Re: [PATCH] i2c: virtio: add a virtio i2c frontend driver

Jason Wang
2020-09-09T08:54:58Z

On 2020/9/8 上午9:40, Jie Deng wrote:
>
>
> On 2020/9/7 13:40, Jason Wang wrote:
>>
>>>
>>>
>>>>
>>>>>
>>>>> +struct virtio_i2c_msg {
>>>>> +    struct virtio_i2c_hdr hdr;
>>>>> +    char *buf;
>>>>> +    u8 status;
>>>>
>>>>
>>>> Any reason for separating status out of virtio_i2c_hdr?
>>>>
>>> The status is not from i2c_msg.
>>
>>
>> You meant ic2_hdr? You embed status in virtio_i2c_msg anyway.
>>
>>
> The "i2c_msg" structure defined in i2c.h.
>
>>> So I put it out of virtio_i2c_hdr.
>>
>>
>> Something like status or response is pretty common in virtio request
>> (e.g net or scsi), if no special reason, it's better to keep it in
>> the hdr.
>>
> Mainly based on IN or OUT.
>
> The addr, flags and len are from "i2c_msg". They are put in one
> structure as an OUT**scatterlist.
> The buf can be an OUT**or an IN scatterlist depending on write or read.
> The status is a result from the backend  which is defined as an IN
> scatterlis.

Ok. I get this.

Thanks