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For example > > > on 64bit platforms, we reduce the size from 48 bytes to 32 bytes. > > > > > > Signed-off-by: Jisheng Zhang > > > --- > > > drivers/i3c/master/dw-i3c-master.c | 4 ++-- > > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c > > > index 6ba84a97765f..d6f84f0f4c2d 100644 > > > --- a/drivers/i3c/master/dw-i3c-master.c > > > +++ b/drivers/i3c/master/dw-i3c-master.c > > > @@ -247,10 +247,10 @@ struct dw_i3c_cmd { > > > u32 cmd_lo; > > > u32 cmd_hi; > > > u16 tx_len; > > > - const void *tx_buf; > > > u16 rx_len; > > > > only switch rx_len and tx_buf should be enough. otherwise there are data > > pad after u8 error. > > If we keep the error at the end of the struct, there's still padding > after the u8 error. > There's no big difference between current sol and only switch rx_len and > tx_buf on 32bit platforms. But on 64bit platforms, the current version > makes use of the pad to store the error, thus saves 8 byte more. Yes, I missed caculate. Reviewed-by: Frank Li > > Thanks > > > > Frank > > > > > - void *rx_buf; > > > u8 error; > > > + const void *tx_buf; > > > + void *rx_buf; > > > }; > > > > > > struct dw_i3c_xfer { > > > -- > > > 2.51.0 > > >