Hi,
On 2/25/22 19:10, Mario Limonciello wrote:
> As the default low power policy applies to more chipsets and drives, it's
> important to make sure that drives actually support the policy that a user
> selected in their kernel configuration.
>
> If the drive doesn't support slumber, don't let the default policy for the
> ATA port be `min_power` or `min_power_with_partial`.
>
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> ---
> drivers/ata/ahci.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
> index 17d757ad7111..af8999453084 100644
> --- a/drivers/ata/ahci.c
> +++ b/drivers/ata/ahci.c
> @@ -1584,8 +1584,16 @@ static int ahci_init_msi(struct pci_dev *pdev, unsigned int n_ports,
> static void ahci_update_initial_lpm_policy(struct ata_port *ap,
> struct ahci_host_priv *hpriv)
> {
> + struct pci_dev *pdev = to_pci_dev(ap->host->dev);
> int policy = CONFIG_SATA_LPM_POLICY;
>
> + if (policy >= ATA_LPM_MIN_POWER_WITH_PARTIAL &&
> + !(hpriv->cap & HOST_CAP_SSC)) {
> + dev_warn(&pdev->dev,
> + "This drive doesn't support slumber; ignoring default SATA policy\n");
> + return;
> + }
> +
Don't the capabilties get checked later when the policy gets applied ?
At least I think they do get checked later, but I have not looked
at this code for years ... ?
Regards,
Hans
> /* user modified policy via module param */
> if (mobile_lpm_policy != -1) {
> policy = mobile_lpm_policy;
