i3c: Add NULL pointer check in i3c_master_queue_ibi()

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_ib

i3c: Add NULL pointer check in i3c_master_queue_ibi()

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: [email protected]
Link: https://lore.kernel.org/lkml/Z9gjGYudiYyl3bSe@lizhi-Precision-Tower-5810/
Signed-off-by: Manjunatha Venkatesh <[email protected]>
Reviewed-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: Drop duplicate check before calling OF APIs

OF APIs are usually NULL-aware and returns an error in case when
device node is not present or supported. We already have a check
for the ret

i3c: master: Drop duplicate check before calling OF APIs

OF APIs are usually NULL-aware and returns an error in case when
device node is not present or supported. We already have a check
for the returned value, no need to check for the parameter.

Signed-off-by: Andy Shevchenko <[email protected]>
Reviewed-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: Improve initialization of numbered I2C adapters

Add logic to initialize I2C adapters with a specific ID if available,
improving device identification and configuration.

For mixed buses

i3c: master: Improve initialization of numbered I2C adapters

Add logic to initialize I2C adapters with a specific ID if available,
improving device identification and configuration.

For mixed buses, in addition to the i3c alias, an i2c alias can be added to
assign a fixed bus number to the i2c adapter.

This allows an alias node such as:
aliases {
i2c2 = &mixed_bus_a,
i3c2 = &mixed_bus_a,
i3c4 = &mixed_bus_b,
};

/* assigned "i3c-2" and "i2c-2" */
mixed_bus_a: i3c-master {
};

If there is no i2c alias for a mixed bus, the i2c adapter numbers will
remain as is and will be assigned starting after the highest fixed bus
number.

/* assigned "i3c-4" and likely assigned "i2c-3" */
mixed_bus_b: i3c-master {
};

Signed-off-by: Defa Li <[email protected]>
Reviewed-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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

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_i

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

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: [email protected]
Fixes: aef79e189ba2 ("i3c: master: support to adjust first broadcast address speed")
Signed-off-by: Frank Li <[email protected]>
Reviewed-by: Wolfram Sang <[email protected]>
Tested-by: Wolfram Sang <[email protected]>
Acked-by: Mukesh Kumar Savaliya <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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

A deadlock may happen since the i3c_master_register() acquires
&i3cbus->lock twice. See the log below.
Use i3cd

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

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 <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: Fix miss free init_dyn_addr at i3c_master_put_i3c_addrs()

if (dev->boardinfo && dev->boardinfo->init_dyn_addr)
^^^ here check "init_dyn_addr"
i3c_

i3c: master: Fix miss free init_dyn_addr at i3c_master_put_i3c_addrs()

if (dev->boardinfo && dev->boardinfo->init_dyn_addr)
^^^ here check "init_dyn_addr"
i3c_bus_set_addr_slot_status(&master->bus, dev->info.dyn_addr, ...)
^^^^
free "dyn_addr"
Fix copy/paste error "dyn_addr" by replacing it with "init_dyn_addr".

Cc: [email protected]
Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure")
Reviewed-by: Miquel Raynal <[email protected]>
Signed-off-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: Remove i3c_dev_disable_ibi_locked(olddev) on device hotjoin

When a new device hotjoins, a new dynamic address is assigned.
i3c_master_add_i3c_dev_locked() identifies that the device was

i3c: master: Remove i3c_dev_disable_ibi_locked(olddev) on device hotjoin

When a new device hotjoins, a new dynamic address is assigned.
i3c_master_add_i3c_dev_locked() identifies that the device was previously
attached to the bus and locates the olddev.

i3c_master_add_i3c_dev_locked()
{
...
olddev = i3c_master_search_i3c_dev_duplicate(newdev);
...
if (olddev) {
...
i3c_dev_disable_ibi_locked(olddev);
^^^^^^
The olddev should not receive any commands on the i3c bus as it
does not exist and has been assigned a new address. This will
result in NACK or timeout. So remove it.
}

i3c_dev_free_ibi_locked(olddev);
^^^^^^^^
This function internally calls i3c_dev_disable_ibi_locked() function
causing to send DISEC command with old Address.

