Re: RPI4/8GB i2c not working?

Klaus Küchemann via freebsd-arm <[email protected]>
Newsgroups gmane.os.freebsd.devel.arm
Message-ID <[email protected]>
root@generic:~ # i2c -f /dev/iic0 -s -v
dev: /dev/iic0, addr: 0x40100401, r/w: r, offset: 0x00, width: 8, count: 1
Hardware may not support START/STOP scanning; trying less-reliable read method.

——

So the device is there ! ....

root@generic:~ # ktrace -t+ i2c -s -f /dev/iic0

root@generic:~ # kdump
....
1287 i2c      RET   open 3
  1287 i2c      CALL  read(0x3,0x4027cc18,0x80)
  1287 i2c      GIO   fd 3 read 128 bytes
       0x0000 4568 6e74 0100 0000 8000 0000 d500 0000  |Ehnt............|
       0x0010 0000 0000 d400 0000 0000 0000 0000 0000  |................|
       0x0020 0000 0000 0000 0000 0000 0000 0000 0000  |................|
       0x0030 0000 0000 0000 0000 0000 0000 0000 0000  |................|
       0x0040 0000 0000 0000 0000 0000 0000 0000 0000  |................|
       0x0050 0000 0000 0000 0000 0000 0000 0000 0000  |................|
       0x0060 0000 0000 0000 0000 0000 0000 0000 0000  |................|
       0x0070 0000 0000 0000 0000 0000 0000 0000 0000  |................|

—

successful GIO   fd 3 read looks quite good working !…


But then loops in the end :

1287 i2c      RET   ioctl -1 errno 35 Resource temporarily unavailable
  1287 i2c      CALL  ioctl(0x3,I2CRSTCARD,0xffffffffea70)
  1287 i2c      RET   ioctl 0
  1287 i2c      CALL  ioctl(0x3,I2CRDWR,0xffffffffe998)
  1287 i2c      RET   ioctl -1 errno 35 Resource temporarily unavailable
  1287 i2c      CALL  ioctl(0x3,I2CRSTCARD,0xffffffffea70)


since I don't have an i2c-gadget to test at the moment , can't say which device exactly 
supports START/STOP scanning and which not.

Also possibly some things cood depend on loaded overlays/config.txt 
and which corresponding GPIO-pins are configured 

K.

_______________________________________________
[email protected] mailing list
https://lists.freebsd.org/mailman/listinfo/freebsd-arm
To unsubscribe, send any mail to "[email protected]"
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.