On 24-10-07, Krzysztof Kozlowski wrote: > On 07/10/2024 14:58, POPESCU Catalin wrote: > >>>> > >>>> + vcc-supply: > >>>> + description: > >>>> + phandle of the regulator that provides the supply voltage. > >>>> + > >>>> + reset-gpios: > >>>> + description: > >>>> + Chip powerdown/reset signal (PDn). > >>>> + > >>> Hi Catalin, > >>> > >>> For NXP WIFI/BT chip, WIFI and BT share the one PDn pin, which means that both wifi and BT controller will be powered on and off at the same time. > >>> Taking the M.2 NXP WIFI/BT module as an example, pin56(W_DISABLE1) is connected to the WIFI/BT chip PDn pin, we has already controlled this pin in the corresponding PCIe/SDIO controller dts nodes. > >>> It is not clear to me what exactly pins for vcc-supply and reset-gpios you describing here. Can you help understand the corresponding pins on M.2 interface as an example? Thanks. > > > > Hi Sherry, > > > > Regulators and reset controls being refcounted, we can then implement > > powerup sequence in both bluetooth/wlan drivers and have the drivers > > operate independently. This way bluetooth driver would has no dependance > > on the wlan driver for : > > > > - its power supply > > > > - its reset pin (PDn) > > > > - its firmware (being downloaded as part of the combo firmware) > > > > For the wlan driver we use mmc power sequence to drive the chip reset > > pin and there's another patchset that adds support for reset control > > into the mmc pwrseq simple driver. > > > >> Please wrap your replies. > >> > >> It seems you need power sequencing just like Bartosz did for Qualcomm WCN. > > > > Hi Krzysztof, > > > > I'm not familiar with power sequencing, but looks like way more > > complicated than reset controls. So, why power sequencing is recommended > > here ? Is it b/c a supply is involved ? > > Based on earlier message: > > "For NXP WIFI/BT chip, WIFI and BT share the one PDn pin, which means > that both wifi and BT controller will be powered on and off at the same > time." > > but maybe that's not needed. No clue, I don't know the hardware. But be > carefully what you write in the bindings, because then it will be ABI. We noticed the new power-sequencing infrastructure which is part of 6.11 too but I don't think that this patch is wrong. The DT ABI won't break if we switch to the power-sequencing later on since the "reset-gpios" are not marked as required. So it is up to the driver to handle it either via a separate power-sequence driver or via "power-supply" and "reset-gpios" directly. Regards, Marco > Best regards, > Krzysztof > >
