Re: [PATCH 10/15] libata: add dev->sata_spd_limit and helpers

[Jeff Garzik <jgarzik@pobox.com>]

Tejun Heo wrote:
> dev->sata_spd_limit contrains SATA PHY speed of the device and is
> initialized to the configured value on probing.
> 
> Currently, This is only valid for dev[0] but still put into ata_device
> instead of ata_port.  This is because 1. it's device constraints
> (ie. when hotpluggin, it should be cleared with other device info)
> 2. for port multiplier, link actually belongs to each device.
> 
> Three helper functions - ata_down_sata_spd_limit(),
> ata_set_sata_spd_needed() and ata_set_sata_spd() - are implemented.
> They will be used by ata_bus_probe() rewrite and later by EH.
> 
> Signed-off-by: Tejun Heo <htejun@gmail.com>

NAK, I definitely don't want to closely associate phy and device 
parameters, because they are fundamentally two different things.

We program and address PHYs, so perhaps a sata_phy struct is needed.

Port multipliers also get interesting because we need to use ATA-ish 
commands to talk to the PM phys.  Perhaps a struct ata_port_mult inside 
ata_device is warranted, where one stores an array of sata_phy structs, 
and other PM-specific details.

	Jeff