On 03-03-21, 16:46, Jie Deng wrote: > This is not a problem. My original proposal was to mirror the struct > i2c_msg. > The code you looked at was based on that. > However, the virtio TC prefer not to mirror it. They have some concerns. > For example, there is a bit I2C_M_RD in i2c_msg.flag which has the same > meaning with > the R/W in virtio descriptor. This is a repetition which may cause problems. > So the virtio_i2c_out_hdr.flags is used to instead of i2c_msg.flags for > extension. So by default we don't support any of the existing flags except I2C_M_RD? #define I2C_M_TEN 0x0010 /* this is a ten bit chip address */ #define I2C_M_RD 0x0001 /* read data, from slave to master */ #define I2C_M_STOP 0x8000 /* if I2C_FUNC_PROTOCOL_MANGLING */ #define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_NOSTART */ #define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */ #define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */ #define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */ #define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */ How do we work with clients who want to use such flags now ? -- viresh
