Re: Query: Clock driver requests mailbox channel

[Leo Yan <leo.yan@linaro.org>]

On Tue, Jul 07, 2015 at 10:54:55AM +0530, Jassi Brar wrote:
> On Mon, Jul 6, 2015 at 5:03 PM, Leo Yan <leo.yan@linaro.org> wrote:
> > Hi all,
> >
> > i'm working with one clock driver, which will invoke mailbox API to
> > request the mailbox channel and send message.
> >
> > Usually clock driver will init with devicetree, below is the example:
> > CLK_OF_DECLARE(hi6220_clk_power, "hisilicon,hi6220-clock-power",
> > hi6220_clk_power_init);
> >
> > Clock init function it will pass the pointer of struct device_node
> > but not the pointer of struct device. So finally it's difficult to
> > invoke mailbox API *mbox_request_channel()*, due it need use the
> > struct device to search DT's property "mboxes".
> >
> > I want to find which is the best way to resolve this issue, so do you
> > suggest clock driver to manually register one device? Or can we add
> > one more API to request the mailbox channel directly with device_node?
> >
> IIUC, such clocks (that require platform resources) should be
> populated from the platform_device's probe()?

Thanks for response, Jassi. If we use general platform_device's probe()
function, then we can smoothly to get device poiner.

But if we use the method with CLK_OF_DECLARE, then i tried to get device
pointer with the function of_find_device_by_node(), it will return the
device pointer is NULL. But this is the common case in many clock drivers.

So i just wander if can provide another mailbox API for this case,
which will only need to pass device node pointer?

Thanks,
Leo Yan