Re: [PATCH 02/12] i2c: designware-master: use core to detect 'no zero length' quirk

[Jarkko Nikula]

On 07/23/2018 11:26 PM, Wolfram Sang wrote:
> And don't reimplement in the driver.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
> ---
>
> Only build tested.
>
>   drivers/i2c/busses/i2c-designware-master.c | 12 +++++-------
>   1 file changed, 5 insertions(+), 7 deletions(-)
I tested this with patch 1 and I like it since with these patches the 
test is done before firing up the HW, waiting for an interrupt and then 
see the length is invalid for us.

i2ctransfer -f 8 r0@0x10

Before (with i2c_designware debugging on):
[   15.607283] i2c_designware i2c_designware.1: i2c_dw_xfer: msgs: 1
[   15.711988] i2c_designware i2c_designware.1: enabled=0x1 stat=0x10
[   15.712002] i2c_designware i2c_designware.1: i2c_dw_xfer_msg: invalid 
message length
Error: Sending messages failed: Invalid argument

After:
[   25.838661] i2c i2c-8: adapter quirk: no zero length (addr 0x0010, 
size 0, read)
Error: Sending messages failed: Operation not supported

Tested-by: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>
Acked-by: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>