linux-kernel - Re: [PATCH v2] ACPI: D3 states cleanup

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Fri, 20 Apr 2012 10:23:13 +0800
From:	Aaron Lu <aaron.lu@....com>
To:	Lin Ming <ming.m.lin@...el.com>, "Rafael J. Wysocki" <rjw@...k.pl>
CC:	lenb <lenb@...nel.org>, linux-acpi <linux-acpi@...r.kernel.org>,
	<linux-kernel@...r.kernel.org>, Zhang Rui <rui.zhang@...el.com>,
	"Huang, Ying" <ying.huang@...el.com>
Subject: Re: [PATCH v2] ACPI: D3 states cleanup

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.

-Aaron

> Acked-by: Rafael J. Wysocki <rjw@...k.pl>
> Signed-off-by: Lin Ming <ming.m.lin@...el.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
> 
> 
> 
> 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/