On Thu, Aug 22, 2019 at 05:45:17PM +0800, Hsin-Yi Wang wrote: > When doing i2cdetect quick write mode, we would get transfer > error ENOMEM, and i2cdetect shows there's no device at the address. > Quoting from mt8183 datasheet, the number of transfers to be > transferred in one transaction should be set to bigger than 1, > so we should forbid zero-length transfer and update functionality. > > Incorrect return: > localhost ~ # i2cdetect -q -y 0 > 0 1 2 3 4 5 6 7 8 9 a b c d e f > 00: -- -- -- -- -- -- -- -- -- -- -- -- -- > 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 70: -- -- -- -- -- -- -- -- > > After this patch: > localhost ~ # i2cdetect -q -y 0 > Error: Can't use SMBus Quick Write command on this bus > > localhost ~ # i2cdetect -y 0 > Warning: Can't use SMBus Quick Write command, will skip some addresses > 0 1 2 3 4 5 6 7 8 9 a b c d e f > 00: > 10: > 20: > 30: -- -- -- -- -- -- -- -- > 40: > 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- > 60: > 70: Thanks for providing these test results. Much appreciated. To shorten the commit log a little, I removed them before applying, though. > > Reported-by: Alexandru M Stan <amstan@xxxxxxxxxxxx> > Signed-off-by: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx> Applied to for-next, thanks!
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