Re: [PATCH 04/13] OMAP: Introduce API to return a device list associated with a voltage domain

[Kevin Hilman <khilman@deeprootsystems.com>]

"Gopinath, Thara" <thara@ti.com> writes:

>>>-----Original Message-----
>>>From: Kevin Hilman [mailto:khilman@deeprootsystems.com]
>>>Sent: Thursday, September 02, 2010 6:04 AM
>>>To: Gopinath, Thara
>>>Cc: linux-omap@vger.kernel.org; paul@pwsan.com; Sripathy, Vishwanath; Sawant, Anand; Cousson, Benoit
>>>Subject: Re: [PATCH 04/13] OMAP: Introduce API to return a device list associated with a voltage
>>>domain
>>>
>>>Thara Gopinath <thara@ti.com> writes:
>>>
>>>> This patch adds an API in the opp layer that
>>>> can be used by the voltage layer to get a list of all the
>>>> scalable devices belonging to a particular voltage domain.
>>>> This API is to be typically called only once by the voltage
>>>> layer per voltage domain instance and the device list should
>>>> be stored. This approach makes it easy during dvfs to scale
>>>> all the devices associated with a voltage domain and then
>>>> scale the voltage domain.
>>>>
>>>> Signed-off-by: Thara Gopinath <thara@ti.com>
>>>
>>>I don't think the OPP layer is the right place for this after all.
>>>
>>>How about something like this in the voltage layer:
>>>
>>>  omap_voltage_add_device(struct voltagedomain *voltdm, struct device *dev)
>>>
>>>During omap_device_build(), if the hwmod has a voltage domain, it
>>>calls this function to register it with the voltage layer.
>
> This mandates voltage layer to be initialized before the first omap_device_build
> has happened. I think that is going to be a very confusing sequencing. Also today
> voltage layer init happens later in the system.

If we split into an early and late init, that would help here too.

Kevin