* Philip Balister <philip@xxxxxxxxxxxx> [090218 16:39]: > David Brownell wrote: >> On Tuesday 17 February 2009, Philip Balister wrote: >>> A number of people have tried using the McSPI3 interface with the >>> spidev driver. Running the spidev_test program shows data coming out >>> of the interface, but when we connect the SIMO to SOMI pins, the >>> spidev_test program shows only 0's. Someone tried wiring SOMI to >>> +volts and still only saw 0 read. >> >> I took a quick glance, and the pinmuxing looks sort of OK if >> you ignore the names ... use the right balls, not XXX: >> >> + AE2_3430_MCSPI3_CLK, >> + AG5_3430_MCSPI3_SIMO, >> + AH5_3430_MCSPI3_SOMI, >> + AF4_3430_MCSPI3_CS0, >> + AG4_3430_MCSPI3_CS1, >> >> I suggest you start with a more focussed patch, only setting >> up McSPI3. For one thing, the MMC2 pinmuxing will interfere >> with this set of MCSPI3 configurations. >> >> Also, start with a less aggressive bit rate than 48 MHz; that >> may be OK on a well designed board, but breadboards tend to >> show flakiness at much over 10 MHz. > > OK, more results: > > 1) I do not intend for this to go into the kernel, well unless there is > an outcry from beagle users :) Sure we should integrate it, people need it! > Steve Sakoman suggested I do the pinmux setup in u-boot and furnished me > with a small u-boot patch. Using this patch and removing the pinmux > stuff from the kernel patch lead to working spidev_test. The pin muxing should be also available in the kernel especially for boards that have multiple options for the pins. > The 48 MHz is the max rate, spidev_test defaults to 500 kHz. (but it > appears to work at 48 MHz also. > > Thanks for taking a look at this! How about add a cmdline option where you override the spi ports in use? > PS: I love photos: http://www.flickr.com/photos/32615155@N00/3291304854/ Hmm, I can't quite see from the photo where you have wired the cat's tail to.. :) Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
