kernel/linux.git/drivers/i3c/master.c, branch v6.12.80

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

2026-03-04T12:19:22+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

2026-03-04T12:19:22+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

2025-12-18T12:54:50+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: master: Initialize ret in i3c_i2c_notifier_call()

2025-08-20T16:30:46+00:00

[ Upstream commit 290ce8b2d0745e45a3155268184523a8c75996f1 ] Set ret to -EINVAL if i3c_i2c_notifier_call() receives an invalid action, resolving uninitialized warning. Signed-off-by: Jorge Marques Reviewed-by: Frank Li Link: https://lore.kernel.org/r/20250622-i3c-master-ret-uninitialized-v1-1-aabb5625c932@analog.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin

i3c: don't fail if GETHDRCAP is unsupported

2025-08-20T16:30:46+00:00

[ Upstream commit 447270cdb41b1c8c3621bb14b93a6749f942556e ] '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 Signed-off-by: Sasha Levin

i3c: Add NULL pointer check in i3c_master_queue_ibi()

2025-04-20T08:15:44+00:00

commit bd496a44f041da9ef3afe14d1d6193d460424e91 upstream. The I3C master driver may receive an IBI from a target device that has not been probed yet. In such cases, the master calls `i3c_master_queue_ibi()` to queue an IBI work task, leading to "Unable to handle kernel read from unreadable memory" and resulting in a kernel panic. Typical IBI handling flow: 1. The I3C master scans target devices and probes their respective drivers. 2. The target device driver calls `i3c_device_request_ibi()` to enable IBI and assigns `dev->ibi = ibi`. 3. The I3C master receives an IBI from the target device and calls `i3c_master_queue_ibi()` to queue the target device driver’s IBI handler task. However, since target device events are asynchronous to the I3C probe sequence, step 3 may occur before step 2, causing `dev->ibi` to be `NULL`, leading to a kernel panic. Add a NULL pointer check in `i3c_master_queue_ibi()` to prevent accessing an uninitialized `dev->ibi`, ensuring stability. Fixes: 3a379bbcea0af ("i3c: Add core I3C infrastructure") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/lkml/Z9gjGYudiYyl3bSe@lizhi-Precision-Tower-5810/ Signed-off-by: Manjunatha Venkatesh Reviewed-by: Frank Li Link: https://lore.kernel.org/r/20250326123047.2797946-1-manjunatha.venkatesh@nxp.com Signed-off-by: Alexandre Belloni Signed-off-by: Greg Kroah-Hartman

i3c: master: Fix missing 'ret' assignment in set_speed()

2025-02-17T09:05:40+00:00

commit b266e0d4dac00eecdfaf50ec3f708fd0c3b39637 upstream. Fix a probe failure in the i3c master driver that occurs when no i3c devices are connected to the bus. The issue arises in `i3c_master_bus_init()` where the `ret` value is not updated after calling `master->ops->set_speed()`. If no devices are present, `ret` remains set to `I3C_ERROR_M2`, causing the code to incorrectly proceed to `err_bus_cleanup`. Cc: stable@vger.kernel.org Fixes: aef79e189ba2 ("i3c: master: support to adjust first broadcast address speed") Signed-off-by: Frank Li Reviewed-by: Wolfram Sang Tested-by: Wolfram Sang Acked-by: Mukesh Kumar Savaliya Reviewed-by: Miquel Raynal Link: https://lore.kernel.org/r/20250108225533.915334-1-Frank.Li@nxp.com Signed-off-by: Alexandre Belloni Signed-off-by: Greg Kroah-Hartman

i3c: Use i3cdev->desc->info instead of calling i3c_device_get_info() to avoid deadlock

2024-12-14T19:04:05+00:00

[ Upstream commit 6cf7b65f7029914dc0cd7db86fac9ee5159008c6 ] A deadlock may happen since the i3c_master_register() acquires &i3cbus->lock twice. See the log below. Use i3cdev->desc->info instead of calling i3c_device_info() to avoid acquiring the lock twice. v2: - Modified the title and commit message ============================================ WARNING: possible recursive locking detected 6.11.0-mainline -------------------------------------------- init/1 is trying to acquire lock: f1ffff80a6a40dc0 (&i3cbus->lock){++++}-{3:3}, at: i3c_bus_normaluse_lock but task is already holding lock: f1ffff80a6a40dc0 (&i3cbus->lock){++++}-{3:3}, at: i3c_master_register other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&i3cbus->lock); lock(&i3cbus->lock); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by init/1: #0: fcffff809b6798f8 (&dev->mutex){....}-{3:3}, at: __driver_attach #1: f1ffff80a6a40dc0 (&i3cbus->lock){++++}-{3:3}, at: i3c_master_register stack backtrace: CPU: 6 UID: 0 PID: 1 Comm: init Call trace: dump_backtrace+0xfc/0x17c show_stack+0x18/0x28 dump_stack_lvl+0x40/0xc0 dump_stack+0x18/0x24 print_deadlock_bug+0x388/0x390 __lock_acquire+0x18bc/0x32ec lock_acquire+0x134/0x2b0 down_read+0x50/0x19c i3c_bus_normaluse_lock+0x14/0x24 i3c_device_get_info+0x24/0x58 i3c_device_uevent+0x34/0xa4 dev_uevent+0x310/0x384 kobject_uevent_env+0x244/0x414 kobject_uevent+0x14/0x20 device_add+0x278/0x460 device_register+0x20/0x34 i3c_master_register_new_i3c_devs+0x78/0x154 i3c_master_register+0x6a0/0x6d4 mtk_i3c_master_probe+0x3b8/0x4d8 platform_probe+0xa0/0xe0 really_probe+0x114/0x454 __driver_probe_device+0xa0/0x15c driver_probe_device+0x3c/0x1ac __driver_attach+0xc4/0x1f0 bus_for_each_dev+0x104/0x160 driver_attach+0x24/0x34 bus_add_driver+0x14c/0x294 driver_register+0x68/0x104 __platform_driver_register+0x20/0x30 init_module+0x20/0xfe4 do_one_initcall+0x184/0x464 do_init_module+0x58/0x1ec load_module+0xefc/0x10c8 __arm64_sys_finit_module+0x238/0x33c invoke_syscall+0x58/0x10c el0_svc_common+0xa8/0xdc do_el0_svc+0x1c/0x28 el0_svc+0x50/0xac el0t_64_sync_handler+0x70/0xbc el0t_64_sync+0x1a8/0x1ac Signed-off-by: Defa Li Link: https://lore.kernel.org/r/20241107132549.25439-1-defa.li@mediatek.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin

