On Tue, Dec 01, 2015 at 11:57:34PM -0500, Sinan Kaya wrote: > On 11/30/2015 10:17 PM, Vinod Koul wrote: > > On Mon, Nov 30, 2015 at 09:42:01AM -0500, Sinan Kaya wrote: > > > >>>> +static int hidma_mgmt_probe(struct platform_device *pdev) > >>>> +{ > >>>> + struct hidma_mgmt_dev *mgmtdev; > >>>> + struct resource *res; > >>>> + void __iomem *virtaddr; > >>>> + int irq; > >>>> + int rc; > >>>> + u32 val; > >>>> + > >>>> + pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT); > >>>> + pm_runtime_use_autosuspend(&pdev->dev); > >>>> + pm_runtime_set_active(&pdev->dev); > >>>> + pm_runtime_enable(&pdev->dev); > >>> > >>> at this time pm core will treat device as fully enabled and pm methods can > >>> be invoked, but you are not ready yet right. Typically these are done at the > >>> end of the probe unless you have a reason... > >> > >> I need it here because the clocks are declared as ACPI power resources. > >> The kernel is turning off all power resources during initialization. In > >> order for this code to touch the hardware, I need to call enable so that > >> clocks are enabled once again. > > > > The question is are you ready in your driver routines to be invoked by pm > > core? > > > > I don't have any support for suspend and resume PM APIs. The only PM > interface I support is PM runtime. PM can turn on/off the clocks based > on the reference counts it maintains after get/set APIs. Since PM is > turning off the clocks during power up before my driver load, I do need > to grab this lock to re-enable it during HW initialization. Then, let PM > turn off the clocks again after the AUTOSUSPEND_TIMEOUT when I'm done. > > Is there any other interaction with the PM that I'm not aware of? No this is fine. The the runtime_resume will be onvoked and it will request resources are those set before you enable the device? -- ~Vinod -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html