> > *Thank you very much about clarifying this point !* > > *I don't think that I can allocate enough time to dive into what John > described - I assume that at some stage there will be such a driver or > other form of such support* > > *Thanks for now* >
People have been discussing this since ~2009, and 2013, one person on the TI e2e forums claimed to have it working. One way to get it working however, would be to use a PRU to enable, and monitor the McSPI module. Passed that, I'd probably use uio to communicate between the McPSI module, and Linux. Would it be a simple task to get all this working properly ? I'm afraid that this would be over my head too, for now, but I had considered taking this on as a project at some point. Something that's a challenge always appeals to me . . . On Sun, Mar 27, 2016 at 11:14 PM, Yaron Yzhak Lederman < yaron.leder...@gmail.com> wrote: > Thank you very much about clarifying this point ! > > I don't think that I can allocate enough time to dive into what John > described - I assume that at some stage there will be such a driver or > other form of such support > > Thanks for now > > > > > > > On Sun, Mar 27, 2016 at 11:29 PM, John Syne <john3...@gmail.com> wrote: > >> The McSPI needs a driver and there is currently no Linux Driver that >> supports SPI slave mode. The current driver /drivers/spi/spi-omap2-mcspi.c >> does not support slave mode. The Linux kernel SPI framework uses >> spi-omap2-mcspi driver on TI processors. >> >> Regards, >> John >> >> >> >> >> On Mar 27, 2016, at 12:35 PM, William Hermans <yyrk...@gmail.com> wrote: >> >> I'd actually look into using the McSPI module. Which is hardware, and >> does support slave mode. >> >> On Sun, Mar 27, 2016 at 11:29 AM, John Syne <john3...@gmail.com> wrote: >> >>> Ah, what you are trying to do cannot be done with the current SPI driver >>> because Linux SPI framework does not support SPI slave mode. Recently >>> someone added I2C slave support to the I2C framework and that might be your >>> first place to look. My approach would be to create a custom SPI driver >>> that does not use the SPI framework. The length and frequency of messages >>> will define the driver design. For example, if the message length is >>> smaller than the SPI receive FIFO size, I would do this with interrupts, >>> but the interrupt would occur only when exceeding the FIFO threshold and >>> then dump the full FIFO in the bottom half interrupt handler. This way, you >>> would get an interrupt on every say every 32 receive bytes, which will >>> reduce the interrupt overhead and improve throughput. >>> >>> If the message length is more than the FIFO length, or if the message is >>> cyclical, then I would use DMA to copy the SPI data into a ping-pong buffer >>> arrangement. From the use space app, you would use poll to wait for a >>> complete buffer, and then read that buffer via read or mmap. >>> >>> Question is, how experienced are you at writing Linux drivers? This >>> isn’t a trivial task. >>> >>> Regards, >>> John >>> >>> >>> >>> >>> On Mar 27, 2016, at 12:26 AM, Yaron Yzhak Lederman < >>> yaron.leder...@gmail.com> wrote: >>> >>> John Hi, >>> >>> Thank you for coming back on this. >>> >>> I'm trying to connect 2 SPI busses on the BBB (HDMI disabled) and >>> configure SPI1 as SPI slave so that I can sent messages from SPI0 to SPI1 - >>> this allows me my application development and laterone I'll connect the >>> respective SPI slave and master devices >>> >>> Thank you >>> Yaron >>> >>> On Wed, Mar 23, 2016 at 10:37 PM, John Syne <john3...@gmail.com> wrote: >>> >>>> What exactly are you trying to do? Please explain your application so >>>> that we can propose a solution. >>>> >>>> Regards, >>>> John >>>> >>>> >>>> >>>> >>>> On Mar 23, 2016, at 4:29 AM, yaron.leder...