On Tue, Apr 21, 2020 at 5:01 PM Ulf Hansson ulf.hansson@linaro.org wrote:
On Wed, 4 Mar 2020 at 13:20, Daniel Baluta daniel.baluta@oss.nxp.com wrote:
From: Daniel Baluta daniel.baluta@nxp.com
This patch introduces helpers support for multi PM domains.
API consists of:
- dev_multi_pm_attach - powers up all PM domains associated with a given
device. Because we can attach one PM domain per device, we create virtual devices (children of initial device) and associate PM domains one per virtual device.
- dev_multi_pm_detach - detaches all virtual devices from PM domains
attached with.
Signed-off-by: Daniel Baluta daniel.baluta@nxp.com
First, apologize for the delay.
In general I don't mind adding helpers that can be used to decrease open coding. However, in this case, I wonder how useful the helpers would really be.
More precisely, according to the information I have, a device may not always need all of its PM domains to be turned on together, but perhaps only a subset of them. Depending on the current use case that is running.
Of course, some cases follow your expectations, but as stated, some others do not.
Do you have an idea how many users that would be able to switch to these new APIs as of today?
IMX Sound Open Firmware driver will immediately be available to use this new API.
https://elixir.bootlin.com/linux/latest/source/sound/soc/sof/imx/imx8.c#L221
Aside, from that there are the ACM clock modules for i.MX8QXP / i.MX8QM. Also, looking at our internal tree there are XUVI, VPU, DPU drivers that need multi power domain support.
Anson, Aisheng do you have a number of users on your side for multi power domain?
thanks, daniel.