i3c: master: Fix dynamic address leak when 'assigned-address' is present

2024-12-14T19:03:13+00:00

[ Upstream commit 851bd21cdb55e727ab29280bc9f6b678164f802a ] If the DTS contains 'assigned-address', a dynamic address leak occurs during hotjoin events. Assume a device have assigned-address 0xb. - Device issue Hotjoin - Call i3c_master_do_daa() - Call driver xxx_do_daa() - Call i3c_master_get_free_addr() to get dynamic address 0x9 - i3c_master_add_i3c_dev_locked(0x9) - expected_dyn_addr = newdev->boardinfo->init_dyn_addr (0xb); - i3c_master_reattach_i3c_dev(newdev(0xb), old_dyn_addr(0x9)); - if (dev->info.dyn_addr != old_dyn_addr && ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 0xb != 0x9 -> TRUE (!dev->boardinfo || ^^^^^^^^^^^^^^^ -> FALSE dev->info.dyn_addr != dev->boardinfo->init_dyn_addr)) { ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 0xb != 0xb -> FALSE ... i3c_bus_set_addr_slot_status(&master->bus, old_dyn_addr, I3C_ADDR_SLOT_FREE); ^^^ This will be skipped. So old_dyn_addr never free } - i3c_master_get_free_addr() will return increased sequence number. Remove dev->info.dyn_addr != dev->boardinfo->init_dyn_addr condition check. dev->info.dyn_addr should be checked before calling this function because i3c_master_setnewda_locked() has already been called and the target device has already accepted dyn_addr. It is too late to check if dyn_addr is free in i3c_master_reattach_i3c_dev(). Add check to ensure expected_dyn_addr is free before i3c_master_setnewda_locked(). Fixes: cc3a392d69b6 ("i3c: master: fix for SETDASA and DAA process") Cc: stable@kernel.org Reviewed-by: Miquel Raynal Signed-off-by: Frank Li Link: https://lore.kernel.org/r/20241021-i3c_dts_assign-v8-3-4098b8bde01e@nxp.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin

i3c: master: Extend address status bit to 4 and add I3C_ADDR_SLOT_EXT_DESIRED

2024-12-14T19:03:12+00:00

[ Upstream commit 2f552fa280590e61bd3dbe66a7b54b99caa642a4 ] Extend the address status bit to 4 and introduce the I3C_ADDR_SLOT_EXT_DESIRED macro to indicate that a device prefers a specific address. This is generally set by the 'assigned-address' in the device tree source (dts) file. ┌────┬─────────────┬───┬─────────┬───┐ │S/Sr│ 7'h7E RnW=0 │ACK│ ENTDAA │ T ├────┐ └────┴─────────────┴───┴─────────┴───┘ │ ┌─────────────────────────────────────────┘ │ ┌──┬─────────────┬───┬─────────────────┬────────────────┬───┬─────────┐ └─►│Sr│7'h7E RnW=1 │ACK│48bit UID BCR DCR│Assign 7bit Addr│PAR│ ACK/NACK│ └──┴─────────────┴───┴─────────────────┴────────────────┴───┴─────────┘ Some master controllers (such as HCI) need to prepare the entire above transaction before sending it out to the I3C bus. This means that a 7-bit dynamic address needs to be allocated before knowing the target device's UID information. However, some I3C targets may request specific addresses (called as "init_dyn_addr"), which is typically specified by the DT-'s assigned-address property. Lower addresses having higher IBI priority. If it is available, i3c_bus_get_free_addr() preferably return a free address that is not in the list of desired addresses (called as "init_dyn_addr"). This allows the device with the "init_dyn_addr" to switch to its "init_dyn_addr" when it hot-joins the I3C bus. Otherwise, if the "init_dyn_addr" is already in use by another I3C device, the target device will not be able to switch to its desired address. If the previous step fails, fallback returning one of the remaining unassigned address, regardless of its state in the desired list. Reviewed-by: Miquel Raynal Signed-off-by: Frank Li Link: https://lore.kernel.org/r/20241021-i3c_dts_assign-v8-2-4098b8bde01e@nxp.com Signed-off-by: Alexandre Belloni Stable-dep-of: 851bd21cdb55 ("i3c: master: Fix dynamic address leak when 'assigned-address' is present") Signed-off-by: Sasha Levin