Fabio Estevam <festevam@xxxxxxxxx> writes: Hi, > Hi Igor, > > [Adding linux-arm-kernel] > > On Tue, Dec 14, 2010 at 11:16 AM, Igor Grinberg <grinberg@xxxxxxxxxxxxxx> wrote: >> Hi Fabio, >> >> On 12/14/10 00:14, Fabio Estevam wrote: >>> Hi, >>> >>> I am working on adding USB OTG host support for the mx31_3ds board >>> (OTG PHY is a ISP1504). >> >> ISP1504 seems like ULPI compliant transceiver. >> >>> USB OTG in device mode works fine and I can only get OTG host mode to >>> work if I force a 'return 0' into the ulpi_check_integrity function. I >>> was wondering if anyone has any suggestions as to where to >>> inspect/debug the fact that the read/write to the OTG PHY scratch >>> register does not match. >> >> Both ULPI specifications (1.0 and 1.1) define the Scratch register as: >> "an empty register byte for testing purposes. Software can read, write, >> set and clear this register; and the functionality of the PHY will not be affected." >> Therefore it should be implemented in the ISP1504 as such and according to >> NXP's ISP1504 datasheet it should be there... >> >> What about the ID? Do you get the vendor/product ID value as expected? > > No, I am getting only zeros when reading vendor/product ID: > > ULPI transceiver vendor/product ID 0x0000/0x0000 > > Even though the ULPI integrity check fails, if I force a 'return 0' in > this function, then I am able to mount a USB stick and it is > functional. > > There are other i.MX boards that support OTG in host mode via ULPI, > such as pcm037, pca100, imx27_visstrim . > > I am curious to know if any of this boards can work in host mode OTG > with current mainline kernel. I guess you need to configure portsc register into ulpi mode in the .init function of the mxc_usbh_platform_data otherwise, you won't be able to reach the ulpi. Thanks, Arnaud -- 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
