Hi, Bin Liu <b-liu@xxxxxx> writes: > On 10/14/2015 10:56 AM, Felipe Balbi wrote: >> >> Hi, >> >> Bin Liu <b-liu@xxxxxx> writes: >>> Hi, >>> >>> On 10/13/2015 01:22 PM, Felipe Balbi wrote: >>>> Yegor Yefremov <yegorslists@xxxxxxxxxxxxxx> writes: >>>>> On Mon, Oct 12, 2015 at 11:34 AM, Yegor Yefremov >>>>> <yegorslists@xxxxxxxxxxxxxx> wrote: >>>>>> We have a problem, when using more than 12 FTDI ports. Kernels tried: >>>>>> 3.18.1, 4.2.3 and 4.3-rc5. SoC am335x 600MHz >>>>>> >>>>>> Below the USB topology: >>>>>> >>>>>> # lsusb -t >>>>>> /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=musb-hdrc/1p, 480M >>>>>> /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=musb-hdrc/1p, 480M >>>>>> |__ Port 1: Dev 2, If 0, Class=, Driver=hub/4p, 480M >>>>>> |__ Port 1: Dev 9, If 0, Class=, Driver=hub/4p, 480M >>>>>> |__ Port 1: Dev 10, If 0, Class=, Driver=ftdi_sio, 12M >>>>>> |__ Port 2: Dev 11, If 0, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 2: Dev 11, If 1, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 2: Dev 11, If 2, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 2: Dev 11, If 3, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 3: Dev 12, If 0, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 3: Dev 12, If 1, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 3: Dev 12, If 2, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 3: Dev 12, If 3, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 2: Dev 4, If 0, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 2: Dev 4, If 1, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 2: Dev 4, If 2, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 2: Dev 4, If 3, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 3: Dev 7, If 0, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 3: Dev 7, If 1, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 3: Dev 7, If 2, Class=, Driver=ftdi_sio, 480M >>>>>> |__ Port 3: Dev 7, If 3, Class=, Driver=ftdi_sio, 480M >>> >>> How many EPs does each FTDI device require? at least one INT EP, right? >>> If I read it right, the topology above has 2 hubs, and 16 high-speed >>> FTDI and 1 full-speed FTDI. So it requires at least 18 high-speed INT >>> EPs. MUSB driver only has 11 high-speed EPs for mode-4 which is the EP >>> configuration used by default. I am wondering how those devices got >>> enumerated properly. >> >> dynamic EP allocation, but that has its own limitations. >> > MUSB does not support dynamic EP allocation for INT/ISOCH. I remember isoc doesn't, not sure about int. Do you remember where that part of the code is off the top of your head ? -- balbi
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