Messages in this thread Patch in this message | | | From | Frank Li <> | Subject | [PATCH v2 3/6] i3c: add actual_len in i3c_priv_xfer | Date | Wed, 18 Oct 2023 16:59:26 -0400 |
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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.
Signed-off-by: Frank Li <Frank.Li@nxp.com> --- include/linux/i3c/device.h | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/include/linux/i3c/device.h b/include/linux/i3c/device.h index 90fa83464f003..ef6217da8253b 100644 --- a/include/linux/i3c/device.h +++ b/include/linux/i3c/device.h @@ -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; -- 2.34.1
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