On Thu, 2015-05-28 at 14:10 +0100, Lee Jones wrote:
> On Thu, 28 May 2015, Andy Shevchenko wrote:
> > On Wed, 2015-05-27 at 11:22 +0100, Lee Jones wrote:
> > > On Mon, 25 May 2015, Andy Shevchenko wrote:
[]
> > > > + intel_lpss_ltr_expose(lpss);
> > > > +
> > > > + ret = intel_lpss_debugfs_add(lpss);
> > > > + if (ret)
> > > > + dev_warn(lpss->dev, "Failed to create debugfs entries\n");
> > > > +
> > > > + if (intel_lpss_has_idma(lpss)) {
> > > > + /*
> > > > + * Ensure the DMA driver is loaded before the host
> > > > + * controller device appears, so that the host controller
> > > > + * driver can request its DMA channels as early as
> > > > + * possible.
> > > > + *
> > > > + * If the DMA module is not there that's OK as well.
> > > > + */
> > > > + intel_lpss_request_dma_module(LPSS_IDMA_DRIVER_NAME);
> > > > +
> > > > + ret = mfd_add_devices(dev, lpss->devid, lpss->devs, 2,
> > > > + info->mem, info->irq, NULL);
> > > > + } else {
> > > > + ret = mfd_add_devices(dev, lpss->devid, lpss->devs + 1, 1,
> > > > + info->mem, info->irq, NULL);
> > > > + }
> > >
> > > I'm still not happy with the mfd_cells being manipulated in this way,
> > > or with the duplication you have within them. Why don't you place the
> > > IDMA device it its own mfd_cell, then:
> > >
> > > > + if (intel_lpss_has_idma(lpss)) {
> > > > + intel_lpss_request_dma_module(LPSS_IDMA_DRIVER_NAME);
> > > > +
> > > > + ret = mfd_add_devices(dev, TBC, idma_dev, ARRAY_SIZE(idma_dev),
> > > > + info->mem, info->irq, NULL);
> > > > + /* Error check */
> > > > + }
> > > > +
> > > > + ret = mfd_add_devices(dev, TBC, proto_dev, ARRAY_SIZE(proto_dev),
> > > > + info->mem, info->irq, NULL);
> >
> > Would be nicer to export mfd_add_device() in that case?
>
> What do you mean by export? What's wrong with using this code
> segment?
I took a closer look into this, indeed, we can call mfd_add_devices() as
many time as we want to add a new child device.
Will refactor this piece of code.
> > > > +#ifdef CONFIG_PM_SLEEP
> > > > +#define INTEL_LPSS_SLEEP_PM_OPS \
> > > > + .prepare = intel_lpss_prepare, \
> > > > + .suspend = intel_lpss_suspend, \
> > > > + .resume = intel_lpss_resume, \
> > > > + .freeze = intel_lpss_suspend, \
> > > > + .thaw = intel_lpss_resume, \
> > > > + .poweroff = intel_lpss_suspend, \
> > > > + .restore = intel_lpss_resume,
> > > > +#endif
> > > > +
> > > > +#define INTEL_LPSS_RUNTIME_PM_OPS \
> > > > + .runtime_suspend = intel_lpss_suspend, \
> > > > + .runtime_resume = intel_lpss_resume,
> > > > +
> > > > +#else /* !CONFIG_PM */
> > > > +#define INTEL_LPSS_SLEEP_PM_OPS
> > > > +#define INTEL_LPSS_RUNTIME_PM_OPS
> > > > +#endif /* CONFIG_PM */
> > > > +
> > > > +#define INTEL_LPSS_PM_OPS(name) \
> > > > +const struct dev_pm_ops name = { \
> > > > + INTEL_LPSS_SLEEP_PM_OPS \
> > > > + INTEL_LPSS_RUNTIME_PM_OPS \
> >
> > > If you _really_ need .prepare, then it's likely that some other
> > > platform might too. It will be the same amount of code to just make
> > > this generic, so do that instead please.
> >
> > In 'linux/pm.h' ->prepare() is excluded since it's quite exotic to be
> > in device drivers. That is my understanding why it makes not much sense
> > to provide a generic definition for that.
> >
> > $ git grep -n '\.prepare[ \t]*=.*pm' drivers/ | wc -l
> > 33
> > $ git grep -n SET_SYSTEM_SLEEP_PM_OPS drivers/ | wc -l
> > 114
> > $ git grep -n UNIVERSAL_DEV_PM_OPS drivers/ | wc -l
> > 9
> > …and there are a lot of drivers (hundreds+) that do
> > not use mentioned macros, and has no ->prepare() callback defined.
> >
> > I can try to summon up Rafael to clarify this.
>
> Yes, let's do that, as I'd like a second opinion on this, thanks.
Rafael, it would be nice to have your input here.
--
Andy Shevchenko <andriy.shevchenko@xxxxxxxxx>
Intel Finland Oy
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