The olddev should not receive any commands on the i3c bus as it
does not exist and has been assigned a new address. This will
result in NACK or timeout. So, update the olddev->ibi->enabled
flag to false to avoid DISEC with OldAddr.
}

Include part of Ravindra Yashvant Shinde's work:
https://lore.kernel.org/linux-i3c/[email protected]/T/#u

Fixes: 317bacf960a4 ("i3c: master: add enable(disable) hot join in sys entry")
Co-developed-by: Ravindra Yashvant Shinde <[email protected]>
Signed-off-by: Ravindra Yashvant Shinde <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Signed-off-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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

If the DTS contains 'assigned-address', a dynamic address leak occurs
during hotjoin events.

Assume a device have assigned-a

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

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: [email protected]
Reviewed-by: Miquel Raynal <[email protected]>
Signed-off-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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

Extend the address status bit to 4 and introduce the
I3C_ADDR_SLOT_EXT_DESIRED macro to indicate that a device prefers a

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

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 <[email protected]>
Signed-off-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: Replace hard code 2 with macro I3C_ADDR_SLOT_STATUS_BITS

Replace the hardcoded value 2, which indicates 2 bits for I3C address
status, with the predefined macro I3C_ADDR_SLOT_STATUS_BIT

i3c: master: Replace hard code 2 with macro I3C_ADDR_SLOT_STATUS_BITS

Replace the hardcoded value 2, which indicates 2 bits for I3C address
status, with the predefined macro I3C_ADDR_SLOT_STATUS_BITS.

Improve maintainability and extensibility of the code.

Reviewed-by: Miquel Raynal <[email protected]>
Signed-off-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: support to adjust first broadcast address speed

According to I3C spec 6.2 Timing Specification, the Open Drain High Period
of SCL Clock timing for first broadcast address should be adju

i3c: master: support to adjust first broadcast address speed

According to I3C spec 6.2 Timing Specification, the Open Drain High Period
of SCL Clock timing for first broadcast address should be adjusted to 200ns
at least. I3C device working as i2c device will see the broadcast to close
its Spike Filter then change to work at I3C mode. After that I3C open drain
SCL high level should be adjusted back.

Signed-off-by: Carlos Song <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Reviewed-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: Enhance i3c_bus_type visibility for device searching & event monitoring

Improve the visibility of i3c_bus_type to facilitate searching for
i3c devices attached to the i3c bus. Enable ot

i3c: master: Enhance i3c_bus_type visibility for device searching & event monitoring

Improve the visibility of i3c_bus_type to facilitate searching for
i3c devices attached to the i3c bus. Enable other drivers to use
bus_register_notifier to monitor i3c bus device events.

Signed-off-by: Bhoomik Gupta <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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driver core: have match() callback in struct bus_type take a const *

In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *. This

driver core: have match() callback in struct bus_type take a const *

In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *. This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.

Because the match() callback is in all busses, all busses are modified
to handle this properly. This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.

For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.

Cc: Rafael J. Wysocki <[email protected]>
Reviewed-by: Alex Elder <[email protected]>
Acked-by: Sumit Garg <[email protected]>
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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i3c: master: Enable runtime PM for master controller

Enable runtime PM for i3c master node during master registration time.

Sometimes i3c client device driver may want to control the PM of the
pare

i3c: master: Enable runtime PM for master controller

Enable runtime PM for i3c master node during master registration time.

Sometimes i3c client device driver may want to control the PM of the
parent (master) to perform the transactions and save the power in an
efficient way by controlling the session. Hence device can call PM
APIs by passing the parent node.

Here, I3C target device when calls pm_runtime_get_sync(dev->parent)
couldn't invoke master drivers runtime PM callback registered by
the master driver because parent's PM status was disabled in the
Master node.

