Re: [PATCH 1/8] dt-bindings: phy: Document ST STM32MP25 USB2-FEMTO PHY
Marek Vasut <[email protected]>
| Newsgroups | org.kernel.vger.linux-usb,org.infradead.lists.linux-arm-kernel,org.infradead.lists.linux-phy,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel |
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| Message-ID | <[email protected]> |
On 8/13/26 12:51 AM, Rob Herring wrote: > On Wed, Aug 12, 2026 at 08:30:33PM +0200, Marek Vasut wrote: >> On 8/12/26 1:22 PM, Krzysztof Kozlowski wrote: >>> On 12/08/2026 12:56, Marek Vasut wrote: >>>> On 8/12/26 12:15 PM, Krzysztof Kozlowski wrote: >>>>> On Wed, Aug 12, 2026 at 02:55:41AM +0200, Marek Vasut wrote: >>>>>> From: Pankaj Dev <[email protected]> >>>>>> >>>>>> Document USB2 PHY for STM32MP25 USB2 controllers, which includes the >>>>>> USB2.0 host-only controller and USB 2.0 part of the DWC3 controller. >>>>>> Two such PHYs in total are present in STM32MP25 SoC, they both are >>>>>> slightly different, therefore they use different compatible string >>>>> >>>>> What is slightly different? This should be either here, or better, in >>>>> "description" part. >>>> >>>> They are both Synopsys FEMTO-PHY , but they are each attached to a >>>> different controller (one to USB 2.0 host , the other to DWC3 DRD) , and >>>> their control bits in the system controller register are different for >>>> each variant. >>>> >>>> I extended the description in V2. >>> >>> Depending on the actual difference, this rather belongs to the phandle >>> to syscon, instead of separate compatible. >> >> Modeling that in the phandle to syscon won't scale, the PHY driver is simple >> thus far and does not control all the bits in that syscon, if we were to >> somehow extend the phandle to syscon to describe the various bit mappings >> and differences in it, it would look awful quickly. Hence the separate >> compatible strings, so the driver can match on them, derive match data from >> them and use the match data to figure out differences of each instance. > > There's no 'reg' so the syscon is the only control interface, right? Correct. > So this should be child node of the syscon (with a reg property). All right, will do in V2 (already done locally). Thanks !