Hi!
> From: Rafael J. Wysocki <rjw@xxxxxxx>
>
> The new suspend and hibernation callbacks introduced with
> 'struct pm_ops' and 'struct pm_ext_ops' do not take a
> pm_message_t argument, so the drivers using them will not be able
> to use pci_choose_state() in its present form. For this reason,
> introduce the new function pci_preferred_state() playing the role
> of pci_choose_state(), but taking only a pointer to the device
> object.
>
> Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx>
> ---
> drivers/pci/pci.c | 33 ++++++++++++++++++++++++++++++++-
> include/linux/pci.h | 1 +
> include/linux/pm.h | 10 ++++++++++
> 3 files changed, 43 insertions(+), 1 deletion(-)
>
> Index: linux-2.6/drivers/pci/pci.c
> ===================================================================
> --- linux-2.6.orig/drivers/pci/pci.c
> +++ linux-2.6/drivers/pci/pci.c
> @@ -509,7 +509,38 @@ pci_set_power_state(struct pci_dev *dev,
> }
>
> pci_power_t (*platform_pci_choose_state)(struct pci_dev *dev);
> -
> +
> +/**
> + * pci_preferred_state - Choose the preferred power state of a PCI device
> + * @dev: PCI device to be put into the low power state
> + * @sp: Information aboutabout what the driver would prefer to do with
> + * the device if there were no platform-implemeted policy.
> + *
> + * Returns PCI power state suitable for given device and given suspend policy.
> + * The policy, however, is only used if platform_pci_choose_state() fails or is
> + * not present. Otherwise, it is assumed that platform_pci_choose_state()
> + * implements the right policy.
> + */
> +
> +pci_power_t pci_preferred_state(struct pci_dev *dev, enum suspend_policy sp)
> +{
> + pci_power_t ret;
> +
> + if (!pci_find_capability(dev, PCI_CAP_ID_PM))
> + return PCI_D0;
> +
> + ret = (sp == SP_TURN_OFF) ? PCI_D3hot : PCI_D0;
> + if (platform_pci_choose_state) {
> + pci_power_t platform_ret = platform_pci_choose_state(dev);
> +
> + if (platform_ret != PCI_POWER_ERROR)
> + ret = platform_ret;
> + }
> + return ret;
> +}
> +
> +EXPORT_SYMBOL(pci_preferred_state);
I don't get it. How is driver supposed to use this? How does the
driver decide between SP_TURN_OFF and SP_TURN_ON?
...and it seems to be clearer to just inline this in the driver... or
pass PCI_D3hot/PCI_D0 to it, instead of inventing yet another
define...
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
_______________________________________________
linux-pm mailing list
linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linux-foundation.org/mailman/listinfo/linux-pm
