about i2cset tool

[Brandon Wyman]

On 2020-05-19 02:40, zhouyuanqing8 at outlook.com wrote:
> Hi All
>
>     I use the i2cget to read the device data, but the i2cset did not 
> write the data to the device, and the operation of i2cset did not 
> report any errors.
>
> for example:
>
> root at starlake-bmc:/usr/sbin# i2cget 9 0x10 0x00 i 3
> WARNING! This program can confuse your I2C bus, cause data loss and worse!
> I will read from device file /dev/i2c-9, chip address 0x10, data address
> 0x00, 3 bytes using read I2C block data.
> Continue? [Y/n]
> 3: 0x02 0x32 0xcc
>
> root at starlake-bmc:/usr/sbin# i2cset 9 0x10 0x82 0x0101 2
> WARNING! This program can confuse your I2C bus, cause data loss and worse!
> I will read from device file /dev/i2c-9, chip address 0x10, data address
> 0x00, using read word data.

Well, that is a bit odd. It looks like that just did a read, not a write.


Do you need to use the force access option? What is that 2? Should it be 
a word (w)?

https://linux.die.net/man/8/i2cset

i2cset -f 9 0x10 0x82 0x0101 w

>
> when I check the 0x82 reg，the value is not changed.
>
> Thanks
> harley
>
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