OpenCloudOS-Kernel/include/linux/firmware/imx
Daniel Baluta 23d89aa0c2 firmware: imx-dsp: Export functions to request/free channels
In order to save power, we only need to request a channel
when the communication with the DSP active.

For this we export the following functions:
	- imx_dsp_request_channel, gets a channel with a given index
	- imx_dsp_free_channel, frees a channel with a given index

Notice that we still request channels at probe to support devices
that do not have PM callbacks implemented.

More explanations about why requesting a channel has an effect
on power savings:
 - requesting an mailbox channel will call mailbox's startup
   function.
 - startup function calls pm_runtime_get_sync which increments device
   usage count and will keep the device active. Specifically, mailbox
   clock will be always ON when a mailbox channel is requested.

Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Reviewed-by: Paul Olaru <paul.olaru@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2020-11-16 16:33:48 +08:00
..
svc firmware: imx: add dummy functions 2020-10-28 16:59:40 +08:00
dsp.h firmware: imx-dsp: Export functions to request/free channels 2020-11-16 16:33:48 +08:00
ipc.h firmware: imx: add dummy functions 2020-10-28 16:59:40 +08:00
sci.h firmware: imx: add dummy functions 2020-10-28 16:59:40 +08:00