Also call pm_runtime_no_callbacks() and pm_suspend_ignore_children()
for the master node to not have any callback addition and ignore the
children to have runtime PM work just locally in the driver. This
should be generic and common change for all i3c devices and should
not have any other impact.

With these changes, I3C client device works and able to invoke
master driver registered runtime PM callbacks.

Signed-off-by: Mukesh Kumar Savaliya <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: Make i3c_bus_type const

Since commit d492cc2573a0 ("driver core: device.h: make struct
bus_type a const *"), the driver core can properly handle constant
struct bus_type, move the i3c_bus_type

i3c: Make i3c_bus_type const

Since commit d492cc2573a0 ("driver core: device.h: make struct
bus_type a const *"), the driver core can properly handle constant
struct bus_type, move the i3c_bus_type variable to be a constant
structure as well, placing it into read-only memory which can not be
modified at runtime.

Cc: Greg Kroah-Hartman <[email protected]>
Suggested-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Ricardo B. Marliere <[email protected]>
Reviewed-by: Greg Kroah-Hartman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: add enable(disable) hot join in sys entry

Add hotjoin entry in sys file system allow user enable/disable hotjoin
feature.

Add (*enable(disable)_hotjoin)() to i3c_master_controller_ops.

i3c: master: add enable(disable) hot join in sys entry

Add hotjoin entry in sys file system allow user enable/disable hotjoin
feature.

Add (*enable(disable)_hotjoin)() to i3c_master_controller_ops.
Add api i3c_master_enable(disable)_hotjoin();

Signed-off-by: Frank Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: Fix build error

Fix build error caused by commit 2aac0bf4ebc8 ("i3c: Add fallback method
for GETMXDS CCC") which incorrectly access the "struct i3c_ccc_cmd_dest
dest" as pointer.

drive

i3c: master: Fix build error

Fix build error caused by commit 2aac0bf4ebc8 ("i3c: Add fallback method
for GETMXDS CCC") which incorrectly access the "struct i3c_ccc_cmd_dest
dest" as pointer.

drivers/i3c/master.c: In function ‘i3c_master_getmxds_locked’:
drivers/i3c/master.c:1140:21: error: invalid type argument of ‘->’ (have ‘struct i3c_ccc_cmd_dest’)
1140 | dest->payload.len -= 3;
| ^~

Fixes: 2aac0bf4ebc8 ("i3c: Add fallback method for GETMXDS CCC")
Signed-off-by: Jarkko Nikula <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: Add fallback method for GETMXDS CCC

Some I3C hardware will report error when an incorrect length is received from
device. GETMXDS CCC are available in 2 formats: without turnaround time (format

i3c: Add fallback method for GETMXDS CCC

Some I3C hardware will report error when an incorrect length is received from
device. GETMXDS CCC are available in 2 formats: without turnaround time (format
1) and with turnaround time (format 2). There is no mechanics to determine which
format is supported by device. So in case sending GETMXDS CCC format 2 resulted
in a failure, try sending GETMXDS CCC format 1 instead.

Signed-off-by: Joshua Yeong <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: handle IBIs in order they came

IBI shall be handled in order they appear on the bus. Otherwise could hit
case when order of handling them in device driver will be different. It may
lead

i3c: master: handle IBIs in order they came

IBI shall be handled in order they appear on the bus. Otherwise could hit
case when order of handling them in device driver will be different. It may
lead to invalid assembling fragmented packets or events order broken.

Added separate workqueue with option WQ_MEM_RECLAIM for each device driver.
This ensures IBI handling order and improves IBI handling performance: IBI
handlers for device B are not blocked by IBI handlers for device A.

Original solution (single workqueue in main driver) was able to handle also
general IBI (not related to specific device) like HJ or MR. So leaving this
for such purposes.

Signed-off-by: Zbigniew Lukwinski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: Add support for bus enumeration & notification

This allows other drivers to be notified when new i3c busses are
attached, referring to a whole i3c bus as opposed to individual
devices.

