kernel/git/stable/linux.git/drivers/i3c/device.c, branch master

i3c: master: Reject IBI requests from non-IBI-capable devices

2026-08-08T13:04:20+00:00

i3c_device_request_ibi() does not verify that a device advertises IBI support before attempting to set up IBI handling. Add a check for I3C_BCR_IBI_REQ_CAP and fail with -EOPNOTSUPP when IBI support is not reported by the device. This keeps IBI setup consistent with other IBI-related functionality, such as exposing wakeup capability only for IBI-capable devices. Signed-off-by: Adrian Hunter Reviewed-by: Frank Li Link: https://patch.msgid.link/20260807145638.168865-12-adrian.hunter@intel.com Signed-off-by: Alexandre Belloni

i3c: Make dev->desc locking assumptions explicit

2026-08-08T13:02:50+00:00

i3c_device_get_info() takes the bus normal-use lock before accessing dev->desc. Under that lock, the descriptor pointer is guaranteed to be valid for the duration of the access. Remove the unnecessary NULL check on dev->desc so the code more clearly reflects the locking rules and expected descriptor lifetime. Signed-off-by: Adrian Hunter Acked-by: Mukesh Savaliya Reviewed-by: Frank Li Link: https://patch.msgid.link/20260807145638.168865-6-adrian.hunter@intel.com Signed-off-by: Alexandre Belloni

i3c: Fix unlocked dereference of dev->desc in i3c_device_get_supported_xfer_mode()

2026-08-08T13:02:50+00:00

i3c_device_get_supported_xfer_mode() uses dev->desc to obtain the master controller. However, dev->desc must not be dereferenced unless bus->lock is held, and this function does not take that lock. The function only needs access to the master controller associated with the device's bus. Use dev->bus instead, which is always valid for the lifetime of the device and does not require dereferencing dev->desc. Fixes: 256a21743d91 ("i3c: Add HDR API support") Cc: stable@vger.kernel.org Signed-off-by: Adrian Hunter Reviewed-by: Frank Li Link: https://patch.msgid.link/20260807145638.168865-3-adrian.hunter@intel.com Signed-off-by: Alexandre Belloni

i3c: master: Introduce optional Runtime PM support

2026-01-14T16:21:10+00:00

Master drivers currently manage Runtime PM individually, but all require runtime resume for bus operations. This can be centralized in common code. Add optional Runtime PM support to ensure the parent device is runtime resumed before bus operations and auto-suspended afterward. Notably, do not call ->bus_cleanup() if runtime resume fails. Master drivers that opt-in to core runtime PM support must take that into account. Also provide an option to allow IBIs and hot-joins while runtime suspended. Signed-off-by: Adrian Hunter Reviewed-by: Frank Li Link: https://patch.msgid.link/20260113072702.16268-20-adrian.hunter@intel.com Signed-off-by: Alexandre Belloni

i3c: Add HDR API support

2025-11-28T23:39:07+00:00

Rename struct i3c_priv_xfer to struct i3c_xfer, since private xfer in the I3C spec refers only to SDR transfers. Ref: i3c spec ver1.2, section 3, Technical Overview. i3c_xfer will be used for both SDR and HDR. Rename enum i3c_hdr_mode to i3c_xfer_mode. Previous definition need match CCC GET_CAP1 bit position. Use 31 as SDR transfer mode. Add i3c_device_do_xfers() with an xfer mode argument, while keeping i3c_device_do_priv_xfers() as a wrapper that calls i3c_device_do_xfers() with I3C_SDR for backward compatibility. Introduce a 'cmd' field in struct i3c_xfer as an anonymous union with 'rnw', since HDR mode uses read/write commands instead of the SDR address bit. Add .i3c_xfers() callback for master controllers. If not implemented, fall back to SDR with .priv_xfers(). The .priv_xfers() API can be removed once all controllers switch to .i3c_xfers(). Add 'mode_mask' bitmask to advertise controller capability. Signed-off-by: Frank Li Link: https://patch.msgid.link/20251106-i3c_ddr-v11-1-33a6a66ed095@nxp.com Signed-off-by: Alexandre Belloni

