On 14/03/2023 08:27, Ulf Hansson wrote: > On Mon, 13 Mar 2023 at 22:42, Marc Gonzalez wrote: >> >> On 13/03/2023 21:04, Martin Blumenstingl wrote: >> >>> On Mon, Mar 13, 2023 at 6:09 PM Marc Gonzalez wrote: >>> [...] >>>> QUESTION: >>>> It's not clear to me why we sleep twice for host->ios.power_delay_ms? >>> >>> I'm not sure but I think host->ios.power_delay_ms is independent from >>> the post-power-on-delay-ms property of "mmc-pwrseq-simple". >> >> They are distinct indeed (the props have the same name & similar purpose though). > > Correct. > >> >> host->ios.power_delay_ms is set via: >> >> drivers/mmc/core/host.c: device_property_read_u32(dev, "post-power-on-delay-ms", > > This is a property that may be specified in the host's OF node. See > Documentation/devicetree/bindings/mmc/mmc-controller.yaml. > >> drivers/mmc/core/host.c- &host->ios.power_delay_ms); > > Note that the default value is set to 10 ms, in mmc_alloc_host(). So, > if you need a different value, that can be specified in DT. > >> >> >> pwrseq->post_power_on_delay_ms is set via: >> >> drivers/mmc/core/pwrseq_simple.c: device_property_read_u32(dev, "post-power-on-delay-ms", > > This is a property that may be specified in the pwrseq OF node. See > Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.yaml. > >> drivers/mmc/core/pwrseq_simple.c- &pwrseq->post_power_on_delay_ms); >> >> >> However, they are both used to delay mmc_power_up(), >> and the host delay is used to sleep twice, which I >> found confusing ;) > > It's certainly a bit hairy to follow, but I think you have understood > things correctly. > >> >> Regards >> > > Looks like you are getting closer to the solution, at least for the > first step to make sure the SDIO card is getting detected properly. > Nice! What I'm confused about is: Why would I specify the delay in the host rather than in the pwrseq? I'll have to study mmc_power_up() a bit more ;) Regards
