kernel/linux.git/drivers/i3c/master.c, branch v6.18.22

i3c: master: Update hot-join flag only on success

2026-02-26T22:58:57+00:00

[ Upstream commit f0775157b9f9a28ae3eabc8d05b0bc52e8056c80 ] To prevent inconsistent state when an error occurs, ensure the hot-join flag is updated only when enabling or disabling hot-join succeeds. Fixes: 317bacf960a48 ("i3c: master: add enable(disable) hot join in sys entry") Signed-off-by: Adrian Hunter Reviewed-by: Frank Li Link: https://patch.msgid.link/20260113072702.16268-4-adrian.hunter@intel.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin

i3c: Move device name assignment after i3c_bus_init

2026-02-26T22:58:57+00:00

[ Upstream commit 3502cea99c7ceb331458cbd34ef6792c83144687 ] Move device name initialization to occur after i3c_bus_init() so that i3cbus->id is guaranteed to be assigned before it is used. Fixes: 9d4f219807d5 ("i3c: fix refcount inconsistency in i3c_master_register") Signed-off-by: Billy Tsai Reviewed-by: Frank Li Link: https://patch.msgid.link/20260112-upstream_i3c_fix-v1-1-cbbf2cb71809@aspeedtech.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin

i3c: fix refcount inconsistency in i3c_master_register

2025-12-18T13:02:44+00:00

[ Upstream commit 9d4f219807d5ac11fb1d596e4ddb09336b040067 ] In `i3c_master_register`, a possible refcount inconsistency has been identified, causing possible resource leak. Function `of_node_get` increases the refcount of `parent->of_node`. If function `i3c_bus_init` fails, the function returns immediately without a corresponding decrease, resulting in an inconsistent refcounter. Move call i3c_bus_init() after device_initialize() to let callback i3c_masterdev_release() release of_node. Reported-by: Shuhao Fu Closes: https://lore.kernel.org/linux-i3c/aO2tjp_FsV_WohPG@osx.local/T/#m2c05a982beeb14e7bf039c1d8db856734bf234c7 Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure") Signed-off-by: Frank Li Link: https://patch.msgid.link/20251016143814.2551256-1-Frank.Li@nxp.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin

i3c: Remove superfluous FIXME

2025-09-23T22:46:15+00:00

I2C adapters can already change timeout and retry parameters via IOCTL. This allows for better tuning to workloads compared to per-adapter defaults. So, the FIXME is not needed. Signed-off-by: Wolfram Sang Reviewed-by: Frank Li Link: https://lore.kernel.org/r/20250923203557.18298-2-wsa+renesas@sang-engineering.com Signed-off-by: Alexandre Belloni

i3c: Fix default I2C adapter timeout value

2025-09-16T15:06:43+00:00

Commit 3a379bbcea0a ("i3c: Add core I3C infrastructure") set the default adapter timeout for I2C transfers as 1000 (ms). However that parameter is defined in jiffies not in milliseconds. With mipi-i3c-hci driver this wasn't visible until commit c0a90eb55a69 ("i3c: mipi-i3c-hci: use adapter timeout value for I2C transfers"). Fix this by setting the default timeout as HZ (CONFIG_HZ) not 1000. Fixes: 1b84691e7870 ("i3c: dw: use adapter timeout value for I2C transfers") Fixes: be27ed672878 ("i3c: master: cdns: use adapter timeout value for I2C transfers") Fixes: c0a90eb55a69 ("i3c: mipi-i3c-hci: use adapter timeout value for I2C transfers") Fixes: a747e01adad2 ("i3c: master: svc: use adapter timeout value for I2C transfers") Fixes: d028219a9f14 ("i3c: master: Add basic driver for the Renesas I3C controller") Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure") Cc: stable@vger.kernel.org # 6.17 Signed-off-by: Jarkko Nikula Reviewed-by: Frank Li Reviewed-by: Wolfram Sang Link: https://lore.kernel.org/r/20250905100320.954536-1-jarkko.nikula@linux.intel.com Signed-off-by: Alexandre Belloni

i3c: master: Add helpers for DMA mapping and bounce buffer handling

2025-09-16T15:06:42+00:00

Some I3C controllers such as MIPI I3C HCI may pad the last DWORD (32-bit) with stale data from the RX FIFO in DMA transfers if the receive length is not DWORD aligned and when the device DMA is IOMMU mapped. In such a case, a properly sized bounce buffer is required in order to avoid possible data corruption. In a review discussion, proposal was to have a common helpers in I3C core for DMA mapping and bounce buffer handling. Drivers may use the helper i3c_master_dma_map_single() to map a buffer for a DMA transfer. It internally allocates a bounce buffer if buffer is not DMA'able or when the driver requires it for a transfer. Helper i3c_master_dma_unmap_single() does the needed cleanups and data copying from the bounce buffer. Signed-off-by: Jarkko Nikula Reviewed-by: Frank Li Link: https://lore.kernel.org/r/20250822105630.2820009-2-jarkko.nikula@linux.intel.com Signed-off-by: Alexandre Belloni

i3c: Standardize defines for specification parameters

2025-07-30T23:33:20+00:00

Align existing defines to follow the consistent pattern: I3C_BUS___. Prepare the codebase for adding new parameters and help avoid duplication. Signed-off-by: Wolfram Sang Tested-by: Tommaso Merciai Reviewed-by: Frank Li Link: https://lore.kernel.org/r/20250724094146.6443-2-wsa+renesas@sang-engineering.com Signed-off-by: Alexandre Belloni

i3c: prefix hexadecimal entries in sysfs

2025-07-07T21:18:58+00:00

Hexadecimal values in sysfs should be prefixed with '0x' like e.g. PCI and SCSI already do it. Also ensure the two digit length since BCR and DCR are a byte in size. Signed-off-by: Wolfram Sang Reviewed-by: Frank Li Link: https://lore.kernel.org/r/20250707115409.73545-2-wsa+renesas@sang-engineering.com Signed-off-by: Alexandre Belloni

i3c: master: replace ENOTSUPP with SUSV4-compliant EOPNOTSUPP

2025-07-07T21:14:46+00:00

Replace non-standard ENOTSUPP with the SUSV4-defined error code EOPNOTSUPP to fix below checkpatch warning: "ENOTSUPP is not a SUSV4 error code, prefer EOPNOTSUPP" Signed-off-by: Wolfram Sang Reviewed-by: Frank Li Link: https://lore.kernel.org/r/20250628192027.3932-6-wsa+renesas@sang-engineering.com Signed-off-by: Alexandre Belloni

i3c: don't fail if GETHDRCAP is unsupported

2025-07-07T21:14:26+00:00

'I3C_BCR_HDR_CAP' is still spec v1.0 and has been renamed to 'advanced capabilities' in v1.1 onwards. The ST pressure sensor LPS22DF does not have HDR, but has the 'advanced cap' bit set. The core still wants to get additional information using the CCC 'GETHDRCAP' (or GETCAPS in v1.1 onwards). Not all controllers support this CCC and will notify the upper layers about it. For instantiating the device, we can ignore this unsupported CCC as standard communication will work. Without this patch, the device will not be instantiated at all. Signed-off-by: Wolfram Sang Reviewed-by: Frank Li Link: https://lore.kernel.org/r/20250704204524.6124-1-wsa+renesas@sang-engineering.com Signed-off-by: Alexandre Belloni