Hello Peter, On Thu, Jan 23, 2014 at 09:22:41AM +0800, Peter Chen wrote: > On Wed, Jan 22, 2014 at 10:41:33PM +0100, Uwe Kleine-König wrote: > > On Wed, Jan 22, 2014 at 10:49:51AM +0100, Uwe Kleine-König wrote: > > > On Tue, Dec 03, 2013 at 04:01:50PM +0800, Chris Ruehl wrote: > > > > usb: chipidea: hw_phymode_configure moved before ci_usb_phy_init > > > > hw_phymode_configure configures the PORTSC registers and allow the > > > > following phy_inits to operate on the right parameters. This fix a problem > > > > where the UPLI (ISP1504) could not detected, because the Viewport was not > > > > available and read the viewport return 0's only. > > > This patch (or a later revision of it to be more exact) made it into > > > mainline as cd0b42c2a6d2. > > > > > > On an i.MX27 based machine I'm hitting an oops (see below) on > > > next-20140116 + a few patches. (I didn't switch to 3.13+ yet, as I think > > > not everything I need has landed there.) The oops goes away (and still > > > better, lsusb reports my connected devices instead of "unable to > > > initialize libusb: -99") when I do at least one of the following: > > > > > > - set CONFIG_USB_CHIPIDEA=y instead of =m > > > - revert commit > > > cd0b42c2a6d2 (usb: chipidea: put hw_phymode_configure before ci_usb_phy_init) > > I debugged that a bit further and the problem is that > > hw_phymode_configure depends on the phy's clk being enabled (i.e. > > usb_ipg_gate) and this is only enforced in ci_usb_phy_init (via > > usb_phy_init -> usb_gen_phy_init). When CONFIG_USB_CHIPIDEA=y the init > > call to disable all unused clocks wasn't run yet and so the clock is > > still on as this is the boot default. > > I am a little puzzled at your platform > > - Which phy you have used? ulpi phy ,internal phy or other external phy? I'm using an ISP1504 (i.e. ULPI) phy. > - If you use ulpi phy, why you still need to use nop phy driver? I don't need to, that's just how I made it running. If you have a better suggestion, don't hesitate to tell me. :-) > Besides, according to chris patch, the ulpi can only be visited after > hw_phymode_configure? It seems so, yes. For writing the PORTSC register the usb_ipg_gate clock must be on. hw_phymode_configure writes the register and ci_usb_phy_init enables the clock. > - Do you have some hardware related operation at phy's probe? If it exists, > why not move it to phy->init? I guess that would work and the culprit is that I just took Chris' patch because I don't have a clue about USB. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ | -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
