On Wed, Apr 03, 2019 at 05:52:20PM +0200, Paul Cercueil wrote: > > > Le mer. 3 avril 2019 à 17:46, Bin Liu <b-liu@xxxxxx> a écrit : > >On Wed, Apr 03, 2019 at 05:31:31PM +0200, Paul Cercueil wrote: > >> > >> > >> Le mer. 3 avril 2019 à 15:26, Bin Liu <b-liu@xxxxxx> a écrit : > >> >On Tue, Apr 02, 2019 at 09:58:42PM +0200, Paul Cercueil wrote: > >> >> Hi, > >> >> > >> >> Le lun. 1 avril 2019 à 20:20, Bin Liu <b-liu@xxxxxx> a écrit : > >> >> >On Mon, Apr 01, 2019 at 07:46:22PM +0200, Paul Cercueil wrote: > >> >> >> > >> >> >> > >> >> >> Le lun. 1 avril 2019 à 19:17, Bin Liu <b-liu@xxxxxx> a > >>écrit : > >> >> >> >On Thu, Mar 21, 2019 at 03:42:46PM +0100, Paul Cercueil > >>wrote: > >> >> >> >> When the musb is shutdown, for instance when the driver is > >> >> >>unloaded, > >> >> >> >> force-disable the pullup. Otherwise, the host will > >>still see > >> >> >> >>the gadget > >> >> >> >> device even after the shutdown. > >> >> >> > > >> >> >> >how would this happen? > >> >> >> > > >> >> >> >when musb-hdrc driver is unloaded, udc core removes the bound > >> >> >>gadget > >> >> >> >driver which calls musb_gadget_pullup() to disable the > >>pullup. > >> >> >> > >> >> >> I'm testing with the jz4740-musb driver. I don't unload the > >> >> >>module (it's > >> >> >> built-in) but unbind it from sysfs. > >> >> > > >> >> >I did unbind too. > >> >> > > >> >> >root@am335x-evm:/sys/bus/platform/drivers/musb-hdrc# echo > >> >> >musb-hdrc.0 > unbind > >> >> > > >> >> >or unbind the glue driver: > >> >> > > >> >> >root@am335x-evm:/sys/bus/platform/drivers/musb-dsps# echo > >> >> >47401400.usb > unbind > >> >> > > >> >> >musb_gadget_pullup() is called in both cases. > >> >> > > >> >> >[ 3880.597014] [<bf444ab0>] (musb_gadget_pullup > >>[musb_hdrc]) from > >> >> >[<bf402cbc>] (usb_gadget_disconnect+0x3c/0xf4 [udc_core]) > >> >> >[ 3880.607959] [<bf402cbc>] (usb_gadget_disconnect [udc_core]) > >> >> >from [<bf403b28>] (usb_gadget_remove_driver+0x4c/0x90 > >>[udc_core]) > >> >> >[ 3880.619338] [<bf403b28>] (usb_gadget_remove_driver > >>[udc_core]) > >> >> >from [<bf403d20>] (usb_del_gadget_udc+0x5c/0xc0 [udc_core]) > >> >> > >> >> In my case this stops here, usb_del_gadget_udc() does not call > >> >> usb_gadget_remove_driver(), that's why the pullup is never > >>disabled. > >> >> > >> >> I guess that's because udc->driver is NULL; I'm testing with > >> > > >> >then the pullup should be disable by now. > >> > > >> >> CONFIG_USB_CONFIGFS, > >> >> and I don't configure anything in sysfs before unbinding the > >>driver. > >> > > >> >I didn't check on this, but I could imagine that > >> >- when a configfs gadget is bound to the udc, .pullup() is called; > >> >- when the configfs gadget is unbound from the udc, .pullup > >>should be > >> > called again to disable the pullup. > >> > >> An important thing that I did not mention, is that the SoC boots > >> from USB, > >> so the pullup is active before the musb driver loads. Since in > >>my case a > > > >It sounds to me that the musb driver should disable the pullup during > >init. Isn't it? > > Yes. I can move it to musb_gadget_setup(). Should I still protect it > with > the spinlock then? Thanks. I don't think spinlock is necessary here. -Bin.
