Re: Review request for D56251 - linux: add Linux i2c-dev ioctl compatibility support

thanks! i took a quick look, it looks good!


-a

On Sat, 11 Apr 2026 at 20:16, Yao Xin <[email protected]> wrote:
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> Hello FreeBSD developers,
>
>
>
> I would like to kindly request a review for the following Differential revision D56251:
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> linux: add Linux i2c-dev ioctl compatibility support
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>
>
> This change is for Linux application to communicate with monitor using DDC/CI interface (I2C) on FreeBSD.
>
> And tested by this tool ilovegrape/ddcci and the output is as below.
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>
>
> If you have time, I would appreciate any feedback, comments, or review on this change.
>
>
>
> Thank you for your time.
>
>
>
> root@FreeBSD:~ # ./DellDevice
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> i2c_write: ioctl returned -1, ioctl() error No such device or address
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> Reading EDID 0x50@/dev/iic0 failed.
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> Failed to get monitor info from /dev/iic0
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> i2c_write: ioctl returned -1, ioctl() error No such device or address
>
> Reading EDID 0x50@/dev/iic1 failed.
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> Failed to get monitor info from /dev/iic1
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> 0000: 00 ff ff ff ff ff ff 00 10 ac df 42 4c 50 35 48 | ...........BLP5H
>
> 0010: 0f 21 01 04 b5 3c 22 78 39 62 a5 ad 50 46 ab 24 | .!...<"x9b..PF.$
>
> 0020: 0e 50 54 a5 4b 00 71 4f 81 80 a9 40 d1 c0 81 c0 | .PT.K.qO...@....
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> 0030: a9 c0 01 01 01 01 56 5e 00 a0 a0 a0 29 50 30 20 | ......V^....)P0
>
> 0040: 35 00 55 50 21 00 00 1a 00 00 00 ff 00 43 4e 30 | 5.UP!........CN0
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> 0050: 37 33 4b 30 0a 20 20 20 20 20 00 00 00 fc 00 44 | 73K0.     .....D
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> 0060: 45 4c 4c 20 55 32 37 32 34 44 45 0a 00 00 00 fd | ELL U2724DE.....
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> 0070: 00 30 78 b2 b2 3c 01 0a 20 20 20 20 20 20 01 ad | .0x..<..      ..
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> isDellDevice: DEL
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> Control 0xc8: +/38921/39
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> Control 0xc9: +/16645/65535
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> Control 0xfd: +/116/255
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> Fetched value: C8_value = 38921, C9_value = 16645, FD_value = 116
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>
>
> getScalar(C8_value = 38921) = "3"
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> getSICode(FD_value = 116) = "T"
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> getFWStage_H(C9_value = 16645) = "M"
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>    C9High = "1"
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> getFWStage_L(C9_value = 16645, FD_value = 116) = "05"
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> Model = DELL U2724DE
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> Serial = CN073K0
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> Firmware Version = M3T105
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>
>
> /dev/iic10: Model = U2724DE, Serial = CN073K0, Firmware Version = M3T105
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> i2c_write: ioctl returned -1, ioctl() error Connection timed out
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> Reading EDID 0x50@/dev/iic11 failed.
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> Failed to get monitor info from /dev/iic11
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> i2c_write: ioctl returned -1, ioctl() error No such device or address
>
> Reading EDID 0x50@/dev/iic2 failed.
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> Failed to get monitor info from /dev/iic2
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> i2c_write: ioctl returned -1, ioctl() error Resource temporarily unavailable
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> Reading EDID 0x50@/dev/iic3 failed.
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> Failed to get monitor info from /dev/iic3
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> i2c_write: ioctl returned -1, ioctl() error Resource temporarily unavailable
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> Reading EDID 0x50@/dev/iic4 failed.
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> Failed to get monitor info from /dev/iic4
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> i2c_write: ioctl returned -1, ioctl() error Resource temporarily unavailable
>
> Reading EDID 0x50@/dev/iic5 failed.
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> Failed to get monitor info from /dev/iic5
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> i2c_write: ioctl returned -1, ioctl() error Resource temporarily unavailable
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> Reading EDID 0x50@/dev/iic6 failed.
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> Failed to get monitor info from /dev/iic6
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> i2c_write: ioctl returned -1, ioctl() error Resource temporarily unavailable
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> Reading EDID 0x50@/dev/iic7 failed.
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> Failed to get monitor info from /dev/iic7
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> i2c_write: ioctl returned -1, ioctl() error Resource temporarily unavailable
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> Reading EDID 0x50@/dev/iic8 failed.
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> Failed to get monitor info from /dev/iic8
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> i2c_write: ioctl returned -1, ioctl() error Connection timed out
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> Reading EDID 0x50@/dev/iic9 failed.
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> Failed to get monitor info from /dev/iic9
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>
>
>
>
> Regards,
>
> Xin