[PATCH v3 0/3] i3c: Improve CCC reliability for DesignWare master

From: tze.yee.ng@altera.com
To: Alexandre Belloni <alexandre.belloni@bootlin.com>,
	Frank Li <Frank.Li@nxp.com>,
	Adrian Ng Ho Yin <adrian.ho.yin.ng@altera.com>,
	Felix Gu <ustc.gu@gmail.com>,
	Wolfram Sang <wsa+renesas@sang-engineering.com>,
	Manikanta Guntupalli <manikanta.guntupalli@amd.com>,
	Jorge Marques <jorge.marques@analog.com>,
	Sakari Ailus <sakari.ailus@linux.intel.com>,
	linux-i3c@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: [PATCH v3 0/3] i3c: Improve CCC reliability for DesignWare master
Date: Wed, 10 Jun 2026 18:54:05 -0700	[thread overview]
Message-ID: <cover.1781142158.git.tze.yee.ng@altera.com> (raw)

From: Tze Yee Ng <tze.yee.ng@altera.com>

Improve I3C CCC handling on the DesignWare master used on SoCFPGA
platforms: report the actual GET payload length, map hardware errors
to I3C M0/M2, and validate GET responses with a single retry for
transient failures.

Patch 1/3 fixes a DW driver bug: on successful GET CCC, set
dests[0].payload.len from RESPONSE_PORT_DATA_LEN.

Patch 2/3 maps DesignWare response-queue errors to ccc->err (M2 for
IBA/address NACK; M0 for CRC/parity/frame/transfer-abort).

Patch 3/3 moves protocol handling into the I3C core: validate GET
payload length (GETMRL: 2 or 3 bytes; GETMXDS: 2 or 5 bytes), retry
GET CCCs once on M0/M2, restore requested payload.len on retry/error,
and use a stack buffer for the common single-destination GET case.

Changes in v3:
- In dw_i3c_master_end_xfer_locked(), move RESPONSE_ERROR_ADDRESS_NACK to
  return -EIO.

Changes in v2:
- Split the monolithic patch into three patches (per review feedback).
- Move GET payload validation and CCC retry from the DW driver to
  drivers/i3c/master.c.
- Validate GET CCCs only; drop SET payload-length checks (DW
  RESPONSE_PORT_DATA_LEN is 0 on SET).
- Retry GET CCCs only; do not repeat side-effecting SET CCCs.
- Tighten GETMRL validation to exactly 2 or 3 bytes; add GETMXDS
  2/5-byte handling.
- Expand M0 mapping to CRC/parity/transfer-abort, not only frame
  errors.
- Restore dests[].payload.len before retry and on error return.
- Avoid kmalloc on the common single-destination GET path.

Adrian Ng Ho Yin (3):
  i3c: master: dw: Report actual GET CCC payload length on success
  i3c: master: dw: Map CCC hardware errors to I3C M0/M2
  i3c: master: Validate GET CCC payload length and retry M0/M2 once

 drivers/i3c/master.c               | 111 ++++++++++++++++++++++++++++-
 drivers/i3c/master/dw-i3c-master.c |  41 +++++++++--
 2 files changed, 144 insertions(+), 8 deletions(-)

-- 
2.43.7

-- 
linux-i3c mailing list
linux-i3c@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-i3c