Hi,

(please avoid top-posting)

On Fri, Feb 21, 2014 at 12:11:40AM +0000, Chris Kimber wrote:
> Hey,
> 
> Thanks for the response.
> 
> I've disabled the DMA (CONFIG_MUSB_PIO_ONLY=y) but the problem still
> persists (for both USB sticks & USB serial ports).

hmm, that's weird.

> Now it looks like dsps_interrupt() never fires and causes the hang
> up...
> 
> [   94.865635] tty ttyUSB0: serial_write - 11 byte(s)
> [   94.865656] cp210x ttyUSB0: usb_serial_generic_write_start - length = 11, data = 54 45 53 54 49 4e 47 20 34 32 0a
> [   94.865680] musb-hdrc musb-hdrc.1.auto: qh ce461a00 periodic slot 10
> [   94.865700] musb-hdrc musb-hdrc.1.auto: qh ce461a00 urb ce481e80 dev2 ep1out-bulk, hw_ep 10, ce43db00/11
> [   94.865721] musb-hdrc musb-hdrc.1.auto: --> hw10 urb ce481e80 spd2 dev2 ep1out h_addr00 h_port00 bytes 11
> [   94.865740] musb-hdrc musb-hdrc.1.auto: TX ep10 fifo d0832c48 count 11 buf ce43db00
> [   94.865755] musb-hdrc musb-hdrc.1.auto: Start TX10 pio
> [   94.865792] musb-hdrc musb-hdrc.1.auto: usbintr (0) epintr(400)
> [   94.865810] musb-hdrc musb-hdrc.1.auto: ** IRQ host usb0000 tx0400 rx0000
> [   94.865826] musb-hdrc musb-hdrc.1.auto: OUT/TX10 end, csr 2100
> [   94.865866] musb-hdrc musb-hdrc.1.auto: complete ce481e80 usb_serial_generic_write_bulk_callback+0x0/0xd4 [usbserial] (0), dev2 ep1out, 11/11

so the first one completed just fine.

> [   94.865971] tty ttyUSB0: serial_write - 11 byte(s)
> [   94.865991] cp210x ttyUSB0: usb_serial_generic_write_start - length = 11, data = 54 45 53 54 49 4e 47 20 34 33 0a
> [   94.866015] musb-hdrc musb-hdrc.1.auto: qh ce461a00 periodic slot 10
> [   94.866035] musb-hdrc musb-hdrc.1.auto: qh ce461a00 urb ce481e80 dev2 ep1out-bulk, hw_ep 10, ce43db00/11
> [   94.866055] musb-hdrc musb-hdrc.1.auto: --> hw10 urb ce481e80 spd2 dev2 ep1out h_addr00 h_port00 bytes 11
> [   94.866075] musb-hdrc musb-hdrc.1.auto: TX ep10 fifo d0832c48 count 11 buf ce43db00
> [   94.866089] musb-hdrc musb-hdrc.1.auto: Start TX10 pio

can you dump TXCSR, DEVCTL and IRQ registers when this happens ?

-- 
balbi