diff mbox series

[2/5] i3c: add actual in i3c_priv_xfer

Message ID 20231016154632.2851957-3-Frank.Li@nxp.com
State New
Headers
Series i3c: master: some improvment for i3c master |

Commit Message

Frank Li Oct. 16, 2023, 3:46 p.m. UTC 
  In MIPI I3C Specification:

"Ninth Bit of SDR Target Returned (Read) Data as End-of-Data: In I2C, the
ninth Data bit from Target to Controller is an ACK by the Controller. By
contrast, in I3C this bit allows the Target to end a Read, and allows the
Controller to Abort a Read. In SDR terms, the ninth bit of Read data is
referred to as the T-Bit (for ‘Transition’)"

I3C allow devices early terminate data transfer. So need "actual" field to
indicate how much get by i3c_priv_xfer.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 include/linux/i3c/device.h | 1 +
 1 file changed, 1 insertion(+)

Comments

Jarkko Nikula Oct. 17, 2023, 6:10 a.m. UTC | #1 
Hi

On 10/16/23 18:46, Frank Li wrote:
> In MIPI I3C Specification:
> 
> "Ninth Bit of SDR Target Returned (Read) Data as End-of-Data: In I2C, the
> ninth Data bit from Target to Controller is an ACK by the Controller. By
> contrast, in I3C this bit allows the Target to end a Read, and allows the
> Controller to Abort a Read. In SDR terms, the ninth bit of Read data is
> referred to as the T-Bit (for ‘Transition’)"
> 
> I3C allow devices early terminate data transfer. So need "actual" field to
> indicate how much get by i3c_priv_xfer.
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
>   include/linux/i3c/device.h | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/include/linux/i3c/device.h b/include/linux/i3c/device.h
> index 90fa83464f00..f2fa7ee5d96d 100644
> --- a/include/linux/i3c/device.h
> +++ b/include/linux/i3c/device.h
> @@ -66,6 +66,7 @@ struct i3c_priv_xfer {
>   		void *in;
>   		const void *out;
>   	} data;
> +	u16 actual;
>   	enum i3c_error_code err;
>   };
>   
Would this be more clear if named as "actual_len" and put next after 
"len" field in this structure? Also kerneldoc comment is missing.
diff mbox series

Patch

diff --git a/include/linux/i3c/device.h b/include/linux/i3c/device.h
index 90fa83464f00..f2fa7ee5d96d 100644
--- a/include/linux/i3c/device.h
+++ b/include/linux/i3c/device.h
@@ -66,6 +66,7 @@  struct i3c_priv_xfer {
 		void *in;
 		const void *out;
 	} data;
+	u16 actual;
 	enum i3c_error_code err;
 };