Re: [PATCH v2] ACPI: D3 states cleanup

[Lin Ming <ming.m.lin@intel.com>]

On Fri, 2012-04-20 at 10:23 +0800, Aaron Lu wrote:
> Hi,
> 
> On Fri, Apr 20, 2012 at 09:19:09AM +0800, Lin Ming wrote:
> > There are two ACPI D3 states defined now:
> > ACPI_STATE_D3 and ACPI_STATE_D3_COLD.
> > 
> > But the uses of these states are not clear/correct in some code.
> > For example, some code refer ACPI_STATE_D3 as D3hot and others refer
> > it as D3cold.
> > 
> > This patch introduces ACPI_STATE_D3_HOT to refer to ACPI D3hot state.
> > And changes ACPI_STATE_D3 to refer to ACPI D3cold state only.
> > Also redefines ACPI_STATE_D3_COLD the same as ACPI_STATE_D3.
> > 
> 
> With this patch now, if a device has _PS3, then we will set its D3hot
> flag valid. This doesn't feel right to me, since per our discussion the
> other day, we should assume _PS3 will put the device into D3cold.
> 
> Or do you mean: if _PS3 is available, then both D3hot and D3cold is
> valid from the perspective of acpi, it is the individual driver's
> responsibility to decide which state is actually valid and will be used.

Right.

ACPI_STATE_D3(same as ACPI_STATE_D3_COLD now) is always valid.

Lin Ming

> 
> -Aaron
> 
> > Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
> > Signed-off-by: Lin Ming <ming.m.lin@intel.com>
> > ---
> >  drivers/acpi/power.c   |    2 +-
> >  drivers/acpi/scan.c    |    9 +--------
> >  drivers/pci/pci-acpi.c |    4 ++--
> >  include/acpi/actypes.h |    7 ++++---
> >  4 files changed, 8 insertions(+), 14 deletions(-)
> > 
> > diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
> > index 7049a7d..330bb4d 100644
> > --- a/drivers/acpi/power.c
> > +++ b/drivers/acpi/power.c
> > @@ -631,7 +631,7 @@ int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
> >  	 * We know a device's inferred power state when all the resources
> >  	 * required for a given D-state are 'on'.
> >  	 */
> > -	for (i = ACPI_STATE_D0; i < ACPI_STATE_D3; i++) {
> > +	for (i = ACPI_STATE_D0; i < ACPI_STATE_D3_HOT; i++) {
> >  		list = &device->power.states[i].resources;
> >  		if (list->count < 1)
> >  			continue;
> > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
> > index 767e2dc..fbf38ad 100644
> > --- a/drivers/acpi/scan.c
> > +++ b/drivers/acpi/scan.c
> > @@ -869,7 +869,7 @@ static int acpi_bus_get_power_flags(struct acpi_device *device)
> >  	/*
> >  	 * Enumerate supported power management states
> >  	 */
> > -	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
> > +	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
> >  		struct acpi_device_power_state *ps = &device->power.states[i];
> >  		char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
> >  
> > @@ -884,13 +884,6 @@ static int acpi_bus_get_power_flags(struct acpi_device *device)
> >  				acpi_bus_add_power_resource(ps->resources.handles[j]);
> >  		}
> >  
> > -		/* The exist of _PR3 indicates D3Cold support */
> > -		if (i == ACPI_STATE_D3) {
> > -			status = acpi_get_handle(device->handle, object_name, &handle);
> > -			if (ACPI_SUCCESS(status))
> > -				device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
> > -		}
> > -
> >  		/* Evaluate "_PSx" to see if we can do explicit sets */
> >  		object_name[2] = 'S';
> >  		status = acpi_get_handle(device->handle, object_name, &handle);
> > diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
> > index 0f150f2..1929c0c 100644
> > --- a/drivers/pci/pci-acpi.c
> > +++ b/drivers/pci/pci-acpi.c
> > @@ -200,7 +200,7 @@ static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
> >  		return PCI_D1;
> >  	case ACPI_STATE_D2:
> >  		return PCI_D2;
> > -	case ACPI_STATE_D3:
> > +	case ACPI_STATE_D3_HOT:
> >  		return PCI_D3hot;
> >  	case ACPI_STATE_D3_COLD:
> >  		return PCI_D3cold;
> > @@ -223,7 +223,7 @@ static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
> >  		[PCI_D0] = ACPI_STATE_D0,
> >  		[PCI_D1] = ACPI_STATE_D1,
> >  		[PCI_D2] = ACPI_STATE_D2,
> > -		[PCI_D3hot] = ACPI_STATE_D3,
> > +		[PCI_D3hot] = ACPI_STATE_D3_HOT,
> >  		[PCI_D3cold] = ACPI_STATE_D3
> >  	};
> >  	int error = -EINVAL;
> > diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h
> > index eba6604..e8bcc47 100644
> > --- a/include/acpi/actypes.h
> > +++ b/include/acpi/actypes.h
> > @@ -499,9 +499,10 @@ typedef u64 acpi_integer;
> >  #define ACPI_STATE_D0                   (u8) 0
> >  #define ACPI_STATE_D1                   (u8) 1
> >  #define ACPI_STATE_D2                   (u8) 2
> > -#define ACPI_STATE_D3                   (u8) 3
> > -#define ACPI_STATE_D3_COLD              (u8) 4
> > -#define ACPI_D_STATES_MAX               ACPI_STATE_D3_COLD
> > +#define ACPI_STATE_D3_HOT               (u8) 3
> > +#define ACPI_STATE_D3                   (u8) 4
> > +#define ACPI_STATE_D3_COLD              ACPI_STATE_D3
> > +#define ACPI_D_STATES_MAX               ACPI_STATE_D3
> >  #define ACPI_D_STATE_COUNT              5
> >  
> >  #define ACPI_STATE_C0                   (u8) 0
> > -- 
> > 1.7.2.5
> > 
> > 
> > 
> > 
>