Re: [PATCH 01/10] ata: libata-core: Introduce ata_dev_config_lpm()

[Hannes Reinecke <hare@suse.de>]

On 6/30/25 08:26, Damien Le Moal wrote:
> If the port of a device does not support Device Initiated Power
> Management (DIPM), that is, the port is flagged with ATA_FLAG_NO_DIPM,
> the DIPM feature of a device should be disabled when the device is first
> configured.
> 
> Introduce the function ata_dev_config_lpm() to disable DIPM on a
> device that supports this feature if the port of the device is flagged
> with ATA_FLAG_NO_DIPM. ata_dev_config_lpm() is called from
> ata_dev_configure(), ensuring that a device DIPM feature is disabled
> when it cannot be used.
> 
> Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
> ---
>   drivers/ata/libata-core.c | 22 ++++++++++++++++++++++
>   1 file changed, 22 insertions(+)
> 
> diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
> index 3918ea624e0b..0d85474f6640 100644
> --- a/drivers/ata/libata-core.c
> +++ b/drivers/ata/libata-core.c
> @@ -2790,6 +2790,27 @@ static void ata_dev_config_cpr(struct ata_device *dev)
>   	kfree(buf);
>   }
>   
> +/*
> + * Configure features related to link power management.
> + */
> +static void ata_dev_config_lpm(struct ata_device *dev)
> +{
> +	struct ata_port *ap = dev->link->ap;
> +	unsigned int err_mask;
> +
> +	/*
> +	 * If the device port does not support Device Initiated Power Management
> +	 * (DIPM), and the device supports this feature, disable it.
> +	 */
> +	if (ap->flags & ATA_FLAG_NO_DIPM && ata_id_has_dipm(dev->id)) {
> +		err_mask = ata_dev_set_feature(dev,
> +					SETFEATURES_SATA_DISABLE, SATA_DIPM);
> +		if (err_mask && err_mask != AC_ERR_DEV)
> +			ata_dev_err(dev, "Disable DIPM failed, Emask 0x%x\n",
> +				    err_mask);
> +	}
> +}
> +

Why is it called 'ata_dev_config_lpm()', when it actually disables DIPM?
Why not 'ata_dev_config_dipm()'?

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
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