Hi Peter, Em sáb., 12 de jun. de 2021 às 03:24, Peter Chen <peter.chen@xxxxxxxxxx> escreveu: > > On 21-06-11 10:56:07, Breno Lima wrote: > > i.MX8MM cannot detect certain CDP USB HUBs. usbmisc_imx.c driver is not > > following CDP timing requirements defined by USB BC 1.2 specification > > and section 3.2.4 Detection Timing CDP. > > > > During Primary Detection the i.MX device should turn on VDP_SRC and > > IDM_SINK for a minimum of 40ms (TVDPSRC_ON). After a time of TVDPSRC_ON, > > the PD is allowed to check the status of the D- line. Current > > implementation is waiting between 1ms and 2ms, and certain BC 1.2 > > complaint USB HUBs cannot be detected. Increase delay to 40ms allowing > > enough time for primary detection. > > > > During secondary detection the PD is required to disable VDP_SRC and > > What does the "PD" mean here? > PD stands for Portable Device, I can send another version and mention i.MX instead. Thanks for pointing this out. Best regards, Breno Lima