i3c: Fix i3c_device_do_priv_xfers() kernel-doc indentation

2025-07-30T23:23:12+00:00

Sphinx reports indentation warning on i3c_device_do_priv_xfers() return value list: Documentation/driver-api/i3c/device-driver-api:9: ./drivers/i3c/device.c:31: ERROR: Unexpected indentation. [docutils] Format the list as bullet list to fix the warning. Signed-off-by: Bagas Sanjaya Reviewed-by: Randy Dunlap Tested-by: Randy Dunlap Reviewed-by: Frank Li Link: https://lore.kernel.org/r/20250702040424.18577-1-bagasdotme@gmail.com Signed-off-by: Alexandre Belloni

i3c: Add comment for -EAGAIN in i3c_device_do_priv_xfers()

2024-05-22T22:29:19+00:00

In accordance with I3C spec ver 1.1.1 09-Jun-2021, section: 5.1.2.2.3, if a target requests hot join (HJ), In-Band Interrupt (IBI), or controller role request (CRR) during the emission of an I3C address in i3c_device_do_priv_xfers(), the target may win bus arbitration. In such cases, it is imperative to notify the I3C client driver and retry i3c_device_do_priv_xfers() after some delay. Signed-off-by: Frank Li Reviewed-by: Miquel Raynal Link: https://lore.kernel.org/r/20240506164009.21375-1-Frank.Li@nxp.com Signed-off-by: Alexandre Belloni

driver core: make struct device_type.uevent() take a const *

2023-01-27T12:45:36+00:00

The uevent() callback in struct device_type should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Cc: Alan Stern Cc: Andreas Noever Cc: Andy Shevchenko Cc: Bard Liao Cc: Chaitanya Kulkarni Cc: Dan Williams Cc: Dmitry Torokhov Cc: Frank Rowand Cc: Ira Weiny Cc: Jason Gunthorpe Cc: Jens Axboe Cc: Jilin Yuan Cc: Jiri Slaby Cc: Len Brown Cc: Mark Gross Cc: "Martin K. Petersen" Cc: "Matthew Wilcox (Oracle)" Cc: Maximilian Luz Cc: Michael Jamet Cc: Ming Lei Cc: Pierre-Louis Bossart Cc: Rob Herring Cc: Sakari Ailus Cc: Sanyog Kale Cc: Sean Young Cc: Stefan Richter Cc: Thomas Gleixner Cc: Won Chung Cc: Yehezkel Bernat Acked-by: Rafael J. Wysocki Acked-by: Mika Westerberg # for Thunderbolt Acked-by: Mauro Carvalho Chehab Acked-by: Alexandre Belloni Acked-by: Heikki Krogerus Acked-by: Wolfram Sang Acked-by: Vinod Koul Acked-by: Hans de Goede Link: https://lore.kernel.org/r/20230111113018.459199-6-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

i3c: move dev_to_i3cdev() to use container_of_const()

2023-01-27T12:45:32+00:00

The driver core is changing to pass some pointers as const, so move dev_to_i3cdev() to use container_of_const() to handle this change. dev_to_i3cdev() now properly keeps the const-ness of the pointer passed into it, while as before it could be lost. Acked-by: Alexandre Belloni Acked-by: Hans de Goede Link: https://lore.kernel.org/r/20230111113018.459199-3-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

i3c: export SETDASA method

2022-12-11T20:25:58+00:00

Because not all I3C drivers have the hot-join feature ready, and especially not all I3C devices support hot-join feature, exporting SETDASA method could be useful. With this function, the I3C controller could perform a DAA to I3C devices when users decide to turn these I3C devices off and on again during run-time. Tested: This change has been tested with turnning off an I3C device and turning on it again during run-time. The device driver calls SETDASA method to perform DAA to the device. And communication between I3C controller and device is set up again correctly. Signed-off-by: Jack Chen Link: https://lore.kernel.org/r/20221207205059.3848851-1-zenghuchen@google.com Signed-off-by: Alexandre Belloni