Commit e5e3df06 authored by Frank Li's avatar Frank Li Committed by Alexandre Belloni
Browse files

i3c: add actual_len in i3c_priv_xfer 



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_len" field
to indicate how much get by i3c_priv_xfer.

Reviewed-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: default avatarFrank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20231201222532.2431484-4-Frank.Li@nxp.com


Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent 05b26c31

include/linux/i3c/device.h

+2 −0
Original line number Diff line number Diff line
@@ -54,6 +54,7 @@ enum i3c_hdr_mode { 
 * struct i3c_priv_xfer - I3C SDR private transfer

 * @rnw: encodes the transfer direction. true for a read, false for a write

 * @len: transfer length in bytes of the transfer

 * @actual_len: actual length in bytes are transferred by the controller

 * @data: input/output buffer

 * @data.in: input buffer. Must point to a DMA-able buffer

 * @data.out: output buffer. Must point to a DMA-able buffer
@@ -62,6 +63,7 @@ enum i3c_hdr_mode { 
struct i3c_priv_xfer {

	u8 rnw;

	u16 len;

	u16 actual_len;

	union {

		void *in;

		const void *out;