Thank you the feedback. I think it may be any issue with spi interface and/or chip select config. [ 6.812079] DEBUG mcp251xfd mcp251xfd_probe(): ENTER [ 6.812174] mcp251xfd spi0.0: DEBUG mcp251xfd mcp251xfd_probe(): devm_clk_get() [ 6.812208] mcp251xfd spi0.0: DEBUG mcp251xfd mcp251xfd_probe(): feq=0x2625a00 [ 6.850106] mcp251xfd spi0.0 (unnamed net_device) (uninitialized): Failed to detect MCP251xFD (osc=0x00000000). This proves that the driver is getting the 40 MHz from the device tree properties. The board does have a 40 MHz osc. It is the Waveshare CANFD Hat [1]. They have their own tarball for download [2] with a mcp25xxfd driver that is copyright 2019 by Martin Sperl <kernel@xxxxxxxxxxxxxxxx>. I'm looking at that to see why it works and the newer, proper driver does not. Thanks, Drew [1] https://www.waveshare.com/wiki/2-CH_CAN_FD_HAT [2] https://www.waveshare.com/wiki/File:2-CH-CAN-FD-HAT-Demo.7z On Mon, Oct 26, 2020 at 12:00 PM Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> wrote: > > On 10/26/20 5:51 PM, Patrick Menschel wrote: > >> On 10/26/20 3:50 AM, Drew Fustini wrote: > >>> I'm seeing this message which makes me think my issue is that I am not > >>> setting the oscillator as a dtoverlay param. > >>> > >>> [ 6.873081] CAN device driver interface > >>> [ 6.879904] DEBUG mcp251xfd mcp251xfd_probe(): ENTER > >>> [ 6.880068] spi_master spi0: will run message pump with realtime priority > >>> [ 6.921312] mcp251xfd spi0.0 (unnamed net_device) (uninitialized): > >>> Failed to detect MCP251xFD (osc=0x00000000). > ^^^^^^^^^^ > > Contents of OSC register. > > >>> [pi4] > >>> dtoverlay=mcp251xfd-spi0-0 > >> > >> Are you using CS0 of spi0? > >> What's the frequency of your OSC? > > > > mcp251xfd_osc_invalid(osc) is true according to the string. > > > > https://github.com/marckleinebudde/linux/blob/v5.4-rpi/mcp251xfd-20201022-54/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c#L552 > > ACK > > The OSC register would never contain 0x0. So when reading 0x0 (or 0xff) you have > not read anything. This is what the "invalid" test does. > > This could have several reasons, e.g. mcp2518fd is not on SPI0 CS0, or the OSC > is 20 MHz, but the DT specifies an OSC of 40 MHz. > > Marc > > -- > Pengutronix e.K. | Marc Kleine-Budde | > Embedded Linux | https://www.pengutronix.de | > Vertretung West/Dortmund | Phone: +49-231-2826-924 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | >
