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I2C Interface (Header P22) - I can`t use this interface.

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Hi. nice to meet you.

I don`t speak english very well.
please, understand it.

I use Digi ConnectCore i.mx51.

I want use I2C interface(Header P22).
(Connect to PCA9554 expander)

I have next setting setp.

1)setting to kernel config.
device driver -> GPIO support -> PCA953x, PCA955x, TCA64xx, and MAX7310 I/O ports
device driver -> i2c support -> i2c system bus driver -> mxc i2c support
device driver -> i2c support -> i2c device interface
system type -> Freescale MXC Implementations -> I2C interface optoin -> Enable I2C1 module
system type -> Freescale MXC Implementations -> I2C interface optoin -> Enable I2C2 module

2)testing in board.(I use i2c-tools)
Explan to english is very hard.
so, See you that I input command.

[root /]# ls /dev/i2c-* -al
crw-rw---- 1 root root 89, 0 Jan 4 23:26 /dev/i2c-0
crw-rw---- 1 root root 89, 1 Jan 4 23:26 /dev/i2c-1

[root /]# i2cdetect -l
i2c-0 i2c mxc_i2c I2C adapter
i2c-1 i2c mxc_i2c I2C adapter

[root /]# i2cdetect 0
WARNING! This program can confuse your I2C bus, cause data loss and worse!
I will probe file /dev/i2c-0.
I will probe address range 0x03-0x77.

Continue? [Y/n]
0 1 2 3 4 5 6 7 8 i2c-adapter i2c-0: Bus Arbitration lost
9 a b c d e f
00: i2c-adapter i2c-0: Could not grab Bus ownership
-- i2c-adapter i2c-0: Bus Arbitration lost
i2c-adapter i2c-0: Could not grab Bus ownership
-- i2c-adapter i2c-0: Bus Arbitration lost
.........
-- i2c-adapter i2c-0: Bus Arbitration lost
i2c-adapter i2c-0: Could not grab Bus ownership
-- i2c-adapter i2c-0: Bus Arbitration lost
i2c-adapter i2c-0: Could not grab Bus ownership

[root /]# i2cdetect 1
WARNING! This program can confuse your I2C bus, cause data loss and worse!
I will probe file /dev/i2c-1.
I will probe address range 0x03-0x77.
Continue? [Y/n] y
0 1 2 3 4 5 6 7 8 i2c-adapter i2c-1: Could not grab Bus ownership
9 a b c d e f
00: i2c-adapter i2c-1: Could not grab Bus ownership
-- -- i2c-adapter i2c-1: Could not grab Bus ownership
-- i2c-adapter i2c-1: Could not grab Bus ownership
............
-- i2c-adapter i2c-1: Could not grab Bus ownership

[root /]# find /sys/bus/i2c/drivers
/sys/bus/i2c/drivers
/sys/bus/i2c/drivers/dummy
/sys/bus/i2c/drivers/dummy/uevent
/sys/bus/i2c/drivers/dummy/unbind
/sys/bus/i2c/drivers/dummy/bind
/sys/bus/i2c/drivers/dev_driver
/sys/bus/i2c/drivers/dev_driver/uevent
/sys/bus/i2c/drivers/dev_driver/unbind
/sys/bus/i2c/drivers/dev_driver/bind
/sys/bus/i2c/drivers/pca953x
/sys/bus/i2c/drivers/pca953x/module
/sys/bus/i2c/drivers/pca953x/uevent
/sys/bus/i2c/drivers/pca953x/unbind
/sys/bus/i2c/drivers/pca953x/bind

[root /]# find /sys/bus/i2c/devices/
/sys/bus/i2c/devices/

[root /]# cat /proc/devices
Character devices:
1 mem
4 /dev/vc/0
4 tty
5 /dev/tty
5 /dev/console
5 /dev/ptmx
7 vcs
10 misc
13 input
29 fb
89 i2c
90 mtd
108 ppp
128 ptm
136 pts
153 spi
180 usb
189 usb_device
207 ttymxc
252 mxc_vpu
253 mxc_ipu
254 rtc

Block devices:
259 blkext
7 loop
8 sd
31 mtdblock
65 sd
66 sd
67 sd
68 sd
69 sd
70 sd
71 sd
128 sd
129 sd
130 sd
131 sd
132 sd
133 sd
134 sd
135 sd
179 mmc

[root /]# i2cset 1 0x40 0x00 0x00
WARNING! This program can confuse your I2C bus, cause data loss and worse!
I will write to device file /dev/i2c-1, chip address 0x40, data address
0x00, data 0x00, mode byte.
Continue? [Y/n] y
i2c-adapter i2c-1: Could not grab Bus ownership
Error: Write failed

and, I tested next module. but not work.
kernel/drivers/i2c/busses/i2c-gpio.ko
kernel/drivers/i2c/busses/mxc_i2c.ko
kernel/drivers/i2c/algos/i2c-algo-bit.ko
kernel/drivers/i2c/i2c-dev.ko
kernel/drivers/i2c-slave/i2c_slave.ko
kernel/drivers/i2c-slave/mxc_i2c_slave.ko
kernel/drivers/i2c-slave/i2c_slave_client.ko

I think,
I2C interface(header P22) setting is GPIO.
so,can`t connect PCA9554 expander.
(it is Just my think)

I want really it!
(PCA9554 expander connect to I2C interface header P22, and PCA9554 control.)

do you any have idea?

help me please~~
asked Sep 14, 2010 in Linux by song0369 New to the Community (0 points)
recategorized Dec 3, 2013 by tuxembb

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