Signed-

i3c: Add support for bus enumeration & notification

This allows other drivers to be notified when new i3c busses are
attached, referring to a whole i3c bus as opposed to individual
devices.

Signed-off-by: Jeremy Kerr <[email protected]>
Signed-off-by: Matt Johnston <[email protected]>
Acked-by: Alexandre Belloni <[email protected]>
Signed-off-by: Paolo Abeni <[email protected]>

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i3c: Fix potential refcount leak in i3c_master_register_new_i3c_devs

put_device() needs to be called on failure of device_register()
to give up the reference initialized in it to avoid refcount leak

i3c: Fix potential refcount leak in i3c_master_register_new_i3c_devs

put_device() needs to be called on failure of device_register()
to give up the reference initialized in it to avoid refcount leak.

Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure")
Signed-off-by: Dinghao Liu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: Inherit DMA masks and parameters from parent device

Copy the DMA masks and parameters for an I3C master device from parent
device so that the master device has them set for the DMA buff

i3c: master: Inherit DMA masks and parameters from parent device

Copy the DMA masks and parameters for an I3C master device from parent
device so that the master device has them set for the DMA buffer and
mapping API.

Signed-off-by: Jarkko Nikula <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: replace deprecated strncpy

`strncpy` is deprecated for use on NUL-terminated destination strings [1].

We should prefer more robust and less ambiguous string interfaces.

We expect adap->name t

i3c: replace deprecated strncpy

`strncpy` is deprecated for use on NUL-terminated destination strings [1].

We should prefer more robust and less ambiguous string interfaces.

We expect adap->name to be NUL-terminated based on i2c_adapter name use:
| dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name);

NUL-padding does not seem to be required as `master` is zero-allocated
and `i3c_master_to_i2c_adapter` simply returns a field from within
`master`:
| master = devm_kzalloc(dev, sizeof(*master), GFP_KERNEL);
...
| struct i2c_adapter *adap = i3c_master_to_i2c_adapter(master);
...
| static struct i2c_adapter *
| i3c_master_to_i2c_adapter(struct i3c_master_controller *master)
| {
| return &master->i2c;
| }

This means that `adap->name` should already be filled with NUL-bytes.

Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: [email protected]
Signed-off-by: Justin Stitt <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Link: https://lore.kernel.org/r/20230921-strncpy-drivers-i3c-master-c-v1-1-9fdb8d8169e1@google.com
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: master: Fix SETDASA process

When a I3C DT node has a static_addr and an init_dyn_addr,the
init_dyn_addr is reserved in i3c_master_bus_init() and then
the static_addr is reserved in i3c_master_e

i3c: master: Fix SETDASA process

When a I3C DT node has a static_addr and an init_dyn_addr,the
init_dyn_addr is reserved in i3c_master_bus_init() and then
the static_addr is reserved in i3c_master_early_i3c_dev_add().
But if the dynamic address is same as static then above
procedure would fail.
Add a check to pass i3c_bus_get_addr_slot_status() when static
and dynamic address are equal.

Signed-off-by: Aniket <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: Allow OF-alias-based persistent bus numbering

Parse the /aliases node to assign any fixed bus numbers, as is done with
the i2c subsystem. Numbering for non-aliased busses will start after the
h

i3c: Allow OF-alias-based persistent bus numbering

Parse the /aliases node to assign any fixed bus numbers, as is done with
the i2c subsystem. Numbering for non-aliased busses will start after the
highest fixed bus number.

This allows an alias node such as:

aliases {
i3c0 = &bus_a,
i3c4 = &bus_b,
};

to set the numbering for a set of i3c controllers:

/* fixed-numbered bus, assigned "i3c-0" */
bus_a: i3c-master {
};

/* another fixed-numbered bus, assigned "i3c-4" */
bus_b: i3c-master {
};

/* dynamic-numbered bus, likely assigned "i3c-5" */
bus_c: i3c-master {
};

If no i3c device aliases are present, the numbering will stay as-is,
starting from 0.

Signed-off-by: Jeremy Kerr <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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