I don't think this got merged, but yeah spi slave support needs some work.
https://lwn.net/Articles/700433/ Regards, On Nov 3, 2017 9:10 PM, "Kenny Koller" <[email protected]> wrote: > I am reading the SPI docs that came with the kernel source. It looks like > this driver only supports being a master and not a slave? > > On Friday, November 3, 2017 at 6:51:36 PM UTC-7, Kenny Koller wrote: >> >> >> At the moment our design connects a UART between the Beaglebone and an >> STM32F4. I'd like to add support to receive data from the STM32F4 using >> SPI. It will require receiving frames of at least 64 kB each second so a 1 >> MHz clock should be adequate. I'm using the 3.8.13 kernel. >> >> Some questions: >> >> Some search results suggested that the SPI driver was a kernel extension >> but I was unable to find a corresponding spidev.ko in my filesystem or see >> it listed with lsmod. Does this mean that the device driver has been >> compiled in to the kernel? >> >> If it has been compiled within the kernel am I correct in thinking that >> I'll need to rebuild the kernel and adjust the buffer size. I think the >> default is 4096 and I would like it to be able to hold an entire >> transaction. >> >> Finally, I'm in the process of verifying the use of SPI0. I've compiled a >> device tree file (I'm using the one from ADA Fruit) and it seems to load >> properly: >> >> $ echo ADA-SPI0-01 > /sys/devices/bone_capemgr.9/slots >> $ ls /dev/spi* >> /dev/spidev1.0 /dev/spidev1.1 >> >> I downloaded the kernel source and compiled >> Documentation/spi/spidev_test.c for 3.8.13. >> >> I've jumpered pins 18 and 21 but I'm only seeing zeros: >> >> $ ./spidev_test /dev/spidev1.0 >> spi mode: 0 >> bits per word: 8 >> max speed: 500000 Hz (500 KHz) >> >> >> 00 00 00 00 00 00 >> 00 00 00 00 00 00 >> 00 00 00 00 00 00 >> 00 00 00 00 00 00 >> 00 00 00 00 00 00 >> 00 00 00 00 00 00 >> 00 00 >> >> I am not see the SPI pins listed in the pingroups as some posts have >> suggested: >> >> cat /sys/kernel/debug/pinctrl/44e10800.pinmux/pingroups >> >> Is editing uEnv.txt and a reboot required to properly configure things? >> When I tried adding the overlay to the kernel parameters the device nodes >> were not created. I modified in the following way: >> >> optargs=capemgr.disable_partno=BB-BONELT-HDMI,BB-BONELT-HDMIN capemgr. >> enable_partno=BB-UART5,ADA-SPI0-01 omap_wdt.nowayout=0 >> >> >> -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit https://groups.google.com/d/ > msgid/beagleboard/ba30c445-6367-468d-bccd-6a9945844729%40googlegroups.com > <https://groups.google.com/d/msgid/beagleboard/ba30c445-6367-468d-bccd-6a9945844729%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CAOCHtYgd5LYAjeLeNL3u2eTPcm-QGBPn%2Bpfo0Y3oPxxKdTsVWg%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
