> static inline int acpi_lid_notifier_register( ...)  { return 0;}
> static inline int acpi_lid_notifier_unregister(struct notifier_block
> *nb) { return 0; }
> static inline int acpi_lid_open(void) { return 1; }
> #endif

Oh right, I missed that part.  I'll send a followup patch on top with
this fix (unless you beat me to it).

Thanks,
-- 
Jesse Barnes, Intel Open Source Technology Center