@gmail.com wrote: >>>> >>>> Hi, >>>> >>>> Is there any resolution about this ? Since I'm having the same >>>> consideration >>>> >>>> Thanks ! >>>> >>>> >>>> On Wednesday, November 4, 2015 at 4:15:23 PM UTC+2, ravi...@gmail.com >>>> wrote: >>>>> >>>>> Hi, >>>>> >>>>> I'm trying to setup SPI slave mode with same above method and >>>>> changed OMAP2_MCSPI_MODULCTRL_MS set to 0 for slave mode. >>>>> >>>>> i'm facing issue in master mode and slave both on sckl pin >>>>> configuration. >>>>> >>>>> http://elinux.org/BeagleBone_Black_Enable_SPIDEV in this link why >>>>> sckl pin is configured as INPUT 0x33 but it will work with same >>>>> configuration if i change it to OUTPUT it doesn't work with any slave >>>>> device and no clock on that pin. >>>>> >>>>> Please anyone clarify this doubt and issues. >>>>> >>>>> For slave mode i tried to change OMAP2_MCSPI_MODULCTRL_MS bit in >>>>> driver file spi_omap2_mcspi.c but no use. still its master only. >>>>> >>>>> Please provide any suggestion or exact procedure. >>>>> >>>>> Thank you in advance. >>>>> >>>>> Regard s >>>>> Ravi >>>>> >>>>> On Thursday, September 18, 2014 at 5:45:47 AM UTC+5:30, >>>>> phil...@gmail.com wrote: >>>>>> >>>>>> >>>>>> I am having issues with SPI between two BBB that may be simple to >>>>>> solve. I have spidev_test loopback working on each board but am having >>>>>> problems connecting the two. >>>>>> >>>>>> spi0 master dts: >>>>>> 0x150 0x10 /* spi0_sclk, OUTPUT_PULLUP | MODE0 */ >>>>>> 0x154 0x30 /* spi0_d0, INPUT_PULLUP | MODE0 */ >>>>>> 0x158 0x10 /* spi0_d1, OUTPUT_PULLUP | MODE0 */ >>>>>> 0x15c 0x10 /* spi0_cs0, OUTPUT_PULLUP | MODE0 */ >>>>>> >>>>>> spi slave dts: >>>>>> 0x150 0x30 /* spi0_sclk, INPUT_PULLUP | MODE0 */ >>>>>> 0x154 0x10 /* spi0_d0, OUTPUT_PULLUP | MODE0 */ >>>>>> 0x158 0x30 /* spi0_d1, INPUT_PULLUP | MODE0 */ >>>>>> 0x15c 0x30 /* spi0_cs0, INPUT_PULLUP | MODE0 */ >>>>>> >>>>>> >>>>>> The oscilloscope shows activity when spi0_sckl (P9_17) is not >>>>>> connected but nothing when P9_17 is connected between both boards. >>>>>> I am sending bytes from master with the command: echo 1 > >>>>>> /dev/spidev1.0 >>>>>> >>>>>> I need 4-8mbit/sec transfer, is this achievable by bit banging over >>>>>> GPIO and would that be a viable alternative to getting SPI working? >>>>>> >>>>>> >>>> -- >>>> 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 beagleboard+unsubscr...@googlegroups.com. >>>> 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 a topic in the >>>> Google Groups "BeagleBoard" group. >>>> To unsubscribe from this topic, visit >>>> https://groups.google.com/d/topic/beagleboard/jQ1LH6IDH1A/unsubscribe. >>>> To unsubscribe from this group and all its topics, send an email to >>>> beagleboard+unsubscr...@googlegroups.com. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> >>> >>> -- >>> בברכה, >>> >>> ירון יצחק לדרמן >>> 08-6909594 >>> >>> -- >>> 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 beagleboard+unsubscr...@googlegroups.com. >>> 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 beagleboard+unsubscr...@googlegroups.com. >>> 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 beagleboard+unsubscr...@googlegroups.com. >> 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 a topic in the >> Google Groups "BeagleBoard" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/beagleboard/jQ1LH6IDH1A/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> beagleboard+unsubscr...@googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. >> > > > > -- > בברכה, > > ירון יצחק לדרמן > 08-6909594 > > -- > 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 beagleboard+unsubscr...@googlegroups.com. > 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. 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