Messages in this thread | | | Date | Wed, 16 Nov 2022 12:14:46 -0600 | From | Bjorn Helgaas <> | Subject | Re: [PATCH V5] PCI: loongson: Skip scanning unavailable child devices |
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On Wed, Nov 16, 2022 at 05:57:46PM +0800, Liu Peibao wrote: > On 11/15/22 1:11 AM, Bjorn Helgaas wrote: > > On Mon, Nov 14, 2022 at 03:43:46PM +0800, Liu Peibao wrote:
> > I assume there's a single device in the hardware, and both the > > "platform device" and the PCI device" refer to that single device? > > > > And there's some reason you prefer to use the platform device > > interface to enumerate that device? > > No, they are not the same device. For example, GMAC1(on chip PCI device) and > GPIO(platform device, not PCI device) 14 use the same pin. The function for > this pin can be configured by one bit in general register, eg, 0 for GPIO 14, > 1 for GMAC1. Sometimes, GPIO 14 is preferred, so configure the pin with > function GPIO 14 and disable GMAC1.
Ah, I see, so there's some circuit that can be driven by either the platform (GPIO) device or the PCI (GMAC1) device.
> Overall, how about the following refactored commit log: > > "This patch adds a mechanism to disable on chip PCI devices by DT. Typically, > when there are pins shareable between the platform device and the on chip PCI > device, if the PCI device is not preferred, add `status = "disabled"` property > to this PCI device DT node. > > For example, on LS2K1000, GMAC1(on chip PCI device) and GPIO(platform device, > not PCI device) 14 share the same pin. If GMAC1 is not preferred, add > `status = "disabled"` property in GMAC1 DT node."
Add a mechanism ...
(Instead of "This patch adds ..."; no need to say "this patch" because it's obvious that the commit log applies to *this patch*)
Add spaces before "(", e.g., "GMAC1 (on-chip PCI device)".
Looks good!
Bjorn
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