Hi Hans, 2018-02-07 20:00 GMT+08:00 Hans Verkuil <hverkuil@xxxxxxxxx>: > On 12/29/17 08:52, Shunqian Zheng wrote: >> From: Jeffy Chen <jeffy.chen@xxxxxxxxxxxxxx> >> >> Add the header for userspace > > General note: I saw four cases where this documentation referred to the > datasheet. Three comments on that: > > 1) You don't say which datasheet. > 2) I assume the datasheet is under NDA? This datasheet can't be got by customers, even under NDA. > 3) You do need to give enough information so a reasonable default can be > used. I mentioned in an earlier review that creating an initial params > struct that can be used as a templete would be helpful (or even > required), and that would be a good place to put such defaults. > It don't need a default config For applcation writers, they can just init it with zero data, and only set value for the part they concerned. As for ABI, i have checked there is no mismatches. Those structures is 32 bit aligned both in 64bit/32bit env, since there is no 64bit value. "__attribute__ ((packed))" can avoid mismatches happen when we add a 64bit value to those structures. As robin said, enums and bools are not guaranteed to be consistent between different compiler, so it's a potential risk. I have replace bools with unsigned char and enums with unsigned int. > Regards, > > Hans
